Investigation On Cavitation Characteristics Of Hydrofoil And Propeller Based On OpenFOAM

In this paper,the cavitation flow of different hydrofoils and propellers is successfully simulated based on the open source platform OpenFOAM.The research of hydrofoil cavitation is simulated by inter Phase Change Foam,which is a phase change solver supplied with openFOAM.The effects of different cavitation models,different turbulence models,different cavitation numbers and different mesh generation methods on hydrofoil cavitation simulation are discussed.The numerical simulation results of lift/drag coefficient,cavitation shedding frequency and the periodic development of cavitation from generation to collapse are in good agreement with the experimental results.Considering the effect of the re-entrant jet on the sheet cavitation,an obstacle is added to the suction surface of the hydrofoil to block the reentrant jet upward.It is found that the pressure distribution on the suction surface of the hydrofoil can be changed by properly arranging the obstacle in the cavitation area,and the low pressure area formed downstream of the obstacle can increase the pressure difference between the upper and lower surfaces of the hydrofoil,thereby increasing the lift coefficient.In order to solve the problem that the cavitation simulation depends deeply on the grid quality,the adaptive grid refinement technology is used to improve the physical resolution of the cavitation flow phenomenon.During the evolution of the cavitation shape,including the generation,development,deformation and final collapse of the cloud cavitation,the adaptive grid can capture the phase interface very well.Meanwhile,it can reduce the amount of unnecessary grid,avoid grid waste,and improve the efficiency of calculation.For the numerical simulation of propeller tip vortex cavitation,the inter Phase Change Dy MFoam,a dynamic grid solver of openFOAM,is used for the simulation.In order to solve the problem that propeller tip vortex cavitation is more sensitive to grid quality,a new grid generation method is adapted to capture the tip vortex cavitation of propeller.