Fluid Forces Acting on a Cube and a Strip Roughness Submerged in Open Channel Flow

Abstract

The flow induced forces acting on a cube and a strip roughness placed submerged on the bed in open channel flow were measured by using the three-component load cell. The flow around the cube were measured by using a laser Doppler anemometer (LDV) and a particle image velocimeter (PIV) and were simulated with a k-ε turbulence model. The drag and lift force coefficients of the cube and strip roughness in the open channel flow with free surface become large with increase of the ratio of cube height h and water depth d (h/d). The equivalent roughness k s for the strip roughness were also estimated by the measured drag forces acting on a strip roughness.