Study on dynamic performance of wave-powered boat under the action of ocean current

Abstract

Wave-powered boat will be affected by the ocean current when moving forward. In order to study the impact of the ocean current on the dynamic performance of wave-powered boat, the fluid-multibody coupled model of the hydrofoil was established in FLUENT through the dynamic mesh method. The hydrodynamic force and moment of the hydrofoil were introduced into the rigid body dynamic equation of the boat, the motion parameters at that time can be calculated by numerical integration to achieve coupling process. The results shows that, with the increase of counter-current velocity, the propulsion velocity of the wave-powered boat and hydrofoil rotation angle both decrease. The results in co-current conditions are more complicated and the rear hydrofoil will be affected by the superposition of the current and the wake vortex falling off from front hydrofoil, causing fluctuations in its rotation process. Beside, the restoring stiffness has an important influence on the propulsion performance of wave-powered boat, so it is necessary to select the appropriate restoring stiffness to improve the propulsion performance of the device under different current velocities.