通过建立电预热式多孔介质燃烧实验系统，在不需二次点火情况下，实现了液体燃料的预蒸发自维持燃烧.在确定电预热温度场稳定性基础上，分析了柴油在多孔介质内预蒸发燃烧的火焰特征与温度场变化规律，讨论了当量比和空气流量对燃烧特性的影响.结果表明：电预热系统具有很强的稳定性，维持稳定燃烧所需的最低预热温度约为750℃；实验观察到液体预蒸发燃烧过程中出现了稳定火焰和过滤燃烧火焰两种火焰形态；稳定火焰与气体预混合燃烧火焰类似，火焰区最高温度可达 1140.2℃，过滤燃烧火焰传播速度约为1m/s；随着空气流量的增加，火焰面向下游移动且燃烧更加完全；当量比对温度分布影响较大，但其对火焰传播的影响相对较小.
Experimental system of porous medium burner with electric preheating was developed to realize a self-sustaining combustion of liquid fuel without second ignition. Based on the stability of the electric preheating temperature field, the flame characteristics and the temperature variation of the diesel oil pre-evaporation combustion within porous media were analyzed, and the influences of the equivalence ratio and the air mass flow on the combustion characters were discussed. The results indicate that the electric preheating system shows a strong stability, and the minimum preheating temperature for a stable combustion is about 750℃. Two types of flame forms, the stable flame and the filtration combustion flame, are found during the process of the liquid fuel pre-evaporation combustion. The highest temperature of the stable flame which is similar to the premixed combustion is 1140.2℃, and the propagation velocity of the filtration combustion flame is near 1m/s. As the gas mass flow increases, the stable flame moves to downstream and the burning becomes more completely. Equivalence ratio has more significant effect on the temperature distribution than that on flame propagation.
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