On the flow characteristics of minor-plane inclined elliptic jets.

Abstract

Flow characteristics derived from a particle-image velocimetry study on 30° and 60° minor-plane inclined elliptic jets are reported and compared to their major-plane inclined counterparts. Flow dynamics are clarified and found to be more sensitive towards the presence of inclined nozzle exits than the basic nozzle geometry and exact incline-plane used. Results show that the inclination of the inclined vortex roll-ups increases and decreases for 30° and 60° inclined nozzles respectively, similar to major-plane inclined elliptic jets. Based on available data, a critical incline-angle where the resultant inclined vortex roll-ups will neither increase nor decrease their inclinations has been estimated to be about 41° for minor-plane inclined jets. Flow quantities associated with cross-stream mixing characteristics are found to be dependent upon the exact incline-plane used. 60° minor-plane inclined jet attains the highest centerline turbulence levels and results demonstrate that flow events affecting radial velocity characteristics have significant influences upon the jet developments. Lastly, developments of mean streamwise and radial velocity components distributions indicated that minor-plane inclined elliptic jets incurred less flow asymmetry within the present measurement range than their major-plane inclined counterparts.