Jae-Hyun Han and Jung-Soo Kim
International Journal of Railway, vol. 4, no. 3, pp.74-79, 2011

Abstract : Recent years have witnessed speed up of moving vehicles such as high-speed of trains. Increase in speed entails concomitant increase in turbulent air flow which contributes toward increased aerodynamic noise. The proposed method for aerodynamic noise reduction is based on a biomimetic design of owl feather. The five morphological parameters of the owl feather are extracted from close observation, and simulation cases are constructed by applying design of experiments methodology. Swirling strength for each case is obtained through steady-state CFD analysis, and key morphological parameters that affect the turbulence are identified. Large eddy simulations (LES) are then performed on selected cases to predict the air turbulence. Different cases show varying vortex distributions which are expected to lead to varying aerodynamic noise levels.

Keyword : Aerodynamic noise, Biomimetics, Computational fluid dynamics, Design methodology, Owl feather, Turbulence,