In order to study the cavitation and hydrodynamic characteristics of propeller under uniform and non-uniform flows, numerical investigations are performed using interPhaseChangeDyMFoam in the open source computational fluid dynamics (CFD) software platform OpenFOAM with Schnerr-Sauer cavitation model. The simulation results can be used as a reference to evaluate the working ability of a propeller in case of actual navigation. A new grid encryption method is adopted in the research to better capture the existence of vortex cavitation at the propeller tip. The method of function input is carried out in the study to simulate the condition of non-uniform flow and reduce the calculation amount. Typical unsteady dynamics are predicted by the Reynolds-averaged Navier-Stokes (RANS) method with a modified shear stress transport (SST) -k  turbulence model. The numerical results of the propeller such as cavitation shape and pressure distribution under uniform and non-uniform flow are analyzed and compared with each other.

The present work focuses on the comparison of the numerical simulation of sheet/cloud cavitation with the Reynolds Average Navier-Stokes and Large Eddy Simulation(RANS and LES) methods around NACA0012 hydrofoil in water flow. Three kinds of turbulence models—SST k-ω, modified SST k-ω, and Smagorinsky’s model—were used in this paper. The unstable sheet cavity and periodic shedding of the sheet/cloud cavitation were predicted, and the simulation results, namelycavitation shape, shedding frequency, and the lift and the drag coefficients of those three turbulence models, were analyzed and compared with each other. The numerical results above were basically in accordance with experimental ones. It was found that the modified SST k-ω and Smagorinsky turbulence models performed better in the aspects of cavitation shape, shedding frequency, and capturing the unsteady cavitation vortex cluster in the developing and shedding period of the cavitation at the cavitation number σ = 0.8. At a small angle of attack, the modified SST k-ω model was more accurate and practical than the other two models. However, at a large angle of attack, the Smagorinsky model of the LES method was able to give specific information in the cavitation flow field, which RANS method could not give. Further study showed that the vortex structure of the wing is the main cause of cavitation shedding.

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