20201330288Identification of Flow Physics in a Counter Rotating Turbine22Flow in a Counter Rotating Turbine (CRT) stage is composite and three dimensional due to the blade geometry of nozzle, rotor 1 and rotor 2 that are twisted along the span, spacing between them, tip clearance provided on rotors and also because of oppositely rotating rotors. Present work analyzes the flow field through the nozzle and rotors at planes taken at various axial chord distances. Blade-to-blade contours and the hub-to-tip plots reveal the actual scenario of flow in the turbine stage. Nozzle and the two rotors are modeled in case of the CRT configuration. Boundary conditions are specified as pressure at inlet of the nozzle and flow rate at the outlet of rotor 2. Total pressure, velocity, entropy and TKE distribution through the blades are used to identify the flow over CRT. Flow through the blade rows is distinguished by effects of boundary layer, secondary flows near the hub, pressure gradient effects, presence of vortical flow structures in the passage and near the tip. Total pressure distribution near the midspan in case of nozzle and rotors show the presence of boundary layers and wake regions. Entropy and TKE contours show the loss regions in all the blade rows. Flow losses are more in rotor 2 than rotor 1. Secondary velocity vectors show the presence of vortex regions in the passage and tip clearance. Blade-to-blade contours of CRT reveal the actual flow scenario surrounding the blades. Hub-to-tip plots show the variations of flow parameters while moving from the bottom to top most position of blade. Thus, the present work identifies the exact flow structure in a counter rotating turbine and paves the way for researchers to negotiate flow losses and improve the CRT performance further. 767777R.SubbaraoDepartment of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036, IndiaDepartment of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036, Indiapaysrsubbarao@hotmail.comM.GovardhanDepartment of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036, IndiaDepartment of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036, Indiapaysgova@iitm.ac.inCounter Rotating Turbine (CRT) Blade-to-Blade contours Hub-to-Tip plots Vortices Flow losses.[Dring, R. P., H. D. Joslyn, and M. F. Blair (1987). The effect of inlet turbulence and rotor/stator interactions on the aerodynamics and heat transfer of large scale rotating turbine model. NASA Report, CR 179469.##
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]The Characteristics of Self-Resonating Jet Issuing from the Helmholtz Nozzle Combined with a Venturi Tube Structure22Self-resonating waterjet is a new type of waterjet technology that has been widely used for many practical applications. In order to further improve the performance of self-resonating waterjet, the Helmholtz nozzle was improved by replacing the upper part of a traditional contract structure with a venture tube one. This composite nozzle of a venturi tube structure and a Helmholtz resonator was proposed based on the working mechanism of self-resonating waterjet nozzles and the instability of cavitation flow in venturi tubes. Furthermore, the results were also compared with those generated by a conventional Helmholtz nozzle under the same conditions. The frequency of the pressure pulsation in the oscillating cavity and at the outlet was obtained and analyzed by the classical Fast Fourier transform (FFT) method. The results showed that the main frequency of the pressure oscillation rises to 2362.78Hz, and the peak and average values of the pressure are increased by 45% and 12.5% respectively at the outlet of the composite nozzle. In the oscillating cavity of composite nozzle, the pressure oscillations in the central region have higher frequencies and amplitudes, while near the wall are reversed.779791M.YuanHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, ChinaHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, Chinapaysyuanmiao125@live.comD.LiHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, ChinaHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, Chinapays2008lee@whu.edu.cnY.KangHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, ChinaHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, Chinapayskangyong@whu.edu.cnH.ShiHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, ChinaHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, Chinapays1171888144@qq.comY.HuHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, ChinaHubei Key Laboratory of Waterjet Theory and New Technology, Wuhan University, Wuhan 430072, Chinapayshuxiaoyi@whu.edu.cnSelf-resonating waterjet Oscillation characteristics Numerical simulation Classical Fast Fourier Transform (FFT) method.[Annoni, M., L. Cristaldi, M. Norgia, and C. Svelto, (2008). Measurement of water jet velocity distribution using laser velocimetry. IEEE Transactions on Instrumentation and Measurement 57(8), 1524-1528.##
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]Aerodynamic Optimization of Unmanned Aerial Vehicle through Propeller Improvements22This paper aimed at presenting a number of suggested improvements that can enhance the performance of a multi-rotor Unmanned Aerial Vehicle. Evaluating each suggestion in terms of the added benefits and feasibility concluded a final choice, which is incorporating a sinusoidal leading-edge profile to the propeller. This choice was numerically investigated with ANSYS Fluent 16.1 through the SST K-Omega turbulence model. The performance of the modified propeller was assessed by comparing the lift and drag results to the same propeller with a straight leading-edge under the same conditions. Both models were studied at pre-stall and post-stall conditions to see the performance effect with respect to the angle of attack. The findings of this research showed 7% increase in the lift force and coefficient that were associated with the addition of the sinusoidal leading-edge including improved recovery from stall spanning from angle of attack that extends between 10° to 25°. This research also provides more insights into how the delayed stall and improved lift help the multirotor to extend flight time and carry heavier payloads. It allows for the exploration of the inner working of the sinusoidal leading-edge and its relationship with the flow field over the propeller.793803A. F.ElGhazaliMechanical Engineering Department, Abu Dhabi University, Abu Dhabi, Abu Dhabi, UAEMechanical Engineering Department, Abu Dhabi University, Abu Dhabi, Abu Dhabi, UAEpays1058652@students.adu.ac.aeS. S.DolMechanical Engineering Department, Abu Dhabi University, Abu Dhabi, Abu Dhabi, UAEMechanical Engineering Department, Abu Dhabi University, Abu Dhabi, Abu Dhabi, UAEpayssharulshambin.dol@adu.ac.aeUnmanned aerial vehicle Numerical investigation Stall Sinusoidal leading-edge. [AskNature. (2016, September 14). Flippers provide lift, reduce drag. Retrieved from https://asknature.org: https://asknature.org/ strategy/flippers-provide-lift-reduce-drag/#.XH_GdCgzbIU##
Colomina, I. and P. Molina (2014). Unmanned aerial systems for photogrammetry and remote sensing: A review. ISPRS Journal of Photogrammetry and Remote Sensing, 79–97.##
Corsini, A., G. Delibra and A. G. Sheard (2013). On the Role of Leading-Edge Bumps in the Control of Stall Onset in Axial Fan Blades. Journal of Fluids Engineering-transactions of The Asme, 135(8), 081104. ##
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Johari, H., C. W. Henoch, D. Custodio, and A. Levshin, (2007). Effects of Leading-Edge Protuberances on Airfoil Performance. AIAA Journal 45(11) 2634-2642.##
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]Substitute model and CFD Investigations of a Coalescer in a Three-Phase Crude Oil Gravity Separator22The flow structure in a three-phase gas-oil-water separator and its performance was the main objective of the presented investigations, for which the Euler-Euler multiphase model to simulate the flow was used. The main assumption of the model is that secondary phases, consisting of oil and water droplets, are mono-dispersed with no coalescence and breakup. The considered separator is a part of the installation operated by a drilling company. In general, the investigation of separation process is very computationally expensive and time-consuming, therefore it is desirable to search for some simplifications in order to be able to carry out engineering analysis of the processes taking place in a separator. Hence, the three-dimensional coalescer was investigated as a porous element in order to find pressure losses dependence on flow velocity, which was required to simulate the existence of coalescers and baffles. As the next step, a transient Eulerian multiphase simulations were carried out for gas-oil-water mixture in a real horizontal gravity separator for two- and three-dimensional case. Required data for calculations was derived from real exploration well. In the two-dimensional case, the worked out dependence of the pressure drop with respect to velocity was used to model the flow through the porous coalescers. In three-dimensional case, the coalescers and baffles were modelled without any simplifications. It was found that general trends can be predicted despite the simplification of the geometrical model in which coalescer and baffle geometries have been replaced by a porous medium. The calculations confirmed that the complexity of geometry requiring time-consuming calculations can be usually replaced by introducing simplifications allowing for engineering analysis of separator operation that is acceptable by the industry, because the basic parameters regarding the separation process can be determined.805813Z.KrzemianowskiInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, PolandInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, Polandpayskrzemian@imp.gda.plM.LackowskiInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, PolandInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, Polandpaysmarcin.lackowski@imp.gda.plT.OchrymiukInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, PolandInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, Polandpaystomasz.ochrymiuk@imp.gda.plP.FlaszyńskiInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, PolandInstitute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, Gdańsk, 80-231, Polandpayspawel.flaszynski@imp.gda.plOil Separators Multiphase calculations Coalescers.[Abdulkadir, M. and V. H. Perez (2010). The effect of mixture velocity and droplet diameter on oil-water separator using computational fluid dynamics (CFD). World Academy of Science Engineering and Technology 61, 35-43.##
Arnold, K. and M. Stewart (2008). Surface production operations, Vol. 1: 3rd Edition, Design of oil-handling systems and facilities. Gulf Professional Publishing, USA. ##
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Yayla S., K. Kamal, and S. Bayraktar (2019). Numerical analysis of a two-phase flow (oil and gas) in a horizontal separator used in petroleum projects. Journal of Applied Fluid Mechanics 12(4), 1037-1045.##]Mitigation of Flow Maldistribution in Minichannel and Minigap Heat Exchangers by Introducing Threshold in Manifolds22In the present paper, a detailed numerical investigation has been carried out to analyze the flow maldistribution in 50 parallel rectangular cross-section (1 mm depth and 1 mm width) minichannels and minigap section (1 mm depth and 99 mm width) with rectangular/trapezoidal manifolds in Z-type flow configuration. The author carried out numerical investigation with various mass flow rates, namely 0.05 kg/s, 0.1 kg/s and 0.2 kg/s which results in Reynolds number of 1532, 3064, 6128 respectively. A novel approach for the mitigation of non-uniform flow has been proposed introducing threshold at the entrance of the minigeometry section. The conventional case without threshold (as reference) and 1 mm, 3 mm and 7 mm threshold were introduced. The threshold has been employed by making a manifolds’ depth bigger than section’s depth. The maldistribution coefficient can be reduced twice in minigap section or three times in the minichannel section already with the 1 mm threshold as compared to the arrangement without threshold. It is found that rectangular manifold gives lower maldistribution coefficient than trapezoidal manifold which corresponds with actual state of the art. The distribution is more uniform in minichannel section than in minigap section for the same inlet parameters. To obtain uniform distribution of fluid flow should be stabilized already at the inlet manifold, at the entrance to the minichannel or minigap section. That was done by introducing the threshold in the manifolds, which is novelty of this study.815826P.DąbrowskiGdańsk University of Technology, Gdańsk, Pomorskie, 80-233, PolandGdańsk University of Technology, Gdańsk, Pomorskie, 80-233, Polandpayspawel.dabrowski@pg.edu.plMinigeometry Flow distribution Manifold shape Manifold’s depth CFD Numerical study.[Alam, T., P. S. Lee, C. R. Yap and L. Jin (2013). A comparative study of flow boiling heat transfer and pressure drop characteristics in microgap and microchannel heat sink and an evaluation of microgap heat sink for hotspot mitigation. International Journal of Heat and Mass Transfer 58(1–2), 335–347.##
Amador, C., A. Gavriilidis and P. Angeli (2004). Flow distribution in different microreactor scale-out geometries and the effect of manufacturing tolerances and channel blockage. Chemical Engineering Journal 101(1–3), 379–390.##
Anbumeenakshi, C. and M. R. Thansekhar (2016). Experimental investigation of header shape and inlet configuration on flow maldistribution in microchannel. Experimental Thermal and Fluid Science 75, 156–161.##
Brutin, D., V. S. Ajaev and L. Tadrist (2013). Pressure drop and void fraction during flow boiling in rectangular minichannels in weightlessness. Applied Thermal Engineering 51(1–2), 1317–1327.##
Chien, N. B., N. X. Linh and O. Jong-Taek (2019). Numerical Optimization of Flow Distribution inside Inlet Header of Heat Exchanger. Energy Procedia 158, 5488–5493.##
Dąbrowski, P., M. Klugmann and D. Mikielewicz (2017). Selected studies of flow maldistribution in a minichannel plate heat exchanger. Archives of Thermodynamics 38(3), 135–148.##
Dąbrowski, P., M. Klugmann and D. Mikielewicz (2019). Channel Blockage and Flow Maldistribution during Unsteady Flow in a Model Microchannel Plate heat Exchanger. Journal of Applied Fluid Mechanics 12(4), 1023–1035.##
García-Cascales, J. R., F. Illán-Gómez, F. Hidalgo-Mompeán, F. A. Ramírez-Rivera and M. A. Ramírez-Basalo (2017). Performance comparison of an air/water heat pump using a minichannel coil as evaporator in replacement of a fin-and-tube heat exchanger. International Journal of Refrigeration 74, 558–573.##
Kumar, R., G. Singh and D. Mikielewicz (2018). A New Approach for the Mitigating of Flow Maldistribution in Parallel Microchannel Heat Sink. Journal of Heat Transfer 140(7), 72401–72410.##
Kumar, R., G. Singh and D. Mikielewicz (2019). Numerical Study on Mitigation of Flow Maldistribution in Parallel Microchannel Heat Sink: Channels Variable Width Versus Variable Height Approach. Journal of Electronic Packaging 141(2), 21009–21011.##
Kumar, S. and P. K. Singh (2019). Effects of flow inlet angle on flow maldistribution and thermal performance of water cooled mini-channel heat sink. International Journal of Thermal Sciences 138(February 2018), 504–511.##
Kumaraguruparan, G., R. M. Kumaran, T. Sornakumar and T. Sundararajan (2011). A numerical and experimental investigation of flow maldistribution in a micro-channel heat sink. International Communications in Heat and Mass Transfer 38(10), 1349–1353.##
Mathew, J., P. S. Lee, T. Wu and C. R. Yap (2019). Experimental study of flow boiling in a hybrid microchannel-microgap heat sink. International Journal of Heat and Mass Transfer 135, 1167–1191.##
Mikielewicz, D. and J. Mikielewicz (2010). A thermodynamic criterion for selection of working fluid for subcritical and supercritical domestic micro CHP. Applied Thermal Engineering 30(16), 2357–2362.##
Mu, Y. T., L. Chen, Y. L. He and W. Q. Tao (2015). Numerical study on temperature uniformity in a novel mini-channel heat sink with different flow field configurations. International Journal of Heat and Mass Transfer 85, 147–157.##
Najim, M. and M. B. Feddaoui (2018). New cooling approach using successive evaporation and condensation of a liquid film inside a vertical mini-channel. International Journal of Heat and Mass Transfer 122, 895–912.##
Sakamatapan, K. and S. Wongwises (2014). Pressure drop during condensation of R134a flowing inside a multiport minichannel. International Journal of Heat and Mass Transfer 75, 31–39.##
Shao, H., M. Zhang, Q. Zhao, Y. Wang and Z. Liang (2018). Study of improvements on fl ow maldistribution of double tube-passes shell- and-tube heat exchanger with rectangular header. Applied Thermal Engineering 144(January), 106–116.##
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]The Effect of Swirling Air-to-Liquid Momentum Ratio on the Spray and Droplet Characteristics22The effect of swirl flow on the spray characteristics (structure, droplet diameter and droplet velocity) is experimentally investigated for varying air-to-liquid momentum ratios in this work. The diagnostic techniques employed include high-speed shadowgraphy and 1D-PDPA. A commercial pressure swirl injector is mounted in a swirl stabilized model gas turbine burner to investigate the spray characteristics with and without the presence of swirling flowfield under isothermal conditions. In the absence of the injector flow the burner produced a converging-diverging flowfield at the burner exit, influenced by the bluffbody effect near to the exit and the swirling intensity farther downstream. The investigations reveal an unmistakable influence of the swirling flow on the droplet size, velocity and spatial distribution. Under the investigated momentum flux ratios the conical spray structure is altered and the droplets size and velocity at each location changed with the spatial variation in the magnitude and nature of the swirling flowfield. In general fine droplets are produced near to the high velocity air inflow, and coarser droplets in the recirculation zone owing to the longer residence time. The mean axial velocity of the droplet reduced in presence of swirling flow, with the droplets showing negative velocities at downstream locations.827837M.Chinnaraj Department of Aerospace Engineering, Indian Institute of Space Science and Technology (IIST), Thiruvananthapuram, Kerala, India - 695 547Department of Aerospace Engineering, Indian Institute of Space Science and Technology (IIST), Thiruvananthapuram, Kerala, India - 695 547paysmahenderanarun@gmail.comR.SadanandanDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology (IIST), Thiruvananthapuram, Kerala, India - 695 547Department of Aerospace Engineering, Indian Institute of Space Science and Technology (IIST), Thiruvananthapuram, Kerala, India - 695 547paysrajeshsadanandan@iist.ac.inSwirl flow Sprays SMD High-Speed shadowgraphy PDPA.[Aliseda, A., E. Hopfinger, J. Lasheras, D. Kremer, A. Berchielli, and E. Connolly (2008). Atomization of viscous and non-newtonian liquids by a coaxial, high-speed gas jet. experiments and droplet size modeling. International Journal of Multiphase Flow 34, 161–175.##
Charalampous, G., C. Hadjiyiannis, and Y. Hardalupas (2019). Proper orthogonal decomposition of primary breakup and spray in co-axial airblast atomizers. Physics of Fluids 31, 043304.##
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Fan, Y., N. Hashimoto, H. Nishida, and Y. Ozawa (2014). Spray characterization of an air-assist pressure-swirl atomizer injecting high-viscosity jatropha oils. Fuel 121, 271–283.##
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]Experimental Investigation on the Effects of Swirl on the Exit Turbulent Flow Field of an Unconfined Annular Burner at Isothermal and Reacting Conditions22The objective was to study the effect of change in swirl intensities, S=0.4, 0.7 & 1 of the annular swirling flow on the exit flow field of an unconfined annular swirl burner operated at isothermal (only dry air) and reacting flow (premixed methane air mixture) conditions. Reynolds number at the burner’s annular exit based on its hydraulic diameter (D) was kept constant at 4000. Exit flow field at isothermal conditions was measured using planar particle image Velocimetry rig and processed using commercial software. The percentage decay in the magnitude of peak value of axial velocity obtained from its radial profile at a height of 4D from the burner exit with the change in swirl intensity of 1, 0.7, 0.4 and 0 was 65%, 55%, 47.2% and 13.5%. The jet spreading angle was 6.5o for S=0, 8.4o for S=0.4, 9.8 for S= 0.7 and 14.2o for S=1. Recirculation zone was observed only for S=0.7 and 1.0. The width of the recirculation zone was 3D (S=0.7) and 3.4D (S=1) respectively. The normalized reverse mass flow rates estimated were 0.027 for S = 0.7 and 0.058 for S = 1.0. The magnitude of turbulence intensities at wake shear layer was much higher than the jet shear layer due to the presence of recirculation zones for S= 0.7 and 1.0. The integral length scales calculated were varied in the range of 0.06D0.18D for all swirl intensities. Reaction front was identified by deconvoluting the time mean OH* chemiluminescence using Abel inversion method. The flame became shorter and wider with increase in swirl number which was in consonance with the observation of increase in size of recirculation flow in the isothermal flow. The equivalence ratios at which the lean blow out observed were 0.58, 0.6 and 0.62 for S=0.4, 0.7 and 1.
839847R.ManikandanDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695547, IndiaDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695547, Indiapaysnewtonzerogravity@gmail.comR.SadanandanDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695547, IndiaDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695547, Indiapaysrajeshsadandan@iist.ac.inC.PrathapDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695547, IndiaDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695547, Indiapaysprathapc@iist.ac.inSwirling flow Axial swirl generator Jet spreading rate Chemiluminescence Lean blowout.[Abdel-Gayed, R. G. and D. Bradely (1981) A Two-Eddy Theory of Premixed Turbulent Flame Propagation. Philosophical Transactions of the Royal Society of London 301, 1-25##
Alekseenko, S. V., V. M. Dulin, Y. S. Kozorezov, D. M. Markovich, S. I. Shtor, M. P. Tokarev (2011) Flow structure of swirling turbulent propane flames. Flow Turbulence Combust 87, 569–595##
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]Transient Numerical Analysis of Natural Convection in Partially Open Cavities Filled with Water near the Density Inversion Point22A transient numerical analysis of natural convection of near-freezing water in a cavity with lateral openings and internal heat sources is carried out to investigate the influence of the heat dissipation rate in the flow configuration. The heat sources were positioned to create buoyancy-opposing and buoyancy-assisted conditions simultaneously and the top and bottom walls are kept at 0◦C. The non-linear dependence of the physical properties with temperature is considered in the governing equations. Based on the heat dissipation rate, six different regimes were observed and classified through a qualitative analysis of the temporal evolution of the velocity and temperature fields. The characteristics of heat transfer for each regime are analyzed to define the most important mechanisms of heat removal. In the upper layer (heated from below), the buoyancy forces eventually overcome the viscous forces and unsteady thermal plumes are formed, in-creasing the heat removal through the openings, while the heat transfer with the top wall is not significant. In the lower layer, the development of wave-like instabilities leads to oscillatory regimes for intermediate heat dissipation rates, while for high dissipation rates a steady convective regime is observed. This behavior increases the heat transfer with the bottom wall, making it much more significant when compared with the upper layer.849860E.FontanaFederal University of Paraná, Chemical Engineering Department, 82590-300, Curitiba, PR, BrazilFederal University of Paraná, Chemical Engineering Department, 82590-300, Curitiba, PR, Brazilpayseliton.fontana@ufpr.brC. A.CapelettoFederal University of Paraná, Chemical Engineering Department, 82590-300, Curitiba, PR, BrazilFederal University of Paraná, Chemical Engineering Department, 82590-300, Curitiba, PR, Brazilpaysclaudia.capeletto@ufpr.brA.da SilvaFederal University of Santa Catarina, Chemical and Food Engineering Department, 88040-970, Florianópolis, SC, BrazilFederal University of Santa Catarina, Chemical and Food Engineering Department, 88040-970, Florianópolis, SC, Brazilpaysadriano.silva@ufsc.brV. C.MarianiPontifical University Catholic, Mechanical Engineering Department, 80215-900, Curitiba, PR, BrazilPontifical University Catholic, Mechanical Engineering Department, 80215-900, Curitiba, PR, Brazilpaysviviana.mariani@pucpr.brCFD Analysis Hydrodynamic stability Density inversion Flow regimes.[Banaszek, J., Y. Jaluria, T. A. Kowalewski, and M. Rebow (1999). Semi-implicit FEM analysis of natural convection in freezing water. Numerical Heat Transfer, Part A 36, 449 – 472.##
Baudoin, A., D. Saury, and C. Bostrom (2017). Optimized distribution of a large number of power electronics components cooled by conjugate turbulent natural convection. Applied Thermal Engineering 124, 975 – 985.##
Duluc, M. C. and Y. C. Fraigneau (2017). Effect of frequency on natural convection flows induced by a pulsating line-heat source. International Journal of Thermal Sciences 117, 342 – 357.##
Ezan, M. A. and M. Kalfa (2016). Numerical investigation of transient natural convection heat transfer of freezing water in a square cavity. International Journal of Heat and Fluid Flow 61, 438 – 448.##
Fontana, E., A. Silva, and V. C. Mariani (2011). Natural convection in a partially open square cavity with internal heat source: An analysis of the opening mass flow. International Journal of Heat and Mass Transfer 54, 1369 – 1386.##
Fontana, E., C. A. Capeletto, A. Silva, and V. C. Mariani (2013). Three-dimensional analysis of natural convection in a partially-open cavity with internal heat source. International Journal of Heat and Mass Transfer 61, 525 – 542.##
Fontana, E., C. A. Capeletto, A. Silva, and V. C. Mariani (2015). Numerical analysis of mixed convection in partially open cavities heated from below. International Journal of Heat and Mass Transfer 81, 829 – 845.##
Hossain, M. A. and D. A. S. Rees (2005). Natural convection flow of water near its density maximum in a rectangular enclosure having isothermal walls with heat generation. Heat Mass Tran. 41, 367 – 374.##
Hu, Y. P., Y. R. Li, and C. M. Wu (2016). Aspect ratio dependence of Rayleigh-Be ́nard convection of cold water near its density maximum in vertical cylindrical containers. International Journal of Heat and Mass Transfer 97, 932 – 942.##
Hu, Y. P., Y. R. Li, C. M. Wu, S. Z. Li, and M. H. Li (2017a). Flow pattern and heat transfer in Rayleigh-Be ́nard convection of cold water near its density maximum in a rectangular cavity. International Journal of Heat and Mass Transfer 107, 1065 –1075.##
Hu, Y. P., Y. R. Li, M. H. Lai, L. Zhang, and S. Z. Li (2017b). Effects of enclosure geometry and thermal boundary condition on Rayleigh-Be ́nard convection of cold water near its maximum density. International Journal of Thermal Sciences 120, 220 – 232.##
Kumar, V., A. Srivastava, and S. Karagadde (2017). Real-time observations of density anomaly-driven convection and front instability during solidification of water. ASME Journal of Heat Transfer 140(40).##
Lemmon, E. W., M. O. McLinden, and D. G. Friend (2017). Thermophysical Properties of Fluid Systems. Gaithersburg MD: National Institute of Standards and Technology.##
Li, Y. R., Y. P. Hu, and X. F. Yuan (2013). Three-dimensional numerical simulation of natural convection of water near its density maxi-mum in a horizontal annulus. International Journal of Thermal Sciences 71, 274 – 282.##
Li, Y. R., Y. P. Hu, Y. Q. Ouyang, and C. M. Wu (2015). Flow state multiplicity in Rayleigh-Be ́nard convection of cold water with density maximum in a cylinder of aspect ratio 2. International Journal of Heat and Mass Transfer 86, 244 – 257.##
Lu, Y., Q. Yu, W. Du, and Y. Wu (2016). Natural convection heat transfer of molten salts around a vertically aligned horizontal cylinder set. International Communications in Heat and Mass Transfer 76, 147 – 155.##
Mastiani, M., M. M. Kim, and A. Nematollahi (2017). Density maximum effects on mixed convection in a square lid-driven enclosure filled with Cu-water nanofluids. Advanced Powder Technology 28, 197 – 214.##
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Mirzaie, M. and E. Lakzian (2006). Natural convection of Cu-water nanofluid near water density inversion in horizontal annulus with different arrangements of discrete heat source sink pair. Advanced Powder Technology 27, 1337 – 1346.##
Quintino, A., E. Rici, S. Grignaffini, and M. Corcione (2017). Heat transfer correlations for natural convection in inclined enclosures-filled with water around its density-inversion point. International Journal of Thermal Sciences 116, 310 – 319.##
Sharma, K. (2013). On thermodynamic analysis of substances with negative coefficient of thermal expansion. Engineering 5(11), 844 –849.##
Siavashi, M., V. Bordbar, and P. Rahnama (2017). Heat transfer and entropy generation study of non-Darcy double-diffusive natural convection in inclined porous enclosures with different source configurations. Applied Thermal Engineering 110, 1462 – 1475.##
Xu, H., H. H. Chen, S. Wang, Z. Li, K. Li, G. Stecker, W. Pan, J. J. Lee, and C. C. Chen (2017). Coupled natural convection and radiation heat transfer of hybrid solar energy conversion system. International Journal of Heat and Mass Transfer 107, 468 – 483.##
Yoon, J. I., C. G. Moon, E. Kim, Y. S. Son, J. D. Kim, and T. Kato (2001). Experimental study on freezing of water with supercooled region in a horizontal cylinder. Applied Thermal Engineering 21, 657 – 668.##
]Effect of Viscosities on the Spray Characteristics of Pressure Swirl Nozzle22The effects of medium viscosity on the spray flow rate, spray Sauter Mean Diameter, droplet velocity and spray cone angle of pressure swirl nozzles are investigated by making use of the particle dynamics analysis system and high-speed photographic system. Based on the axial and radial distribution characteristics of Sauter Mean Diameter and droplet velocity, the water-glycerol mixture is used to simulate medium with a wide range of viscosities. It is found that with the increase of viscosity, the turbulence of the medium flow and the swirling effect is weakened, and the rated pressure becomes larger and the spray flow rate increases. Spray Sauter Mean Diameter and droplet axial velocity becomes larger, while the spray cone angle decreases. The development of the axial velocity distribution of spray cone is characterized by the radial and axial position parameters. The area of the large-droplet region on both sides of spray cone becomes larger, and the area of small-droplet region near the axis becomes smaller.861870Z. M.LiuCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, ChinaCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, Chinapayslzm@bjut.edu.cnJ. Y.LinCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, ChinaCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, Chinapays849509620@qq.comH. L.ZhengCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, ChinaCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, Chinapayszhenghuilong@iet.cnlY.PangCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, ChinaCollege of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, Chinapayspangyan@bjut.edu.cnPDA system spray characteristics SMD Spray cone angle Medium viscosity.[Amini, G (2016) Liquid flow in a simplex swirl nozzle. International, Journal of Multiphase Flow 79, 225.##
Chen, L., Z. Liu, P. Sun and W. Huo (2015) Formulation of a fuel spray SMD model at atmospheric pressure using Design of Experiments (DoE), Fuel 153, 355-360.##
Chung, I. P., C. Presser (1998) Effect of fluid Viscosity and Surface Tension on Liquid Sheet Disintegration of a Simplex Pressure-Swirl Atomizer. Conference on Liquid Atomization and Spray Systems.##
Dafsari, R. A., H. J. Lee, J. Han, D. Park and J. Lee (2019) Viscosity effect on the pressure swirl atomization of an alternative aviation fuel, Fuel 240, 179-191##
Davanlou, A., J. D. Lee, S. Basu and R. Kumar (2015) Effect of viscosity and surface tension on breakup and coalescence of bicomponent sprays. Chemical Engineering Science 131, 243-255.##
Dopazo, C., J. Ballester (1994) Discharge Coefficient and Spray Angle Measurements for Small Pressure-Swirl Nozzles. Atomization & Sprays 4(3), 351-367.##
Durdina, L., J. Jedelsky, M. Jicha (2014) Investigation and comparison of spray characteristics of pressure-swirl atomizers for a small-sized aircraft turbine engine. International Journal of Heat & Mass Transfer 78(7), 892-900.##
Fan, Y., N. Hashimoto, H. Nishida and Y. Ozawa (2014) Spray characterization of an air-assist pressure-swirl atomizer injecting high-viscosity Jatropha oils, Fuel 121(2), 271-283.##
Fu, Q. F., L. J. Yang and Qu, Y. Y. (2011) Measurement of annular liquid film thickness in an open-end swirl injector. Aerospace Science & Technology 15(2), 117-124.##
García, J. A., J. L. Santolaya, A. Lozano, F. Barreras and E. Calvo (2016) Experimental characterization of the viscous liquid sprays generated by a Venturi-vortex atomizer. Chemical Engineering & Processing Process Intensification 105, 117-124.##
Hashimoto, N., H. Nishida, Y. Ozawa (2014) Fundamental combustion characteristics of Jatropha oil as alternative fuel for gas turbines. Fuel 126(126), 194-201.##
Kang, Z. T., Q. L. Li, X. Q. Zhang and P. Cheng (2014) Gas-liquid coaxial double centrifugal nozzle spray characteristics. Journal of National University of Defense Technology (5), 50-57.##
Kim, H., T. Ko, S. Kim and W. Yoon (2017) Spray characteristics of aluminized-gel fuels sprayed using pressure-swirl atomizer. Journal of Non-Newtonian Fluid Mechanics 249, 36-47##
Lee, E. J., Y. O. Sang, H. Y. Kim, S. C. James and S. S. Yoon (2010) Measuring air core characteristics of a pressure-swirl atomizer via a transparent acrylic nozzle at various Reynolds numbers. Experimental Thermal & Fluid Science 34(8), 1475-1483.##
Liu, C. X., F. Q. Liu, Y. H. Mao, Y. Mu and G. Xu (2013) Experimental study on fuel space distribution characteristics of centrifugal nozzles for a certain type of aero engine, Journal of Aerospace Power 28(4), 783-791.##
Liu, Z. M., K. F. Wang, Z. L. Wang, H. L. Zheng, T. Zhang and Z. Y. Kang (2018) Effect of stepped acceleration section on atomization characteristics of swirl nozzle. Chinese Journal of Theoretical and Applied Mechanics 50(3), 570-578.##
Liu, Z. M., Z. L. Wang, K. F. Wang, et al. (2018b) Influences of dorsal pressure difference on the atomization performance of a pressure swirl nozzle. Journal of Beijing University of Technology 44(8), 1063-1068.##
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Xie, J. L., Z. W. Gan, F. Duan, T.N. Wong, S.C.M. Yu and R. Zhao (2013) Characterization of spray atomization and heat transfer of pressure swirl nozzles, International Journal of Thermal Sciences 68, 94-102.##
Zhang, X. C., X. F. Wang (1989) Theoretical and Experimental Study on the Effect of Liquid Viscosity on Centrifugal Nozzle Spray Concentration Distribution and Spray Cone Angle. Journal of Propulsion Technology 10(6), 19-24.##
]Investigation of Air Flow Characteristics in Air Intake Hoses using CFD and Experimental Analysis based on Deformation of Rubber Hose Geometry22In this study, the pressure loss value of air intake hose of FIAT 1.3 E6D type engine, located between intercooler and inlet manifold of the engine, was examined using computational fluid dynamics, considering geometrical deformation in a rubber material. The rubber material modelling was performed by the verification of the data - obtained through the experimental method- with ANSYS software using Mooney-Rivlin method. The rubber material modelling was performed with the aim of correctly determination of the increase in the hose diameter when subjected to pressure, since the material has the feature of elasticity. In this study, ANSYS Fluent v.18.0 software and a static pressure machine were used. The air intake into the hose took place at the pressure of 123,5 kPa and flow rate of 0,087 kg/s. A solution, independent of the number of element, was obtained in the analysis. The turbulence model used in the study is standard k-ε type. As a result, the deformation-oriented pressure loss in the last geometry was found 1,85 kPa. The analyses were repeated for non-deformed geometry, and a pressure loss of 2,04 kPa was determined. At the result of the test, the geometry was seen to become actually deformed, and the pressure loss was found 1,9 kPa. The lowness of pressure loss in the deformed geometry was seen as the removal of the sharp bends that would cause local losses with the effect of pressure forces. In this study, it was determined that geometrical deformation changes the geometrical features that causes pressure loss, and leads to less pressure loss. 871880K. Furkan SokmenBursa Technical University, Faculty of Engineering and Natural Science, Mechanical Engineering Department, Bursa, 16330, TurkeyBursa Technical University, Faculty of Engineering and Natural Science, Mechanical Engineering Department, Bursa, 16330, Turkeypaysfurkan.sokmen@btu.edu.trO.Bedrettin KaratasBursa Technical University, Faculty of Engineering and Natural Science, Mechanical Engineering Department, Bursa, 16330, TurkeyBursa Technical University, Faculty of Engineering and Natural Science, Mechanical Engineering Department, Bursa, 16330, Turkeypaysosman.karatas@btu.edu.trAir intake hose Pressure drop Rubber material model Deformation Computational fluid dynamics.[Abdullah, N. R., N. S. Shahruddin, A. M. I. Mamat, S. Kasolang, A. Zulkifli and R. Mamat (2013). Effects of air intake pressure to the fuel economy and exhaust emissions on a small SI engine. Procedia Engineering 68, 278–284. ##
Baaser, H. (2007). Global optimization of length and macro-micro transition of fabric-reinforced elastomers with application to a brake hose. Computational Materials Science 39(1 SPEC. ISS.), 113–116.##
Bhakade, S., T. Ashta and S. Patil (2016). Deformation Analysis of Flexible Hose used in Air Intake System of Automobile using CFD and FEA, International Conference on Design, Manufacturing and Mechatronics, At Trinity College, Pune.##
Chaubey, A. and P. A. C. Tiwari (2017). Design and CFD Analysis of The Intake Manifold for the Suzuki G13bb Engine5(Vi), 1258–1276.##
Choi, H. and I. Oh, (2010). Analysis of product efficiency of hybrid vehicles and promotion policies. Energy Policy 38(5), 2262–2271. ##
Gohel, N. S. (2015). CFD Analysis of Air Intake System 4(2), 45–48.##
Gu, S. (2017). Application of finite element method in mechanical design of automotive parts. IOP Conference Series: Materials Science and Engineering, 231(1), 012180.##
Kamarulbaharin, Z. A. and S. Kasolang (2015). Flow behaviour analysis along an engine air intake pipe. Jurnal Teknologi, 76(10), 65–69. ##
Kumar, J. S. and V. Ganesan (2004). Flow through S.I. engine air intake system using CFD at part throttle and full throttle. Indian Journal of Engineering and Materials Sciences 11(2), 93–99.##
Kumar, N. and V. V. Rao (2016). Hyperelastic Mooney-Rivlin Model : Determination and Physical Interpretation of Material Constants. MIT International Journal of Mechanical Engineering 6(1), 43–46.##
Mamat, R., N. Rosli Abdullah, H. Xu, M. L. Wyszynski, and A. Tsolakis (2017). Effect of air intake pressure drop on performance and emissions of a diesel engine operating with biodiesel and ultra low sulphur diesel (ULSD). Renewable Energy and Power Quality 1(07), 787–794.##
Ramasamy, D., M. Zamri, S. Mahendran, and S. Vijayan (2010). Design Optimization of Air Intake System ( AIS ) of 1 . 6L Engine by Adding Guide Vane. The International MultiConference of Engineers and Computer Scientists (IMECS), Hong Kong.##
Rao, A. (2003). Fluid-solid interaction analysis using ANSYS/multiphysics. Computational Fluid and Solid Mechanics 2003, 1492–1496.##
Safwan, M. and B. A. Lothfy (2009). Pressure Drop analysis of 1.6 L car Air intake system, Doctoral dissertation, UMP.##
Satheeskumar, S. and G. Kanagaraj (2016). Experimental investigation on tribological behaviours of PA6, PA6-reinforced Al2O3and PA6-reinforced graphite polymer composites. Bulletin of Materials Science 39(6), 1467–1481. ##
Sedlacek, F. and M. Skovajsa (2016). Optimization of an Intake System Using CFD Numerical Simulation. Proceedings in Manufacturing Systems 11(2), 71–76.##
Uysal, A., M. Ozalp, A. Korgavus, and O. Korgavus (2012). Numerical modeling of the momentum and thermal characteristics of air flow in the intercooler connection hose. In International Journal of Advanced Manufacturing Technology 60, 811–824. ##
Williams, C. B. and R. Ilardo(2010). Design and manufacture of a Formula SAE intake system using fused deposition modeling and fiber-reinforced composite materials. Rapid Prototyping Journal 16(3), 174–179.##
Yerram, R., Prasad, N., Malathkar, P. R., Halbe, V., & Murthy, S. D. (2006). Optimization of Intake System and Filter of an Automobile using CFD analysis. Quality Engineering & Software Technologies (QUEST), Bangalore, India.##
]Design for a Squirrel Cage Fan with Double Arc Blade22Squirrel cage fans are commonly used in HVAC (heating, ventilation, and air conditioning) systems. The single arc blade model is commonly used in this type of fans since it can be shaped simply only by two parameters of inlet and outlet angle of blade. However, the efficiency of the fans is much lower than that we expected. In this paper, the single arc blade is replaced by double-arc blade in order to optimize the blade model and to improve the static pressure efficiency and total pressure efficiency of the fan. Numerical results show that the design with double arc blade is able to improve the internal flow, and to enhance the aerodynamic performance of squirrel cage fans.881891Z.LiFaculty of Aeronautical Engineering, Taizhou University, Taizhou, Zhejiang 318000, ChinaFaculty of Aeronautical Engineering, Taizhou University, Taizhou, Zhejiang 318000, Chinapays54840541@qq.comH. S.DouFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, ChinaFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, Chinapayshuashudou@yahoo.comP.LinFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, ChinaFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, Chinapayslinpf@zstu.edu.cnY.WeiFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, ChinaFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, Chinapaysykun_wei@sina.comY.ChenZhejiang Yilida Ventilator Co., Ltd., Taizhou, Zhejiang 318056, ChinaZhejiang Yilida Ventilator Co., Ltd., Taizhou, Zhejiang 318056, Chinapayscyn121@yilida.conL.LinZhejiang Yilida Ventilator Co., Ltd., Taizhou, Zhejiang 318056, ChinaZhejiang Yilida Ventilator Co., Ltd., Taizhou, Zhejiang 318056, Chinapayslinlimin@yilida.comX.YeFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, ChinaFaculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, Chinapaysyexinxue1025@qq.comDouble arc blade Optimization Squirrel cage fans.[Darvish, M., S. Frank, and O. Paschereit (2015). Numerical and Experimental Study on the Tonal Noise Generation of a Radial Fan, Journal of Turbomachinery 137(10), 1-9.##
Fernandez, O, P. García, and J. González (2013). Numerical Methodology for the Assessment of Relative and Absolute Deterministic Flow Structures in the Analysis of Impeller-Tongue Interactions for Centrifugal Fans, Computers & Fluids 86(7), 310-325.##
Kim, Y. and J. Seo (2004). Shape Optimization of Forward-Curved-Blade Centrifugal Fan with Navier-Stokes Analysis, Journal of Fluids Engineering 126(5), 735-742.##
Kind, J. (1997). Prediction of Flow Behavior and Performance of Squirrel-Cage Centrifugal Fans Operating at Medium and High Flow Rates, Journal of Fluids Engineering 119(3), 639-646.##
Kind, J. and G. Tobin (1990). Flow in a Centrifugal Fan of the Squirrel-Cage Type, Journal of Turbomachinery 112(1), 84-90.##
Rafael, T., C. Francisco, and S. Sandra (2009). Numerical Model for the Unsteady Flow Features of a Squirrel Cage Fan, American Society of Mechanical Engineers, 173-183.##
Suárez, V., B. Tajadura, and G. Pérez (2006). Numerical Simulation of the Unsteady Flow Patterns in a Small Squirrel-Cage Fan, American Society of Mechanical Engineers, 297-304.##
Tremmel, M. and D. Taulbee (2008). Calculation of the Time-Averaged Flow in Squirrel-Cage Blowers by Substituting Blades With Equivalent Forces, Journal of Turbomachinery 130(3), 538-544.##
Wen, X., D. Qi, and Y. Mao (2013). Experimental and Numerical Study on the Inlet Nozzle of a Small Squirrel-Cage Fan, Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 227(4), 450-463.##
Wen, X., Y. Mao, and X. Yang (2016). Design Method for the Volute Profile of a Squirrel-Cage Fan with Space Limitation, Journal of Turbomachinery 138(8), 1-13.##
]Stent Porosity Efficiency in Treating Wide-Neck Saccular Renal Artery Aneurysm22Renal arteries are the arteries that supply blood to the kidneys. Renal arteries are the arteries that supply blood to the kidneys. Renal artery aneurysm (RAA) is the second most common visceral aneurysm to occur, which accounts for 22% of the visceral aneurysm. In general population, RAA rate of occurrence was only 0.1%. However, due to the extensive used of angiography technique, RAA has been discovered more frequently. Some claimed that the previous rate of incidence should be higher now because of the capability of angiography. The rupture of this aneurysm could result in haemorrhage, kidney lost and mortality. The size of the renal artery which is different compared to other types of arteries such as the abdominal aorta could produce different flow condition when the artery is inflicted with RAA condition. Thus, a thorough analysis is desired as RAA studies are very limited compared to other aneurysm conditions. In this study, the efficiency of the stent porosity was investigated in treating the RAA. Fluid-structure interaction (FSI) simulations and particle image velocimetry (PIV) experiments were the approaches taken to investigate the flow patterns of the blood when the stent of different porosities was placed in the aneurysm entrance. The effect of wall shear stress (WSS), the deformation of the artery and von Mises stress were also observed in determining the possibility of aneurysm rupture. The study found that the placement of stent of different porosities succeeds in providing an obstruction to the blood from circulating inside the aneurysm sac. This in turns reduced the WSS experienced by the aneurysm sac up a significant value of 96%. This reduction is crucial in order to prevent the aneurysm from rupture. Moreover, the placement of the stent provided support to the renal artery and preventing it from experiencing buckling failure. The maximum deformation of the artery reduced by 42% with stent was placed in the renal artery. In fact, the von Mises stress decreased below the threshold limit of 0.5 MPa with the presence of the stent. In addition, the study found that the stent of porosity 80% has a similar impact to the stent of lower porosity in the case of RAA at main renal artery.893908H.Abu BakarSchool of Mechanical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, MalaysiaSchool of Mechanical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysiapayshaziqbakar@gmail.comA.AbasSchool of Mechanical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, MalaysiaSchool of Mechanical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysiapaysaizatabas@usm.myN.RazakSchool of Aerospace Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, MalaysiaSchool of Aerospace Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysiapaysnorizham@usm.myRenal artery aneurysm Porosity FSI PIV.[Aggarwal, S., A. Qamar, V. Sharma, and A. Sharma, (2011). Abdominal aortic aneurysm: A comprehensive review. Experimental and clinical cardiology 16(1), 11-15. ##
Aird, W. C. (2007). Vascular bed-specific thrombosis. Journal of Thrombosis and Haemostasis 5 Suppl 1, 283-291. ##
Alderazi, Y., D. Shastri, T. Kass-Hout, C. Prestigiacomo, and C. D. Gandhi, (2014). Flow Diverters for Intracranial Aneurysms. Stroke research and treatment.##
Azar, D., D. Ohadi, A. Rachev, J. F. Eberth, M. J. Uline, and T. Shazly, (2018). Mechanical and geometrical determinants of wall stress in abdominal aortic aneurysms: A computational study. PLOS ONE 13(2), e0192032. ##
Barros, K. J. F., P. B. Metzger, F. H. Rossi, T. O. Rodrigues, S. M. Moreira, , A. C. G. Petisco, A. M. Kambara, (2014). Techniques and Strategies for the Endovascular Treatment of Renal Artery Aneurysm. Revista Brasileira de Cardiologia Invasiva (English Edition), 22(1), 64-72. ##
Bracale, U. M., D. Narese, I. Ficarelli, M. De Laurentis, F. Spalla, E. Dinoto, G. Vitale, D. Solari, G. Bajardi and F. Pecoraro, (2017). Stent-assisted detachable coil embolization of wide-necked renal artery aneurysms. Diagnostic and Interventional Radiology 23(1), 77-80. ##
Brouillard, A. M., X. Sun, A. H. Siddiqui, and N. Lin, (2016). The Use of Flow Diversion for the Treatment of Intracranial Aneurysms: Expansion of Indications. Cureus 8(1), e472.##
Canchi, T., S. D. Kumar, E. Y. K. Ng, and S. Narayanan, (2015). A Review of Computational Methods to Predict the Risk of Rupture of Abdominal Aortic Aneurysms. BioMed Research International 2015, 1-12. ##
Canton, G., D. I. Levy, J. C. Lasheras, and P. K. Nelson, (2005). Flow changes caused by the sequential placement of stents across the neck of sidewall cerebral aneurysms. Journal of Neurosurg 103(5), 891-902.##
Canyiğit, M., Çam A., Çetin H., Altunoğlu A., and M., Hıdıroğlu (2015). The use of the Cardiatis multilayer flow modulator stent to treat sequential saccular aneurysms of the renal artery in a solitary kidney. . turkish journal of thoracic and cardiovascular surgery (23), 354-358. ##
Chandra, V., B. W. Ullery, and J. T. Lee, (2014). Endovascular Stent-Graft Repair of Proximal Renal Artery Aneurysms. Journal of Vascular Surgery 60(2), 546-547.##
Coleman, D. M., and J. C. Stanley, (2015). Renal artery aneurysms. Journal of Vascular Surgery 62(3), 779-785. ##
Di Martino, E. S., A. Bohra, J. P. Vande Geest, Gupta, M. S. Makaroun, and D. A. Vorp, (2006). Biomechanical properties of ruptured versus electively repaired abdominal aortic aneurysm wall tissue. Journal of Vascular Surgery 43(3), 570-576. ##
Drewe, C. J., L. P. Parker, L. J. Kelsey, P. E. Norman, J. T. Powell, and B. J. Doyle, (2017). Haemodynamics and stresses in abdominal aortic aneurysms: A fluid-structure interaction study into the effect of proximal neck and iliac bifurcation angle. Journal of Biomechanics, 60 (Supplement C), 150-156. ##
Du, Y., and C. Lü, (2017). Modeling on monitoring the growth and rupture assessment of saccular aneurysms. Theoretical and Applied Mechanics Letters 7(2), 117-120. ##
Eskandari, M. K., and S. A. Resnick, (2005). Aneurysms of the Renal Artery. Seminars in Vascular Surgery 18(4), 202-208. ##
Farotto, D., P. Segers, B. Meuris, J. Vander Sloten, and N. Famaey, (2018). The role of biomechanics in aortic aneurysm management: requirements, open problems and future prospects. Journal of the Mechanical Behavior of Biomedical Materials, 77 (Supplement C), 295-307. ##
Gates, L., and J. E. Indes, (2017). renal artery aneurysm treatment and management. Retrieved from https://emedicine.medscape .com/article/463015-treatment##
Giannoglou, G., G. Giannakoulas, J. Soulis, Y. Chatzizisis, T. Perdikides, N. Melas, N., Parcharidis, G. Louridas, (2006). Predicting the Risk of Rupture of Abdominal Aortic Aneurysms by Utilizing Various Geometrical Parameters: Revisiting the Diameter Criterion. Angiology 57(4), 487-494. ##
Hoi Yiemeng , Hui Meng, Scott H. Woodward, Bernard R. Bendok, Ricardo A. Hanel, Lee R. Guterman and L. Nelson Hopkins. (2004). Effects of arterial geometry on aneurysm growth: three-dimensional computational fluid dynamics study. Journal of Neurosurgery 101(4), 676-681. ##
Hwang, P. F., D. C. Rice, S. V. Patel, D. Mukherjee, (2011). Successful management of renal artery aneurysm rupture after cesarean section. Journal of Vascular Surgery 54(2), 519-521.##
Javadzadegan, A., B. Fakhim, M. Behnia, and M. Behnia, (2014). Fluid-structure interaction investigation of spiral flow in a model of abdominal aortic aneurysm. European Journal of Mechanics - B/Fluids 46 (Supplement C), 109-117. ##
Klausner, J. Q., P. F. Lawrence, M. P. Harlander-Locke, D. M. Coleman, J. C. Stanley, and N. Fujimura, (2015). The contemporary management of renal artery aneurysms. Journal of Vascular Surgery 61(4), 978-984.e971.##
Kulcsar, Z., L. Augsburger, P. Reymond, V. M. Pereira, S. Hirsch, A. S. Mallik, S. G.Wetzel, I. Wanke, D. A. Rufenacht, (2012). Flow diversion treatment: intra-aneurismal blood flow velocity and WSS reduction are parameters to predict aneurysm thrombosis. Acta Neurochir (Wien) 154(10), 1827-1834. ##
Lin, S., X. Han, Y. Bi, S. Ju, and L. Gu, (2017a). Fluid-Structure Interaction in Abdominal Aortic Aneurysm. BioMed Research International 2017, 10. ##
Lin, S., X. Han, Y. Bi, S. Ju, and L. Gu, (2017b). Fluid-Structure Interaction in Abdominal Aortic Aneurysm: Effect of Modeling Techniques. BioMed Research International 2017, 10.##
Maughan, E., C. Webster, T. Konig, and I. Renfrew, (2015). Endovascular management of renal artery aneurysm rupture in pregnancy – A case report. International Journal of Surgery Case Reports 12, 41-43. ##
Meng, H., Z. Wang, M. Kim, R. D. Ecker, and L. N. Hopkins, (2006). Saccular aneurysms on straight and curved vessels are subject to different hemodynamics: implications of intravascular stenting. AJNR. American journal of neuroradiology 27(9), 1861-1865. ##
Mokhtar, N. H., A. Abas, N. A. Razak, M. N. A. Hamid, and S. L. Teong, (2017). Effect of different stent configurations using Lattice Boltzmann method and particles image velocimetry on artery bifurcation aneurysm problem. Journal of Theoretical Biology 433, 73-84. ##
Mokhtar, N. H., A. Abas, S. L. Teong, and N. A. Razak (2016). Particle image velocimetry experiment of blood flow through stent in artery bifurcation aneurysm problem. AIP Conference Proceedings 1775(1), 030095. ##
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Raschi, M., F. Mut, G. Byrne, C. M. Putman, S. Tateshima, F. Viñuela, T. Tanoue, K. Tanishita and J. R. Cebral, (2012). CFD and PIV Analysis of Hemodynamics in a Growing Intracranial Aneurysm. International Journal for Numerical Methods in Biomedical Engineering 28(2), 214-228. ##
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Sisto, A., A. L. Restante, B. A. Brik, and L. Preziosi, (2015, 19-21 Nov. 2015). Numerical simulation comparison between monolayer and Multilayer Flow Modulator in a cerebral saccular aneurysm. Paper presented at the 2015 E-Health and Bioengineering Conference (EHB).##
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Suess, T., J. Anderson, L. Danielson, K. Pohlson, T. Remund, E. Blears, S. Gent and P. Kelly (2016). Examination of near-wall hemodynamic parameters in the renal bridging stent of various stent graft configurations for repairing visceral branched aortic aneurysms. Journal of Vascular Surgery, 64(3), 788-796. ##
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Wang, Y., S. Song, G. Zhou, D. Liu, X. Xia, B. Liang, C. Zheng and G. Feng, (2018). Strategy of endovascular treatment for renal artery aneurysms. Clinical Radiology 73(4), 414.e411-414.e415. ##
]Michell’s Thin Ship Theory in Optimisation of Warp-Chine on Pentamaran Configuration22This study was conducted to optimise warp–chine pentamaran conﬁgurations in wave cancellations to a significant total resistance reduction for a wide range of speed. The optimisation of a pentamaran with a warp–chine hull form was performed by a computer program Godzilla based on Michell's theory and validated by the towing test. The distance parameters of the outrigger were evaluated to select the lowest resistance generated. Computational analysis depended on the Michell–based tool compared to a commercial Computational Fluid Dynamics (CFD). The comparison of the measurement test of the total resistance and Michell's calculation results of all configurations showed a suitable trend, especially at Fn ≥ 0.4. However, it was not satisfactory for CFD trend. The illustrated of far-field wave pattern by the Michell-based instrument also consistent with the wave spectrum that captured in the test. The results of the analysis and observations revealed that the test measurement for all configuration models in the same estimated error (uncertainty) range of the total resistance. This optimisation has confirmed the stagger at the range of 0.36L–0.42L where the front outriggers and the after outriggers not in line of clearance as in arrow formation significant in wave cancellation and resistance reduction. 909921W.SulistyawatiDepartment of Mechanical Engineering, Universitas Indonesia, Depok, Jawa Barat 16425, IndonesiaDepartment of Mechanical Engineering, Universitas Indonesia, Depok, Jawa Barat 16425, Indonesiapaysw12n_sby@yahoo.com.YanuarDepartment of Mechanical Engineering, Universitas Indonesia, Depok, Jawa Barat 16425, IndonesiaDepartment of Mechanical Engineering, Universitas Indonesia, Depok, Jawa Barat 16425, Indonesiapaysyanuar@eng.ui.ac.idA. S.PamitranDepartment of Mechanical Engineering, Universitas Indonesia, Depok, Jawa Barat 16425, IndonesiaDepartment of Mechanical Engineering, Universitas Indonesia, Depok, Jawa Barat 16425, Indonesiapayspamitran@eng.ui.ac.idPentamaran Warp–chine Michell’s theory Optimisation Wave cancellation Resistance reduction.[Aubault, A., and R. W. Yeung (2012). Interference resistance of multi-hull vessels in ﬁnite-depth waters. Journal of Marine Systems and Ocean Technology 7 (2), 107-116.##
Bari, G. S., and I. M. Konstantin (2016). Hydrodynamic modelling of planning catamarans with symmetric hulls. Ocean Engineering 115, 60-66. ##
Begovic, E., and C. Bertorello (2012). Resistance assessment of warped hull form. Ocean Engineering 56, 28–42.##
Begovic, E., Bertorello, C., Caldarella and P. Cassella (2004). Pentamaran hull for medium-size fast ferries, In Chang and Yeow’s (Eds.), Hydrodynamics VI: theory and applications, 23–27.##
Blount, D. L. (1995, September). Factors influencing the selection of a hard chine or round-bilge hull for high Froude numbers. In C.F.L. Kruppa (Ed.), Proceed¬ings of the 3th International Conference on Fast Sea Transportation, Lubeck-Travemunde, Germany. 1 (3), 18.##
Brizzolara, S., D. Bruzzone, and E. Tincani (2005, June). Automatic optimisation of a trimaran hull form configuration. Proceed¬ings of the 8th International Conference on Fast Sea Transportation, Saint Petersburg, Russia, 49–56.##
Chengyi, W. (1994). Resistance characteristic of high-speed catamaran and its application. Ship building of China 3, 28-39.##
Day, A. H., and L. J. Doctors (2001). Rapid estimation of near- and far-field wave from ships and application to hull form design and optimization. Journal of Ship Research 45, 73–84.##
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]Numerical Characterization of Natural Swirling Flame Evolving in Free Environment via FDS: a Comprehensive Investigation of Fires Problems22In this paper, a numerical study of a swirling flame generated through the interaction between a central fire and its surrounding fires is performed. A swirling flame can be configured by installing a secondary’s sources surrounding the central source, organized in an asymmetrical manner in order to ensure circumferential entrainment of the central flame by the supply puffs air. An analysis is performed to study this kind of flow. This analysis highlights the different zones that characterize the vertical propagation of a swirling flame; a first zone, close to the fire source, characterized by an acceleration of the flow and an increase of the temperature. A second zone marked by the passage of the temperature by a maximum while changing variation with a net decrease of the flow acceleration and a third zone where the thermal and dynamic fields change and gradually decrease. Moreover, this study shows an axisymmetric flow behavior with two different aspects of its global structure. A central region characterized by a block motion (solid core) where the flow is rotational, characterized by a concentration of vorticity, and surrounded by the rest of the space where the flow is irrotational. Moving vertically away from the active source, results show an attenuation of the axial vortex intensity which is accompanied by a disappearance of movement by block. The centerline evolution of the axial and azimuthal momentum flux enables also to highlight these different aspects of the global flow structure.923934M.Al. ThamriUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, TunisiaUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, Tunisiapaysthamrimedali@gmail.comT.NaffoutiUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, TunisiaUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, Tunisiapaystaoufiknaffouti@gmail.comS.GannouniUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, TunisiaUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, Tunisiapaysgannounisoufien@gmail.comJ.ZinoubiUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, TunisiaUniversity of Tunis El-Manar, Faculty of Sciences of Tunis, Department of Physics, Laboratory of Energizing and Thermal and Mass Transfer, 2092, El-Manar, Tunis, Tunisiapaysjamil.zinoubi@ipeiem.utm.tnSwirling flame Solid core Vorticity Rankine vortex Model Momentum flux Swirl number.[Beér, J. M. and N. A. Chigier (1972). Combustion Aerodynamics, Applied Science Publishers (Elsevier) Ltd., London, in the USA, Wiley Publishing Co, p. 265. ##
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Eldrainy, Y. A., H. S. Aly, K. M. Saqr and M. N. M. Jaafar (2009). A Multiple Inlet Swirler for Gas Turbine Combustors. Proc. of The International Conference on Fluid Mechanics, Heat Transfer and Thermodynamics, World Academy of Science, Engineering and Technology Tokyo, Japan,.##
Gao, W., N. Liu, Y. Jiao, X. Xie, Y. Pan, Z. Li, X. Luo, L. Zhang and T. Ran (2018). Flame length of non-buoyant turbulent slot flame, Proceedings of the Combustion Institute 37, 3843-3850.##
Gustenyov, N., N. K. Akafuah, A. Salaimeh, M. Finney, S. McAllister and K. Saito (2018). Scaling nonreactive cross flow over a heated plate to simulate forest fires, Combust. Flame 197, 340-354.##
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]Universal Method for Determination of Leakage in Labyrinth Seal22This paper presents calculation model enabling determination of the leakage rate in labyrinth seals. Described model is based on the Saint-Venant equation. It includes a new type of flow coefficient, which was determined based on experimental tests and described depending on the Reynolds number and the radial clearance. The structure of this calculation model can be applied to determine the leakage rate in straight through, staggered labyrinth seals as well as with various number of clearances. This model enables determining distribution of thermodynamic and flow parameters of the gas along the seal length. Results obtained from this model were next compared with experimental data for various types of seals. It enabled determination of kinetic energy carry-over coefficient in geometries under investigation. The value of this coefficient was then compared with the value of the coefficient from the Scharrer’s, Neumann’s and Hodkinson’s models. Obtained results indicate that the value of the kinetic energy carry-over coefficient depends not only on the seal geometry, but also on the pressure decrease.935943D.JoachimmiakChair of Thermal Engineering, Poznan University of Technology, Poznań, 60-965 PoznańChair of Thermal Engineering, Poznan University of Technology, Poznań, 60-965 Poznańpaysdamian.joachimiak@put.poznan.plLabyrinth seal Leakage Calculation model Experiment Flow coefficient Kinetic energy carry-over.[Asako, Y., K. Nakayama, and T. Shinozuka. (2005). Effect of Compressibility on Gaseous Flows in a Micro-Tube. International Journal of Heat and Mass Transfer 48(23–24),4985–94.##
Asok, S. P., K. Sankaranarayanasamy, T. Sundararajan, K. Rajesh, and G. Sankar Ganeshan (2007). Neural Network and CFD-Based Optimisation of Square Cavity and Curved Cavity Static Labyrinth Seals. Tribology International 40(7),1204–16.##
Childs, Dara W. and J. K. Scharrer (1986). An Iwatsubo-Based Solution for Labyrinth Seals: Comparison to Experimental Results. Journal of Engineering for Gas Turbines and Power 108(2),325–31.##
Dereli, Yilmaz and Dursun Eser (2004). Flow Calculations in Straight-through Labyrinth Seals by Using Moody’s Friction-Factor Model. Mathematical and Computational Applications 9(3),435–42.##
Egli, Adolf. (1935). The Leakage of Steam through Labyrinth Seals. Trans. ASME 57,115–22.##
Hodkinson, B. (1939). Estimation of the Leakage through a Labyrinth Gland. Proceedings of the Institution of Mechanical Engineers 141(1),283–88.##
Hong, C., Y. Asako, K. Suzuki, and M. Faghri. (2012). Friction Factor Correlations for Compressible Gaseous Flow in a Concentric Micro Annular Tube. Numerical Heat Transfer; Part A: Applications 61(3),163–79.##
Hu, D., L. Jia, and L. Yang. (2014). Dimensional Analysis on Resistance Characteristics of Labyrinth Seals. Journal of Thermal Science 23(6),516–22.##
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Joachimiak, Damian and Piotr Krzyślak (2017). “Experimental Research and CFD Calculations Based Investigations Into Gas Flow in a Short Segment of a Heavily Worn Straight Through Labyrinth Seal. Polish Maritime Research 24(2),83–88.##
Joachimiak, Damian and Piotr Krzyślak (2019). The Analysis of the Gas Flow in a Labyrinth Seal of Variable Pitch. Journal of Applied Fluid Mechanics 12(4).##
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Szymanski, Artur, Wlodzimierz Wróblewski, Daniel Fraczek, Krzysztof Bochon, Slawomir Dykas, and Krzysztof Marugi. (2018). “Optimization of the Straight-Through Labyrinth Seal With a Smooth Land.” Journal of Engineering for Gas Turbines and Power 140(12),122503.##
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Yuan, Haomin, Sandeep Pidaparti, Mathew Wolf, John Edlebeck, and Mark Anderson. (2015). “Numerical Modeling of Supercritical Carbon Dioxide Flow in See-through Labyrinth Seals. Nuclear Engineering and Design 293,436–46.##
Zhang, Wan Fu, Jian Gang Yang, Chun Li, and Yong Wei Tian. (2014). Comparison of Leakage Performance and Fluid-Induced Force of Turbine Tip Labyrinth Seal and a New Kind of Radial Annular Seal. Computers and Fluids 105,125–37.##
Zhirong, Lin, Wang Xudong, Yuan Xin, Shibukawa Naoki, and Noguchi Taro. (2015). Investigation and Improvement of the Staggered Labyrinth Seal. Chinese Journal of Mechanical Engineering 28(2),402–8.##
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]Effect of Hydraulic Resistivity on a Weakly Nonlinear Thermal Flow in a Porous Layer22Heat and mass transfer through porous media has been a topic of research interest because of its importance in various applications. The flow system in porous media is modelled by a set of partial differential equations. The momentum equation which is derived from Darcy’s law contains a resistivity parameter. We investigate the effect of hydraulic resistivity on a weakly nonlinear thermal flow in a horizontal porous layer. The present study is a realistic study of nonlinear convection flow with variable resistivity whose rate of variation is arbitrary in general. This is a first step for considering more general problems in applications that involve variable resistivity that may include both variations in permeability and viscosity of the porous layer. Such problems are important for understanding properties of underground flow, migration of moisture in fibrous insulations, underground disposal of nuclear waste, welding process, petrochemical generation, drug delivery in vascular tumor, etc. Using weakly non-linear procedure, the linear and first-order systems are derived. The critical Rayleigh number and the critical wave number are obtained from the linear system using the normal mode approach for the two-dimensional case. The linear and first-order systems are solved numerically using the fourth-order Runge-Kutta and shooting methods. Numerical results for the temperature are presented in tabular and graphical forms for different resistivities. Through this study, it is observed that a stabilizing effect on the dependent variables occurs in the case of a positive vertical rate of change in resistivity, whereas a destabilizing effect is noticed in the case of a negative vertical rate of change in resistivity. The results obtained indicate that the convective flow due to the buoyancy force is more effective for weaker resistivity.945955D.BhattaThe University of Texas Rio Grande Valley, Edinburg, TX, USA, 78539The University of Texas Rio Grande Valley, Edinburg, TX, USA, 78539paysdambaru.bhatta@utrgv.eduD. N.RiahiThe University of Texas Rio Grande Valley, Brownsville, TX, USA, 78520The University of Texas Rio Grande Valley, Brownsville, TX, USA, 78520paysdaniel.riahi@utrgv.eduHydraulic resistivity Weakly nonlinear Hydro-thermal Convective flow Rayleigh number.[Aldoss, T. K. (2009). Natural convection from a horizontal annulus filled with porous medium of variable permeability. Journal of Porous Media 12, 715-724.##
Bhatta, D. and D. N. Riahi (2017). Convective flow in an aquifer layer. Fluids 52, 1-19.##
Bhatta, D., D. N. Riahi and M. S. Muddamallappa (2010). On nonlinear evolution of convective flow in an active mushy layer. Journal of Engineering Mathematics 82, 385-399.##
Bhatta, D., M. S. Muddamallappa and D. N. Riahi (2012). Magnetic and permeability effects on a weakly nonlinear magneto-convective flow in an active mushy layer. International Journal Fluid Mechanics Research 39, 494-520.##
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Dejam, M. (2018). Dispersion in non-Newtonian fluid flows in a conduit with porous walls. Chemical Engineering Science 189, 296-310.##
Dejam, M. (2019a). Derivation of dispersion coefficient in an electro-osmotic flow of a viscoelastic fluid through a porous-walled micro-channel. Chemical Engineering Science 204, 298-309.##
Dejam, M. (2019b). Advective-diffusive-reactive solute transport due to non-Newtonian fluid flows in a fracture surrounded by a tight porous medium. International Journal of Heat and Mass Transfer 128, 1307-1321.##
Dejam, M. (2019c). Hydrodynamic dispersion due to a variety of flow velocity profiles in a porous-walled microfluidic channel. International Journal of Heat and Mass Transfer 136, 87-98.##
Falsaperla, P., G. Mulone and B. Straughan (2010). Modal package convection in a porous layer with boundary imperfections, International Journal of Engineering Science 48, 685-692.##
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Gangadharaiah, Y. H. (2016). Onset of Benard- Marangoni Convection in a Composite Layer with Anisotropic Porous Material. Journal of Applied Fluid Mechanics 9(3), 1551-1558.##
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Wang, Y., X. Xia, Y. Wang, L. Wang and W. Hu (2017). Using proper orthogonal decomposition to solve heat transfer process in a flat tube bank fin heat exchanger. Adv. Geo-energ. Res. 1 (3), 158-170.##
]Effect of Different Flow Directions on Drag over Riblet22Variation in flow direction requires extensive consideration in the practical application of riblet surfaces. However, studies scarcely examine the impact of flow angle α for riblet, which is usually adopted to reduce flow drag. Accordingly, this research conducted large eddy simulation for a wide range of flow angles. We explored the effect of 0° to 90° flow angle on the surface drag change of triangular riblet. The time-averaged statistical data and instantaneous flow details indicated that skin friction is decreased with the increase in α. However, pressure drag increased much faster than the friction decrease. Result revealed that skin friction reduction by 4.537% is obtained when α=0°, and it inhibits turbulence in the spanwise direction. When α≈20°, the total drag reduction disappeared. Within this range, the deviation angle showed little influence on the total drag reduction. When α=90°, skin friction is reduced by 73.3%; however the pressure drag and total drag increased, accompanied by an increased turbulence. The flow must be nearly parallel to the riblet to achieve drag reduction. Otherwise, the transverse riblet is an effective method to increase the drag.957967J.WangKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR ChinaKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR Chinapays1242280275@qq.comX.RenKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR ChinaKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR Chinapaysrxd@mail.tsinghua.edu.cnX.LiKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR ChinaKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR Chinapaysxs-li@mail.tsinghua.edu.cnC.GuKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR ChinaKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, PR Chinapaysgcw@mail.tsinghua.edu.cnM.ZhangInstitute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100084, PR ChinaInstitute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100084, PR Chinapaysmmzhang@iet.cnFlow angle Friction drag Pressure drag Triangular riblet.[Aupoix B. , Pailhas G. and Houdeville, R. (2012) . Towards a general strategy to model riblet effects, AIAA Journal 50 (3), 708-716.##
Bechert, D. W., Bruse, M., Hage, W. and Meyer, R. (2000). Fluid mechanics of biological surfaces and their technological application, Naturwissenschaften 87 (4), 157-171. ##
Bechert, D. W., & Bartenwerfer, M. (1989). The viscous flow on surfaces with longitudinal ribs, Journal of Fluid Mechanics 206(-1), 105.##
Bechert, D. W., Bruse, M., Hage, W., Vander Hoeven, J. G. T. and Hoppe, G. (1997). Experiments on drag-reducing surfaces and their optimization with an adjustable geometry, Journal of Fluid Mechanics 338, 59-87.##
Bechert, D. W., Bertenwerfer, M., Hoppe, G. and Reif W.-E. (1986). Drag reduction mechanisms derived from shark skin, American Institute of Aeronautics and Astronautics 2, 1044.##
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]Numerical Study on a Novel Type of High Gravity Rotary Gas-Liquid Separator22In textile printing and dyeing industry, a novel type of separator called high gravity rotary gas-liquid separator (HGRGS) is designed, which includes a rotary drum with multi-layer fins and an impeller. First, the structure and separation principle of HGRGS are introduced in this paper. Then, the flow field and separation efficiency are studied by CFD techniques. To ensure the accuracy of the numerical simulation, the results are verified by the available experimental data. Compared with the typical cyclone, the maximum pressure drop reduction rate in HGRGS is 64.7% when the gas enters at 10 m/s. Besides, for droplets less than 5 μm, the separation performance in HGRGS is more efficient and it will be greatly improved by 30% for 1 μm droplets. The numerical results also show that the tangential velocity inside the rotary drum is linear with the radius and the higher the rotating speed, the greater the tangential velocity. Moreover, the maximum tangential velocity between the forced and quasi-free vortex has moved to the vicinity of the outer wall, which is beneficial for droplets to move outward. Additionally, the droplets in HGRGS can be captured with enough residence time owing to the lower axial velocity than that in a typical cyclone.969979Z.ZhangSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, ChinaSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, Chinapayszhangzhen29301x@163.comH.WangSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, ChinaSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, Chinapays1201150119@njtech.edu.cnJ.MaSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, ChinaSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, Chinapaysjiema@njtech.edu.cnX.LingSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, ChinaSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu, 211816, Chinapaysxling@njtech.edu.cnHigh gravity Gas-liquid separator Rotary drum Pressure drop Separation efficiency Simulation. [Brar, L. S., R. P. Sharma and R. Dwivedi (2015). Effect of Vortex Finder Diameter on Flow Field and Collection Efficiency of Cyclone Separators. Particulate Science and Technology 33(1), 34-40.##
Brouwers, J. J. H. (2002). Phase separation in centrifugal fields with emphasis on the rotational particle separator. Experimental Thermal and Fluid Science 26(2), 325-334.##
Chen, S., P. Liu and J. Gong (2017). Performance study of backflow type dynamic cyclone separator for coalbed methane. Powder Technology 305, 56-62.##
Cortes, C. and A. Gil (2007). Modeling the gas and particle flow inside cyclone separators. Progress in Energy and Combustion Science 33(5), 409-452.##
Cui, J., X. Chen and X. Gong (2010). Numerical Study of Gas−Solid Flow in a Radial-Inlet Structure Cyclone Separator. Industrial & Engineering Chemistry Research 49(11), 5450-5460.##
de Souza, F. J., S. R. de Vasconcelos and M. D. A. de Moro (2012). Large Eddy Simulation of the gas–particle flow in cyclone separators. Separation and Purification Technology 94, 61-70.##
Gao, S., D. Zhang and Y. Fan (2018). Separation Performance in a Novel Coupled Cyclone with Built-in Circulating Granular Bed Filter (C-CGBF). Industrial & Engineering Chemistry Research 57(36), 12192-12201.##
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Huang, L., S. Deng and Z. Chen (2018). Numerical analysis of a novel gas-liquid pre-separation cyclone. Separation and Purification Technology 194, 470-479.##
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]A Study on the Effects of EGR and VNT on the Intake and Exhaust Pressure Waves in a High-Pressure Common-Rail Diesel Engine22The transient pressure waves in the intake and exhaust systems directly affect the intake and exhaust processes of diesel engines, thus further affecting the combustion process and the performance of diesel engines. The variation rules of the intake and exhaust pressure waves at different engine speeds and loads in a high-pressure common-rail diesel engine were studied. Then, the effects of EGR rate and VNT nozzle opening on the intake and exhaust pressure waves were systematically studied by bench test and one-dimensional simulation analysis. The results show that at 2000 r·min-1 full-load, when the EGR rate increases from 0 to 10%, the average intake pressure and the average exhaust pressure both decrease. The fluctuation waveforms of the intake pressure and the exhaust pressure change significantly. The fluctuation intensity of the intake pressure decreases by 58.6%, and the fluctuation intensity of the exhaust pressure increases by 77.2%. As the EGR rate increases from 10% to 30%, the average intake pressure and the average exhaust pressure both decrease. The fluctuation waveforms are basically unchanged. The increasing magnitudes of the intake and exhaust pressure fluctuation intensities are 16.6% and 20.5%, respectively. As the VNT nozzle opening increases, the average intake pressure and the average exhaust pressure both decrease. The corresponding phases of the intake pressure wave crest and trough are delayed. The fluctuation waveforms of the intake and exhaust pressure are basically unchanged, and the fluctuation intensities do not change significantly.981991S. H.LiuYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, ChinaYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, Chinapaysliushaohua183@126.comY. F.HouYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, ChinaYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, Chinapays1627148502@qq.comY. H.BiYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, ChinaYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, Chinapays815569621@qq.comS.YinYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, ChinaYunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650500, Chinapays724465575@qq.comHigh-pressure common-rail diesel engine Intake pressure wave Exhaust pressure wave EGR VNT.[Arnold, S. and M. Groskreutz (2002). Advanced Variable Geometry Turbocharger for Diesel Engine Applications. SAE Technical Paper 2002,01-0161.##
Changwei, J., Z. Yong and M. Hui (2006). Design and Experimental Study for Exhaust Pipes of Pressure Wave Supercharged Diesel Engine. Acta Armamentarii 27(3), 385-389. ##
Chiara, F., M. Canova, W. Yueyun (2011). An exhaust manifold pressure estimator for a two-stage turbocharged diesel engine. American Control Conference 2011:1549-1554.##
Huijie, L., B. Yuhua and S. Lizhong (2016). Exhaust pressure fluctuations and the influence factors study of two cylinders turbocharged inter-cooled diesel engine. Journal of Machine Design 33(6),30-35.##
Jimin, L., G. Xvnan and S. Xiuyong (2016). Study on the Development of Diesel Engine VNT-vEGR System Based on Multi-objective Optimization. Journal of Mechanical Engineering 52(2),108-115.##
Jinke, G., and G. Qingwu (2013). A Study on the Analysis and Design of Exhaust Manifold in a Four-cylinder Diesel Engine. Automotive Engineering 35(4),354-357.##
Jun, Z., W. Zhaoming and C. Yi (2011). Experimental Study on Variation Rules of Exhaust Pressure Wave for Turbocharged Six-Cylinder Diesel Engine. Chinese Internal Combustion Engine Engineering 32(2), 28-32,38. ##
Langridge, S.，H. Fessler (2002). Strategies for High EGR Rates in a Diesel Engine. SAE Technical Papers 2002,01-0961.##
Pischinger S.，J. Schnitzler，M. Rottmann (2002), Future of Combustion Engines. SAE Technical Papers 2006,21-0024.##
Qiwei, W., N. Jimin and C. Hong (2016). Study on the Effects of Venturi-EGR System on Turbo-charged Diesel Engine Performance. Journal of Mechanical Engineering 52(4),157-164.##
Tianling, W., L. Jun and W. Junhua (2006). Synergic effec,ts of EGR and VNT on exhaust emissions from turbocharged diesel engine. journal of jilin university (engineering and technology edition) 36(4),493-496.##
Wahlström, J. and L. Eriksson (2010). Nonlinear Input Transformation for EGR and VGT Control in Diesel Engines. SAE Technical Paper 2010,01-2203.##
Wei, D., L. Fushui and L. Zhijie (2008). Experimental Study on Fluctuation of Intake Pressure in Turbocharged Diesel Engine. Chinese Internal Combustion Engine Engineering 29(3),37-40. ##
Wenbin, W., L. Shaohua and B. Yuhua (2016). Simulation Study on Effect of EGR and VNT on Diesel Engine Performance for Plateau Environment. Small Internal Combustion Engine and Motorcycle 45(6),6-11.##
Wijetunge, R. S., J. G. Hawley and N.D. Vaughan (2004). Application of Alternative EGR and VGT Strategies to a Diesel Engine. SAE Technical Paper 2004, 01-0899.##
Wuqiang, S., Y. Shenghua (2011). Simulation and Analysis of Engine Intake System Performance Based on AVL- BOOST Software. International Combustion Engines (3),16-18.##
Xinghai, W., X. Chengning and N. Zhi (2007). The Effect of Exhaust Pressure Wave on the Performance of Diesel Engines. Diesel Engine 29(5),13-17.##
Xuewen, Z., S. Lizhong and B. Yuhua L. Jilin and W. Guiyong (2012). Study on Turbocharger Performance Matching for Two-Cylinder High Pressure Common Rail Diesel Engine. Chinese Internal Combustion Engine Engineering 33(1),11-17.##
Yang, Z., W. Zhong and X. Guangju (2016). The Effects of Exhaust Gas Recirculation on the Volatilization and Oxidation Characteristics of Particles from Diesel Engine. Automotive Engineering 38(8),935-940.##
Yongzhong, Y., S. Lizhong and B. Yuhua (2018). Effects of Atmospheric Pressure/VNT/EGR on Performance and Emissions of a Vehicle Diesel Engine. Chinese Internal Combustion Engine Engineering 39(3).##
Zamboni, G. (2018). A Study on Combustion Parameters in an Automotive Turbocharged Diesel Engine. Energies 11(10).##]Experimental and Numerical Investigation of Friction Coefficient and Wear Volume in the Mixed-Film Lubrication Regime with ZnO Nano-Particle22One of the most important challenges industry has always been facing is the wear phenomenon. Wear is the cause of huge deteriorations in parts and results in a drop in performance and lifetime of different machines. Therefore, finding solutions to reduce friction coefficient and wear is of special importance. The present research aims at numerical and experimental investigation of friction coefficient and wear in the presence of nano-lubricants. In the numerical section, to tackle different scales of contact components, two sub-models are developed. In the first one, contact of asperities is modeled and the properties of contact surfaces are taken into account. Second sub-model simulates nano-particles in the contact region. Furthermore, a series of experiments are conducted under different loads, speeds, and different values for Zinc Oxide nano-particle weight percent using a pin-on-disk test rig. Results show that predicted friction coefficient and wear volume in theory are reasonably in agreement with experimental results. It was found that adding nanoparticle to the lubricant can be beneficial in terms of friction reduction.9931001R.GholamiDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, IranDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iranpaysshirin.asal77@gmail.comH.Ghaemi KashaniDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, IranDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iranpayshosein.ghaemi@me.iut.ac.irM.SilaniDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, IranDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iranpayssilani@cc.iut.ac.irS.AkbarzadehDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, IranDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iranpayss.akbarzadeh@cc.iut.ac.irZinc oxide nano-particle Pin-on-disk test Nano-lubricant Wear Friction coefficient.[Akbarzadeh, S., and M. M. Khonsari. (2011). Experimental and theoretical investigation of running-in. Tribology International, 44(2), 92-100.##
Akbarzadeh, S., and M. M. Khonsari. (2016). On the Applicability of Miner’s Rule to Adhesive Wear. Tribology Letters, 63(2), 29.##
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]Implications of Velocity Ratio on the Characteristics of a Circular Synthetic Jet Flush Mounted on a Torpedo Model in Quiescent and Cross-Flow Conditions22A high velocity ratio synthetic jet on an arched surface is of great interest for its potential applications in navy, including torpedo. However, in spite of detailed research on synthetic jets over a flat surface in cross-flow, very few observations have been made on synthetic jets over a surface which is shaped like a torpedo. This study experimentally explores a synthetic jet mounted on a torpedo shaped model in quiescent and cross-flow conditions. Initially, the synthetic jet is characterized for two different diaphragm displacements and at four distinct actuation frequencies in the range of 1 Hz – 6 Hz in a quiescent flow environment. Subsequently, in cross flow, similar study is conducted for three cross-flow velocities ranging from 7.2 – 32 cm/s, at a fixed amplitude of diaphragm oscillations. The measurements are carried out using Laser Induced Fluorescence (LIF) and Laser Doppler Velocimetry (LDV) and the qualitative LIF visualizations are corroborated by the quantitative LDV data. These results indicate that the synthetic jet vortex rings can be grouped as stretched vortex rings and distorted tilted vortex rings. The flow structures primarily depend on the velocity ratio, which is function of cross-flow velocity and frequency of actuation. The flow physics in case of a curved torpedo surface is slightly different as compared to the synthetic jet on a flat surface.10031013A.KumarDepartment of Mechanical Engineering, School of Engineering, University of Petroleum and Energy Studies, Energy Acres, Bidholi, Dehradun, Uttarakhand, India 248007Department of Mechanical Engineering, School of Engineering, University of Petroleum and Energy Studies, Energy Acres, Bidholi, Dehradun, Uttarakhand, India 248007paysabhay.kumar@ddn.upes.ac.inA. K.SahaDepartment of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India 208016Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India 208016paysaksah@iitk.ac.inP. K.PanigrahiDepartment of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India 208016Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India 208016payspani@iitk.ac.inA.KarnDepartment of Mechanical Engineering, School of Engineering, University of Petroleum and Energy Studies, Energy Acres, Bidholi, Dehradun, Uttarakhand, India 248007Department of Mechanical Engineering, School of Engineering, University of Petroleum and Energy Studies, Energy Acres, Bidholi, Dehradun, Uttarakhand, India 248007paysakarn@ddn.upes.ac.inSynthetic jet Torpedo model Vortex rings Velocity ratio Jet in cross flow LIF.[Amitay, M., D.R. Smith, V. Kibens, D.E. Parekh and A. Glezer (2001). Modification of the Aerodynamics Characteristics of an Unconventional Airfoil Using Synthetic Jet Actuators. AIAA Journal 39(3), pp. 361- 370.##
Berk, T., N. Hutchins, I. Marusic, and B. Ganapathisubramani (2018). Trajectory of a synthetic jet issuing into high-Reynolds-number turbulent boundary layers. Journal of Fluid Mechanics 856, 531-551.##
Chaudhari, M., B. Puranik and A. Agrawal (2010). Effect of orifice shape in synthetic jet based impingement cooling. Experimental Thermal and Fluid Science 34, 246-256.##
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Wen, X., Y. Liu., and H. Tang (2018). Near-field interaction of an inclined jet with a crossflow: LIF visualization and TR-PIV measurement. Journal of Visualization 21(1), 19-38.##]Analytical Solutions for Unsteady Pipe Flows with Slip Boundary Condition22In this paper analytical expressions for time-dependent velocity proﬁles and pressure gradient are obtained for fully-developed laminar ﬂows with given volume ﬂow-rate conditions in circular pipe ﬂows with slip boundary conditions. The governing equations are solved analytically using the traditional Laplace transform method together with Mellin’s inversion formula. The evolution of velocity proﬁles and pressure gradient for starting and pulsatile ﬂow with slip boundary conditions are analyzed. New simpliﬁed expressions and perspectives on velocity and pressure gradient for no-slip and slip ﬂows are obtained from the analytical results. New scalings in starting and pulsatile ﬂows are proposed for pipe ﬂows with no-slip and slip boundary conditions using non-dimensional numbers. Special attention is paid to the effect of slip factor and pulsatile ﬂow frequency on the time-dependent skin-friction factor. Finally, by using the starting and pulsating ﬂow results, analytical expressions of velocity and pressure for arbitrary inﬂow are obtained by approximating the arbitrary volume ﬂow-rate by a Fourier series10151026Anek. V.PillaiDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram 695547, Kerala, IndiaDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram 695547, Kerala, Indiapaysanek1405@gmail.comK. V.ManuDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram 695547, Kerala, IndiaDepartment of Aerospace Engineering, Indian Institute of Space Science and Technology, Thiruvananthapuram 695547, Kerala, Indiapaysgvrmanu00@gmail.comMicropipe Starting flow Pulsatile flow Womersley number.[Avramenko, A., A. Tyrinov, and I. Shevchuk (2015). An analytical and numerical study on the start-up ﬂow of slightly rareﬁed gases in a parallel-plate channel and a pipe. Physics of Fluids 27(4), 042001.##
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]Resistance Force on a Spherical Intruder in Fluidized Bed22Insertion of large objects or intruders into granular material is common both in nature and industrial applications. During penetration due to collision between intruder and granular particles, intruder experiences resistance or drag force (analogy from fluid). In literature, it is extensively studied that in dry packed beds granular drag force increases with the intrusion depth. However, nearly no information is available about the effect of fluidization on the granular drag force and is the main theme of this paper. In this paper, discrete element method (DEM) and computational fluid dynamics (CFD) is used for performing numerical simulations. Simulations showed that granular drag force becomes independent of intrusion depth at incipient fluidization and is a function of Reynolds number. Using the mathematical relation of fluid drag force, granular viscosity of the fluidized bed is calculated. The physics for the fluid like state of granular material and the independence of granular drag force with intrusion depth is explained at the end of paper. 10271035A. A.ZaidiSchool of Mechanical and Manufacturing Engineering, National University of Sciences & Technology H-12, Islamabad, 44000, PakistanSchool of Mechanical and Manufacturing Engineering, National University of Sciences & Technology H-12, Islamabad, 44000, Pakistanpaysali.zaidi@smme.nust.edu.pkResistance force Fluidized bed Intruder impact Granular viscosity Discrete element method.[Jaeger, H. M., S. R. Nagel, and R. P.Behringer (1996). Granular solids, liquids, and gases. Reviews of Modern Physics 68(4), 1259-1273.##
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Nirmala, G., and L. Muruganandam (2015). An Experimental Study of Liquid-Solid Flow in a Circulating Fluidized Bed of Varying Liquid Viscosity. Journal of Applied Fluid Mechanics 8(1).##
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Zaidi, A. A. (2018). Particle velocity distributions and velocity fluctuations of non-Brownian settling particles by particle-resolved direct numerical simulation. Physical Review E 98(5), 053103.##
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Zaidi, A. A. (2018). Particle resolved direct numerical simulation of free settling particles for the study of effects of momentum response time on drag force. Powder Technology 335, 222-234.##
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]Effect of Interface Momentum Distribution on the Stability in a Porous-Fluid System22We numerically investigate the linear instability problem of Poiseuille flow in a channel partially filled with a porous medium on the bottom side. We are primarily interested in the influence of the interface momentum distribution including stress continuity and jump interface conditions. A spectral collocation method is applied in solving the fully coupled instability problem arising from the adjacent porous and free channel flows. The results show that the “interface stress coefficient” in a negative range has a larger effect on the trajectory of the eigenvalues than that in the positive range, especially the most unstable mode. Moreover, with a low permeability in the porous region, the interface momentum distribution has less effect on the stability of core flow. And when the “interface stress coefficient” is equal to its minimum negative value, the flow passing through the channel is at its most stable state. If the “interface stress coefficient” varies in a positive range, the degree of fluid stability is predicted to slightly diminish due to stress continuity condition at the interface.10371046P.HuSchool of Energy and Power Engineering, Northeast Electric Power University, Jilin 132012, PR ChinaSchool of Energy and Power Engineering, Northeast Electric Power University, Jilin 132012, PR Chinapayshupengfei@neepu.edu.cnQ.LiSchool of Energy and Power Engineering, Northeast Electric Power University, Jilin 132012, PR ChinaSchool of Energy and Power Engineering, Northeast Electric Power University, Jilin 132012, PR Chinapaysliqi_1015@163.comPorous layer Linear stability Interface momentum distribution Poiseuille flow.[Avramenko, A. A., A. V. Kuznetsov, B. I. Basok and D. G.Blinov (2005). Investigation of stability of a laminar flow in a parallel-plate channel filled with a fluid saturated porous medium. Physics of Fluids 17(9), 094102.##
Barletta, A. (2016). Instability of stationary two-dimensional mixed convection across a vertical porous layer. Physics of Fluids 28(1), 014101##
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Chang, M., F. Chen, B. Straughan (2006). Instability of Poiseuille flow in a fluid overlying a porous layer. Journal of Fluid Mechanics 564, 287-303.##
Coronado, M. and Jetzabeth J. Ramírez-Sabag (2008). Analytical model for tracer transport in reservoirs having a conductive geological fault. Journal of Petroleum Science & Engineering 62(3-4), 73-79.##
Dai, C., Q. Li, H. Lei (2015). Instability of Poiseuille flow in a channel filled with multilayer porous media. Journal of Porous Media 18, 165-177.##
Hanspal, N. S., A. N. Waghode, V. Nassehi and R. J. Wakeman (2006). Numerical Analysis of Coupled Stokes/Darcy Flows in Industrial Filtrations. Transport in Porous Media 64(1), 73-101.##
Li, Q., H. Y. Lei, C. S. Dai (2014). Linear stability of a fluid channel with a porous layer in the center. Acta Mechanica Sinica 30, 28-36.##
Liu, R., Q. S. Liu, S. C. Zhao (2008). Instability of plane Poiseuille flow in a fluid-porous system. Physics of Fluids 20(10), 104105.##
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]Numerical Study of Water Vapor Injection in the Combustion Chamber to Reduce Gas Turbine Fuel Consumption22In this study, the effect of water vapor injection on the flow pattern, temperature contamination and emission of pollutants has been studied. Also, the impact of the spray angle on the axis has been investigated and finally, the effect of fuel type and geometry on the flow variables has been investigated. The results were compared with numerical simulations performed by other researchers and the results showed that they are qualitatively acceptable. The purpose of this work is to investigate the effect of the amount of water vapor on flame and NOx released from combustion. The results showed that with the percentage of water injected, there were significant changes in the temperature and pressure contour patterns of the combustion chamber. The results showed that with the percentage of water injected, there were significant changes in the temperature and pressure contour patterns of the combustion chamber. The results showed that the overall efficiency of the Brighton cycle can be increased in the non-injecting mode from 91% to 95% for the combustion chamber mode by injecting 8% water vapor. Also, an increase of more than 8% of water vapor will not have much effect on efficiency of gas turbine and reduce fuel consumption.10471054R.SharafodiniDepartment of Mechanical Engineering, Tehran Gharb branch, Islamic Azad University, Tehran, IranDepartment of Mechanical Engineering, Tehran Gharb branch, Islamic Azad University, Tehran, Iranpaysreihanesharafi@yahoo.comM. R.HabibiEnergy Technologies Research Division, Research Institute of Petroleum Industry (RIPI), Tehran, IranEnergy Technologies Research Division, Research Institute of Petroleum Industry (RIPI), Tehran, Iranpayshabibimr@ripi.irM.PirmohammadiDepartment of Mechanical Engineering, Pardis Branch, Islamic Azad University, Pardis, IranDepartment of Mechanical Engineering, Pardis Branch, Islamic Azad University, Pardis, Iranpayspirmohamadi@pardisiau.ac.irCombustion chamber Water vapor injection Pollution release Hexane Fluent Computational fluid dynamics.[Almeida, A. L. M. de Soto, R. M. Laranjeira, Luís M. Pacheco Monteiro, A. dos Santos and E. Caetano Fernandes, 1D model for a low NOx ejector-pump like burner. Experimental Thermal and Fluid Science 100 (2019) 171–192##
Amani, E., M. R. Akbari and S. Shahpouri (2018). Multi-objective CFD optimizations of water spray injection in gas-turbine Combustors. Fuel 227, 267–278.##
Asgari, B. and E. Amani (2017). A multi-objective CFD optimization of liquid fuel spray injection in dry-low-emission gas-turbine combustors. Applied Energy 203 696–710##
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