AN IMPROVED METHOD OF SIMULATING AN ATMOSPHERIC BOUNDARY LAYER IN A WIND TUNNEL

An experimental assessment of various types of turbulence generators has led to the adoption of a system of elliptic wedge" generators and a castellated barrier to produce a simulated rough wall boundary layer. The characteristics of this simulated boundary layer have been measured and exhibit no significant spanwise variations. They are also sensibly constant over that area of a wind tunnel working section which would be occupied by a model. A working section length of between four and five boundary layer heights is required to produce the simulated flow. In all aspects considered the simulated boundary layer is comparable to a neutral atmospheric boundary layer. © 1969."