固液混合火箭发动机尾焰的红外特性研究

针对固液混合火箭发动机中Al2O3颗粒运动的影响，对喷管的内流场和外流场进行了一体化数值仿真，得到了温度、压力、组分浓度以及粒子浓度等参数的分布。利用以最新的分子光谱数据库HITRAN和HITEMP为基础编写的逐线积分法计算了气体光谱吸收系数，采用米氏散射模型计算了固体粒子的辐射特性参数。利用基于有限体积法离散辐射传输方程的模型计算出了尾焰的红外辐射亮度。通过进一步求解，得到了特定波段的光谱辐射强度。在8—14岬波段，利用红外热像仪进行了试验，并将试验结果与数值计算结果进行了比较。结果表明，该计算模型和方法能较好地模拟固液混合火箭发动机尾焰的红外辐射特性。

Study of Infrared Radiation Characteristics of Hybrid Rocket Engine Exhaust Plume

According to the motion of the A1203 particles in a hybrid rocket engine, the inside and outside flow fields of the engine nozzle are simulated numerically and integrally. The parameters such as temperature, pressure, composition concentration and particle concentration are obtained. The gas spectral absorption coefficient is calculated by a line-by line integration method based on the latest HI- TRAN and HITEMP databases. The radiation characteristic parameters of solid particles are calculated by using Mie＇s theory. The infrared radiation intensity of plume is calculated by using a model based on the discrete radiation transfer equation of the finite volume method. Through further solution, the spectral radiation intensity in particular wavebands are obtained. Finally, practical tests are carried out by using a thermal imager operating in the waveband from 8 μn to 14 lim and are compared with the numerical calculation results. The result shows that this calculation model and method can simulate the infrared radiation characteristics of the exhaust plumes from hybrid rocket engines well.