Reacting flow analysis in scramjet engine: effect of mass flow rate of fuel and flight velocity

Abstract The objective of the study is realizing the effect of fuel mass flow rate and flight speed on combustion in scramjet engine. DLR conical strut based scramjet combustor configuration was chosen and simulated the chemical reaction between the air and hydrogen fuel. A slot of size 40 mm × 0.295 mm provided at the center of the strut to injected hydrogen fuel from the rare side in to the downstream flow. ICEM CFD software is used for the generation of structured elements in computational domain for three dimensional flow analyses. Standard k-epsilon turbulence model and species transport equation is used in ANSYS fluent solver. The predicted temperature, velocity distribution along the axial length was compared with the experimental results and validated. The temperature distribution at different Mach numbers and mass flow rate reveals that the peak temperature increased with the flight speed and inlet fuel mass flow rate. The peak temperature noticed at the center of the combustor is around 3500 K at a flight speed of Mach 4. The predicted variation of temperature, pressure, velocity in the combustor and the flow structure for reacting flow facilitate good understanding of the combustion process in scramjet combustor.