Improvement and validation of rapid prediction method for RBCC engine performance

Improvements for RBCC engine performance rapid prediction method have been done. Mass distribution functions for primary rocket exhaust and second fuel injection were reconsidered, with the key parameters identified by experiment results. Effects of cavities and fuel pylons on the cross section area of flow path were taken into account. Multi-positions of fuel injectors were considered also. The improved method was validated by direct-connected ground test and CFD results. The results show that the improvements are suitable for RBCC engine performance prediction, considering the complex flow path and multi-fuel injections. The thermal throat position can be predicted with a maximum ralative error of 13% compared with CFD results. The maximum ralative error of pressure integration along the flow path is 6.3% between prediction and experiment during ramjet mode. Compared with CFD results, the ralative error of thrust is 5.9% during ejector and ramjet mode, 7.7% during scramjet mode.