Effect of inducer deflection angle on impeller cavitation performance in centrifugal pump
LI Rennian1,2, BI Zhen1, LI Yibin1,2, XIAO Liqian1
1.School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China; 2.Key Laboratory of Fluid Machinery and Systems, Gansu Province, Lanzhou, Gansu 730050, China
Abstract:In order to clarify the effect of inducer deflection on cavitation performance of centrifugal pump impeller, improve centrifugal pump cavitation performance, and get the best circumferential position, based on the homogeneous flow assumption, the IDM cavitation model and the RNG k-ε turbulence model were adopteed and five projects which deflections are 0°,10°,20°,30°,40° and 50° were selected,to compare numerical simulation values and experimental values of pump′s external characteristics and cavitation performances of inducer and impeller. The centrifugal pump characteristic performance data of different projects were obtained. Calculated NPSHR curves match well with experimental ones, which can verify the accuracy of the calculation methods. Based on numerical simulation results, vapor volume fraction distributions within inducer and impeller blades under various conditions were analyzed.It was found that cavitation bubbles′ development processes and rates of 10° and 20°positions are basically the same, but the cavitation rate and vapor volume fraction distribution areas are smaller when the deflection is 10°, therefore two deflectians of 5° and 15° were further selected to do simulation analysis to get more accurate results, i.e. the pump′s overall hydraulic characteristic is the best when the deflection is 5°.
李仁年,, 毕祯, 黎义斌,, 肖丽倩. 诱导轮偏转角对离心泵叶轮空化性能的影响[J]. 排灌机械工程学报, 2016, 34(6): 461-469.
LI Rennian,, BI Zhen, LI Yibin,, XIAO Liqian. Effect of inducer deflection angle on impeller cavitation performance in centrifugal pump. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(6): 461-469.
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