Abstract The liquid oxygen/methane engine is a desirable power for reusable launch vehicle. It is generally believed that the efficiency of the liquid oxygen/methane engine is mainly influenced by the injection conditions of the thrust chamber. However, due to the complexity of combustion experiments, the exact influence of specific injectors on the combustion performance is difficult to acquire. By analyzing a typical sub-scale thrust chamber, this paper presents a three-dimensional numerical model to evaluate the effects of three major injector parameters, i.e. the thickness of liquid oxygen post, the number of injectors and the type of injectors, on liquid oxygen/methane engine combustion performance. The results of the simulation are consistent with existing experimental data in the chamber pressure, combustion stability, as well as wall heat flux. This paper's results have shown that the larger liquid oxygen post thickness and swirl coaxial injector can significantly reduce the heat flux while influence of the injector number is relatively small. Furthermore, the decrement of the liquid oxygen post thickness can improve the combustion efficiency. And the less injectors lead to the more stable combustion. The presented simulation model gives a reliable and cost-effective way to analyze specific injector parameters and provides new principles for future liquid oxygen/methane engine design.

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同轴喷射器参数对液氧/甲烷发动机的影响：数值分析

摘要 液氧/甲烷发动机是可重复使用运载火箭的理想动力。一般认为，液氧/甲烷发动机的效率主要受推力室喷射条件的影响。然而，由于燃烧实验的复杂性，很难获得特定喷射器对燃烧性能的确切影响。本文通过对典型的亚尺度推力室的分析，提出了三维数值模型来评估三个主要喷射器参数，即液氧柱的厚度、喷射器的数量和喷射器的类型对液氧的影响。 /甲烷发动机燃烧性能。模拟结果与现有实验数据在燃烧室压力、燃烧稳定性、以及壁面热通量。本文的研究结果表明，较大的液氧柱厚度和涡流同轴喷射器可以显着降低热通量，而喷射器数量的影响相对较小。此外，液氧柱厚度的减小可以提高燃烧效率。喷油嘴越少，燃烧越稳定。所提出的仿真模型提供了一种可靠且具有成本效益的方法来分析特定的喷射器参数，并为未来的液氧/甲烷发动机设计提供了新的原理。液氧柱厚度的减小可以提高燃烧效率。喷油嘴越少，燃烧越稳定。所提出的仿真模型提供了一种可靠且具有成本效益的方法来分析特定的喷射器参数，并为未来的液氧/甲烷发动机设计提供了新的原理。液氧柱厚度的减小可以提高燃烧效率。喷油嘴越少，燃烧越稳定。所提出的仿真模型提供了一种可靠且具有成本效益的方法来分析特定的喷射器参数，并为未来的液氧/甲烷发动机设计提供了新的原理。