ADJUSTMENT OF A RURAL BOUNDARY LAYER TO A HEATED URBAN CANOPY

摘要

A nonlinear distributed drag model for urban canopy flow has been put together. The model successfully predicts the roughness length and the mean wind speed within arrays of regular obstacles. The mean wind in the canopy is shown to adjust on a lengthscale 3L_C which depends on obstacle density and drag coefficient. The model thus gives quantitative confirmation of linearised theory and shows promise for application in larger-scale NWP models. Further results on heated canopies and the effect of upstream boundary layer stability will be presented at the Symposium.