粗面上に発達する乱流境界層の数値シミュレーション (流れ方向に粗度が変化する場合)

Numerical simulations of turbulent boundary layer over a step change in surface roughness are performed using a refined k-εturbulence model. The model derives from the Navier Stokes equations by the time space averaging in consideration of the drag effect by roughness elements and volume change of roughness elements. Comparison between calculations and experimental data shows the applicability of the numerical method presended in this paper. Finally the variations of the flow over a step change in surface roughness are examined using the calculated values.