Numerical analysis for inner flow field in a centrifugal pump under maximum operating conditions

ZHANG Chi-xiang1，LI Yi1，ZHANG Yu-liang2

（1. The Zhejiang Key Lab of Fluid Transmission Technology，Zhejiang Sci-Tech University，Hangzhou 310018，China； 2. College of Mechanical Engineering，Quzhou University，Quzhou 324000，China）

Abstract：Aiming at studying the inner flow under maximum operating conditions，a centrifugal pump was simulated by adopting RNGκ-ε turbulence model. Hydraulic performance was predicted and the calculation results were compared with the experiment results. Fluid velocity，pressure distribution and external characteristics were analyzed under 4 operating conditions. The results indicate that pressure and velocity distribute uniformly under the optimum flow rates condition. At large flow rates point，the volute pressure decreases and the velocity distribution is not uniform. At the maximum flow rates point（1.7 Qopt），negative pressure appears at the inlet of the volute. Vortex of the velocity flow lines become larger and occurs reflux in the local position of diffusion tube. The study reveal pump inner flow rules，which provide reference to the high specific speed centrifugal pump optimal design and extending service life under variable flow rates operating conditions.