Low cost simulations for centrifugal pump noise

Air and fluid movers such as fans, blowers, pumps and compressors are efficient and relatively compact. The rotating impeller blades cut through the fluid resulting in flow pulsations at regular intervals causing the tonality and stochastic fluctuations causing the broad-band changes. The regularity is governed by rotating speed and number of blades. These disturbances propagate through the medium and eventually perceived as noise or vibrations of the structural components (housing, shafts, ...). In this paper, the authors combine computationally less expensive U-RANS (unsteady Reynolds Averaged Navier-Stokes) analysis for the flow simulation with finite element acoustics for the noise propagation. The goal is to predict noise generated by the pump on the inlet (louder) side at a specified operating rotation speed. Though the focus is capturing the primary tones, the authors show decent comparison with measurements across the frequency spectrum.