火箭发动机羽流红外特性计算方法研究

Research on the calculation method of infrared signature of rocket motor exhaust plume

关键词:  火箭发动机羽流  红外辐射  耦合求解  有限体积法  离散坐标法

Key words:  Rocket motor exhaust plume  Infrared radiation  Coupled solution  Finite volume method  Discrete ordinates method

摘要:

为研究火箭发动机羽流近场的红外辐射特性,建立了羽流红外辐射传输的计算模型,通过在能量方程中引入辐射源项,实现了流场计算与辐射传输的耦合求解。计算中考虑了7种主要燃气组分,分别使用有限体积法和离散坐标法求解羽流流场和辐射传输方程,得到了羽流红外辐射强度在1～15μm范围内随波长变化的曲线及辐射强度在近场内的分布云图,均与文献的计算结果和红外试验热图符合较好。在羽流近场内能够捕捉到流场内各点辐射强度随流场物性变化的情况,表明耦合求解能提高辐射计算精度。

Abstract:

To study the infrared signature of rocket motor exhaust plume,the calculation model for infrared radiation transfer of rocket motor was built.The radiation source item was induced to energy equation,thus the plume flowfield and radiation transfer was calculated together.Finite volume method and discrete ordinates method were separately used to solve the plume flowfield of multi-species without chemical reactions and the radiation transfer equation.Thus infrared radiation(IR) signature of exhaust plume of rocket motor was obtained.Seven main species were included in the exhaust plume.The spectral radiation intensity from 1 μm to 15μm and radiation intensity contours were obtained,and both of them agree well with the results from open literature and IR experimental images.The results show that the IR characteristics near the plume field captured change with the physical characteristics of flowfield,which shows that the coupled solution can increase the calculation resolution.