Abstract：Numerical simulation was applied to analyze effects of cavitating flow on pressure fluctution near the cutwaters in a double-volute centrifugal pump to investigate the mechansems for pump vibration and noise induced by the flow.The SST k-ω turbulence model and Zwart-Gerber-Belamri cavitation model were selected to carry out unsteady simulations of non-cavitating flow and cavitating flow in the pump under design condition. The numerical results show that the SST k-ω turbulence mo-del can accurately predict the pump perfromance. Vapour bubbles occur initlally on the blade suction side near the blade leading edge and impeller hub.With the decrease of NPSHA(net positive suction head available), the vapour bubbles develop along the blade suction side towards the blade outlet and impeller shroud.The vapour bubbles uneven development in different flow passages intensifies the unstablility of the flow in the impeller.Comparing the flow patterns ofcavitation and non-cavitation flows in one revolution of the impeller, the pressure fluctuation in every monitoring point near two cutwaters domonstrates an obvious periodicity.The dominant frequency of the pressure fluctuation near the inlet of the deflector is double the blade passing frequency(BPF)under non-cavitation condition.The dominant frequency of the pressure flucutation at the other monitoring points is BPF under both cavitation and non-cavitation conditions.The amplitude of the pressure fluctuation near all the monitoring points increases significantly under cavitation condition.
杨敬江*,李先军,潘中永,何松. 双蜗壳离心泵空化流动对隔舌处压力脉动特性的影响[J]. 排灌机械工程学报, 2020, 38(5): 445-450.
YANG Jingjiang*,LI Xianjun,PAN Zhongyong,HE Song. Effects of cavitating flow on induced pressure fluctuation near cutwaters in double-volute centrifugal pump. Journal of Drainage and Irrigation Machinery Engin, 2020, 38(5): 445-450.
