Analyzing the problems in the numerical simulation for inner flow by original turbulence model in rotary machines
it is found necessary to totally consider the effects of rotation and curvature for enhancing the numerical accuracy and improving instability of centrifugal pump inner flow. The effects of rotation and curvature in k-ω SST model are taken into account
and a modified turbulence model based on Richardson number from Hellsten is Built. Then the improved turbulence model is adopted to simulate the steady-state inner flow in a centrifugal pump at specific speed of 34.34 under different operating conditions. A comparison between the experimental data and numerical results from the original and modified models reveals t
he law of pump inner flow. The hydraulic performance predicted by the improved model gets closer to the experimental results than that by original one. In the case of the flow rate of 0.6Q
d
the head accuracy and the precision of efficiency predicted by the improved turbulence model increase by 3% and 2%
respectively. The inner flow of pump under 0.6Q
d
verifies the superiority of the improved turbulence model
and the turbulent flows both in impeller passages and diffusor are improved obviously.
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