원심 펌프 임펠러의 생체모방공학 기반 최적화 연구: 입구 유동 조건의 영향

초록

We aim at analyzing the mechanism of passive flow control by a biomimetic tubercle shape for impeller trailing edge(TE) in a centrifugal pump and the effect of inflow conditions. A shape optimization process of tubercle heights was performed for two different inflow conditions that approximate the conditions of a three-stage centrifugal pump. The composite efficiency of the pump increased by up to 0.77%. Compared to the streamwise periodic condition, the inflow-outflow condition showed larger increase in the pump efficiency and decrease of the turbulent intensity. Among different tubercles along TE, a specific tubercle had a relatively large effect on the results. Vortex structures were examined using the Q-criterion and swirling strength. It was observed that the orientation of the vortices behind TE changed from spanwise to streamwise by the tubercle TE. Counter-rotating streamwise vortices were generated at the top and bottom of each tubercle, and the interaction of the vortex pair led to vortex breakdown, resulting in a decrease in the turbulent intensity.

키워드