Part-depth wind tunnel simulations of the atmospheric boundary layer

Wind tunnel tests on wind loading on structures require the simulation of the atmospheric boundary layer. Several methods have been proposed since 1960s in order to reproduce the atmospheric flow. It is accepted that the best atmospheric boundary layer simulation is obtained with rough surface on the floor, although simulation scales reached by this method are too small for usual applications in structural aerodynamics. Following on from that techniques to accelerate the boundary layer growth, known as roughness, barrier and mixing-device method were developed. Two techniques of this type, both widely used, were developed by Counihan and Standen and they originally were considered to be for full-depth simulations. In this paper, the results of four part-depth simulations using modified Counihan and Standen simulation hardwares are presented. During these tests mean velocity profiles, turbulence intensities, power spectra and integral scales were measured. The comparison of the suburban simulations with atmospheric data showed an acceptable agreement. It is shown that when comparing with atmospheric data it is preferable to use comparative procedures which do not use the boundary layer thickness as a scaling factor.