Drag Reduction in a Swimming Humboldt Penguin, Spheniscus Humboldti, when the Boundary Layer is Turbulent

An area of protruding feathers found around the beak of many penguin species is thought to induce a turbulent boundary layer whilst swimming. Hydrodynamic tests on a model Humboldt penguin, Spheniscus humboldti, suggest that induced turbulence causes a significant reduction in boundary layer height, flow separation, and an average of 31% reduction in drag (1.0 m/s to 4.5 m/s). Visualisation of surface flow showed it to follow the body profile, over the feet and tail, before separating. Movement of the feet in swimming penguins correlates with steering of the bird. Induced turbulence may therefore further increase swimming efficiency by reducing the amount of foot movement required to direct the swimming bird.

作 者： Alex R. Parfitt Julian F.V. Vincent   作者單位： Centre for Biomimetic and Natural Technologies, Department of Mechanical Engineering, The University of Bath, Bath, BA2 7AY, UK  刊 名： 仿生工程學報（英文版）  SCI 英文刊名： JOURNAL OF BIONICS ENGINEERING  年，卷(期)： 2005 2(2)  分類號： Q81 TB17  關鍵詞： drag   drag reduction   boundary layer   turbulence   penguin   Spheniscus humboldti (Sphenisciformes)  

【Drag Reduction in a Swimming Humbold】相關文章：

Drag Reduction for an Airship with Proper Arrangement of Propellers04-30

·Swimming 游泳05-04

Experimental study on Cr(Ⅵ) reduction by Pseudomonas aeruginosa04-25

游泳也瘋狂：好&壞? Swimming05-04

第98講：put on the back burner; drag ones feet05-04

Reduction of nitrate from groundwater: powder catalysts and catalytic membrane04-29

Adaptive speckle reduction of ultrasound images based on maximum likelihood estimation04-28

Effect of Reduction Temperature on Hydrofining Performance of Supported Molybdenum Phosphide Catalyst04-29

Nitrogen deposition and reduction of terrestrial biodiversity: Evidence from temperate grasslands04-29

Experiment and mechanism investigation on advanced reburning for NOx reduction: influence of CO and temperature04-27