Abstract：To study the influence of the initial stage centrifugal impeller on the performance and internal flow characteristics of a radial vane multi-stage side channel pump with low specific speed, an unsteady three-dimensional numerical simulation was carried out using the SST-SAS turbulence model on a single-stage and multi-stage side channel pump under different working conditions. The results revealed that the head of the multi-stage side channel pump improves after adding the centrifugal impeller as the first stage. The inlet pressure of the side channel impeller increases by 20%, the mass flow between the impeller and the side channel is also increased by about 20%. However, the distribution of vortices in the impeller of the multi-stage side channel pump is basically the same as that of single-stage and the addition of the centrifugal impeller as the first stage has little effect on the internal flow characteristics of the single-stage pump. The findings of this research paper provides a reference and theoretical basis for subsequent cavitation research and structural optimization of multi-stage side channel pumps.
