Drag Reduction by Boundary-Layer Combustion: Influence from Disturbances Typical of Cross-Stream Fuel-Injection

摘要

These experiments show that the measured levels of skin-friction reduction due to boundary-layer combustion are. similar to those measured in the experiments without vortex generators. This is a clear demonstration that flow disturbances similar to those from cross-stream fuel injection in the inlet and isolator of a scramjet engine do not affect the drag reduction potential of boundary-layer combustion. A positive implication of these results is the possibility of using cross-stream fuel injection in the inlet in conjunction with tangential fuel injection at the start of the combustor. Using a combined fuel-injection scheme of this configuration in a scramjet engine may provide the potential to obtain not only the benefits of thrust addition and viscous drag reduction from boundary-layer combustion but also those of thrust addition from mainstream combustion.