Computational Fluid Dynamic Study on the Effect of Winglet Addition in Flapping Hydrofoils to Evaluate the Propulsive Performance of Wave Gliders

Wave Gliders have specific arrangements that convert up/down wave motion into forward propulsion. These arrangements consist of an array of hydrofoils that are pivoted to pitch within a certain range of motion. Several attempts have been made by researchers to improve the propulsion efficiency of wave gliders, some of which include: modifying hydrofoil profile, inducing asymmetry in hydrofoil pitching (flapping), varying the spacing between hydrofoils, etc. In this research work, we study the effect of adding winglets to the hydrofoils. The winglets are meant to reduce tip vortices that typically occur at hydrofoils and hence improve propulsion efficiency. Computational fluid dynamic studies have been carried out to assess the effect of adding winglets to the hydrofoil. Results show that addition of a winglet to a flapping hydrofoil improves the thrust coefficient.