高超声速冲压推进中的斜激波诱导湍流燃烧机理研究

Air-breathing hypersonic propulsion technology is one of the important research directions in aerospace science and technology, and plays the strategic role in the development of Chinese aeronautical and aerospace propulsion technology. In the system of air-breathing hypersonic propulsion, the fundamental scientific problems have been clarified, and engineering application of Scramjet is developed by overwhelming the critical technology issues. However, for the hypersonic propulsion with flight Ma around 10, there are not universal opinions on how to organize the combustion. Theoretically, both Scramjet and oblique detonation propulsion are possible and each has its special advantages, although both of them can be viewed as the turbulent combustion induced by the oblique shock. Now it is still lack of systematic evaluation on two propulsion technologies, embarrassing the future engineering research. This proposal will study the turbulent combustion with advantaged numerical algorithm, as well as the verification experiments based on the instruments of hypersonic ground tests. The turbulent combustion mechanism derived from shock/heat release coupling in hypersonic engines will be studied, and effects of flight Ma on shock and flame structure will be analyzed. Then, targeting flight Ma 7~10, the performance evaluation and optimization method of Scramjet and oblique detonation engine will be built up, providing the scientific fundaments for the engine-type choice of high Ma hypersonic propulsion technology.

高超声速吸气式推进技术是空天科技发展的重要方向，对我国航空宇航动力技术发展具有战略意义。高超声速吸气式动力系统中，马赫数7以下的基础科学问题已经基本明确，正在通过技术攻关逐渐推进超燃冲压的工程应用。然而对马赫数10量级的高马赫数高超声速推进，采用何种燃烧组织形式，学术界和工程界并没有一致的看法。从原理上，超燃冲压推进与斜爆轰推进均可应用，两者同为斜激波诱导的湍流燃烧，技术上各有优势。目前对两种燃烧推进方案的系统评估尚未开展，导致进一步的工程研究缺乏科学基础。本项目拟利用数值模拟研究冲压推进系统中斜激波与化学反应耦合的湍流燃烧机理，并结合高超地面模拟方设备开展验证试验，分析马赫数影响激波与火焰结构的作用规律。以此为基础，建立马赫数7~10区间内超燃冲压与斜爆轰推进的性能分析与优化方法，为高马赫数高超声速推进技术路线的选择提供科学依据。

在本项目支持下，研究团队对斜激波与化学反应耦合下的湍流燃烧机理开展了研究，掌握了马赫数影响激波与火焰结构的作用规律，厘清了燃料性质对斜爆轰的影响。上述结果形成了完整、系统的研究成果，为斜爆轰从基础研究走向应用建立了桥梁。 发展了基于多种CFD算法和化学反应模型的模拟程序并进行了验证，进而利用超算平台开展了大规模、高精度的模拟，获得的成果揭示了斜爆轰波的机理，支撑了正在开展的工程应用研究。发表SCI期刊论文15篇，国内期刊论文3篇，包括J. Fluid Mech.1篇，Phys. Fluids 2篇，Combust. Flame 3篇，Proc. Combust. Inst. 1篇，AIAA J. 2篇，Fuel 2篇。上述文章也被国内外同行广泛引用，产生了一定的国际影响。培养毕业博士生多人，晋升正、副高级职称3人次，项目负责人获得国家自然科学基金委优青项目资助。