Effects of variable pitch inducer on cavitation performance of highspeed centrifugal pumps
SUN Qiangqiang1, JIANG Jin1, 2, ZHANG Shuaishuai1, CHEN Qi3
1.School of Power and Mechanical Engineering, Wuhan University, Wuhan, Hubei 430072, China; 2.Key Lab of Hydraulic Machi-nery Transient, MOE, Wuhan University, Wuhan, Hubei 430072, China; 3. Hubei Water Resources Research Institute, Wuhan, Hubei 430070, China
Abstract：In order to study the effect of geometry shape of variable pitch inducer and coordination between inducer and impeller including axial distance and circumferential angle on the cavitation perfor-mance of the high-speed centrifugal pump, the turbulence model of RNG k-ε and cavitation model of Schnerr-Sauer were used to investigate the cavitation performance of high-speed centrifugal pump with different inducers at diverse coordination conditions. The results show that the variable pitch inducer which the blade diameter is constant can suppress the cavitation of the high-speed centrifugal pump more effectively compared with the variable pitch inducer with variable blade diameter. When the distance between inducer and impeller is too small or too large, the pressure coefficient and cavitation number of inducer decrease and the vapor volume ratio in the impeller flow channel has an upward trend. As a result of that, efficiency and lift coefficient of the high-speed centrifugal pump decrease. In addition, the cavitation performance of the pump fluctuates as the circumferential angle changes, however the change regularity is not obvious.
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