Effect of Merging Angle on Turbulent Mixing Layers

Experimental investigations have been conducted on the two types of mixing layer s produced from two streams merging at 0 and 20. Each type of mixing lauers was produced with velocity ratios of 0.7, 0.8 and 0.9, and mecsuremen is Wt IF done at six streamwise locations . The boundary layers were untripped and the initial boundary layers were turbulent in all the cases. The results show that the splitter wake play a dominant role in the development of the mixing layers. Both types of mixing lau ers attain ed se lj-similaTity fo r ve loci ty ratios of 0. 7 an d 0.8. but failed f or 0.9 within the measurement domain. With the increasing velocity ratio. development distance was increased and growth. was decreased for both types of mixing layers, but the mixing lasjers with non-zero merging angles have higher growth than the zero angle one for the same velocity ratio , Both types of mixing layers were f ound to spread more and more into the high speed region with the increasing velocity ratio.