Abstract When a turbulent flow reaches a sudden expansion as in the case of a backward-facing step (BFS), a turbulent separated shear layer originates from the trailing edge. The reattachment location of this shear layer varies in time and space, causing high dynamic loads on the reattachment surface. This is an inherent problem on some of today’s cryogenic space launchers, where the main engine’s nozzle suffers from high buffeting loads during the transonic phase of the ascent, due to a turbulent reattaching shear layer, especially originating from a geometric discontinuity, similar to a BFS. For this reason the aim of the current research focuses on stabilizing and reducing the reattachment length of the separated shear layer on a BFS in transonic flow by the means of passive flow control devices. Several streamwise vortex generators were examined in the Trisonic Wind Tunnel Munich (TWM) with particle image velocimetry (PIV). The investigations were conducted on a 2D model at Mach 0.8 and a Reynolds number of with respect to the step height (h). The results show that streamwise vortex generators have a tremendous effect on reducing the size of the recirculation region, reducing the reattachment location by 75 % or more, when compared to the reattachment location of a BFS wake.
Control of the Reattachment Length of a Transonic 2D Backward-Facing Step Flow
Proceedings of the 5th International Conference on Jets, Wakes and Separated Flows (ICJWSF2015) ; 3 ; 241-248
Springer Proceedings in Physics ; 185 , 3
2016-01-01
8 pages
Article/Chapter (Book)
Electronic Resource
English
Control of the Reattachment Length of a Transonic 2D Backward-Facing Step Flow
British Library Conference Proceedings | 2016
|Transonic flow past a backward-facing step
AIAA | 1977
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