An improved two-color method, which originates from an approximate emissivity ratio model based on the empirical emissivity formula by Hottel and Broughton, was developed to measure the temperature field of soot flames generated on a McKenna burner in the present study. In conjunction with the onion-peeling method and Tikhonov regularization, the reconstructed temperature fields of rich ${\mathrm{C}}_2{\mathrm{H}}_4/\mathrm{air}$ soot flames under varied equivalence ratios were obtained by calculating the 550 and 650 nm spontaneous emission signal images, which were recorded by an intensified charge coupled device, respectively. At the same time, an autoscanning R-type thermocouple was used to measure flame temperature for validating the reconstructed data. The results show that the reconstructed temperature distributions agreed well with the measured data by thermocouple, and the reconstructed temperature is more precise by the present improved two-color method than by the classic two-color method based on a constant emissivity assumption.

在本研究中，基于 Hottel 和 Broughton 经验发射率公式的近似发射率比模型开发了一种改进的双色方法，用于测量 McKenna 燃烧器上产生的烟尘火焰的温度场。结合洋葱去皮方法和 Tikhonov 正则化，重建了丰富的温度场。${\mathrm{C}}_2{\mathrm{H}}_4/\mathrm{空气}$通过计算 550 和 650 nm 的自发辐射信号图像获得了不同当量比下的烟灰火焰，分别由增强的电荷耦合装置记录。同时，使用自动扫描R型热电偶测量火焰温度以验证重建数据。结果表明，重建的温度分布与热电偶测得的数据吻合较好，改进后的双色法重建的温度比基于恒定发射率假设的经典双色法更精确。