Cavitation Evolution and Excited Pressure Fluctuation around Twisted Hydrofoils and Marine Propellers by CFD Analysis
Speaker: Professor Yulin Wu, Tsinghua University, Beijing, China
Department: Mechanical & Aerospace Engineering
Location: Engineering Quadrangle J223
Date/Time: Wednesday, January 16, 2013, 2:30 p.m. - 3:30 p.m.
Cavitation phenomena consist of a complex combination of fluid dynamics and bubble/cavity mechanics. The unsteadiness of cavitation can therefore significantly induce pulsation in the hydrodynamic performance and pressure fluctuations. In order to gain a better understanding of the complex physics involved, unsteady cavitating flow simulation around twisted hydrofoils and marine propellers were carried out by CFD analysis. Twisted hydrofoil was selected to study 3D cavitating flow structures for some operating conditions. We also studied unsteady cavitating flows around marine propellers in non-uniform wake. The results described in both cases were intended to shed light on the physical processes responsible for the pressure fluctuation excited by the cavitation evolution (lower frequency component only). The cavitation evolution, especially cavity volume, was related to the pressure fluctuations. The results show that the acceleration due to the cavity volume change is the main source of the pressure fluctuations. The simulation agrees well with preliminary experimental results.