Microvortex Generator Controlled Shock-Boundary Layer Interactions in Hypersonic Intake

摘要

The occurrence of shock and boundary layer interactions (SBLIs) in aircraft-engine intakes often results in poor total pressure recovery, a degraded boundary layer, and, in worst cases, flow separation. Hence, the SBLIs must be controlled to reduce/eliminate the losses. In this study, the efficacy of conventional microvortex generators (MVGs), deployed before and at the interaction region of a Mach 5.7 mixed-compression intake, has been investigated experimentally. Specifically, an array of MVGs, placed in the spanwise direction, was found to be useful in reducing the extent of the interactions. The height of the MVGs was varied as 0.5, 0.7, and 1 mm. Both quantitative and qualitative investigations have been carried out by measuring the static pressure distribution over the surface of the ramp and visualizing the SBLI phenomena at various time instants during the test run using the time-resolved Schlieren technique. The MVGs with a height of 1.0 mm, deployed at the interaction region, appeared to be quite effective in reducing the wall static pressure, with a maximum of a 13.57% reduction at the downstream proximal location. In addition, the Schlieren images show a decrease in the separation bubble size in all the intakes controlled with MVGs; a maximum reduction of 31.25% in the bubble length is achieved with 0.7 mm MVGs, which is deployed upstream of the interaction point.