Investigation of Effective Parameters on the Hydrofoil Performance near the Free Surface of Water

In this study, a numerical method is used to assess the effect of thickness, camber, submergence depthand flow velocity around a submerged hydrofoil. A pressure based algorithm is used to solve Navierstokesequations, and Volume of Fluid (VOF) approach is applied to simulate two-phase fluid (waterand air). The model and second order upwind scheme have been used for turbulence models anddifferential schemes, respectively. For verifying, a part of results is compared with publishedexperimental results. The numerical and experimental results show excellent agreement; thus, theprocess of numerical simulations is confirmed. The results of this study illustrate that the lift and dragcoefficients increase with rising the thickness of the hydrofoil, but the lift to drag ratio has adownward trend. On the other hand, the lift and drag coefficients increase with growing the camber ofthe hydrofoil, but lift to drag ratio has upward trend. Therefore, to opt the best section of the hydrofoil,the less thickness and the high camber are more desirable to getting high hydrodynamic performance.The switched of the hydrofoil section obviously affects the airflow and boundary layer formed on thefree surface of water. Moreover, lift and drag coefficients become high by increasing the submergencedepth and angle of attack, as a result lift to drag ratio increases. Lift and drag coefficients aredecreased by increasing flow velocity, and lift to drag ratio has a downward trend.