Simulations of scramjet starting and establishment time in an expansion tunnel

摘要: A "nose to tail" numerical simulation is used demonstrate that steady flow can be achieved through a complete scramjet model in an expansion tunnel. For this study, was undertaken for single condition of interest from the X2 tunnel, using un-fueled combustor. The results facility matched reasonably well with experimental measurements and simulated exit tunnel then as transient inflow boundary into simulation. simulations showed that, studied variables, inlet started relatively short period. Further duct, unsteady resulted some movement wave pattern over time. To obtain estimate establishment time somewhat insensitive small movements pattern, new variable constructed by integrating normalized pressure distribution lengths duct. This measure show would reach quasi-steady after 350 μs have test period 200 μs.