RBCC变结构燃烧室几何喉道适用范围研究
Investigation on the Applicable Scope of Geometrical Throat in RBCC Variable Structure Combustion Chamber

变结构燃烧室几何喉道能够提高冲压发动机亚燃模态性能，旨在研究宽马赫数范围RBCC燃烧室几何喉道的适用范围和作用机理。首先采用气流推力分析方法研究燃烧室气动参数变化规律，结果表明，在3 000 K燃烧室极限温度范围内，燃烧室几何喉道适用范围可以拓展至飞行马赫数Ma=7.0。随后在Ma=6.0变结构燃烧室构型基础上，进行了Ma=6.0、6.5以及7.0条件下发动机全流道一体化三维数值计算，对燃烧流场结果对比分析发现：几何喉道对RBCC高飞行马赫数条件下的燃烧释热有积极作用，并具有较好的发动机性能，表明保持Ma=6.0几何喉道仍能对Ma=6.5、Ma=7.0来流起到改善燃烧品质提高发动机性能的作用，燃烧室几何喉道在Ma ≤ 7.0范围内有效。最后，通过模拟Ma=6.0来流地面直连实验研究表明：采用几何喉道方式能够保证燃烧室内燃料的高效稳定燃烧。
The geometrical throat of variable structure combustion chamber can improve the performance of ramjet engine. For purpose of expand the range of application of geometrical throat of variable structure RBCC engine and study the performance in high flight Mach number, stream thrust analysis method was firstly adopted. It shown that combustor geometrical throat can be utilized up to flight Mach number Ma=7.0 with the limiting temperature of 3 000 K. Based on the configuration of Ma=6.0 variable combustion chamber, three-dimensional numerical simulation of the engine flow path at Ma=6.0, 6.5 and 7.0 was carried out to comparative analyze the flow field details. The results show:the geometrical throat has a positive effect of the heat release to combustion of RBCC under conditions of high flight Mach number, and has a better engine performance, validated the geometrical throat can be applied to the Mach number Ma ≤ 7.0. Finally, the results of ground direct-connect experiment in the simulated flight Mach number Ma=6.0 condition show that the geometrical throat can ensure the efficient and stable combustion of the combustion chamber