Oxy-fuel combustion has drawn much attention as a promising CO₂ capture and storage/sequestration technology. Radiative heat transfer of oxy-fuel flames is more important than that of conventional flames owing to higher concentrations of radiating gases. The Full-Spectrum Correlated K-distribution (FSCK) methods with original correlated-K scheme (Modest and Zhang, 2002), the improved one (Cai and Modest, 2014), and the rank correlated one (Solovjov and Webb, 2018) provide obvious errors in the low-temperature regions of dry and wet oxy-fuel flames. To improve the accuracy of FSCK, the accuracy of the Multi-Group FSK (MGFSK) method with the three correlated-K schemes and two grouping strategies based on the scaling function and intervals of comonotonicity are investigated in two 1D, a 2D and a 3D oxy-fuel flames. The results show that MGFSK with different correlated-K schemes and grouping strategies demonstrate better accuracies than corresponding FSCK for both dry and wet oxy-fuel flames. MGFSK reduce the dependence of FSCK on the reference (or Planck) temperature and flame scale. The volume-averaged mole fractions of the maximum and minimum temperatures are recommend as the high- and low-temperature grouping states respectively. Dividing the spectral absorption coefficients into 2 to 4 groups is a good compromise between accuracy and efficiency.

含氧燃料燃烧作为一种有前途的CO ₂备受关注捕获和存储/隔离技术。由于较高的辐射气体浓度，含氧燃料火焰的辐射热传递比常规火焰更重要。提供具有原始相关K方案的全谱相关K分布（FSCK）方法（Modest和Zhang，2002），改进的方法（Cai和Modest，2014）和秩相关的一种（Solovjov和Webb，2018）提供在干和湿的含氧燃料火焰的低温区域存在明显的误差。为了提高FSCK的准确性，在两个1D，2D和3D中研究了具有三个相关K方案和基于缩放函数和同调性间隔的两个分组策略的多组FSK（MGFSK）方法的准确性氧燃料火焰。结果表明，对于干式和湿式含氧燃料火焰，具有不同相关K方案和分组策略的MGFSK的准确度均高于相应的FSCK。MGFSK降低了FSCK对参考（或普朗克）温度和火焰标度的依赖性。建议将最高和最低温度的体积平均摩尔分数分别作为高温和低温分组状态。将光谱吸收系数分为2至4组是准确度和效率之间的良好折衷。建议将最高和最低温度的体积平均摩尔分数分别作为高温和低温分组状态。将光谱吸收系数分为2至4组是准确度和效率之间的良好折衷。建议将最高和最低温度的体积平均摩尔分数分别作为高温和低温分组状态。将光谱吸收系数分为2至4组是准确度和效率之间的良好折衷。