Numerical investigation of hydrodynamics of flapping caudal fin

This paper investigates the hydrodynamic performance of flapping caudal fin by means of numerical simulation. Dynamic simulations of caudal fin with heaving and pitching motion are conducted to determine the relationship between the maximum angle of attack and difference of phase angle in terms of thrust coefficient and propulsive efficiency under low frequency. Combing 20°~30°maximum angle of attack with 70°~90° difference of phase angle, outstanding propulsive efficiency can be obtained. In addition, qualitative analyses are made to the wake vortex spacing. This study shows that wake spacing has interaction with the thrust coefficient and the propulsive efficiency.