首先,运用Zwart空化模型和湍流粘度修正后的RNG湍流模型对有口环间隙和无口环间隙时离心泵的空化性能进行了数值模拟,研究发现:有/无口环间隙时离心泵的“扬程-有效汽蚀余量”曲线都与实验曲线变化一致,但是有口环间隙时的曲线与实验结果更接近.然后,对前口环间隙分别为0.2 mm、0.5 mm、0.9 mm、1.3 mm和1.6 mm时离心泵的空化性能进行了数值计算,研究表明:有效汽蚀余量大于等于2.15 m时,前口环间隙增大会使叶轮上空化面积减小,对离心泵的空化性能有利;有效汽蚀余量小于等于2.05 m时,前口环间隙增大会导致叶轮上空化面积增大,对离心泵的空化性能不利.%By using Zwart cavitation model and RNG turbulent model with turbulence viscosity modified,cavitation performance of a centrifugal pump with or without wear-ring clearance is numerically simulated.The simulation result demonstrates that " head-NPSHa" curves of the centrifugal pump with or without wear-ring clearance all have similar trends with the experimental ones,while the curves with wear-ring clearance more conform with the experimental results.Secondly,cavitation performance of the centrifugal pump with different gaps of front wear-ring clearance (0.2 mm,0.5 mm,0.9 mm,1.3 mm and 1.6 mm) is numerically calculated respectively.Calculation results show that the increase of the gaps leads to the decrease of cavitation area on impeller when NPSHa is equal to or greater than 2.15 m,which is beneficial to cavitation performance of the centrifugal pump,and the increase of the gaps leads to the increase of cavitation area on impeller when NPSHa is equal to or less than 2.05 m,which is harmful to the cavitation performance of the centrifugal pump.
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