摘要
This paper focused on the fundamental and applied research of turbulent flows encountered in the hypersonic flight of aerospace vehicles,which take place in the boundary layer and mixing layer.As to the plate boundary layer,LES approach has been used to simulate the flows over compression corners and incident shock waves,revealing that turbulent flows would significantly inhibit the boundary layer separation caused by shock wave-boundary layer interaction(SWBLI).The boundary layer transition over a circular cone has been analyzed through stability analysis and wind-tunnel test,by which the angle-of-attack effect in case of small angle of attack has been studied.Non-linear evolution process and secondary instability structure in the supersonic mixing layer(Mc=0.5) were initially figured out through the study of mixing layer,and knowledge of the flow control mechanism of the boundary layer and mixing enhancement mechanism of the mixing layer has been obtained through this research.Artificial boundary-layer transition technique based on subharmonic resonance has been proposed and applied to the flow control in a scramjet inlet,inhibiting the flow separation of the boundary layer while improving the inlet performance.To guarantee the mixing of kerosene and supersonic airflow in the scramjet combustor,the mixing enhancement method based on subharmonic resonance has been adopted and a concept of combustor with smooth wall and low internal drag has been proposed for ignition and stable combustion.Finally,future turbulence research and technological development of aerospace vehicles is predicted.
This paper focused on the fundamental and applied research of turbulent flows encountered in the hypersonic flight of aerospace vehicles, which take place in the boundary layer and mixing layer. As to the plate boundary layer, LES approach has been used to simulate the flows over compression corners and incident shock waves, revealing that turbulent flows would significantly inhibit the boundary layer separation caused by shock wave-boundary layer interaction （SWBLI）. The boundary layer transition over a circular cone has been analyzed through stability analysis and wind-tunnel test, by which the angle-of-attack effect in case of small angle of attack has been studied. Non-linear evolution process and secondary instability structure in the supersonic mixing layer （Mc=0.5） were initially figured out through the study of mixing layer, and knowledge of the flow control mechanism of the boundary layer and mixing enhancement mechanism of the mixing layer has been obtained through this research. Artificial boundary-layer transi- tion technique based on subharmonic resonance has been proposed and applied to the flow control in a scramjet inlet, inhibiting the flow separation of the boundary layer while improving the inlet performance. To guarantee the mixing of kerosene and supersonic airflow in the scramjet combustor, the mixing enhancement method based on subharmonic resonance has been adopted and a concept of combustor with smooth wall and low internal drag has been proposed for ignition and stable combustion. Finally, future turbulence research and technological development of aerospace ve- hicles is predicted.
