Effects of flight dynamic pressure on plume temperature distribution and heat release characteristic in the kerosene-fueled scramjet.

This article experimentally investigates the effects of flight dynamic pressure on plume temperature distribution and heat release characteristics in kerosene-fueled scramjets. Tests were conducted using direct-connect scramjet models at two flight dynamic pressures, 41 kPa and 85 kPa, with measurements of plume radiation intensity, temperature distribution, and wall pressure obtained via multispectral imaging and pressure sensors. Results indicate that higher flight dynamic pressure (85 kPa) enhances plume radiation intensity, combustion stability, and heat release compared to lower pressure (41 kPa), with fuel injection volume having a more pronounced stabilizing effect at higher pressures. The study also identifies a transition in combustion mode from cavity-based to shear-layer stable combustion as flight dynamic pressure decreases, affecting flame location and wall pressure distribution. These findings contribute to understanding scramjet combustion behavior under varying flight conditions relevant to hypersonic propulsion research.