温度对预混合乙烯火焰碳烟生成的影响

Effect of Temperature on Soot Formation in Premixed Ethylene Flames

基于碳烟测试标准方法（预混合稳定滞止火焰法）,研究火焰温度对预混合乙烯火焰中碳烟生成的影响,为发展和验证碳烟模型提供标准试验依据.试验表明：碳烟生成对火焰温度非常敏感.火焰温度约在1,650～1,750,K范围内对碳烟生成更有利,碳烟体积分数更高;在此范围之外,火焰温度对碳烟生成都有一定的限制作用;当火焰温度约为1,580,K时,反应动力学速率较低,碳烟成核与长大缓慢,碳烟体积分数较低;当火焰温度约为1,872,K时,尽管此时碳烟成核反应动力学速率较高,但受碳烟成核过程热力学可逆性的影响,碳烟成核与长大显著受限,碳烟体积分数显著降低.

To provide a canonical data sets for the improvement and validation of soot models,effects of flame temperature on soot formation in premixed ethylene flames was studied based on the standard method of soot measurement（premixed stabilized stagnation flame method）.Results show that soot formation is highly sensitive to flame temperature.Soot volume fraction is higher at flame temperature range of 1,650-1,750,K,the best environment for soot growth.Beyond this range,soot formation is somewhat controlled.At flame temperature of 1,580,K,the lower rate of soot nucleation and growth caused by lower kinetic reaction rate leads to a lower soot volume fraction.At flame temperature of 1,872,K,although the kinetic reaction rate of soot nucleation is higher,soot volume fraction is significantly decreased because soot nucleation and growth are severely limited by the thermodynamic reversibility of the nucleation process.