Effect of Interaction of Flapping Hydrofoil Motion Parameters on Thrust Pulsation Performance

Abstract

This study presents a novel index to assess the thrust propulsion performance of flapping-hydrofoil, and identifies the order of priority of motion parameters that affect the thrust pulsation amplitude. The flapping motion is simulated using the Udf (user-defined motion) feature in the commercial software Fluent, and the impacts of three flapping motion parameters on flapping thrust are investigated by manipulating these parameters. The results of the numerical simulation indicate that there is a positive correlation between the heave amplitude and the thrust pulsation amplitude. Additionally, the thrust pulsation amplitude is interactively affected by the pitch amplitude, the phase difference between horizontal and heave motion, and the heave amplitude. The Levenberg-Marquardt Algorithm is employed to fit the function that relates the thrust pulsation amplitude with the three motion parameters. The coefficients obtained from the fitting function indicate the impacts of the interaction effect, as well as the effect of each motion parameter on the pulsation amplitude.