Effect of kinematic behavior of caudal fin on fishlike robot propulsion during steady swimming

The speed convergence algorithm is applied in the numerical simulation of a fishlike robot in self-propelled swimming. All simulations are started with the body at rest, the swimming speed is dynamically modified to converge to the steady value by verifying the fluid forces during the swimming process. The effects of kinematic behavior of caudal fin on fishlike robot propulsion are numerical investigated in the converged steady speed, while the propulsive mechanism and flow field structure are revealed. The results show that the steady speed can be predicted validly by using the speed convergence algorithm, while the relation between the kinematic behavior and the propulsion, power consumption and propulsive efficiency can be obtained through varying the phase difference and the maximum angle of attack. The effects of kinematic behavior of caudal fin on the wake structure and wake strength are clearly reflected in the three dimensional flow field structures. The findings are of great significance to the swimming speed prediction, effect of kinematic behavior on fishlike robot propulsion as well as the motion parameter design for fishlike robot.