Velocity Profile of a Boundary Jet in a Rotating Fluid

A laminar boundary jet adjacent to a vertical sidewall of a rotating circular cylinder was studied experimentally. The boundary jet was produced by differential rotation of a ring-shaped plate along the periphery of the top surface of the working fluid. The velocity field of the resulting boundary jet was observed by a pH-indiator method with special interest in the case when the with of the driving ring was O (E^1/4 (Eis the Ekman number). It was demonstrated that the azimuthal velocity has an appreciable vertical shear and that the vertical velocity in the boundary jet is of order £114. The vertically averaged azimuthal velocity profile was compared with an empirical formula which is a modified version of the theoretical solution given by Kimura (1976)