RECTIFIED FLOW OF A ROTATING FLUID ALONG A VERTICAL SIDEWALL

The motion field resulting from an oscillatory, rotating flow parallel to a vertical wall and bounded from below by a horizontal plane along which there is no slip and from above by a horizontal frictionless li d is investigated numerically by using primitive equations. The model is barotropic and forced by oscillatory, spatially uniform, along-wall , and lateral pressure gradients. The pertinent parameters are the Ros sby, temporal Rossby, and Ekman numbers. By means of simulated particl e tracking, including a statistical analysis, and a consideration of m omentum balances, the physical mechanisms leading to flow rectificatio n are identified; i.e., the exchange of along-wall momentum of fluid p arcels communicating between the bottom Ekman layer, the vertical shea r layer, and the fluid interior. A rectified flow is generated along t he wall for all subinertial, inertial, and superinertial oscillation f requencies investigated. The direction of the rectified current is suc h that the sidewall is on the right, facing downstream, for a vertical ly upward or Northern Hemisphere rotation. The mean transports and wid ths of the rectified currents are determined as functions of the appro priate system parameters. The current width is much larger than the cl assical E1/4 Stewartson layer thickness. The numerical results are in good agreement with recent laboratory experiments.