Study on the influence of non-equidistant blade arrangement on the performance of centrifugal pumps

In bladed machinery, discrete noise comes from the interference between the moving and stationary blade rows. Although the flow stability can be enhanced by improving the coupling structure parameters between the impeller and the pump casing, this method usually affects the performance of the bladed machinery seriously. Thus, the pressure fluctuation characteristics inside the in-orbit refueling propulsion pump can be improved by changing the blade arrangement. In centrifugal pumps, non - non-equidistant blade arrangement can reduce pressure-pulsation amplitude at the blade frequency, thus enhancing flow stability. In this paper, non - equidistant and equidistant blade models were designed using the non - equidistant blade arrangement method. The differences in their external characteristics were explored with the internal flow field and entropy-generation theories. Unsteady calculations were performed on both models under the same conditions. Pressure-pulsation characteristics in single-phase and cavitating flows were compared and analyzed.