Research On Flow Field Control Technology Of Three-Dimensional Inward Turning Inlet

The flow field parameters of the typical three-dimensional inward turning inlet are unevenly distributed and self-starting is difficult.In order to improve the flow-field parameters distribution and aerodynamic performance of the inward turning inlet,In this paper,the numerical simulation method is used to study the flow characteristics of the inward turning inlet based on the profile flow field control.The key aerodynamic influence factors and design parameters of the inward turning are given,and the corresponding influence laws are obtained.Firstly,the main flow characteristics of the typical inward turning inlet are analyzed.The result shows that the flow vortex induced by the shock wave of cowl and the boundary layer of the sidewall is the main influencing factor of the flow characteristics of the inlet,which results in uneven distribution of the flow field parameters and a relatively large low velocity and low pressure area near the compression surface.The area affects the aerodynamic performance of the inlet.Then,Based on the above research,the research on the flow control of the inward turning inlet type surface is carried out.The key design parameters of the inlet control surface and the range of parameter values are obtained,and the corresponding influence law is obtained.The research shows that the offset and centerline are the key design parameters of the control profile.Within the scope of the study,reasonable setting of the above parameters can improve the flow field parameters distribution characteristics of the inlet and improve the performance of the inlet.Thirdly,the influence mechanism of key parameters of profile flow control on the inlet is analyzed.The inward turning inlet profile flow control scheme proposed in this paper affects the development and spatial distribution of the boundary layer and improves the uniformity of the circumferential distribution of the boundary layer.The analysis shows that the profile flow field control scheme can reduce the shock intensity of the cowl?reconstruct the pressure distribution of the shock interference zone of cowl,reduce the lateral pressure gradient of the interference zone,weaken the flow vortex intensity,and control the flow vortex generation?development and spatial distribution to improve the uniformity of the flow field parameters distribution.Finally,based on the above research,a better design plan of inward turning inlet based on profile flow control is given.