Effect of wedge strut angle on shock wave generation and supersonic air-fuel interaction

This research work mainly focusing on the result of shock wave strike on shear mixing layer for different angles of wedge strut fuel injector. This study examines the shock waves produced by a wedge-shaped strut, utilizing different divergence angles to alter the shock angle. The initial compression wave is created at the leading edge of wedge strut, while a second wave originates at the strut’s end. These shock waves interact and converge at a specific point within the shear mixing layer, enhancing hydrogen-air mixing. The study begins with a standard DLR (German Aerospace Centre) scramjet combustor model equipped with a strut featuring a 12-degree divergence angle. This angle is then varied to 4, 8, and 16° to analyse trends in oblique compression wave formation and their result on the shear dispersion layer. Numerical simulations are executed using ANSYS Fluent and the Reynolds-Averaged Navier-Stokes (RANS) equations to demonstrate the influence of altering strut angle on shock wave formation. For an 8-degree strut, the shock waves converge at a point 136 mm downstream from the air inlet, substantially intensifying air-fuel mixing and improving combustion efficiency. The reaction rate increases by 12% with the 8-degree strut compared to the original 12-degree design. This improvement leads to a 7% higher combustion efficiency relative to the standard DLR scramjet combustor.