構造粗さを有する多孔体界面乱流の平均速度スケーリング

抄録

Systematic PIV measurements of turbulent channel flows over rib-roughened porous media are conducted to find universal correlations for the combined effects of the roughness and the wall-permeability on turbulence. Square porous ribs whose height k is 10% of the channel height are set at regular intervals, of w/k=1,3,7,9,19. Three kinds of porous media applied have the same porosities, 0.95, but different mean pore diameters. By fitting the mean velocity profiles to the logarithmic law, discussions of the log-law parameters are conducted. It is then confirmed that the zero-plane displacement has a linear relationship with the roughness scale and that the newly determined effective displacement well correlates to the mean pore diameter.