Vortex shedding simulation of hydrofoils with trailing-edge truncation

Abstract

Vortex shedding behind hydrofoils with trailing-edge truncation was analyzed via numerical simulations. The NACA0009 hydrofoil was analyzed numerically using the Spalart-Allmaras turbulence model. The hydrofoil lift coefficient variation curve was monitored during the simulation, and the vortex-shedding frequency was obtained as the oscillation frequency of the lift coefficient curve. The mode of vortex shedding of the perpendicular truncated and oblique truncated trailing edges were compared. The vortex-shedding behavior under different oblique truncation angles and the impact of the angle of attack on vortex shedding were also explored. The results showed that the oblique truncated trailing edge can substantially change the intensity and frequency of vortex shedding of the hydrofoil. Furthermore, there exists an oblique truncation angle at which the vortex-shedding frequency is minimized. In the presence of an angle of attack, the hydrofoil with oblique truncated trailing edges was less affected by vortex shedding from the tail.