난류모델에 따른 반구형 실린더 주위 캐비테이션 유동 현상 해석

Abstract

Cavitation is a significant topic as it leads to erosion of marine propellers and induces noise and vibration within the entire mechanical system. The present study compares cavitation flows around a 3D hemispherical head-form body using the Reynolds-averaged Navier-Stokes (RANS) and the partially averaged Navier-Stokes (PANS) models. These turbulence models play an important role in observing the unsteady characteristics of cavitation flows. To examine the influence of these turbulence models on such flow characteristics, we analyzed a periodic shedding of the sheet, cloud cavitation. In addition to the cavity shape around the body, pressure, velocity, turbulent kinetic energy, and turbulent viscosity were compared to identify differences caused by the turbulent models. For this analysis, an open-source computational fluid dynamics (CFD) toolkit OpenFOAM was utilized. The results showed that the pressure coefficient in the PANS model is in good agreement with experimental results compared to the RANS model. Furthermore, the development process of sheet/cloud cavitation was observed in the PANS model.