Abstract:The TBCC inlet plays an important role in the performance enhancement of wide-operating vehicles. In this paper, an unsteady simulation of the dual-channel co-operating process of an externally-parallel TBCC inlet in the Ma3.5 state is carried out. Firstly, with the gradual increase of the turbine channel backpressure, the terminal shock train keeps moving upstream, and it is found that during the increase of the turbine channel backpressure ratio from 30 to 49.6, the bleeding flow can play a role in stabilizing the terminal shock train in the turbine channel regulation process, and the bleeding flow rate increases from 2.8% to 4.39%, so that the position of the terminal shock train moves relatively very tiny. When the terminal shock train expels out of the channel and the turbine channel falls into unstart. The unstart of the turbine inlet channel forces the separation to extend significantly into the forebody, thus inducing the unstart of the ramjet channel. In contrast, the throttling process of the ramjet inlet has relatively little effect on the flow field structure of the turbine channel, and the wall pressure distribution indicates that the pressure fluctuations of the turbine inlet keeps in the range of 0.2 to 0.4 P0, accompanied by high-frequency oscillations. Finally, the results suggest that the leakage at the junction of the manifold and the inlet body does not contribute to the improvement of the aerodynamic performance of any of the channels, and therefore should be minimized.
