Drag coefficient and upstream influence in three-dimensional stratified flow of finite depth

摘要: A numerical study of the three-dimensional stratified flow past a vertical square flat plate in channel finite depth is described. Particular attention paid to anomalous dependence drag coefficient CD on parameter K( = ND/-πU), where N Brunt-Vaisala frequency, D half and U upstream velocity. It shown that generally increases with K, while it decreases locally at integral values K. Time development columnar disturbance corresponding variation reveals periodic time for K > 1 comes from successive radiation disturbances first internal wave mode. Although propagation speed consistent prediction linear theory, its time-dependent structure different weakly nonlinear theory as has been by laboratory experiments.