Radiative heat transfer plays an important role in the chemical reactions in the combustor. The widely used WSGG model proposed by Smith is established for normal pressure, which shows inevitable computational errors when dealing with radiative heat transfer problems at reduced or elevated pressures. In this paper, an improved global model is established to calculate the radiant energy exchanges between combustion gases and combustor chamber walls. Compared with the Smith model, the new model shows better performance in a wide range of pressure regions. The model accuracy is examined by computing the emissivity, radiative heat flux as well as the radiative source of H2O–CO2 gas mixtures at different pressure values. Finally, the radiative heat transfer inside a 3D TBCC(turbine-based combined cycle) engine exhaust system where strong gradients of pressure and temperature exist, is also addressed. The computational results show that the developed model provides approximate results at much less computational costs than the high-precision MSMGFSK-c8 model, which makes it competitive in complicated combustion systems.

中文翻译：

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计算热燃烧气体辐射传热的改进模型

辐射传热在燃烧室的化学反应中起着重要作用。Smith 提出的广泛使用的 WSGG 模型是针对常压建立的，这表明在处理低压或高压下的辐射传热问题时不可避免地会出现计算错误。在本文中，建立了改进的全局模型来计算燃烧气体与燃烧室壁之间的辐射能交换。与 Smith 模型相比，新模型在较宽的压力区域表现出更好的性能。通过计算不同压力值下 H2O-CO2 气体混合物的发射率、辐射热通量以及辐射源来检查模型的准确性。最后，还讨论了 3D TBCC（基于涡轮的联合循环）发动机排气系统中存在强压力和温度梯度的辐射传热问题。计算结果表明，所开发的模型以比高精度 MSMGFSK-c8 模型低得多的计算成本提供近似结果，这使其在复杂的燃烧系统中具有竞争力。