高レイノルズ数領域における円柱の抵抗と発生うず列 : 表面粗さの影響

概要

論文の詳細を見る
Discussions are made on the effect of surface roughness on the drag coefficient and Strouhal numbers 5×10^5≦Re≦10^7. There is the maximum value of surface roughness which does not effect the drag coefficient and Strouhal number in the subcritical and transitional range and at the critical point. This maximum value is determined as (K_s/d)_<crit>=5×10^<-4>. For a larger relative surface roughness value, there are some functional relations between the relative surface roughness (K_s/d) and the minimum drag coefficient and the Reynolds number which corresponds to C_<D min>. In the transcritical Reynolds number range, the drag coefficient depends on the relative surface roughness. It increases with an increase in the relative surface roughness. There arise vortex streets in the wake of a cylinder which satisfy the Bearman's condition, i. e. St*=0.181 in the subcritical and transcritical Reynolds number ranges.
社団法人日本機械学会の論文
1989-09-25