Numerical study of the tip vortex flow over a finite-span hydrofoil

The flow over a finite-span hydrofoil creating a tip vortex was numerically studied by computing the full Navier-Stokes Equations. Favorable comparison was achieved between the numerical solution and available experimental data. The steady-state roll-up process of the tip vortex was described in detail from the numerical results. The effect of the angle of attack, the Reynolds number, and the hydrofoil planform on the tip vortex was investigated. The axial and tangential velocities within the tip-vortex core in the near-field wake region was greatly influenced by the angle of attack. An increase in the axial velocity within the tip-vortex core was found at high angle of attack while a decrease in the axial velocity was found at low angle of attack. Increasing the Reynolds number was found to increase the axial velocity but only had a slight impact on the tangential velocity. Finally, a swept hydrofoil planform was found to attenuate the strength of the tip vortex due to the low-momentum boundary layer traveling into the tip vortex on the suction side.