基于假设气体法的燃气辐射特性计算模型

为了降低航空发动机排气系统高温燃气红外辐射特性的计算误差,发展了基于假设气体法的Malkmus统计窄谱带模型,并通过与逐线计算法的计算结果对比,验证了该模型的准确性。结果表明,基于假设气体法的Malkmus统计窄谱带模型能够显著降低非等温、非均匀高温燃气辐射特性参数的计算误差。在非等温、非均匀条件下,对CO₂-H₂O-N₂混合气体谱带平均透过率的计算结果表明,传统的Malkmus统计窄谱带模型的均方根误差为0.018,而基于假设气体法的Malkmus统计窄谱带模型的均方根误差为0.012,后者的计算误差相对前者降低了33.3%。

Fictitious gas-based model for calculating radiation characteristics of gas

The classical Malkmus statistical narrow-band model was extended with a fictitious gas method to improve the numerical accuracy of the infrared radiation signature of high-temperature gas in aeroengine exhaust systems. In this study, the accuracy of the extended model and the classical Malkmus statistical narrow-band model were evaluated. The results show that the numerical accuracy of the classical Malkmus statistical narrow-band model was improved significantly by the fictitious gas assumption, particularly for nonisothermal and nonhomogeneous gases. Compared with the line-by-line results, the root mean square error of the classical Malkmus statistical narrow-band model for the average band transmissivity of CO₂-H₂O-N₂ mixture is 0.018, while the root mean square error of the fictitious gas-based Malkmus statistical narrow-band model is 0.012, which is reduced by 33.3% compared with the former.