S054012 2次元粗面に付加した微細な縦溝が乱流境界層の相似則に及ぼす影響([S05401]噴流,後流,およびはく離流れの基礎と応用:最前線(1))

Abstract

Measurements of mean velocity throughout a layer and surface pressure around a rough surface have been performed to investigate the effect on three-dimensionality of a roughness element due to micro-grooves. All experiments were made at a unitary Reynolds number of 6.24 x 105 (m-1) and in zero pressure gradient. The representative scale normalized with an averaged roughness height has little effect of the three-dimensionality of the rough surface. The pressure drag coefficient has almost same value with that of a two dimensional rough surface. Roughness function can be represented as a function of the Reynolds number based on the representative roughness scale, and the intercept term of the function depends on the three-dimensionality of the rough surface.