双模态超燃冲压发动机对隔离段性能的需求分析

为研究双模态超燃冲压发动机的燃烧室一隔离段共同工作过程，分析不同模态下燃烧室对隔离段的性能需求，在基于集总参数方程的超燃冲压发动机性能计算模型的基础上，提出计算燃烧室一隔离段流量平衡的临界能量法，并编制相应的计算程序，实现双模态超燃冲压发动机各种模态的隔离段和燃烧室的流量平衡计算，计算在不同的模态下隔离段和燃烧室的一维流动参数，进而获得隔离段的性能需求，计算飞行马赫数4．0到7．0时的临近堵塞边界的最大供油量与隔离段最大激波链长度。结果表明：临界能量法正确有效，能完成燃烧室一隔离段流量匹配计算；高飞行马赫数下的堵塞模态的隔离段激波链长度较长，应作为隔离段的工程设计中所参考的重要因素。

Analysis of isolator performance requirement for dual-mode Scramjet

For studying combustor-isolator matching of dual-mode Scramjet and analyzing the performance requirement of isolator in different mode, based on lumped parameter equations for performance computation of scramjet put forward by our team, critical energy method was put forward for computation of mass flow balance between isolator and combustor, the computation model of Scramjet was built, and the corresponding computer program was developed, the dual-mode Scramjet performance and mass flow balance in different mode were computed and analyzed, one dimension flow parameters of isolator and combustor were gained and study in different mode, and the isolator performance requirement of Scramjet were found. The maximum fuel mass flow and isolator separate length near choking margin was computed when flight Mach number Ma₀=4.0~7.0. It was shown from the computation results that: critical energy method was correct and effective and it could be used for computation of mass flow balance between isolator and combustor, the isolator separating length is much longer when the Scramjet operates in choking mode at high flight Mach number, and it should be took into basic consideration for engineering design.