Numerical Simulation of UVA Ramjet/Scramjet Hypersonic Engine with Hydrogen-Air Combustion Using Wind-US

The internal flowpath of University of Virginia\u27s Mach 5, direct-connect, dual-mode scramjet engine was simulated using Wind-US, a density-based Reynolds-Averaged Navier-Stokes flow solver. Detailed flowfield simulation results are directly compared to experimental data to evaluate the accuracy of the numerical model and to provide insight into the flowfield behavior. Four hydrogen-air reaction mechanisms were initially assessed using the Burrows-Kurkov case. An Evans-Schexnayder, 7-specie, 8-reaction set with third body efficiencies was then selected for the scramjet simulations. The scramjet simulations included one fuel-off case and two reacting cases with different equivalence ratios, all with clean, non-vitiated air supply. The strong sensitivity of the simulation results to the choice of turbulent Schmidt number is demonstrated. For low equivalence ratio, excellent agreement with experimental data is achieved. For high equivalence ratio, the results agree with that of experiment, however, this case shows large numerical and combustion instabilities