Numerical analysis of the unsteady flow in an axial-flow pump at design and off-design conditions

The internal flow of an axial-flow pump has been simulated by using the curvature corrected filter-based turbulent model (FBM-CC). Compared with the experimental results, the FBM-CC could effectively predict the hydraulic performance of the pump. The complex turbulent flow fields in the axial-flow pump at three typical flow rate conditions have been investigated. The numerical results show that the serious blockage in the impeller passage, which caused by the prerotation at the upstream of impeller, the separated flow on the blade and the reverse flow from the diffuser, leading to the formation of saddle zone at the off-design condition.