An experimental study of upward jet impingement is conducted with the visualization of the laminar vortices generated by the circular jet when this jet impinges normal to a impinging plate.
The characteristics of the vortex with the radial wall jet front have been observed experimentally using kerosene in jet to visualize the flow in the vortices as well as near the impinging plate. And the investigation was undertaken to explore the possibility of simulating thermally buoyant gases with a helium-Nitrogen mixture and thermal pure nitrogen jet. Parameters such as the volume flow rate of the nitrogen and helium, initial helium concentration were varied over wide ranges.
This study shows that the radial wall jet generates very large, distinct and rapidly rotating vortex - primary vortex. And there are 3 dimensional motion when the secondary vortices interacts with the primary vortex. The primary vortex which form the front of radial wall jet is translated by merging with the secondary vortices which are generated at the boundary layer unsteady separation point.
