气氧甲烷单喷嘴燃烧室壁面热流的测量和数值模拟

Measurements and Numerical Simulation of Wall Heat Fluxesin a Single-Element GO2/GCH4 Rocket Combustor

关键词:  火箭燃烧室  壁面热流  数值模拟

Key words:  Rocket combustor  Wall heat flux  Numerical simulation

摘要:

为了研究气氧甲烷燃烧室的壁面热载荷，对一个包含同轴剪切喷嘴的燃烧室开展了热试研究，混合比2.647，室压2MPa。根据沿燃烧室轴向测得的壁面温度数据，利用逆向传热计算的方法获得了壁面热流分布。为了更好地分析实验结果，应用商业CFD软件ANSYS Fluent开展了相应的数值模拟研究，采用涡耗散概念模型模拟湍流燃烧过程。在进行分析之前对网格无关性进行了验证，比较了从数值模拟和实验获得的热流分布，结果表明所采取的模拟方法能够有效预测燃烧室壁面热流分布，最大热流值偏差17%，另外还从燃气温度场和流场结构方面分析了造成这种热流分布的原因。

Abstract:

In order to investigate the heat load of the combustion chamber fed with gaseous oxygen and gaseous methane， a rocket combustion chamber with a single coaxial shear injector is tested. The hot firing tests are conducted with gaseous methane and gaseous oxygen at a mass ratio of oxidizer to fuel of 2.647 and at a pressure of 2MPa. Wall temperatures are measured along the axis of the chamber and the wall heat fluxes are calculated based on inverse heat conduction approach. To better analyze the experimental results， numerical simulations are performed applying the commercial CFD code ANSYS Fluent. The eddy dissipation concept model is adopted to model turbulent combustion. Mesh independency studies have been performed prior to any further analyses. The ultimate target is to compare the heat fluxes obtained from simulation with the experimental data. The comparison demonstrates that the simulation approach adopted is capable to predict wall heat fluxes in a rocket combustor with sufficient accuracy and the relative deviation is 17% at maximum heat flux. Hot gas temperature distribution and flow field structures are also investigated for a better understanding of the experimentally determined heat flux profile.