CAJ | 학술논문

采用对冲火焰实验系统对贫燃料甲烷/空气湍流火焰发生熄灭的极限条件进行考察，分析了平均流场拉伸和湍流拉伸对火焰熄灭的影响。实验结果表明，随着甲烷/空气火焰当量比的增大，其熄灭时的射流平均速度以及平均拉伸率随之增大，说明平均拉伸对火焰熄灭极限有显著影响。当量比增大时，湍流极限拉伸率和Karlovitz拉伸参数Ka 均增大，这与前人的实验结果一致，但由于平均拉伸的影响，当量比一定时，Ka 的数值比文献数据偏小。根据实验数据，文中对湍流预混火焰熄灭的机制进行了探讨。
채용대충화염실험계통대빈연료갑완/공기단류화염발생식멸적겁한조건진행고찰，분석료평균류장랍신화단류랍신대화염식멸적영향。실험결과표명，수착갑완/공기화염당량비적증대，기식멸시적사류평균속도이급평균랍신솔수지증대，설명평균랍신대화염식멸겁한유현저영향。당량비증대시，단류겁한랍신솔화Karlovitz랍신삼수Ka 균증대，저여전인적실험결과일치，단유우평균랍신적영향，당량비일정시，Ka 적수치비문헌수거편소。근거실험수거，문중대단류예혼화염식멸적궤제진행료탐토。
Extinction of premixed turbulent methane/air flames was studied in a counterflow burner,and the effects of bulk and turbulent straining on the extinction limits were analysed. The experimental results show that the average jet velocity and bulk stretch rate at extinction increase as the equivalent ratio increases,indicating a significant influ-ence of the bulk straining on flame extinction. With the equivalent ratio increasing,the critical value of turbulent stretch rate and Karlovitz number,Ka,for flame extinction both increase. Although the observation is consistent with previous experiments,the present value ofKa is smaller than literature data for the same equivalent ratio due to the effect of bulk straining. Based on the experimental results,the mechanism of turbulent flame extinction was dis-cussed.