Abstract The banded approach or box model is a method to include the non-grayness of combustion gases in radiation heat transfer calculations. However, the determination of the correct limits for the bands and the effective band absorption coefficients is still something of a black art. In this study, the line by line (LBL) spectral absorption coefficient profile has been implemented to obtain the effective number of bands, and bands’ limits for pure H2O, pure CO2 and a H2O-CO2 gas mixture. A mathematical technique has been used to smooth the LBL profiles of pure gases in atmospheric pressure in order to be used for identifying the gray bands. The optimization for selecting the bands is done by analyzing the radiative heat transfer in several one-dimensional benchmarks. After obtaining the optimal band dividing scheme, a set of correlations for the pressure based gray band absorption coefficient of pure gases is found by integrating the line by line spectral absorption coefficient weighted by the corresponding black body intensity along the bands. In contrary to the previous similar works, by using the LBL data for pressure based gray absorption coefficient of the bands, the current correlations are independent of gas concentration and path length. The present approach could successfully support the non-gray walls. The method has been validated using several benchmarks and exhibited comparable accuracy with other available models.

中文翻译：

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基于带状方法的非灰色气体建模的逐行带识别

摘要 带状方法或箱模型是一种在辐射传热计算中包含燃烧气体非灰度的方法。然而，确定波段的正确限制和有效波段吸收系数仍然是一种黑色艺术。在本研究中，已实施逐行 (LBL) 光谱吸收系数剖面，以获得有效波段数，以及纯 H2O、纯 CO2 和 H2O-CO2 气体混合物的波段限制。已使用数学技术来平滑大气压下纯气体的 LBL 轮廓，以便用于识别灰色带。选择波段的优化是通过分析几个一维基准中的辐射传热来完成的。得到最优频带划分方案后，通过对由相应黑体强度沿带加权的逐线光谱吸收系数进行积分，可以找到一组基于压力的纯气体灰带吸收系数的相关性。与之前的类似工作相反，通过使用基于压力的波段灰度吸收系数的 LBL 数据，当前的相关性与气体浓度和路径长度无关。本方法可以成功地支撑非灰色墙壁。该方法已经使用多个基准进行了验证，并且表现出与其他可用模型相当的准确性。与之前的类似工作相反，通过使用基于压力的波段灰度吸收系数的 LBL 数据，当前的相关性与气体浓度和路径长度无关。本方法可以成功地支撑非灰色墙壁。该方法已经使用多个基准进行了验证，并且表现出与其他可用模型相当的准确性。与之前的类似工作相反，通过使用基于压力的波段灰度吸收系数的 LBL 数据，当前的相关性与气体浓度和路径长度无关。本方法可以成功地支撑非灰色墙壁。该方法已经使用多个基准进行了验证，并且表现出与其他可用模型相当的准确性。