Investigation on the shock interactions between an incident shock and a plate with V-shaped blunt leading edge

The cowl lip of a hypersonic inward-turning inlet is a critical region due to the complicated three dimensional shock interactions. To reveal these shock interactions and the inherent mechanisms, a simplified model of a plate with a V-shaped blunt leading edge was proposed to simulate the main characteristics of the cowl lip flow. Experimental observations in a shock tunnel in conjunction with numerical simulations were conducted to examine variations of the relative position of a wedge-induced forebody shock and the cowl lip. The results show that the stand-off distance of the bow shock in front of the stagnation point is large (compared with the bow shock of a cylinder with the same radius), followed by a wide subsonic flow region behind the bow shock. When the oblique shock impinges on the near normal part of the bow shock, Edney type Ⅳ a shock interaction occurs. On this occasion, the interaction between the incident shock and the bow shock is coupled with the shock interactions induced by the three dimensional flow over the V-shaped blunt leading edge, causing several regions of supersonic jet. When the oblique shock impinges on the subsonic region near the sonic point of the bow shock, a type of shock interaction that is different from the classification of Edney type Ⅲ is shown. When the oblique shock intersects with the bow shock at the supersonic region, the shock interaction structures are similar to the shock structures of Edney type Ⅱ and type Ⅵ. More attentions should be paid to the shock interaction problem of the V-shaped blunt leading edge cowl in the design of an inward-turning inlet.