A wind-tunnel facility for simulating mountain and heated-island gravity waves

A wind tunnel was constructed to study mountain lee-wave phenomena and heated-island effects. The present wind tunnel appears to have several advantages over a towing tank facility for modeling atmospheric gravity-wave phenomena, i.e., non-uniform approach flows, stationary measuring conditions, variation of boundary temperature condition in the longitudinal direction, and no slip at the wall. Simple design criteria and characteristics of the present wind tunnel are discussed. A numerical program was utilized to explain peculiar standing-wave disturbances in the wind-tunnel test section. The above disturbances seemed unavoidable under the chosen mechanical constants. Nevertheless, a practical solution was found by extending the tunnel length.Postdoctoral Fellow, Princeton University, New Jersey, U.S.A.Associate Professor, Fluid Mechanics Program, Colorado State University, Fort Collins, U.S.A.