Spatiotemporal Characteristics and Pressure Fluctuations of Internal Flow in a High-Speed Centrifugal Blower for Vacuum Cleaner at Low Flow-Rate Conditions

Document Type : Regular Article

Authors

Key Laboratory of Fluid Transmission Technology of Zhejiang Province, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China.

Abstract

The steady and unsteady characteristics of the internal flow in a high-speed centrifugal blower are studied by computational fluid dynamics (CFD) approach at low flow rates. It is demonstrated that as the flow rate decreases, the separation of flow in the blade passage becomes serious, and separated vortexes always occur on the suction surface of the blade which gradually expand and block the passage. The stall cells move downstream and generate vortices at the exit of the passage, resulting serious loss to the performance of the blower. Q-criteria is used to analyze the flow field and explore the evolution of the vortex structure in the impeller. It is further found that strong pressure fluctuations are caused by the rotating stall in the impeller. At the stall conditions, the instability characteristics are particularly obvious. At flow rates of 0.65Qn and 0.47Qn, the pressure fluctuation in the blade passage is dominated by the blade passing frequency, while a lower frequency dominates at 0.26Qn. Moreover, the flow on the suction surface of impeller blades fluctuates substantially. The characteristics of steady flow and unsteady flow can clearly explain the internal flow of centrifugal blower for vacuum cleaners at low-flow conditions, which can be widely used in various engineering designs of vacuum cleaners.

Keywords


Bai, L. and Z. Song (2020). Simulation analysis of multistage vacuum cleaner fan flow filed. Mechanical Design and Manufacturing 11, 224-227.##
Borello, D., A. Corsini, G. Delibra, M. Fiorito and A. G. Sheard (2013). Large-eddy simulation of a tunnel ventilation fan. Journal of Fluids Engineering 135(7), 071102, 1-9.##
Chun, G., M. Wang and Z. Tang (2011). A Study on surge and stall under the interaction of parallel axial flow fan in tunnel. Noise & Vibration Worldwide 42(11), 9-14.##
Gan, J., F. Liu, M. Liu and K. Wu (2008). The unsteady fluctuating pressure and velocity in a cross flow fan. Journal of Thermal Science 17(04), 349-355.##
Gao, F. and W. Zhong (2012). Numerical simulation and experiment research on pressure fluctuation and aerodynamic noise field of a multi-blade centrifugal fan. Advanced Materials Research 1670, 468-471.##
Ishida, M., T. Surana, H. Ueki and D. Sakaguchi (2005). Suppression of unstable flow at small flow rates in a centrifugal blower by controlling tip leakage flow and reverse flow. Journal od turbomachinery-transactions of the ASME 7(1), 76-83.##
Ming, L., X. Hu, H. Zhang and A. Sun (2018). Optimized design of high-speed centrifugal fan for vacuum cleaner. Fan Technology, 60(S1), 7-13.##
Park, J. W., D. Y. Hwang and H. K. Park (2008). Performance improvement of a vacuum cleaner by analysis of the flow around motor. ASME Fluids Engineering 10-14, 1167-1171.##
Sandra, V. S., B. T. Rafael, S. M. Carlos and G. P. JoseĢ (2005). Unsteady flow pattern characteristics downstream of a forward-curved blades centrifugal fan. Journal of Fluids Engineering 123, 265-70.##
Shen, Y., Y. Li, H. Wang, W. Shen, Y. Chen and H. Si (2019). Numerical simulation and performance optimization of the centrifugal fan in a vacuum cleaner. Modern Physics Letters B 33(35), 1950440, 1-21.##
Sundstrm, E., B. Semlitsch and M. Mihescu (2018). Generation mechanisms of rotating stall and surge in centrifugal compressors. Flow, Turbulence and Combustion 100(3), 705-719.##
Wang, Z., Y. Wei and Y. Qian (2020). A bounce back-immersed boundary-lattice Boltzmann model for curved boundary. Applied Mathematical Modelling 81, 428-440.##
Wei, Y., L. Zhu and Z. Wang (2019). Numerical and experimental investigations on the flow and noise characteristics in a centrifugal fan with step tongue volutes. ARCHIVE Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science 234(15), 2979-2993.##
Wolfram, D. and T. Carolus (2010). Experimental and numerical investigation of the unsteady flow field and tone generation in an isolated centrifugal fan impeller. Journal of Sound & Vibration 329(21), 4380-4397.##
Yang, H., W. Zhang and Z. Zhu (2019). Unsteady mixed convection in a square enclosure with an inner cylinder rotating in a bi-directional and time-periodic mode. International Journal of Heat and Mass Transfer 136, 563-580.##
Yang, J., L. Meng, L. Zhou, Y. Luo and Z. Wang (2013). Unsteady internal flow field simulations in a double suction centrifugal fan. Engineering Computations 30(3), 345-356. ##
Younsi, M., F. Bakir and S. Kouidri (2007). Numerical and experimental study of unsteady flow in centrifugal fan. Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy 221, 1025-36.##
Zhang, W., Y. Lu, W. Gong and G. Xi (2013). The performance impact of half-high diffuser in centrifugal fan for vacuum cleaner. Electrical Equipment S1, 633-637.##
Zhang, J., W. Chu, H. Zhang, Y. Wu and X. Dong (2016). Numerical and experimental investigations of the unsteady aerodynamics and aero-acoustics characteristics of a backward curved blade centrifugal fan. Applied Acoustics 110, 256-267.##
Zhang, L., R. He, X. Wang, Q. Zhang and S. Wang (2019a). Study on static and dynamic characteristics of an axial fan with abnormal blade under rotating stall conditions. Energy 170, 305-325.##
Zhang, W., X. Li and Z. Zhu (2019b). Quantification of wake unsteadiness for low-Re flow across two staggered cylinders. ARCHIVE Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science 233, 19-20.##
Zhang, Y., Q. Chen, Y. Zhang and X. Jia (2011). Numerical simulation and experiment research on aerodynamic characteristics of a multi-blade centrifugal fan. Advanced Materials Research 1380, 317-319.##
Zhou, P., J. Dai, Y. Li, T. Chen and J. Mou (2018). Unsteady flow structures in centrifugal pump under two types of stall conditions. Journal of Hydrodynamics 30(6), 1038-1044.##
Volume 16, Issue 2 - Serial Number 70
February 2023
Pages 375-388
  • Received: 17 April 2022
  • Revised: 04 September 2022
  • Accepted: 30 September 2022
  • Available online: 30 November 2022