Optimizing combustion performance in a solid rocket scramjet engine

To enhance combustion efficiency of a boron-based propellant solid rocket scramjet (SRS) engine, this study attempted a new organization scheme combining cavity and pneumatic slope. To optimize the proposed system, a series of numerical simulations were performed, and through orthogonal design and single factor analysis, the key factors were determined. The developed two-phase flow simulation has been verified by the full-scale ground test, given an error within 10%. The results show that for both combustion efficiency and total pressure recovery, the influence of gas injection mode is much greater than the ratio of the length to depth of the concave cavity as well as the cavity depth. And the combustion performance has proved to be optimized via the enlarged low speed area near the cavity and the strengthened particles reflux.