环包式并联可调组合喷管设计与性能研究

Size constraints in airframe/propulsion integrated design and high-performance requirements across a wide flight trajectory are addressed. A nozzle design method with controllable expansion rate in the initial expansion section is introduced by combining the Foelsch design method with maximum thrust theory. The contour design method for the dualthroat nozzle in an axisymmetric wrap-around combined cycle engine is further developed. Design principles of the thrust nozzle and dual-throat nozzle are outlined. Performance impacts of different benchmark nozzles on the combined nozzle are compared. Aerodynamic performance of the nozzle throughout the flight trajectory is evaluated. It is demonstrated that， compared to schemes using maximum thrust nozzles as benchmark nozzles， the proposed benchmark nozzle shortens combined nozzle length and increases thrust coefficient. Combustion chamber flow matching over a wide flight regime is enabled by an external annular nozzle translation scheme， while high axial thrust coefficients are maintained by the proposed surface design in both individual and coupled operational modes.