| Centrifugal pumps are widely used in many different field, such as industry, agriculture and so on. The flow performance of centrifugal pumps has substantial influence on the design of the pumps, and is important for improving the operating characteristics of the pumps. The realization of numerical simulation of internal flow of centrifugal pumps has not only theoretical significance, but also practical value in engineering.For the past few years, along with the development of computational fluid dynamics technology, studying the internal flow mechanism of centrifugal pumps with using numerical simulation technology, and conducting the pump design by using numerical simulation results have became an important research orientation. Using numerical simulation method, on the one hand, can save test resources, and shorten the time of developmenting new product. On the other hand, it can get the fluid flow in details which are difficult to obtain in test. Also, with the rapid increase of operation speed and amount of memory of computer, more turbulence models and calculation method were applied to 3D flow calculation of the centrifugal pump, which made the three-dimensional flow calculation of turbulence models continuously to develop.But until now, there is no general model, because different different situations need different turbulence models. Choosing appropriate and accurate turbulence model has important influence on the calculation precision and the degree of calculation difficulty. How to get the appropriate model consistent with the actual situation remains to be further discussed and studied.In this study, the IS150-125-250 centrifugal pump was chosed as the research object. Four different turbulence models were used in the calculation of three-dimensional flow in impeller of the centrifugal pump. At first control equation was established according to the internal flow field of the centrifugal pump. Then, the characteristics and applied range of standard k-εmodel, RNG k-εmodel, shear stress transmission SST k-ωmodel and standard k-ωmodel were introduced. Afterthat, the three-dimensional modeling software Pro/ENGINEER was used to establish 3D solid model of the selected centrifugal pump. By using unstructured grid and SIMPLEC algorithm, numerical simulation and performance prediction of internal flow were conducted on five working conditions of IS 150-125-250 centrifugal pump with above-mentioned models. Pump lift, efficiency of pumps and shaft power were also calculated. The results show that calculation results of turbulence models are basically consistent with experimental curves. In design condition, calculation results and experimental results are relatively close. Whereas, when not in the design condition, the disparity between calculation results and experimental results are relatively larger. The calculation accuracy of SST k-ωmodel is the highest. The calculation accuracy of RNG k-εmodel is slightly higher than the calculation accuracy of standardd k-εmodel. The calculation accuracy of standard k-ωmodel is worse.Through analysis of the internal flow field in different working condition, a conclusion can be obtained that when not in the design condition, the field distribution is poorer. But in the design condition, the distribution of low is better ang more reasonable in accordance with the actual situation, which proved that calculation method we used has higher reliability, and the SST k-ωmodel is suitable for flow field calculation and performance prediction of chosed pump.
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