微细直管燃烧器的散热损失研究  

Investigation on Heat Loss of Microtube Combustor

作　　者：李军伟[1] 钟北京[1] 

机构地区：[1]清华大学航天航空学院,北京市海淀区100084

出　　处：《中国电机工程学报》2007年第20期59-64,共6页Proceedings of the CSEE

基　　金：国家自然科学基金项目(50376027)~~

摘　　要：为了解微细直管燃烧器散热损失的大小,采用内径为0.6mm的微细陶瓷管进行氧气和甲烷气体的燃烧实验,测量了微细直管外壁面的温度,研究了氧气和甲烷的总流量和质量比对壁面散热的影响,以及不同总流量下直管壁面温度的动态变化过程。研究结果表明,混合比小于当量混合比时,随着混合比的增加,燃烧放热功率增加,壁面温度升高,管壁的散热功率增加:管壁的散热量占了很大一部分燃烧放热量,文中测量的管壁散热量最大为燃烧放热量的42%;在管壁散热量中,辐射散热量占很大一部分,最大达到总散热量的65%;随着总流量的增加,燃烧反应区的长度增加,轴向的壁面温差减小,壁面升温速率增大。To understand heat loss characteristics of micro-combustor, combustion of CH4/O2 took place in a ceramic tube with inner diameter of 0.6mm, and temperature on the outer wall of the tube was measured. In the combustion tests, influence of total mass flow rate and mass ratio of O2 and CH4 on the heat loss of the tube wall was studied. The tests＇ results show that when mixture ratio is lower than the stoichiometric ratio, with the increase of ω（O2）/ω（CH4）, combustion heat power increases. Therefore, wall temperature rises and heat loss power increases. The heat loss power occupies a very large proportion of the combustion power and the largest in the tests is 42%. However, in the wall heat loss, radiative heat loss accounts for a large part and the largest reaches 65% of the total heat loss. When the mass flow rate of O2 and CH4 is increased, combustion zone in the micro-tube is enlarged and temperature difference along the tube wall becomes smaller. Meanwhile, the combustion heat power and wall temperature variation rate increase.

关 键 词：微小燃烧室 热损失 燃烧实验 甲烷 氧气 

分 类 号：TK16[动力工程及工程热物理—热能工程]