20181110295Effect of Solvent Contribution on Thermally Developing Flow of FENE-P Fluids between Parallel Plates22Numerical computation of thermally developing laminar flow of viscoelastic FENE-P fluids flowing between two stationary parallel plates is investigated using the finite element technique. The influence of the effect of the solvent contribution as well as the fluid rheology on the flow field and heat transfer enhancement is investigated for the case of imposed constant wall heat flux and neglected viscous dissipation. Numerical results for flow field are compared first against available analytical solutions with and without inclusion of the solvent contribution. The obtained results for the viscoelastic case show that increasing Weissenberg number (We) leads to an increase in Nusselt number (Nu) while high values of the extensibility parameter (L2) decrease the Nusselt number. Fully developed Nusselt number values for FENE-P fluids flowing between two fixed parallel plates are obtained for several values of polymer concentration and the study confirms quantitatively that polymer concentration enhances heat transfer rates in FENE-P fluids.19A.FilaliChemical Engineering Department, Imperial College London, London, UKChemical Engineering Department, Imperial College London, London, UKpaysf.abdelkader@ic.ac.ukL.KhezzarMechanical Engineering Department, The Petroleum Institute – A part of Khalifa University of Science and Technology, Abu Dhabi, United Arab EmiratesMechanical Engineering Department, The Petroleum Institute – A part of Khalifa University of Science and Technology, Abu Dhabi, United Arab Emiratespayslkhezzar@pi.ac.aeM.AlshehhiLEAP, Mechanical Engineering Department, Université des Frères Mentouri, Constantine, AlgeriaLEAP, Mechanical Engineering Department, Université des Frères Mentouri, Constantine, Algeriapaysmalshehhi@pi.ac.aeZ.NemouchiLEAP, Mechanical Engineering Department, Université des Frères Mentouri, Constantine, AlgeriaLEAP, Mechanical Engineering Department, Université des Frères Mentouri, Constantine, Algeriapaysz.nemouchi@gmail.com2D Thermally developing flow Rheology FENE-P model Solvent contribution Nusselt number.[Bird, R. B., C. F. Curtiss, R. C. Armstrong and O. Hassager (1987). Dynamics of Polymeric Liquids Kinetic Theory 2, second ed., Wiley, New York. ##
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]Effect of Separation Angle and Nozzle Radial Position on Mixing Time in Ladles with Two Nozzles22Chemical, thermal and mechanical homogenization of both slag and steel during the ladle furnace process depends on the design of the gas injection system in gas bottom stirred ladles. In the past, a large number of variables have been investigated, nevertheless due to the importance of the slag layer during the process, it has been incorporated in water modeling studies in more recent investigations. In large industrial size ladles is common to use two porous plugs. The configuration of the injection system with two porous plugs requires optimization of both nozzle radial position and nozzle separation angle. In this work the effect of nozzle radial position, nozzle separation angle, gas flow rate and slag thickness on mixing time has been investigated using a water model. The effect of tracer concentration on mixing time was also explored. It is shown that a separation angle of 60 degrees provides the best mixing efficiency.1120A. S.GómezMorelia Technological Institute, Morelia, Mich, 58120, MexicoMorelia Technological Institute, Morelia, Mich, 58120, Mexicopaysalexis_gosa@hotmail.comA. N.ConejoMorelia Technological Institute, Morelia, Mich, 58120, MexicoMorelia Technological Institute, Morelia, Mich, 58120, Mexicopaysanconejo@gmail.comV. R.ZenitInstitute of Materials Research, UNAM, Coyoacan 04510, Mexico City, MexicoInstitute of Materials Research, UNAM, Coyoacan 04510, Mexico City, Mexicopayszenit@unam.mxWater model Mixing phenomena Ladle furnace Slag layer.[Amaro Villeda, A., M. Ramirez Argaez and A. Conejo (2014). Effect of slag properties on mixing phenomena in gas stirred ladles by physical modeling. ISIJ Int, 54, 1.##
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Borovoy, V. Y., V. Mosharov, V. Radchenko, A. Skuratov and I. Struminskaya (2014). Leading edge bluntness effect on the flow in a model air-inlet. Fluid Dynamics 49(4), 454–467.##
Das, S. and J. Prasad (2010a). Starting characteristics of a rectangular supersonic air-intake with cowl deflection. The aeronautical journal 114(1153), 177–189.##
Das, S. and J. Prasad (2010b). Unstart suppression and performance analysis of supersonic air-intake adopting bleed and cowl bending. IE (I) Journal–AS 91, 27–35.##
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]Effects of Reinjection on Flow Field of Open Jet Automotive Wind Tunnel Test Section22The distributions of axial static pressure coefficient and flow fluctuation in the test section which affect aerodynamic measurement in an open jet wind tunnel is presented. In this paper, the flow characteristics of the open jet automotive wind tunnel with passive reinjection and active reinjection were simultaneously investigated by experimental and numerical approaches. The axial static pressure coefficient variations can be reduced by passive or active reinjection, and recycle flow returns to the test section from the loophole is the main reason. The more mass flow rate improves the effect. Meanwhile, it is found that the improvement of the axial static pressure coefficient by reinjection is always better in the condition of 0° collector angle. The turbulence intensity in the collector angle of 15° is lower than that of 0°, and the reinjection increases the turbulence intensity near the collector. The increase of the turbulence intensity by active reinjection in the collector angle of 0° is greater than the collector angle of 15° for the 3.28° diffusion angle. There are some peaks emerging at the frequencies of 40 Hz and 50 Hz, which indicates that the flow field fluctuations may have induced structural vibration. The peaks at several frequencies increase when the passive and active reinjection are conducted, and the increase of peak is correlate with the increase of the reinjection flow rate. Due to the reduction of average static pressure coefficient and increase of flow fluctuations, the application of passive and active reinjection should be considered at the same time.4353Q.LiShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, ChinaShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, Chinapaysqiliang.li@sawtc.comW.DaiShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, ChinaShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, Chinapays1074666340@qq.comL.ZhongShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, ChinaShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, Chinapaysphilip_zhong@foxmail.comZ.YangShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, ChinaShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, Chinapayszhigang.yang@sawtc.comK.DuShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, ChinaShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, Chinapays1538349053@qq.comY.XuShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, ChinaShanghai Automotive Wind Tunnel Center, Tongji University, Shanghai, Chinapaysxuyudong89@gmail.comM. M.RashidiDepartment of Civil Engineering, School of Engineering, University of Birmingham, Birmingham, UKDepartment of Civil Engineering, School of Engineering, University of Birmingham, Birmingham, UKpaysmm_rashidi@yahoo.comOpen jet automotive wind tunnel Axial static pressure coefficient Turbulence intensity Velocity and pressure fluctuations.[Amandolese, X. and C. Vartanian (2010). Reduction of 3/4 open jet low-frequency fluctuations in the S2A wind tunnel. Journal of Wind Engineering and Industrial Aerodynamics 98(10-11), 568-574.##
Bergmann, D., U. Kaiser and S. Wagner (2008). Reduction of low-frequency pressure fluctuations in wind tunnels. Journal of Wind Engineering and Industrial Aerodynamics 91(4), 543-550.##
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]Shielding Gas Coaxial Jet Pipes Numerical Study of a Vertical Laser Welding Process of AZ91 Magnesium Alloy22The laser welding of magnesium alloys, largely used in many fabrication applications, has gained considerable interest especially in aerospace, electronics, automotive industry etc. Unfortunately, this process is associated to an undesired phenomenon which is “oxidation”. For this reason, a good shielding system of the welding zone is of major importance. This paper presents a numerical study using computational fluid dynamics (CFD) of a laser welding process employing a moving volumetric heat source. Starting with the turbulence model validity, a parametric study of this welding process in a vertical position aiming to optimize the design of protection gas device, the gas jet inclination, the appropriate welding direction and the gas type is, then, proposed. The optimum parametric combination ensuring the largest gas coverage area is the one where the shielding gas is Argon, supplied by the coaxial nozzles at a downward inclination angle with respect to the laser beam axis, and a downward welding direction.7994C.BoughanmiUTTPI, Thermodynamics and Thermal Unit Industrial Process (UTTPI) Ecole Nationale d’Ingénieurs de Monastir ENIM, 5000 Monastir, TunisiaUTTPI, Thermodynamics and Thermal Unit Industrial Process (UTTPI) Ecole Nationale d’Ingénieurs de Monastir ENIM, 5000 Monastir, Tunisiapayschiraz.boughanmi@gmail.comS.BannourUTTPI, Thermodynamics and Thermal Unit Industrial Process (UTTPI) Ecole Nationale d’Ingénieurs de Monastir ENIM, 5000 Monastir, TunisiaUTTPI, Thermodynamics and Thermal Unit Industrial Process (UTTPI) Ecole Nationale d’Ingénieurs de Monastir ENIM, 5000 Monastir, Tunisiapayssana_bannour@yahoo.frH.MhiriUTTPI, Thermodynamics and Thermal Unit Industrial Process (UTTPI) Ecole Nationale d’Ingénieurs de Monastir ENIM, 5000 Monastir, TunisiaUTTPI, Thermodynamics and Thermal Unit Industrial Process (UTTPI) Ecole Nationale d’Ingénieurs de Monastir ENIM, 5000 Monastir, Tunisiapaysha.mhiri@gmail.comP.BournotIUSTI, Technopole of Château-Gombert, 5 city Enrico Fermi, 13013 Marseille, FranceIUSTI, Technopole of Château-Gombert, 5 city Enrico Fermi, 13013 Marseille, Francepaysbournotphilippe@gmail.comLaser welding Shielding gas Coaxial impinging jet Numerical study Volume fraction. [Abderrazak, K., S. Bannour, H. Mhiri and G. Lepalec, M. Autric (2009). Numerical and experimental study of molten pool formation during continuous laser welding of AZ91magnesium alloy. Comput. Mater. Sci. 44(3), 858–66.##
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Yokoharaa, K., Y. Okamotoa, A. Okadaa, H. Ochiaib, R. Kimurab and M. Akase (2016). Investigation of shielding gas supplying method in vertical-position laser welding of pure titanium. Procedia CIRP 42, 448–53.##]Numerical Visualization of Plunging Water Jet using Volume of Fluid Model22A plunging liquid jet is defined as a moving column of liquid passing through a gaseous headspace, air in our case, before impinging a free surface of receiving liquid pool. The mechanism of air entrainment due to plunging liquid jets is very complex and the complete mechanism of air entrainment is not fully understood so far. The present paper is an unsteady numerical simulation of air entrainment by water jet plunging, using the Volume Of Fluid (VOF) model. The piece wise linear interface construction algorithm (PLIC) for interface tracking is used, to describe the phase distributions of entirely immiscible air and liquid phases. The aim of this work is to investigate the performance and accuracy of the VOF method in predicting the initial impact between the descending jet and water free surface, air entrainment and the developing flow region under free surface. Three scale models based on geometric similarities (Froude number and dimensionless free jet length) are used for validation according to Chanson (2004) experience. The simulations show with accuracy, the air cavity formation steps, caused by the initial jet impact, its deep stretching under the pool free surface, until breakdown due to the shear created by a toroidal vortex. In terms of, air entrainment estimation, bubble dispersion and radial distribution of air volume fraction, large-scale models present a good agreement with the experience. However, for the smallest scale model, the results lead to suggest that air entrainment is governed by more parameters than the geometric similarities. 95105A.BoualouacheDepartment of Mechanical Engineering, Faculty of Technology, University of A. Mira Bejaia, 06000, Bejaia, Algeria.Department of Mechanical Engineering, Faculty of Technology, University of A. Mira Bejaia, 06000, Bejaia, Algeria.paysamine.boualouache@univ-bejaia.dzF.ZidouniLaboratory of Theoretical and Applied Fluid Mechanics , Faculty of Physics, University of Science and Technology Houari Boumediene - USTHB, Algiers, AlgeriaLaboratory of Theoretical and Applied Fluid Mechanics , Faculty of Physics, University of Science and Technology Houari Boumediene - USTHB, Algiers, Algeriapaysfzidouni@usthb.dzA.MataouiLaboratory of Theoretical and Applied Fluid Mechanics , Faculty of Physics, University of Science and Technology Houari Boumediene - USTHB, Algiers, AlgeriaLaboratory of Theoretical and Applied Fluid Mechanics , Faculty of Physics, University of Science and Technology Houari Boumediene - USTHB, Algiers, Algeriapaysamataoui@usthb.dzAir entrainment CFD Two phase flow Volume of fluid Air cavity Water plunging jet. [Alireza, J., R. Elahi and M. Passandideh Fard (2013). Numerical Simulation of liquid Sloshing with baffles in the fuel container. The 12th Iranian Aerospace Society Conference. Amir Kabir University of Technology. AERO2013-17469.##
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]Studies on Droplet Size Distribution of Oil-in-Water Emulsion in SMX Static Mixer22Oil droplet size distribution of an emulsion produced by Sulzer Chemtech's static SMX static mixer under flow condition was experimentally studied and reported. The dispersed phase of vegetable oil-in-water (O/W) emulsion produced through static mixer by varying the concentration from 1 to 4 vol % oil in water, flowrate of dispersed and continuous phase and operating time. The effect of run time on oil drop sizes is characterized using the spectra obtained from the particle size analyser. The static mixer with 9 perpendicular elements made of teflon is stacked against each other had a void fraction of 0.93. The sauter mean diameter of oil droplet decreases from 8 µm to 4 µm with an increase in Reynolds number. The emulsion droplets of mean sauter diameter in the range 4.1 µm to 4.7 µm were produced by increasing the concentration of the dispersed phase from 1:100 to 1:25, within a span value of between 30 to 240 sec, at atmospheric pressure and room temperature. Performance equation for sauter mean oil droplet diameter is developed based on the experimental data has ±0.2 rms deviation.107114L.MuruganandamChemical Engineering Department, SCALE, VIT University, Vellore, TN 632014, IndiaChemical Engineering Department, SCALE, VIT University, Vellore, TN 632014, Indiapayslmn@vit.ac.inD.KunalChemical Engineering Department, SCALE, VIT University, Vellore, TN 632014, IndiaChemical Engineering Department, SCALE, VIT University, Vellore, TN 632014, Indiapayskunal.vit101@gmail.comG. O.MelwynChemical Engineering Department, SCALE, VIT University, Vellore, TN 632014, IndiaChemical Engineering Department, SCALE, VIT University, Vellore, TN 632014, Indiapaysmelwingeorge@gmail.comSMX Static mixer Dispersed phase Emulsion Sauter mean oil droplet.[Berkman, P. D. and R. V. Calabrese (1988). Dispersion of viscous liquids by turbulent flow in a static mixer. AIChE Journal 34(4), 602-609.##
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]Numerical Study on the Smoke Flow Characterization and Phenomenon of Plug-Holing under Lateral Smoke Exhaust in Tunnel Fire22Although the lateral smoke extraction system had been adopted in the tunnel and subway, the research on the efficiency of the lateral smoke exhaust system is still lacking. A set of numerical simulations were conducted using Fire Dynamic Simulator (FDS) to analyze the plug-holing phenomenon under lateral smoke extraction system in the tunnel fire. Taking an actual lateral smoke exhaust system in a road tunnel as the prototype, a series of fire cases were simulated, wherein the heat release rate (HRR) of the fire source and mechanical exhaust rate, in particular, varied. The smoke flow characteristic in the lateral exhaust system is analyzed and phenomenon of plug-holing was observed. The temperature and smoke layer near the lateral smoke vent are analyzed, and results show that the phenomenon of plug-holing will decrease the lateral smoke exhaust system performance. The exhausting efficiency would not change significantly as the exhaust rate increasing. The critical Froude number we calculated to determine the phenomenon of plug-holing under lateral smoke exhaust in tunnel fire is 0.48, meanwhile, a saturated Froude number 1.95 was introduced by taking account of a better exhaust efficiency.115126J.YangCollege of Safety and Engineering, Nanjing Tech University, Nanjing, ChinaCollege of Safety and Engineering, Nanjing Tech University, Nanjing, Chinapaysyj931906@njtech.edu.cnX.PanCollege of Safety and Engineering, Nanjing Tech University, Nanjing, ChinaCollege of Safety and Engineering, Nanjing Tech University, Nanjing, Chinapaysxuhaipan@njtech.edu.cnZ.WangInstitute of Fire Science and Engineering, Nanjing Tech University, Nanjing, ChinaInstitute of Fire Science and Engineering, Nanjing Tech University, Nanjing, Chinapayswangzl@njtech.edu.cnM.HuaInstitute of Fire Science and Engineering, Nanjing Tech University, Nanjing, ChinaInstitute of Fire Science and Engineering, Nanjing Tech University, Nanjing, Chinapaysminhua@njtech.edu.cnJ.JiangInstitute of Fire Science and Engineering, Nanjing Tech University, Nanjing, ChinaInstitute of Fire Science and Engineering, Nanjing Tech University, Nanjing, Chinapaysjcjiang@njtech.edu.cnCFD Plug-holing Mechanical smoke exhaust Froude number.[Carvel Ricky. (2015). Review: A review of tunnel fire research from Edinburgh. Fire Safety Journal.##
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]An Innovative Roof Shape in Liquid Storage Tanks to Reduce Dynamic Sloshing Effects22In this study, a new type of tank roof form is suggested to reduce the high impact forces caused by sloshing. Using this roof allows the tank designers to consider less freeboard, which is economically valuable. For this purpose, an experimental investigation has been implemented to evaluate the efficacy of the proposed roof to distribute the contained liquid impact forces in several time stages. In these experimental measurements, a series of shaking table tests are conducted for a partially filled tank under harmonic and various earthquake excitations for both typical and proposed tank roof forms. The liquid impact forces are reasonably evaluated and compared for both types of tank roof. The efficacy of the proposed roof design is validated by experimental results and it is shown that the sloshing loads can significantly be reduced up to an average of 50% for the dimensions considered in the experiments. 127136P.NouraeidaneshInternational Institute of Earthquake Engineering and Seismology (IIEES), Tehran, IranInternational Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iranpaysp.nouraeidanesh@iiees.ac.irM. M.KabiriInternational Institute of Earthquake Engineering and Seismology (IIEES), Tehran, IranInternational Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iranpaysm.kabiri@iiees.ac.irM. A.GoudarziInternational Institute of Earthquake Engineering and SeismologyInternational Institute of Earthquake Engineering and Seismologypaysm.a.goodarzi@iiees.ac.irFreeboard effects Sloshing Rectangular tank Earthquake excitation Shaking table test.[Abramson, H. N., R. L. Bass, O. Faltinsen and H. A. Olsen (1974). Liquid slosh in LNG carriers, 10th Symp. Naval Hydrodynamics, MIT, Cambridge, MA. ##
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]Control of Tip Leakage Flow in Axial Flow Compressor Cascade by Suction on the Blade Tip22One of the important ways of improving axial compressor performance is to control the tip leakage flow near the endwall region. Numerical computations were conducted to investigate the impact of blade tip suction on the axial compressor cascade performance in current paper. Three suction schemes located on the blade tip with different chordwise coverage were investigated in total. The results show that the cascade overall performance can be effectively enhanced by the proper suction scheme on the blade tip and the best scheme should be arranged at slightly downstream of the onset point of the tip leakage vortex (TLV). The control effectiveness and mechanisms are different for the different suction schemes. For the suction scheme covering the starting point of TLV, the onset point of TLV is shifted downstream, while an additional induced leakage flow near the blade leading edge is generated resulting in the increase of mixing loss. It is more effective when the structure of the main TLV is destroyed and divided into different parts by applying the blade tip suction arranged slightly behind the onset point of TLV. In addition, the blade loading is redistributed near the blade tip after the blade tip suction and the total pressure loss caused by the suction slots should also be considered in the design process.137149X.MaoSchool of Power and Energy, Northwestern Polytechnical University，Xi’an, Shaanxi, 710072，P. R. ChinaSchool of Power and Energy, Northwestern Polytechnical University，Xi’an, Shaanxi, 710072，P. R. Chinapaysmaoxiao_chen@163.comB.LiuSchool of Power and Energy, Northwestern Polytechnical University 710072 Xi’an, Shaanxi, P. R. ChinaSchool of Power and Energy, Northwestern Polytechnical University 710072 Xi’an, Shaanxi, P. R. Chinapaysliubo704@nwpu.edu.cnT.TangSchool of Power and Energy, Northwestern Polytechnical University，Xi’an, Shaanxi, 710072，P. R. ChinaSchool of Power and Energy, Northwestern Polytechnical University，Xi’an, Shaanxi, 710072，P. R. Chinapays727873423@qq.comSuction Tip leakage flow Active flow control Axial compressor cascade. [Ashrafi, F., M. Michaud and H. D. Vo (2016). Delay of rotating stall in compressors using plasma actuators. Journal of Turbomachinery 138(9), 091009.##
Beselt, C., M. Eck and D. Peitsch (2014). Three-dimensional flow field in highly loaded compressor cascade. Journal of Turbomachinery 136(10), 101007.##
Bo, X. F. (2011) The experimental and numerical study of the characteristics of compressor cascade boundary layer. Ph. D. thesis, the Northwestern Polytechnical University, xi’an China.##
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Dobrzynski, B., H. Saathoff, G. Kosyna, C. Clemen and V. Gummer (2008). Active flow control in a single-stage axial compressor using tip injection and endwall boundary layer removal. ASME GT2008-50214.##
Du, J., J. Li., L.Gao, F. Lin and J. Chen (2016). The Impact of Casing Groove Location on Stall Margin and Tip Clearance Flow in a Low-Speed Axial Compressor. Journal of Turbomachinery 138(12), 121007.##
Evans, S., H. Hodson, T. Hynes and C. Wakelam (2010). Flow control in a compressor cascade at high incidence. Journal of Propulsion and Power 26(4), 828-836.##
Gbadebo, S. A., N. A. Cumpsty and T. P. Hynes (2008). Control of three-dimensional separations in axial compressors by tailored boundary layer suction. Journal of Turbomachinery 130(1), 011004.##
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Han, S. and J. Zhong (2016). Effect of blade tip winglet on the performance of a highly loaded transonic compressor rotor. Chinese Journal of Aeronautics 29(3), 653-661.##
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]Numerical Investigation of Turbulent Flow around a Recent Horizontal Axis Wind Turbine using Low and High Reynolds Models22The effects of different Reynolds Averaged Navier Stokes (RANS) turbulence models on two near-wall approaches using high and low Reynolds models on predicting performance of horizontal axis wind turbines (HAWTs) were studied for a range of wind conditions where flow over the rotor varied from fully attached to massively separated flow. This paper's main contribution is in establishing which RANS models can produce quantitatively reliable numerical predictions of turbulent flow around wind turbine rotors. The authors used measurements done by the new MEXICO (Model rotor EXperiments In COntrolled conditions) project in the German Dutch wind tunnels (DNW) in order to validate and test CFD (Computational Fluid Dynamic) codes. Four different RANS turbulence models were considered: Spalart-Allmaras; k-ε (RNG); k-ω SST; and the transition γ-Reθ model. At low wind speeds, it was found that all four models were good predictors of aerodynamic performance, and at high wind speeds, where the swirl effect was modeled using wall function corrections in both equations, the k-ε model was considered to be the best model: it was the most accurate within a reasonable computational time.151164A.BouhelalMechanical Engineering and Development Laboratory, École Nationale Polytechnique, B.P. 182, El-Harrach, Alger, 16200, AlgeriaMechanical Engineering and Development Laboratory, École Nationale Polytechnique, B.P. 182, El-Harrach, Alger, 16200, Algeriapaysabdelhamid.bouhelal@g.enp.edu.dzA.SmailiMechanical Engineering and Development Laboratory, École Nationale Polytechnique, B.P. 182, El-Harrach, Alger, 16200, AlgeriaMechanical Engineering and Development Laboratory, École Nationale Polytechnique, B.P. 182, El-Harrach, Alger, 16200, Algeriapaysarezki.smaili@g.enp.edu.dzO.GuerriCentre de Développement des Énergies Renouvelables, B.P. 62, Route de l’Observatoire, Bouzaréah, Alger, AlgeriaCentre de Développement des Énergies Renouvelables, B.P. 62, Route de l’Observatoire, Bouzaréah, Alger, Algeriapayso_guerri@yahoo.comC.MassonDepartment of Mechanical Engineering, École de Technologie Supérieure, 1100 Notre-Dame Ouest, H3C1K3, Montréal, Québec, CanadaDepartment of Mechanical Engineering, École de Technologie Supérieure, 1100 Notre-Dame Ouest, H3C1K3, Montréal, Québec, Canadapayschristian.masson@etsmtl.caAerodynamic analysis HAWT CFD Turbulence modeling RANS low and high Reynolds Models Near-wall treatment New MEXICO measurement.[Abdulqadir, S. A., H. Iacovides and A. Nasser (2016). The physical modelling and aerodynamics of turbulent flows around horizontal axis wind turbines. Energy. ##
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]Detached Eddy Investigation of Conical Cavity Flow at Mach 0.922An improved delayed detached eddy simulation (IDDES) is carried out to investigate both the mean and the instantaneous flow characteristics of conical cavities fixed on a cone surface in a Mach 0.9 freestream. Two model categories, a single cavity model with different length (L) to depth (D) ratio and a multi-cavity model that inserted the separation disk into a single cavity are studied. Results indicate that in case of a single cavity model, the cavity L/D ratio is the key parameter that influences mean flow structure and oscillatory characteristics. The bulk reverse flow structure can be broken up into smaller structures as L/D value reduces from 4.0 to 0.51 inside the cavity. Smaller longitudinal pressure gradients on the cavity wall and the thicker downstream boundary layer are observed when larger L/D values are present. The cavities with smaller L/D values can stimulate the pressure oscillation fundamental frequency as well as the acoustic tones to increase the value. Multi-cavity configurations through insertion of a separation disk into the single cavity are helpful in cutting the large reverse flow structure inside a cavity into a smaller, similar, coherent structure, and to reduce the overall cone drag. The insertion of the separation disk can modulate pressure oscillation peaks and sound pressure levels to higher frequency, however, they are not able to reduce the overall sound pressure inside the cavity. Pressure oscillations within each cavity of the multi-cavity configuration have a weak correlation.165176J.TengSchool of Aerospace Engineering, Xiamen University, Xiamen, Fujian Province, 361005, P. R. ChinaSchool of Aerospace Engineering, Xiamen University, Xiamen, Fujian Province, 361005, P. R. Chinapaystengjian@ymail.comJ.ZhangAECC Hunan Aviation Powerplant Research Institute, Zhuzhou, Hunan Province, 412000, P. R. ChinaAECC Hunan Aviation Powerplant Research Institute, Zhuzhou, Hunan Province, 412000, P. R. Chinapays463143639@qq.comZ.AnAECC Hunan Aviation Powerplant Research Institute, Zhuzhou, Hunan Province, 412000, P. R. ChinaAECC Hunan Aviation Powerplant Research Institute, Zhuzhou, Hunan Province, 412000, P. R. Chinapays616075663@qq.comY.YouSchool of Aerospace Engineering, Xiamen University, Xiamen, Fujian Province, 361005, P. R. ChinaSchool of Aerospace Engineering, Xiamen University, Xiamen, Fujian Province, 361005, P. R. Chinapaysyouyancheng@xmu.edu.cnIDDES Cavity flow Conical Cavity Pressure oscillation Aeroacoustics.[Allmaras, S. R.; F. T. Johnson and P. R. Spalart (2012). Modifications and Clarifications for the Implementation of the Spalart-Allmaras Turbulence Model, Seventh International Conference on Computational Fluid Dynamics (ICCFD7), Big Island, Hawaii, ICCFD7-1902.##
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]Mixed Convection Heat Transfer of Al2O3 Nanofluid on the Elliptical Shapes: Numerical Study of Irreversibility22In this study the 2D laminar and steady water-based Al2O3 nanofluid flow over a cylinder with circular, horizontal and vertical elliptical cross section by constant surface temperature boundary condition has been studied. The main goal of this research is to investigate the effects of different natural and mixed convection heat transfer mechanisms on the convective heat transfer coefficient, and the entropy generation due to the thermal and frictional origination. Conservation equations of the mass, momentum and energy under the assumption of incompressible, Newtonian nanofluid, by using the homogeneous single phase method have been solved. The impact of considered parameters in this study (alteration in cross section, convective flow direction and volume fraction of nano particles) in enhancing the heat transfer rate is studied in association with the entropy generated value in each case. Based on the results, the vertical elliptical cross section, in comparison with others, shows the highest entropy generation value and the heat transfer coefficient in all considered mechanisms. Moreover, mixed convection heat transfer type 2, in which the force flow is perpendicular to the buoyant flow direction, has the highest entropy generation and heat transfer rate for all cross sections. In addition, in all cases in the presence of the nanoparticles, the heat transfer rate and entropy generation increases.177189K.KhajehFaculty of Mechanical Engineering, University of Tabriz, Tabriz, IranFaculty of Mechanical Engineering, University of Tabriz, Tabriz, Iranpaysk.khajeh.2005@tabrizu.ac.irL.JahanshalooFaculty of Mechanical Engineering, University of Tabriz, Tabriz, IranFaculty of Mechanical Engineering, University of Tabriz, Tabriz, Iranpaysleilajahanshaloo@gmail.comS.EbrahimiFaculty of Mechanical Engineering, University of Tabriz, Tabriz, IranFaculty of Mechanical Engineering, University of Tabriz, Tabriz, Iranpaysshahinebrahimi937@yahoo.comH.AminfarFaculty of Mechanical Engineering, University of Tabriz, Tabriz, IranFaculty of Mechanical Engineering, University of Tabriz, Tabriz, Iranpayshh_aminfar@tabrizu.ac.irMixed convection Nanofluid Homogeneous single phase Elliptic cylinder Entropy generation.[Abouali, O. and G. Ahmadi (2012). Computer simulations of natural convection of single phase nanofluids in simple enclosures: a critical review. Applied Thermal Engineering 36, 1-13.##
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]Characterization of Vortex Development and Thermo-Solutal Transfers on Confined Wall Jets Submitted to Suction or Blowing: Part 222A computational study is conducted to explore the effect of vertical wall suction or blowing on two-dimensional confined wall jet hydrodynamic characteristics. Using an implicit finite volume technique in Cartesian coordinate system, several parameters have been investigated for a wide range of Lewis numbers by fixing the Prandtl number at 7 that corresponds to water. The main purpose is to analyze the control size and location effectiveness on the flow pattern as well as heat and mass transfer rates. Detailed numerical simulations demonstrated that as the local blowing is moved downstream, discrete vortex formation begins at a critical location then shedding phenomenon occurs behind the slot at advanced positions. Since the flow dynamic structure is mainly altered, averages skin friction and thermo-solutal coefficients distributions are largely influenced. Approximately for x_s≤4 (upstream of the natural vortex emission position), Nusselt and Sherwood numbers slightly increase with the control location x_s. However, they gradually decrease as the blowing slot approaches the domain exit. Optimum values were obtained when locating the slot just downstream of the uncontrolled Kelvin-Helmholtz instability onset. Furthermore, computations illustrated that an appropriate suction slot length selection could be a simple and efficient tool to delay or even suppress natural structure emission and development. This choice is essentially related to the recirculation cell size. 191204S.MejriLMF : Laboratoire de Mécanique des Fluides-Département de Physique, Faculté des Sciences de Tunis,LMF : Laboratoire de Mécanique des Fluides-Département de Physique, Faculté des Sciences de Tunis,paysmejrisa3ida@gmail.comM. A.KnaniInstitut Préparatoire aux Etudes d’Ingénieurs de Tunis., Université de Tunis, 2 rue Nehru, 1080 Montfleury,Tunisie.Institut Préparatoire aux Etudes d’Ingénieurs de Tunis., Université de Tunis, 2 rue Nehru, 1080 Montfleury,Tunisie.paysmohamedali.knani@ipeit.rnu.tnConfined wall jet Flow control Blowing slot position Suction slot length Lewis number.[Abdulla, N. N. and S. L. G. Jassim (2010). Parametric study of suction or blowing effects on turbulent flow over a flat plate. Journal of Engineering 16(4), 6164-6185.##
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Zhao, F. Y., D. Liu and G. F. Tang (2007). Free convection from one thermal and solute source in a confined porous medium. Transp Porous Med 70, 407-425.##]Swirl Characteristics of Vortex Valve Variable-Thrust Solid Rocket Motor22In accordance with the flow characteristics of vortex valve variable-thrust solid rocket motors, a cold flow experimental system based on Particle Image Velocimetry was established. A flow velocity vector diagram of vortex chamber was generated, and the vortex structure was analyzed. The results provided an experimental foundation for numerical simulation. The flow characteristics in vortex chamber and in the throat and divergent sections of the nozzle were modeled and simulated. The flow in the vortex chamber conformed to the complex Rankine vortex, and the flow field was divided into three different zones. The vortex core was the primary influence factor for thrust modulation. The resultant velocity reached Mach number 1 before gas arrived at nozzle throat, and the axial velocity still reached Mach number 1 at nozzle throat. Hence, the axial velocity can be used to judge the occurrence of choking at the nozzle throat. The intensity of swirl flow in divergent section of the nozzle was evidently lower than that in vortex chamber and throat. As a result, a low-pressure zone emerged around the central axis, thereby causing thrust losses.205215X. G.WeiScience and Technology on Combustion, Internal Flow and Thermal-structure Laboratory， Northwestern Polytechnical University, Xi’an, 710072, P.R. ChinaScience and Technology on Combustion, Internal Flow and Thermal-structure Laboratory， Northwestern Polytechnical University, Xi’an, 710072, P.R. Chinapaysrealysnow@gmail.comJ.LiScience and Technology on Combustion, Internal Flow and Thermal-structure Laboratory， Northwestern Polytechnical University, Xi’an, 710072, P.R. ChinaScience and Technology on Combustion, Internal Flow and Thermal-structure Laboratory， Northwestern Polytechnical University, Xi’an, 710072, P.R. Chinapayslijiang@nwpu.edu.cnG. Q.HeScience and Technology on Combustion, Internal Flow and Thermal-structure Laboratory， Northwestern Polytechnical University, Xi’an, 710072, P.R. ChinaScience and Technology on Combustion, Internal Flow and Thermal-structure Laboratory， Northwestern Polytechnical University, Xi’an, 710072, P.R. Chinapaysgqhe@nwpu.edu.cnSolid propellant rocket motor Thrust modulation Vortex valve Vortex core Particle image velocimetry Flow analysis.[Akhmetov, D. G. and T. D. Akhmetov (2016). Flow structure in a vortex chamber. Journal of Applied Mechanics and Technical Physics 57(5), 879-887.##
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Blatter, A. and T. W. Keranen (1970). A vortex valve for flow modulation of 5500°F gas. Journal of Spacecraft and Rockets 7(2), 169-174.##
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Xianggeng, W., L. I. Jiang and H. E. Guoqiang (2017). Influence of structural parameters on the performance of vortex valve variable-thrust solid rocket motor. International Journal of Turbo and Jet-Engines 34(1), 1-9.##
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]Steady-State Experiment and Simulation of Intake Ports in a Four-Valve Direct Injection Diesel Engine22In order to analyze intake port flow characteristics of a four-valve direct injection (DI) diesel engine, steady-state flow bench experiments and numerical simulations method were coupled to investigate the following four combined intake ports: (1) helical port (left) and tangential port (right); (2) tangential port (left) and helical port (right); (3) helical port (left) port and helical (right); and (4) tangential port (left) and tangential (right) port. Results show that the simulation of port flow coefficients matches experimental findings very well, and the port coefficients of the above four combinations do not vary much, but their swirl ratios are very different. Specifically, when the valve lift is the maximum, the swirl ratio of the combination of "helical and tangential" is the greatest among the four combinations, and the swirl ratio of "tangential and tangential" is the minimum. And the3D fluid simulation method and steady-state experiment are important means to investigate the flow characteristics of the combined intake ports. 217224D. W.JiaYunnan Key Laboratory of Internal Combustion Engine, Kunming University of Science and Technology, Kunming 650500, ChinaYunnan Key Laboratory of Internal Combustion Engine, Kunming University of Science and Technology, Kunming 650500, Chinapays27546658@qq.comX. W.DengYunnan Key Laboratory of Internal Combustion Engine, Kunming University of Science and Technology, Kunming 650500, ChinaYunnan Key Laboratory of Internal Combustion Engine, Kunming University of Science and Technology, Kunming 650500, Chinapays664556969@qq.comJ. L.LeiYunnan Key Laboratory of Internal Combustion Engine, Kunming University of Science and Technology, Kunming 650500, ChinaYunnan Key Laboratory of Internal Combustion Engine, Kunming University of Science and Technology, Kunming 650500, Chinapays22972489@qq.comFour-valve DI diesel engine Flow characteristics Combined intake ports Steady-state experiment Simulation.[Andreatta, É., F. Barbieri, L. Squaiella and R. Sassake (2008). Intake Ports Development: Euro Ⅳ Diesel Engine Cylinder Head. SAE Paper 36-0331.##
Cantore, G., S, Fontanesi and V. Gagliardi (2005). Effects of relative port orientation on the in-cylinder flow patterns in a small unit displacement HSDI Diesel Engine. SAE Paper 32-0093.##
Changming, H., B. Yuhua, L. Jilin and S. Lizhong (2009). A New Design Method for diesel Helical Intake Port Parameter.Transaction of CSICE 27(3) 265-269.##
Choi, M., J. Song and S. Park (2016). Modeling of the fuel injection and combustion process in a CNG direct injection engine. Fuel 179, 168-178.##
Cui, L., T. Wang, Z. Lu, M. Jia and Y. Sun (2015). Full-Parameter Approach for the Intake Port Design of a Four-Valve Direct-Injection Gasoline Engine. Journal of Engineering for Gas Turbines and Power137(9), 091502-091502-11.##
Kawaguchi, A., T. Aiba, N. Takada and K. Ona (2009). A Robustness-Focused Shape Optimization Method for Intake Ports. SAE Technical Paper 2009-01-1777.##
Kawashima, J., H. Ogawa and Y. Tsuru (1998). Research on a Variable Swirl Intake Port for 4-Valve High-Speed DI Diesel Engines. SAE Paper 982680.##
Lu, Z., T. Wang, S. Liu, Z. Lin and Y. Han (2014). Experimental and Modeling Study of the Effect of Manufacturing Deviations on the Flow Characteristics of Tangential Intake Port in a Diesel Engine. Journal of Engineering for Gas Turbines and Power 136(11), 112101-112101-9.##
Rathnaraj, J. D., B. J. Bose and P. M. Kumar (2006). Simulation and experimental investigation of variable swirl intake port in DI Diesel Engine using CFD. European Fluids Engineering Summer Meeting.##
Sun, P., X. Kaiyan, X. Xuefeng and Z. Yanjing (2007). Numerical simulation and experiment on study flow test bench of diesel intake port. Transactions of the Chinese society of agriculture engineering 23(1), 99-104.##
Torre, D., A. G. Montenegro and A. Onorati (2017). Coupled 1D-quasi3D fluid dynamic models for the simulation of IC engine intake and exhaust systems. In 17. Internationales Stuttgarter Symposium (1461-1476). Springer Vieweg, Wiesbaden.##
Yufeng, L. and W. Zhong(2004). Experimental Study of Formation of Intake Swirl in the Cylinder of A 4-Valve Diesel Engine. ACTA Armamentarii 25(1), 113-115.##
Yufeng, L., G. Xiaohui, W. Hai, L. Shuliang and X. Sidu (2001). Effects of Combination and orientation of Intake Ports on Swirl in Four-Valve DI Diesel Engines. Transaction of CSICE 19(3), 209-214.##
Zhuang, H., and Hung, D. L. (2016). Characterization of the effect of intake air swirl motion on time-resolved in-cylinder flow field using quadruple proper orthogonal decomposition. Energy Conversion and Management, 108, 366-376.##
]Experimental Study of Subcooled Boiling Heat Transfer of Axial and Swirling Flows inside Mini Annular Gaps22An experimental study of the subcooled boiling heat transfer of axial and swirling upward flows inside vertical mini annular gaps was conducted using deionized water. The subcooled boiling heat transfer coefficients and the boiling curves of the flow inside mini annular gaps with different gap sizes have been investigated. The experimental results both for the single phase heat transfer and subcooled boiling heat transfer inside mini annular gaps showed very good agreement with correlations in the literature. The results showed that the subcooled boiling heat transfer coefficient for a given heat flux increases as the size of the annular gap is decreased. The maximum wall superheat is also influenced negligibly by mass flux. Furthermore, the effects of swirl flow by using spring insets inside the mini annuli on the single phase and subcooled boiling heat transfer have been studied. The results showed that the single phase and subcooled boiling heat transfer coefficients are increased by having swirl flow inside mini annuli using spring inserts. The obtained results also showed that the heat transfer enhancement by having swirl flow inside the annuli using spring inserts decreases as the applied heat flux is increased in the subcooled boiling heat transfer region.225232S.Ahangar ZonouziDepartment of Mechanical Engineering, Razi University, Kermanshah, Iran.Department of Mechanical Engineering, Razi University, Kermanshah, Iran.payssajjadahangar@gmail.comH.SafarzadehDepartment of Mechanical Engineering, Razi University, Kermanshah, Iran.Department of Mechanical Engineering, Razi University, Kermanshah, Iran.payshsafarzadeh@razi.ac.irH.AminfarFaculty of Mechanical Engineering, University of Tabriz, Tabriz, IranFaculty of Mechanical Engineering, University of Tabriz, Tabriz, Iranpayshh_aminfar@tabrizu.ac.irM.MohammadpourfardFaculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, Iran.Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, Iran.paysmohammadpour@tabrizu.ac.irFlow Boiling Mini Annular Gap Swirling Flow Subcooled Heat Transfer. [Akhavan Behabadi, M. A., R. Kumar and M. Jamali (2009). Investigation on heat transfer and pressure drop during swirl flow boiling of R-134a in horizontal tube. Int. J. Heat Mass Transfer 52, 1918-1927.##
Cikim, T., E. Armagan, G. O. Ince and A. Kosar (2014). Flow boiling enhancement in microtubes with crosslinked pHEMA coatings and the effect of coating thickness, J. Heat Transfer-Trans. ASME 136, 081504-081504-11.##
El-Genk, M. S. and D. V. Rao (2007). Heat transfer experiments and correlations for low Reynolds number flows of water in vertical annuli, Heat Transfer Engineering 10(2), 44-57.##
Hata, K. and S. Masuzaki (2011a). Heat transfer and critical heat flux of subcooled water flow boiling in a SUS304-tube with twisted-tape insert, J. Therm. Sci. Eng. Appl. 3, 012001-012001-12##
Hata, K. and S. Masuzaki (2011b). Twisted-tape-induced swirl flow heat transfer and pressure drop in a short circular tube under velocities controlled, Nucl. Eng. Des. 241, 4434–4444.##
Kandlikar, S. G. (2012). History, advances, and challenges in liquid flow and flow boiling heat transfer in microchannels: a critical review, J. Heat Transf 134 (3), 34001.##
Salim, M. M. and D. M. France (2005). Post-CHF axial and swirl flow heat transfer in small horizontal tubes, Journal of thermophysics and heat transfer 19, 163-171.##
Shah, M. M. (2017). New correlation for heat transfer during subcooled boiling in plain channels and annuli, International Journal of Thermal Sciences 112, 358-370.##
Yagov, V. V. (2005) Heat transfer and crisis in swirl flow boiling, Exp. Therm. Fluid Sci 29, 871–883.##
]CFD Study on Jet Stirred Oxidation Pond of Absorption Tower in Power Plant22In the paper, the standard k-ε model and the SST k-ω model were employed to predict the velocity field in the jet mixing tank, and the simulation results were validated by experimental data. It showed that the standard k-ε model can predict the velocity field of jet mixing tank more accurately than the SST k-ω model. The standard k-ε model was applied to investigate the effects of the jet inclination angle (i.e., 0°, 10°, 20°, 30° and 40°) and the jet velocity (i.e., 14, 16, 18 and 20m/s) on the mixing uniformity of the jet mixing oxidation pond. Based on the evaluation criterions: un-precipitated area ratio (UPAR) and non-uniform velocity coefficient (NUVC) proposed in the paper, when the jet inclination angle and jet velocity are 10° and 18m/s, respectively, the jet mixing effect in the oxidation pond is the best. The study can be helpful for the optimization of the flow field in the jet mixing oxidation pond to improve the desulfurization efficiency.233240W.LiInstitute of Refrigeration and Cryogenics Engineering, Shanghai Jiao Tong University, Shanghai 200240, ChinaInstitute of Refrigeration and Cryogenics Engineering, Shanghai Jiao Tong University, Shanghai 200240, Chinapaysweili162@foxmail.comY.YaoInstitute of Refrigeration and Cryogenics Engineering, Shanghai Jiao Tong University, Shanghai 200240, ChinaInstitute of Refrigeration and Cryogenics Engineering, Shanghai Jiao Tong University, Shanghai 200240, Chinapaysyeyao10000@sjtu.edu.cnJ.ChenNanjing Vocational Institute of Transport Technology, Nanjing 211188, Jiangsu Province, ChinaNanjing Vocational Institute of Transport Technology, Nanjing 211188, Jiangsu Province, Chinapayschenjing7618@163.comJet mixing Fluent Inclination angle Jet velocity Optimization Oxidation pond. [Coldrey, P. (1978). paper to IChemE Course. University of Bradford, England.##
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]On the Instability of Two Dimensional Backward-Facing Step Flow using Energy Gradient Method22In the present paper, the energy gradient method is implemented to study the instability of 2-D laminar backward-facing step (BFS) flow under different Reynolds numbers and expansion ratios. For this purpose, six different Reynolds numbers (50 ≤ Re ≤ 1000) and two various expansion ratios of 1.9423 and 3 are considered. We compared our results of the present study with existing experimental and numerical data and good agreement is achieved. To study of fluid flow instability, we evaluated the distributions of velocity, vorticity and energy gradient function K. The results of our study show that as the expansion ratio decreases the flow becomes more stable. We also found that the origin of instability in the entire flow field is located on the separated shear layer nearby the step edge. In addition, we approved that the inflection point on the profile of velocity corresponds to the maximum of vorticity resulted to the instability.241256H.NowruziDepartment of Maritime Engineering, Amirkabir University of Technology, Tehran, Tehran, IranDepartment of Maritime Engineering, Amirkabir University of Technology, Tehran, Tehran, Iranpaysh.nowruzi@aut.ac.irS.Salman NourazarDepartment of Mechanical Engineering, Amirkabir University of Technology, Tehran, IranDepartment of Mechanical Engineering, Amirkabir University of Technology, Tehran, Iranpaysicp@aut.ac.irH.GhassemiDepartment of Maritime Engineering, Amirkabir University of Technology, Tehran, Tehran, IranDepartment of Maritime Engineering, Amirkabir University of Technology, Tehran, Tehran, Iranpaysgasemi@aut.ac.irEnergy gradient Instability Backward-facing step flow.[Armaly, B. F., F. Durst, J. C. F. Peireira and B. Schönung (1983). Experimental and theoretical investigation of backward-facing step flow. Journal of Fluid Mechanics 127, 473–496.##
Asgari, E. and M. Tadjfar (2017). Assessment of four inflow conditions on large-eddy simulation of a gently curved backward-facing step. Journal of Turbulence 18, 61–86. ##
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Blackburn, H. M., D. Barkley and S. J. Sherwin (2008). Convective instability and transient growth in flow over a backward-facing step. Journal of Fluid Mechanics 603, 271–304.##
Bolgar, I., S. Scharnowski and C. J. Kähler (2015). Control of the reattachment length of a transonic 2D backward-facing step flow. In Proceedings of the 5th International Conference on Jets, Wakes and Separated Flows, Stockholm, Sweden.##
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de la Torre, M., A. Acosta-Zamora, N. D. Love and A.R. Choudhuri (2017). Study of high intensity turbulent flow over a backward facing step using 10kHz particle image velocimetry. In Proceedings of the 55th AIAA Aerospace Sciences Meeting, Texas, USA. ##
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]Optimization and Biodiesel Production from Prosopis Julifera Oil with High Free Fatty Acids22Prosopis julifera is a non-edible feedstock found in the arid and semi-arid regions was used for the production of biodiesel. Solvent extraction technique was used for oil extraction from Prosopis julifera .The present work mainly concentrates on the three step process of biodiesel production from Prosopis julifera oil .The acid value of Prosopis julifera oil was reduced below 1% using acid catalyst 1% v/v H2SO4 followed by esterification process using alkaline catalyst (KOH).Transesterification reaction is found to be affected by the reaction variables namely methanol to oil molar ratio, amount of catalyst used, reaction time and reaction temperature. Gas chromatography was used to analyse the Fatty acid methyl esters. The methyl ester obtained from the previous step was refined to produce biodiesel. The fuel properties of Prosopis julifera methyl ester (PJME) such as viscosity, cetane number, flash point, acid value, etc were determined and compared according to the ASTM standards. The optimum reaction conditions of Methanol/oil molar ratio of 9:1v/v, reaction temperature of 550C, reaction time of 2 hrs and 0.75% w/v of KOH usage were determined. Response surface Methodology (RSM) technique was used to optimize the maximum yield of Prosopis julifera methyl ester. 257270M.RajeshwaranDepartment of Mechanical Engineering, Mohamed Sathak Engineering College, Ramanathapuram – 623 806, Tamil Nadu, IndiaDepartment of Mechanical Engineering, Mohamed Sathak Engineering College, Ramanathapuram – 623 806, Tamil Nadu, Indiapaysrajeshwaran.phd@gmail.comP.GaneshanDepartment of Mechanical Engineering, VSB Engineering College, Karur - 639 111, Tamil Nadu, IndiaDepartment of Mechanical Engineering, VSB Engineering College, Karur - 639 111, Tamil Nadu, Indiapaysganeshram84@gmail.comK.RajaDepartment of Mechanical Engineering, Anna University, University college of Engineering, Dindigul - 624005, Tamil Nadu, IndiaDepartment of Mechanical Engineering, Anna University, University college of Engineering, Dindigul - 624005, Tamil Nadu, Indiapaysrajagce@gmail.comProsopis julifera Acid Esterification Transesterification Process optimization.[Atabani, A. E. (2013). Non-edible Vegetable Oils: A Critical Evolution of Oil Extraction, Fatty Acid Compositions, Biodiesel Production, Characteristics, Engine Performance and Emission Production. Renewable and Sustainable Energy Reviews 18, 211-245.##
Balat, M. (2011). Potential alternatives to edible oils for biodiesel production – A review of current work. Energy Conversion and Management 52; 1479–1492.##
Barbosa, D. C., T. M. Serra, S. M. P. Meneghetti and M. R. Meneghetti (2010). Biodiesel production by ethanolysis of mixed castor and soybean oils. Fuel 89, 3791–4.##
Ghadge, S. V. and H. Raheman (2005). Biodiesel production from mahua (Madhuca indica) oil having high free fatty acids, Biomass and Bioenergy 28, 601–605##
Ivana, B., Bankovi´,Olivera S. Stamenkovi´,Vlada B. Veljkovi´(2012), Biodiesel production from non-edible plant oils, Renewable and Sustainable Energy Reviews 16, 3621– 3647.##
Jennifer, B. (2013). Is there such a Thing as Wasteland Biofuels and Wasteland Development in Tamil Nadu, India.##
Lin, L., D. Ying, S. Chaitep and S. Vittayapaung (2009). Biodiesel production from crude rice bran oil and properties as fuel, Applied energy 86, 681-688.##
Mambully, C. G. (2009). Biofuels: Opportunities and Challenges in India, Springer-In vitro cell.Dev.Biol-plant 45, 350-371.##
Melvin Jose, D. F., R. Edwin Raj, B. Durga Prasad, Z. Robert Kennedy and A. M. Ibrahim (2011). A multi-variant approach to optimize process parameters for biodiesel extraction from rubber seed oil, Applied Energy 88, 2056–2063.##
Milan D. Kosti, Natasa M. Jokovi, Olivera S. Stamenkovi, Katarina M. Rajkovic, Petar S. Milic, Vlada and B. Veljkovic (2014). Optimization of Hempseed Oil Extraction by n-hexane., Industry Crops and Products 52, 679-686.##
Palash, S. M., M. A. Kalam, H. H. Masjuki, B. M. Masum, I. M. Rizwanul Fattah and M. Mofijur (2013). Impacts of biodiesel combustion on Nox emissions and their reduction approaches, Renewable and Sustainable Energy Reviews. 23, 473-490. ##
Pragnesh, N. Dave (2013) International Journal of Chemical Studies, Prosopis julifera: A review 2321-4902.##
Rajeshwaran, M. K. Raja, P. Marimuthu, M. D. Duraimurugan alias Saravanan (2016). Biodiesel Production and Optimization from Prosopis Julifera oil – A Three step method” Int J Adv Engg Tech/Vol. VII/Issue II/April-June,214-224.##
Ramadhas, A. S., S. Jayaraj and C. Muraleedharan (2005). Biodiesel production from high FFA rubber seed oil, Fuel 84, 335–340.##
Atapour, M. and H. R. Kariminia (2011). Characterization and transesterification of Iranian bitter almond oil for biodiesel production, Applied Energy 88, 2377–2381.##
]Natural Convection in an Enclosure with a Discretely Heated Sidewall: Heatlines and Flow Visualization22Natural convection inside a rectangular enclosure is investigated experimentally and numerically. One of the sidewalls is heated discretely by two flush-mounted heat sources. The other sidewall is kept at a constant temperature, while the horizontal walls are unheated. Heat dissipation rates of the heat sources are equal to each other. The aspect ratio of the enclosure (AR) is 2 and the working fluid is air (Pr=0.71). The study is focused on the validation of the two and three dimensional computations under real test conditions against experiments for various modified Rayleigh number values. Experimental study is performed for various modified Rayleigh numbers in the range of 7.7x105 and 3.1x106 while numerical part covers the values between 104 and 5x106. Temperature measurements and flow visualization studies are performed in the experimental work, and streamlines, isotherms and heatlines are presented in the numerical part of the study. From the experimental and numerical studies, it is shown that two dimensional computations reflects the general characteristics of the problem, conduction and radiation heat transfer are not negligible, surface temperatures increase with the modified Rayleigh number and heatline approach is an important tool to analyze convective heat transfer. 271284M.SaglamKaradeniz Technical University Department of Mechanical Engineering, 61080 Trabzon, TurkeyKaradeniz Technical University Department of Mechanical Engineering, 61080 Trabzon, Turkeypaysmehmetsaglam@ktu.edu.trB.SarperGumushane University Department of Mechanical Engineering, 29100 Gumushane, TurkeyGumushane University Department of Mechanical Engineering, 29100 Gumushane, Turkeypaysbugrasarper@gumushane.edu.trO.AydinKaradeniz Technical University Department of Mechanical Engineering, 61080 Trabzon, TurkeyKaradeniz Technical University Department of Mechanical Engineering, 61080 Trabzon, Turkeypaysoaydin@ktu.edu.trNatural convection Electronics cooling Rectangular enclosure Discrete heating Surface radiation Conjugate Flow visualization Heatlines.[ANSYS Inc. (2013), ANSYS Fluent User’s Guide Release 15.##
Aydin, O. and I. Pop (2005). Natural convection from a discrete heater in enclosures filled with a micropolar fluid. International journal of engineering science 43(19), 1409-1418.##
Aydin, O. and W. J. Yang (2000). Natural convection in enclosures with localized heating from below and symmetrical cooling from sides. International Journal of Numerical Methods for Heat and Fluid Flow 10(5), 518-529. ##
Aydin, O. and W. J. Yang (2000). Mixed convection in cavities with a locally heated lower wall and moving sidewalls. Numerical Heat Transfer: Part A: Applications 37(7), 695-710. ##
Baïri, A. (2008). Transient thermal characteristics of airborne electronic equipment with discrete hot bands in square cavities. Applied Energy 85(10), 951-967.##
Baïri, A., J. G. de María, N. Laraqi and N. Alilat (2008). Free convection generated in an enclosure by alternate heated bands. Experimental and numerical study adapted to electronics thermal control. International Journal of Heat and Fluid Flow 29(5), 1337-1346. ##
Calcagni, B., F. Marsili and M. Paroncini (2005). Natural convective heat transfer in square enclosures heated from below. Applied Thermal Engineering 25(16), 2522-2531. ##
Chadwick, M., B. Webb and H. Heaton (1991). Natural convection from two-dimensional discrete heat sources in a rectangular enclosure. International Journal of Heat and Mass Transfer 34(7), 1679-1693.##
Corcione, M. and E. Habib (2010). Buoyant heat transport in fluids across tilted square cavities discretely heated at one side. International Journal of Thermal Sciences 49, 797-808.##
Corvaro, F. and M. Paroncini (2007). Experimental analysis of natural convection in square cavities heated from below with 2D-PIV and holographic interferometry techniques. Experimental Thermal and Fluid Science 31(7), 721-739.##
Da Silva, A. K., S. Lorente and A. Bejan (2004). Optimal distribution of discrete heat sources on a wall with natural convection. International Journal of Heat and Mass Transfer 47, 203-214.##
Deng, Q. H. (2008). Fluid flow and heat transfer characteristics of natural convection in square cavities due to discrete source–sink pairs. International Journal of Heat and Mass Transfer 51(25), 5949-5957.##
Deng, Q. H. and G. F. Tang (2002). Numerical visualization of mass and heat transport for conjugate natural convection/heat conduction by streamline and heatline. International Journal of Heat and Mass Transfer 45(11), 2373-2385.##
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Flack, R. and B. Turner (1980). Heat Transfer Correlations for Use in Naturally Cooled Enclosures with High-Power Integrated Circuits. IEEE Transactions on Components, Hybrids, and Manufacturing Technology 3(3), 449-452. ##
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Mahapatra, P. S., S. Chatterjee, A. Mukhopadhyay, N. K. Manna and K. Ghosh (2016). Proper orthogonal decomposition of thermally-induced flow structure in an enclosure with alternately active localized heat sources. International Journal of Heat and Mass Transfer 94, 373-379.##
Mahapatra, P. S., N. K. Manna and K. Ghosh (2015). Effect of active wall location in a partially heated enclosure. International Communications in Heat and Mass Transfer 61, 69-77. ##
Mahapatra, P. S., N. K. Manna, K. Ghosh and A. Mukhopadhyay (2015). Heat transfer assessment of an alternately active bi-heater undergoing transient natural convection. International Journal of Heat and Mass Transfer 83, 450-464.##
Naffouti, T., J. Zinoubi, N. A. Che Sidik and R. B. Maad (2016). Applied thermal Lattice Boltzmann model for fluid flow of free convection in 2-D enclosure with localized two active blocks: heat transfer optimization. Journal of Applied Fluid Mechanics 9(1), 419-430.##
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Purusothaman, A., V. Divya, N. Nithyadevi and H. F. Oztop (2016). An analysis on free convection cooling of a 3x3 heater array in rectangular enclosure using Cu-EG-water nanofluid. Journal of Applied Fluid Mechanics 9(6), 3147-3157.##
Purusothaman, A., N. Nithyadevi, H. Oztop, V. Divya and K. Al Salem (2016). Three dimensional numerical analysis of natural convection cooling with an array of discrete heaters embedded in nanofluid filled enclosure. Advanced Powder Technology 27(1), 268-280.##
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]Experimental and Computational Analysis on Aerodynamic Behavior of a Car Model with Vortex Generators at Different Yaw Angles22Investigating the effects of aerodynamic characteristics in the automotive segment has been one of the thrust areas of research in the recent years. Extensive research had been carried out earlier in minimizing the aerodynamic drag of the car body and to study the effects using passive air flow deflectors. Little work has been conducted on semi-active or actively controlled air flow modification techniques. In order to contribute new knowledge in the chosen area and to draw the attention of current researchers the present work focuses on the study of aerodynamic characteristics of a typical sedan car model equipped with three numbers of delta shaped vortex generators (VGs) as an aerodynamic add-on device to delay the early flow separation of air from the vehicle body. The yaw angles of the VGs are semi actively controlled using mini stepper motors. The middle VG is kept stationary, whereas the other two VGs orientation has been modified and the results have been studied. The aerodynamic property of a car model mounted with four distinct yaw angle configurations obtained by means of mini stepper motor has been quantitatively evaluated by sub-sonic wind tunnel tests and computational analysis. From the experiments the peak drag and lift coefficient reduction rates of 4.53% and 2.55% respectively have been observed in the case of car model with vortex generators having leading edges facing the rear end and the mid plane of the car respectively when compared with the car model without vortex generators. Numerical simulation using realizable (k- ε) model predicted the drag and lift coefficient reduction rates closer to the experimental values and also it predicted the existence of magnitude of turbulent kinetic energy variation in the roof portion of the car model with four dissimilar configurations of vortex generators relative to the case of car model without vortex generators. 285295G.ShankarDepartment of Automobile Engineering Madras Institute of Technology Campus, Anna University, Chromepet, Chennai, Tamilnadu, India.Department of Automobile Engineering Madras Institute of Technology Campus, Anna University, Chromepet, Chennai, Tamilnadu, India.paysshankarg1990@gmail.comG.DevaradjaneDepartment of Automobile Engineering Madras Institute of Technology Campus, Anna University, Chromepet, Chennai, Tamilnadu, India.Department of Automobile Engineering Madras Institute of Technology Campus, Anna University, Chromepet, Chennai, Tamilnadu, India.paysshankarg1990@yahoo.comDrag force Lift force Vortex generators Wind tunnel Ahmed body Computational simulation Stepper motor.[Aider, J. L., J. F. Beaudoin and J. E. Wesfreid (2010). Drag and lift reduction of a 3D bluff-body using active vortex generators. Experiments in fluids 48(5), 771-789.##
Aljure, D. E., O. Lehmkuhl, I. Rodriguez and A. Oliva (2014). Flow and turbulent structures around simplified car models. Computers and Fluids 96, 122-135.##
Bello Millán, F. J., T. Mäkelä, L. Parras, C. Del Pino and C. Ferrera (2016). Experimental study on Ahmed's body drag coefficient for different yaw angles.## Journal of Wind Engineering and Industrial Aerodynamics 157, 140-144.##
Birwa, S. K., N. Rathi and R. Gupta (2013). Aerodynamic analysis of Audi A4 Sedan using CFD. Journal of The Institution of Engineers (India): Series C, 94(2), 105-111.##
Castro, N., O. D. Lopez and L. Munoz (2013). Computational prediction of a vehicle aerodynamics using detached Eddy simulation. SAE International Journal of Passenger Cars-Mechanical Systems 6(2013-01-1254), 414-423.##
Gillieron, P. and A. Kourta (2013). Aerodynamic drag control by pulsed jets on simplified car geometry. Experiments in fluids 54(2), 1-16.##
Gopal, P. and T. Senthilkumar (2013). Influence of Wake Characteristics of a Representative Car Model by Delaying Boundary Layer Separation. Journal of Applied Science and Engineering 16(4), 363-374.##
Guilmineau, E. (2008). Computational study of flow around a simplified car body. Journal of wind engineering and industrial aerodynamics 96(6), 1207-1217.##
Howell, J. (2015). Aerodynamic Drag of Passenger Cars at Yaw, SAE SAE International of journal of Passenger Cars - Mech. Syst. 8(1), 306-316.##
Howell, J., M. A. Passmore and S. Tuplin (2013). Aerodynamic drag reduction on a simple car-like shape with rear upper body taper. SAE Internation journal for passenger cars-Mech syst 6, 52-60.##
Koike, M., T. Nagayoshi and N. Hamamoto (2004). Research on aerodynamic drag reduction by vortex generators. Mitsubishi motors technical review16, 11-16.##
Koitrand, S., L. Lofdahl, S. Rehnberg and Gaylard, A., (2014). A Computational Investigation of Ground Simulation for a Saloon Car. SAE International Journal of Commercial Vehicles 7(2014-01-0615), 111-123.##
Littlewood, R. P. and M. A. Passmore (2012). Aerodynamic drag reduction of a simplified square back vehicle using steady blowing. Experiments in fluids 53(2), 519-529.##
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