Geometric Effects on Suction Recirculation, Cavitation, and Flow Instability of a Centrifugal Pump
A centrifugal pump may experience severe degradation and failure when operating under off-design conditions. In such cases, three representative abnormal flow phenomena may occur: suction recirculation, cavitation, and flow instability. Suction recirculation is a phenomenon where reverse flow and strong swirling flow develop upstream of the impeller under part-load conditions. Cavitation occurs when the liquid pressure drops below the saturation pressure, causing vaporization. Flow patterns become highly complex due to incidence or diffusion when the pump operates at part-load, ultimately leading to flow instability characterized by time-dependent unsteady behavior. In this study, parametric analyses of the impeller and volute geometries were conducted to control these flow phenomena. Additionally, surrogate-based optimization techniques were applied to establish a methodology for optimal pump design.
Shim, H. S., and Kim, K. Y.*, 2022, “Effects of the number of blades on impeller-volute interaction and flow instability of a centrifugal pump,” Proc. Inst. Mech. Eng. Part A J. Power Energy, Vol. 236, No. 8., pp. 1500-1517.
Shim, H. S., and Kim, K. Y.*, 2020, “Relationship between Flow Instability and Performance of a Centrifugal Pump with a Volute,” ASME J. Fluids Eng., Vol. 142, No. 11, 111208 (13 pages).
Shim, H. S., and Kim, K. Y.*, 2020, “Design Optimization of the Impeller and Volute of a Centrifugal Pump to Improve the Hydraulic Performance and Flow Stability,” ASME J. Fluids Eng., Vol. 142, No. 10, 101211 (16 pages).
Shim, H. S., and Kim, K. Y.*, 2020, “Effects of the Cross-sectional Area of a Volute on Suction Recirculation and Cavitation in a Centrifugal Pump,” ASME J. Fluids Eng., Vol. 142, No. 5, 051204 (14 pages).
Shim, H. S., and Kim, K. Y.*, 2019, “Evaluation of Rotor-Stator Interface Models for the Prediction of the Hydraulic and Suction Performance of a Centrifugal Pump,” ASME J. Fluids Eng., Vol. 141, No. 11, 111106 (13 pages).
Shim, H. S., Kim, K.Y.* and Choi, Y. S., 2018, “Three-Objective Optimization of a Centrifugal Pump to Reduce Flow Recirculation and Cavitation,” ASME J. Fluids Eng., Vol. 140, No. 9, 091202 (14 pages).
Rotor-Stator (IGV-Rotor-Diffuser) Interaction of an Axial-Flow Pump
A submersible axial-flow pump consists of inlet guide vanes, rotor blades, and diffuser vanes to achieve optimal hydrodynamic performance. Their relative motions may induce rotor-stator interaction (RSI). RSI occurs when a rotor (or stator) blade passes through the wake of an upstream stator (or rotor) blade, resulting in fluctuations in the flow pattern and fluid forces. The wakes from upstream blades can cause significant vibration issues for downstream blades, particularly at the blade passing frequency or its multiples. This study numerically investigated the effects of the discharge angle of inlet guide vanes and the pitch angle of rotor blades on the hydrodynamic performance of a submersible axial-flow pump. Unsteady flow characteristics were also examined under off-design conditions, considering the mutual effects of geometric parameters on RSI.
Kim, Y. S., Shim, H. S., and Kim, K. Y.*, 2020, “Comparison of Effects of IGV and Blade Pitch Angles on the Performance of a Submersible Axial-Flow Pump,” Proc. Inst. Mech. Eng. Part A J. Power Energy, Vol. 235, No. 4, pp. 718-732.
Kim, Y. S., Heo, M. W., Shim, H. S., Kim, S.H. and Kim, K. Y.*, 2020, “Hydrodynamic Optimization for Design of a Submersible Axial-Flow Pump with a Swept Impeller,” Energies, Vol. 13, No. 12, 3053 (18 pages).
Kim, Y. S. Shim, H. S. and Kim, K. Y., 2019, " Investigation of Unsteady Performance Characteristics of A Submersible Axial-Flow Pump for Different IGV and Blade Pitch Angles," in Proceedings of the ASME-JSME-KSME Joint Fluids Engineering Conference 2019 (AJK Fluids 2019), San Francisco, CA, USA, July 28-August 1, AJKFLUID2019-4860.
Kim, Y. S. Shim, H. S. and Kim, K. Y., 2018, "Interactional Effects of Inlet Guide Vane and Blade Angle on Hydraulic Performance Characteristics of A Submersible Axial-Flow Pump," in Proceedings of the 5th Joint US-European Fluids Engineering Summer Conference (ASME FEDSM 2018), Montreal, Quebec, Canada, July 2018, FEDSM 2018-83126.