Optimal Design of a Non-Overload Centrifugal Pump

Three experiment factors including outlet blade angle β2, b2 and impeller wrapping angle θ are selected for optimal design of a non-overload pump. Numerical simulation with CFD is employed to reduce the cost and shorten the design period. The time-averaged Navier-Stokes equations of 3D steady flow in the pump are calculated by CFD based on the SST k-ω turbulence model and standard wall function. The structured grids of different qualities are used in one scheme for comparison to confirm that the results are not influenced by the quality of mesh. The optimal scheme is obtained when β2, b2, θ are 20 degrees, 7mm, 170 degrees, respectively. Its pressure head is 89.75m achieving the pump efficiency of 57% at maximum. The performances of NCPs at other working conditions satisfy the requirement of heads and efficiencies from China National Standard. The shaft power reaches to 15kW at 1.5QR (35.5m3/h), showing that the non-overload performance is also significantly improved. The impeller is considered as the optimal scheme and produced for experiments. Experiment data prove that it is effective and reliable to improve a non-overload pump’s performance by maximum flow design method and non-overload pump design method. The results provide a reference for increasing the efficiencies and pressure heads of non-overload pumps at multiple operating conditions.