粗面乱流境界層における LEBU の制御に関する研究

抄録

The effectiveness of LEBU for drag reduction in rough wall turbulent boundary layers has been examined experimentally. LEBU was located at two different heights, 0.4δ and 0.8δ and local wall shear stress was measured by drag balance device. The mean velocity and Reynolds shear stress profiles were measured by constant temperature anemometers. It is confirmed that LEBU is effective for drag reduction in rough wall boundary layers. The reduction rate of local skin friction coefficient in the rough wall flow is larger than that over smooth surface. Reynolds shear stress measurements state that LEBU reduces momentum transfer due to turbulent motion produced by interaction between boundary layer flow and roughness elements.