摘要
针对CH_4这种特别气体,对其实验结果运用数字化处理方法研究CH_4稳定性.在内径50.8 mm圆形管道内获得CH_4+2O_2预混气在不同初始压力条件下的胞格爆轰结果并使用烟膜记录,且测得的平均爆轰速度数据与CJ爆轰速度接近,在初始压力高于5 k Pa时爆轰可稳定传播.烟膜上形成的三波点轨迹十分不规则.为减少人为误差,使用改进后的数字化处理烟膜图像的技术方法,从烟膜轨迹中得出柱状图及自相关函数结果,发现CH_4+2O_2是一种爆轰十分不稳定的气体,并给出CH_4+2O_2预混气的爆轰胞格尺寸及差距,结果显示人为测量结果偏大而数字化处理方法更为准确.这种方法能计算CH_4+2O_2预混气胞格尺寸及不稳定度,完善了定量化预混气不稳定程度的方法.
CH4 is a typical and special detonation mixture. Based on the experimental method, digital image processing was performed to study the detonation stability theory of methane. A premixed CH4 ＋ 202 mixture was ignited in a tube with an inner diam- eter of 50. 8 mm under different initial pressures. Smoked foils were used to record the cellular structure of spinning detonation. The average detonation velocity measured is similar with the CJ detonation velocity and it demonstrates that steady detonation happens when the initial pressure is higher than 5 kPa. The triple point trajectory leaves a very irregular pattern in smoked foils. In order to decrease human error, the digital processing technology was utilized and improved. The CH4 ＋ 2O2 mixture shows high degree of irregularity in the computation of histograms and the autocorrelation function. The cellular size and gap of the unstable premixed CH4 ＋ 2O2 were given. It is found that the results measured by digital image processing are accurate and by eyes are too big. The research can calculate the cellular size and the degree of instability of the unstable premixed CH4 ＋ 202 and improves the quantitative irregular calculation method.
出处
《工程科学学报》
EI
CSCD
北大核心
2016年第11期1522-1531,共10页
Chinese Journal of Engineering
基金
国家自然科学基金资助项目(E041003)
国家自然科学基金青年科学基金资助项目(E11602017)
中央高校基本科研业务费专项资金资助项目(FRF-TP-15-105A1)
中国博士后科学基金资助项目(2015M580049)
关键词
甲烷
爆轰
定量分析
不规则性
图像处理
自相关
methane
detonation
quantitative analysis
irregularities
image processing
autocorrelation
作者简介
通信作者，E-mail：zyhustb@163．com
