Blade exit angle impact on turbulent fluid flow and performance of centrifugal pump using CFD

Rotor is a working part that adds energy to the fluid; its geometry plays a fundamental role in the centrifugal pump performance. Any change in the rotor geometry would have an effect on the impeller inlet or exit velocity triangles, which may cause a significant performance change. Hence the blade exit angle have very important role in the performance of the centrifugal pump. In this paper three impeller designs that differ in their outlet blade angles, with the casing and other geometric parameters keep constant, are considered to investigate its effect on the flow parameters and turbulence intensity as well as on the performance of the centrifugal pump. For this purpose, a three-dimensional flow is simulated solving Reynolds averaged Navier Stokes (RANS) equations by using FLUENT code. Standard k-e model is used for the turbulent closure of steady incompressible flow. The CFD analysis shows that the blade exit angle has influence on the head and efficiency. Rise in head and hydraulic efficiency have been observed with increasing blade exit angle. The research results are helpful for energy efficiency and hydraulic design of centrifugal pump.