Key Laboratory of Fluid Transmission Technology of Zhejiang Province, Zhejiang Sci-Tech University, Hangzhou, 310018, China
The rotor-stator interaction between the impeller and the volute is the main reason for the pump pressure pulsation and vibration. This work aims at designing a new type of tongue to minimize pressure pulsation, reduce vibration noise and energy loss. Inspired by the humpback pectoral fin, four volute tongues are investigated in this paper, three of which are sinusoidal tubercle volute tongues (STVT) and one is the original volute tongue (OVT). Based on the detached-eddy simulation (DES) turbulence model, the influence of the sinusoidal tubercle volute tongues on the pressure pulsation was investigated, and the flow structure and enstrophy of the four pumps were analyzed, aiming to minimize pressure pulsation, maximize hydraulic performance and reduce the energy dissipation in centrifugal pumps. The results show that the pressure pulsations of the STVT profiles are all lower. The reductions of the average pressure pulsation at the monitoring points are 13.3% (STVT-1), 20.6% (STVT-2), and 16.2% (STVT-3), respectively. The difference in pressure pulsation at the monitoring points closer to the tongue is more obvious. At the design flow rate, the efficiencies of the three bionic pumps are increased by 0.5% (STVT-1), 1.5% (STVT-2), 0.9% (STVT-3), respectively. The STVT profiles change the vortex structure near the tongue and minimized the vortex strength. Meanwhile, the flow in the pump with the STVT profiles have lower enstrophy. The enstrophy of the flow with the STVT-2 profile is the lowest, which is reduced by about 8%. This reduces the dissipation of mechanical energy. The results can be used as a guide for pump design optimization.