Pressure distribution on a low-rise building model subjected to a family of boundary layers

Abstract In natural environments, terrain roughness over a sizeable area is almost always in a random pattern. The roughness elements on the ground, e.g., trees and buildings, usually are not uniform in size, shape, or in the spacing between them. However, simulations conducted in the wind tunnel for such terrain conditions often simplify, if not completely overlook, the random nature of the problem. The randomness is typically replaced by a uniform roughness field in which the roughness elements are uniform in size, shape, and spacing. In fact, uniform roughness fields have become a standard tool in wind tunnel simulations. As a result, the prototype terrain condition is not modeled geometrically and the consequences of leaving out randomness in a simulation have not been examined thoroughly. To address this issue, several random roughness fields and one uniform roughness field were tested. Boundary layers generated by these roughness fields as well as the pressure distribution on a low-rise building model were recorded. Comparison of the resulting data showed significant differences between random roughness and uniform roughness simulations, even though all the boundary layer profiles fell within a single terrain roughness category.