2016 Volume 5 Issue 1 Pages 1-9
Underwater propulsion using a flexible elastic fin that mimics fish locomotion is investigated. Because the degree of elasticity is important for thrust efficiency, a fin with a dynamic variable-effective-length spring as a variable-stiffness mechanism is experimentally analyzed. The yawing of the elastic fin in still water is simulated using fluid-structure interaction analysis. There is a clear relationship between the effective length of the spring and Young's modulus for the dynamic stiffness of the fin. Additionally, using the kriging surface response approach, thrust efficiency is demonstrated to be better under dynamic conditions.
