基于假设气体法的燃气辐射特性计算模型

Fictitious gas-based model for calculating radiation characteristics of gas

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CO_(2)-H_(2)O-N_(2)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%。

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 narrowband 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 CO_(2)-H_(2)O-N_(2) 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.