Eddy vorticity in cavitating tip vortices modelled by different turbulence models using the RANS approach

VTT Technical Research Centre of Finland and Aalto University have been investigating numerical simulation of cavitating propellers. Special emphasis is placed on the simulation of cavitating tip vortices. The simulations are performed with the k-ε, SST k-ω and EARSM turbulence models in wetted and cavitating conditions. The calculations are performed in uniform inflow. The propeller performance characteristics and the wake velocities in the wetted conditions were compared to the measurements. Additionally, the simulated cavitation extent on the propeller was compared to the measurements. Good correlation between the tests and simulations were found. The turbulence models gave significant differences to the tip vortex core solutions in wetted and cavitating conditions. The k-ε model gave high non-dimensional Reynolds stresses both in wetted and cavitating conditions. The anisotropic EARSM model gave the lowest Reynolds stresses in the wetted conditions in the vortex core. In cavitating conditions the SST k-ω and EARSM models gave very low Reynolds stresses to the vaporous vortex core