Intensity Distribution and Inversion Reconstruction of Spectrum of
Hydroxyl Radicals in Spray Combustion of PODE Under Different
Environmental Oxygen Concentrations
ZHANG Xiao-teng, LIU Wei, LIU Hai-feng*, ZHENG Zun-qing, MING Zhen-yang, CUI Yan-qing, WEN Ming-sheng, YAO Ming-fa
State Key Laboratory of Engines, Tianjin University, Tianjin 300072, China
Abstract：Polymethoxy dimethyl ether (PODE) is a potential diesel alternative fuel. However, currently, most of the research on PODE is concentrated on the engine bench tests, and corresponding basic spray combustion research is few which restricts the improvement of its efficient and clean combustion performance in power plants. The property of hydroxyl groups is active, and the area where they exist in large quantities is usually considered a high-temperature reaction area. By measuring the hydroxyl spectral band, important parameters such as flame structure, combustion reaction location and heat release rate can be obtained. Environmental oxygen concentration has a great influence on flame structure, and it is also an important parameter in controlling combustion reaction rate and pollutant emission. Therefore, on an optical constant volume combustion bomb, firstly used the self-luminescence measurement of hydroxyl spectral band to research the effects of oxygen concentration (15%~80%) on the lift-off length of PODE spray flame, then the integral value of hydroxyl self-luminescence spectrum intensity was converted to the point value by using Abel inverse transformation method to research the effects of oxygen-enriched concentration (40%~80%) on the hydroxyl distribution of PODE spray flame. The results show that: as the oxygen concentration increases from 15% to 40%, the flame lift-off length of PODE decreases rapidly. But further increase to 80%, the flame lift-off length decreases gradually until it is unchanged; The flame lift-off length of PODE is significantly smaller than diesel under the same oxygen concentration. At the distribution feature surface of hydroxyl spectral after inversion, the high-intensity area of PODE hydroxyl spectral is mainly concentrated in the thin layer of the spray edge diffusion flame under oxygen-enriched conditions; Meanwhile, the significant increase in local temperature makes the hydroxyl spectral intensity reach the maximum near the downstream of the premixed reaction zone. With the increase of oxygen concentration, the high-intensity area of hydroxyl spectral gradually migrates to the upper and middle areas of the flame. Its distribution appears to be shorter in the axial direction and narrower in the radial direction. When the flame reaches a quasi-steady state, compared with 40% oxygen concentration, the spectral intensity of hydroxyl at 60% and 80% oxygen concentration is significantly weaker in the middle and lower reaches of the flame, which indicates that the high concentration area of fuel upstream of the spray is more quickly to participate in the intense combustion reaction.
张晓腾，刘 威，刘海峰，郑尊清，明镇洋，崔雁清，文铭升，尧命发. 不同环境氧浓度下聚甲氧基二甲醚（PODE）喷雾燃烧的羟基光谱分布及其反演重构研究[J]. 光谱学与光谱分析, 2022, 42(08): 2587-2594.
ZHANG Xiao-teng, LIU Wei, LIU Hai-feng, ZHENG Zun-qing, MING Zhen-yang, CUI Yan-qing, WEN Ming-sheng, YAO Ming-fa. Intensity Distribution and Inversion Reconstruction of Spectrum of
Hydroxyl Radicals in Spray Combustion of PODE Under Different
Environmental Oxygen Concentrations. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(08): 2587-2594.
[1] LIU Hai-feng, WEN Ming-sheng, CUI Yan-qing, et al(刘海峰, 文铭升, 崔雁清, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2020, 40(7): 1998.
[2] Huang H Z, Liu Q S, Teng W W, et al. Applied Energy, 2018, 227: 38.
[3] Liu H F, Wang X C, Wu Y Y, et al. Fuel, 2019, 257: 116064.
[4] Ma Y, Cui L X, Ma X, et al. Fuel, 2020, 272: 117691.
[5] Liu J L, Feng L, Wang H, et al. Applied Thermal Engineering, 2019, 159: 113850.
[6] Duan X B, Xu Z X, Sun X Y, et al. Energy, 2021, 231: 121069.
[7] Nidhi, Subramanian K A. Applied Thermal Engineering, 2019, 147: 501.
[8] Feng L, Wang Q L, Liu H F, et al. Combustion and Flame, 2021, 227: 52.
[9] Sung Y, Choi G. Fuel, 2016, 174: 76.
[10] Nils E O, Per E B, Mattias R, et al. Sae International Journal of Engines, 2016, 9(2): 723.
[11] Maes N, Meijer M, Dam N, et al. Combustion and Flame, 2016, 174: 138.
[12] Zhang G Y, Wang G Q, Huang Y, et al. Optik, 2018, 170: 166.
[13] Yi W T, Liu H F, Feng L, et al. Fuel, 2021, 291: 120129.
[14] Wei Z L, Zhen H S, Leung C W, et al. Fuel, 2017, 195: 1.
[15] Zheng Z Q, Liu W, Liu H F, et al. Science China Technological Sciences, 2021, 64(8): 1611.
[16] He T J, Wang Z, You X Q, et al. Fuel, 2018, 212: 223.
