【摘要】 聚甲氧基二甲醚(PODE)是一种有潜力的柴油替代燃料，目前针对PODE的研究更多集中在发动机台架试验，相应的基础喷雾燃烧研究较少，制约了其在动力装置中高效清洁燃烧性能的提升。羟基(OH)性质活泼，大量存在的区域通常认为是高温反应区域。利用羟基光谱可以获得火焰结构、燃烧反应位置以及热释放速率等重要参数。环境氧浓度对火焰结构有很大影响，也是控制燃烧反应速率和污染物排放的重要参数。因此，在一台光学定容燃烧弹上，首先利用羟基的自发光光谱测量，研究了宽环境氧浓度变化(15%～80%)对PODE喷雾火焰浮起长度的影响，进一步利用阿贝尔逆变换方法将羟基自发光光谱强度由积分值反演为点位值，研究了富氧条件下(40%～80%)氧浓度变化对PODE喷雾羟基分布的影响。研究结果表明：环境氧浓度由15%增至40%, PODE火焰浮起长度迅速缩短；氧浓度进一步增加至80%,火焰浮起长度下降趋势逐渐变缓，直至基本不变；相同氧气浓度下PODE火焰浮起长度明显小于柴油。反演后的羟基光谱分布特征表面，富氧条件下PODE羟基光谱的高光强区域主要集中于喷雾边缘扩散火焰薄层中，同时，局部温度的显著提升使得羟基光谱强度在预混反应区下游附近达到最大；羟基光谱高光强区域随氧气浓度增加逐渐向火焰中上游区域迁移，并且其分布表现为轴向上更短，径向上更窄；在火焰达到准稳态时，相较40%氧气浓度条件，60%和80%氧气浓度下的羟基光谱强度在火焰中下游明显减弱，表明高的环境氧浓度下喷雾上游的燃油高浓度区域更快的参与到剧烈的燃烧反应中。更多还原

【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.更多还原