Parametric Analysis of Pylon-Aided Fuel Injection in Scramjet Engines

Abstract

The current study investigates means to increase the efficiency of fuel-air mixing into supersonic flow upstream of a flame holding cavity. Previous work has shown much promise in increasing the penetration and mixing of a fuel-air mixture into the freestream by injecting fuel behind small triangular pylons. The current paper examines 21 triangular pylons of varying widths, heights, and lengths with a computational fluid dynamics (CFD) performance analysis. Increasing the height of the pylons increased the penetration, flammable fuel plume area, and floor gap. Variations in pylon length had no discernible impact on the fuel-air mixing metrics. Aerodynamic loses were minimal for all pylon configurations and did not correlate to the absolute size of the pylons tested.