Meeting Abstract

18.6  Thursday, Jan. 3  Hydrodynamic perfomance of the minke whale (Balaenoptera acutorostrata) flipper COOPER, Lisa Noelle*; SEDANO, Nils; JOHANSSON, Stig; MAY, Bryan; BROWN, Joey D.; HOLLIDAY, Casey M.; FISH, Frank E.; NEOUCOM, Ohio; Air Force Research Laboratory, Liquid Engineering Branch; San Diego State University, San Diego, CA; none; NASA, Jet Propulsion Laboratory; Joan C. Edwards School of Medicine, Huntington, WV; West Chester University, West Chester, PA l.noelle.cooper@gmail.com

Minke whales (Balaenoptera acutorostrata) are baleen whales with narrow and elongated flippers that are small relative to body size compared to related species such as right and gray whales. No experimental studies have addressed the hydrodynamic properties of the flippers of minke whales or other cetaceans with similar flipper morphologies. This study integrated windtunnel, locomotor, and range of motion data to identify functional parameters of the minke whale flipper. A cast of a minke whale flipper was used in windtunnel testing of lift, drag, and stall behavior at six speeds, corresponding to swimming speeds of 0.7-8.9m/s. Flow over the model surface stalled between 10-14 degrees angle of attack depending on testing speed. When the flipper leading edge was lowered, loss in lift occurred around -18 degrees angle of attack regardless of speed. Range of mobility in the fresh limb was approximately 40% greater than the range of positive lift-generating angles of attack predicted by windtunnel data. Swimming, feeding, and gulping minke whales were observed in movies and photographs with limb positions corresponding to the least drag, and were therefore hydrodynamically efficient. Flippers may play an important role in engulfment feeding as they possibly increase pitch of the body during water and prey uptake.