高浓度二氧化碳烟气辐射换热特性分析与计算

Analysis and calculation on the characteristics for radiative heat transfer of flue gas with high carbon dioxide concentration

介绍了常规辐射特性计算方法、逐线计算方法和基于光谱法窄谱带模型的Leckner方法,采用Leckner方法对二氧化碳烟气辐射特性进行计算并与常规计算和逐线计算进行比较,结果表明由于范围限制常规方法不适用于高浓度二氧化碳烟气辐射特性计算,Leckner方法能保证足够精度,较之传统方法有着更广泛的适用范围,可用于高浓度二氧化碳烟气辐射特性计算;采用Leckner方法计算表明,在高浓度二氧化碳烟气中,发射率随烟气温度的增加而降低,随辐射层厚度的增加而升高。

The conventional radiation characteristics methods line - by - line calculation method and the Leckner method which based on the narrow spectrum model were introduced, using Leckner methods to calculate the radiative characteristics of carbon dioxide flue gas and compare with the conventional methods and line - by - line calculation method. The results indicate that because of the limitation of the application scope the conventional methods not suit- able for calculating it, the Leckner method can guarantee sufficient accuracy and also have a broader applications scope can be used for calculating the radiative characteristics of flue gas with high carbon dioxide concentration. Apply the Leckner method calculations show that the gas emissivity fall with the increasing gas temperature and increases with the increasing path length.