Effects of strut swept angle on the drag of scramjet

Swept angle is one of the most important geometric parameters of the strut in scramjet. The change in swept angle will make the geometric shape of the strut different and lead to distinct performances. Computational fluid dynamics method has been used in this study to obtain the cold-state flow field of scramjet model with struts of different swept angles at freestream Mach numbers 5 and 6. The results show that the effect of strut swept angle (from 0 degrees to 60 degrees) on the flow-field structure, total pressure losses, and drag coefficients is less. However, in the cases when strut swept angle is larger than 60 degrees, the shock waves have been weakened significantly and so are the total pressure losses and the strut drag coefficients. In addition, the drag coefficients of all the struts are overall very small because of the small wedge angle of the leading edge. Also, the drag coefficient on the struts reduces when Mach number of freestream increases.