| Abstract: | A one-dimensional theoretical model was adopted in this paper to describe and analyze the flow in an expanding RBCC(rocket based combined cycle)duct.It can be concluded that the expanding angle,heating amount and distribution of heating play crucial roles on the thermal choking.They mainly influence the acceleration of flow,the position of choking throat and the total pressure loss.In order to fulfill the transition of subsonic flow to supersonic flow in the expanding RBCC duct,the heating amount has to change from a bigger value to a smaller one along the duct.When the thermal choking occurs in the RBCC duct,the moderate expanding angle,proper heating amount and distribution of heating are necessary for the best performance of RBCC combustor.Adopting the RBCC duct with smaller expanding angles anterior and bigger expanding angles posterior has positive effects on the thermal choking and flexibility of selecting heating method,and can restrain the negative effect of the combustion on the inlet also. |
