Abstract
This paper presents an experimental investigation of characteristics of the two kinds of wall jets issuing from a rectangular orifice with an aspect ratio of 5. One is the jet with a flat plate set along the long side of the exit (long side wall jet), and the other along the short side of the exit (short side wall jet). Measured results include mean velocities, intensities of streamwise turbulence and visualization of jet flow and the surface flow on the flat plate. The following results are obtained. The maximum mean velocities on the symmetric plane decay similarly as the free jet at the downstream region. In the case of the long side wall jet, the intermediate region between the potential core region and the downstream region appears longer than the others and the spread is strongly restricted near the wall. The saddlebacked mean velocity profiles are observed also for both of the wall jets. The visualizations of the flow by the smoke of dry-ice are consistent with the measured results, and the reattachments following the separation at the exit are confirmed on the plate by the oil-film method.
