Numerical Studies on the Performance of Scramjet Combustor with Alternating Wedge-Shaped Strut Injector

Numerical analysis of the supersonic combustion and flow structure through a scramjet engine at Mach 7 with alternating wedge fuel injection and with three angle of attack (alpha = -3 degrees, alpha = 0 degrees, alpha = 3 degrees) have been studied in the present research article. The configuration used here is slight modification of the Rabadan et al. scramjet model. Steady two dimensional (2D) Reynolds-averaged NavierStokes (RANS) simulation and Shear stress transport (SST) based on k-omega turbulent model is used to predict the shock structure and combustion phenomenon inside the scramjet combustor. All the simulations are done by using Ansys 14-Fluent code. The combustion model used here is the combination of eddy dissipation and finite rate chemistry models since this model avoids Arrhenius calculations in which reaction rates are controlled by turbulence. Present results show that the geometry with negative angle of attack (alpha = -3 degrees) have lowest ignition delay and it improves the performance of scramjet combustor as compared to geometry with alpha = 0 degrees, alpha = 3 degrees. The combustion phenomena and efficiency is also found to be stronger and highest in case of alpha = -3 degrees.