限制域、预混气初始温度对多孔介质表面火焰熄火特性的影响

Effect of restricted domain and premixed gas initial temperature on the flame blow-out performance of surface flame on porous media surface

为了对基于多孔介质表面火焰的微型燃烧室技术进行优化设计,以甲烷/空气预混气为研究对象,针对不同的限制域、预混气初始温度,开展了多孔介质表面火焰熄火特性实验研究.实验结果表明：在石英玻璃限制域下,多孔介质表面火焰可以维持在0.188-0.436m/s的低预混气速度下,速度升高容易发生推举和吹熄;而限制域的长度未产生影响作用;随着预混气初始温度从293K升高至550K,多孔介质表面火焰的熄火速度极限得以提高.当量比为1.0时,预混气熄火速度从293K的1.176m/s增加至550K的2.678m/s,并存在不同斜率的上升过程,而初始温度对熄火本质没有影响.

To optimize a micro combustor based on porous media dome,the influences of the restricted domain and initial temperature of premixed gas on the blow-out performance of surface flame on porous media surface were investigated experimentally.The premixed gas of methane and air was experimental subject.The results show that with the quartz glass restricted domain,surface flame on porous media surface can only be maintained when the speed of the premixed gas is low（0.188-0.436m/s）.It is easier to be blown out when the speed of premixed gas is increasing.However,restricted domains with different lengths produce no differences.When the premixed gas initial temperature increases from 293Kto 550K,the blow-out velocity of surface flame on porous media surface becomes higher.When the equivalence ratio equals 1.0,the blow-out velocity of initial premixed gas increased from1.176m/s（293K）to 2.678m/s（550K）.There are two rising processes with different slopes.In this condition,initial temperature of premixed gas doesn＇t yield essentially impact on the blow-out performance.