Wind-tunnel simulation of stably stratified atmospheric boundary layers

Results are presented of simulations of a stable boundary layer of moderate surface condition and zero overlying inversion strength. The layer depth is matched to model scale by artificially thickening the boundary layer by means of flow generators ('spires') at the working-section inlet. A non-uniform inlet temperature profile is essential in order to preclude the upper part of the layer retaining neutral conditions. The layer behaviour is sensitive to the prescribed form and care is needed in its specification. The results also show that the surface cooling should be started some distance downstream of the working-section inlet. The developed flow is closely horizontally homogeneous.