MECHANICALLY INDUCED UNSTEADY COMPRESSIBLE EKMAN LAYER

The compressibility effect on a mechanically induced unsteady Ekman layer has been investigated by using the boundary layer theory. The analytic solution is obtained for the case in which the Prandtl number is equal to unity. It is found that the period of the inertial oscillations expressed by the Fresnel integral S(2σ2τ) becomes short as the compressibility is increased, and the unsteady Ekman layer of a compressible fluid (σ>1) reaches the steady state faster than that of an incompressible fluid (σ=1). Here a is the compressibility parameter and time t is nondimensionalized by an inverse of the angular velocity Ω-1. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.