Application of Stereoscopic Particle Image Velocimetry to a Dual-Mode Scramjet

A stereoscopic particle image velocimetry measurement technique has been developed for application to a dual-mode scramjet combustor. The dual-mode scramjet combustor facility is briefly discussed, followed by presentation of the equipment used for the stereoscopic particle image velocimetry measurements. An iterative design procedure was used to identify the optimal configuration of the stereoscopic particle image velocimetry system for application to the dual-mode scramjet combustor, and this optimal configuration is presented. Experiments were conducted using the configuration and produced three-component velocity measurements at a cross plane of the dual-mode scramjet combustor for the case of fuel air mixing and for the case of fuel air combustion. Results are presented and compared for the purpose of gaining better understanding of the complicated dual-mode scramjet flowfield. The stereoscopic particle image velocimetry measurements quantified the three-component velocity field of the dual-mode scramjet combustor and, for the first time, characterized the size and structure of the ramp-induced vortices for fuel air mixing and fuel air combustion cases. Significant differences were observed in the velocity field of the fuel air combustion case. Specifically, for the fuel air combustion case, the fuel plume was larger and the ramp-induced vortices were larger and less well-defined than in the fuel air mixing case.