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Based on the RNG k-ε turbulence model and Reynolds-averaged N-S equation, the CFD software was used to simulate the three-dimensional flow value of axial flow pump device for bell-type inlet channel and design the hydraulic performance optimization. Firstly, the bell-type inlet channel was optimized through the part to overall method, and then the elbow outlet channel of the whole pump device was optimized, three-dimensional parametric modeling can be made for the inlet and outlet flow channel. The inlet flow channel took the outlet section velocity uniformity and the hydraulic loss as the objective function. At the same time, the outlet flow channel took the pump device efficiency as the objective function. According to the design flow conditions and the control parameters numerical simulation of the inlet and outlet flow channels, the influence of different control sizes on the hydraulic performance of inlet and outlet channels can be analyzed. Finally, the reliability of the numerical results of the optimization scheme was verified by the model test. Numerical simulation and model test showed that by optimization the flow can be improved. After optimization, the hydraulic loss of the bell-type inlet channel was reduced from 0.348m to 0.148m, while the outlet velocity uniformity was increased from 54.59% to 93.35%. Also, the hydraulic loss of the elbow-type outlet channel was reduced from 0.464m to 0.415m.When the model pump device test in the blade placement angle was 0°, the design conditions efficiency can be up to 74%. The maximum efficiency was 7647% and the high-efficient operating range was wide. There was no whirlpool produced in both inlet and outlet channels with uniform flow. The error of the external characteristic curve was less than 5% in the simulation and model test. The hydraulic loss curve of the inlet channel was also the same. The less hydraulic losses of the inlet and outlet flow channels after optimization, indicated that the numerical simulation involved in the optimization of the pump was reasonable and reliable. Using the numerical simulation to optimize the calculation of the axial flow pump of the bell-type inlet channel can shorten the test cycle and save the cost. It also can guide the engineering application accurately and reliably, and provide reference for the design and safe operation of the similar pump station. 