Numerical Study of Effect of Asymmetry on Performance of Bio-mimetic Caudal Fin Shapes

Bio-mimetic propulsion systems are recently being explored for autonomous underwater vehicles (AUVs) and autonomous surface vehicles (ASVs). Many studies are conducted for adopting Body–Caudal Fin propulsion systems to AUVs and ASVs. This primitive study aims to numerically analyse the effect of asymmetry on the thrust developed by six caudal fin designs inspired by the asymmetry of shark fins. The fins are divided into two sets, one with constant fork angle and other with varying fork angle. The fins are assumed to be of the same area in order to eliminate the effect of area on thrust developed. Through computer simulations, it is observed that the asymmetry causes the average thrust to decrease. But from two cases studied, the forking angle has an influence on thrust generated. The variation of thrust during a cycle is less in case of asymmetry.