Apparent shear stress in symmetric-straight compound-channel flows

Apparent shear stress, which is presented in forms of roughness ratio, width ratio and depth ratio between main channel and flood plain, is quite important in the compound channel flows with the behaviors of momentum transfer on control works for both soil material and contaminate transports. The analytical solutions of apparent shear stress for symmetric-straight compound channel flows both in main channel and flood plain are derived and compared with the results of experimental and numerical outputs. The acceptable tendencies and agreements are presented. The significances of the ratios on roughness, width and depth are discussed for the characteristics of apparent shear stress.