Meeting Abstract

S5.11  Wednesday, Jan. 5  The humpback whale flipper for application of bio-inspired tubercle technology FISH, F.E.; West Chester Univ., Pennsylvania ffish@wcupa.edu

The humpback whale (Megaptera novaeangliae) is exceptional among the large baleen whales in its ability to undertake aquabatic maneuvers to catch prey. Humpback whales utilize extremely mobile, wing-like flippers for banking and turning. Large rounded tubercles along the leading edge of the flipper are morphological structures that are unique in nature. The leading edge tubercles act as passive-flow-control devices, which improve flipper performance and maneuverability. Experimental analysis of finite wing models has demonstrated that the presence of tubercles produces a delay in the angle of attack until stall, increase maximum lift and decreased drag. Possible fluid dynamic mechanisms for improved performance, including stall delay through vortex generation and boundary layer modification, and increase in effective span by reduction of both spanwise flow and strength of the tip vortex. The tubercles provide a bio-inspired design that has commercial viability for wing-like structures. Passive flow control has advantages of eliminating complex, costly, high-maintenance, and heavy control mechanisms, while improving performance for lifting bodies in air and water. The leading edge tubercles can be applied in the design of water- and aircraft, ventilation fans and windmills.