Control of a Mach reflection-induced interaction using an array of vane-type vortex generators

An experimental investigation was conducted to control a Mach reflection (MR)-induced flow separation in a Mach 2.05 flow using a 18 shock generator (SG). The study was extended to four SG exit heights (g / w) of 0.87, 0.81, 0.725, and 0.66 primarily to study its effect on the extent of flow separation as well as on Mach stem height, with and without control. Two vane-type vortex generator configurations, namely the ramp vane (RV) with device heights , and 1.0 and the rectangular vane (RRV) with and 0.5, were studied for control. Each control device array was implemented 10 upstream of the separation location for no control. For stable MR interactions (i.e., ), the extent of separation and the reattachment shock strength are seen to decrease with increase in RV height (with device showing 17% reduction). However, for unstable MR condition (i.e., ), RV devices of and 1.0 become ineffective. The RRV2 device (), on the other hand, was found to be more effective in reducing the extent of separation in both the stable (31%) and unstable (24%) MR conditions. The effectiveness of each control device is also accompanied with an increase in height of the Mach stem. This is, however, not seen as a serious limitation since in such strong interactions it is more important to prevent or avert an intake unstart condition. The separation shock unsteadiness or the value, on the other hand, is seen to increase considerably with controls and seems to be almost independent for h/delta >= 0.5.