摘要
为实现煤粉连续旋转爆轰发动机的可靠点火,探究煤粉质量浓度及表观形貌对煤粉/乙烯/氧气起爆特性的影响机制。在乙烯氛围下(初始总压100 kPa,当量比0.5),采用高能电点火装置对不同煤粉当量比和表观形貌下的煤粉-氧气混合物进行直接起爆实验。实验结果表明:添加少量5PA煤粉(实验所用2种煤粉记为PA、FA。PA和FA分别为多孔状无烟煤和片状无烟煤的缩写,如5μm多孔状煤粉简写为5PA煤粉)后,乙烯/氧气混合物的临界起爆能量迅速减小,在全局当量比0.7处达到其最小值2.53 J,随着当量比继续增加,煤粉/乙烯/氧气混合物的临界起爆能量逐渐增加;在全局当量比1.0处5FA煤粉的临界起爆能量(5.20 J)高于5PA煤粉的临界起爆能量(2.95 J);在5.80 J的点火能量下,5PA煤粉和5FA煤粉在全局当量比0.7~1.5内均可直接起爆,在4.10 J的点火能量下,5PA煤粉在全局当量比0.7~1.5内均可直接起爆,但5FA煤粉仅在全局当量比0.7处可直接起爆,进一步增加当量比后不可起爆。研究结果表明:对于贫燃料乙烯/氧气(当量比低于1),在一定煤粉质量浓度范围内,煤粉可以促进爆轰波的形成和自持传播,但煤粉质量浓度过高会抑制爆轰波的形成和自持传播;煤粉的表观形貌会影响煤粉混合物的起爆特性,相较于片状煤粉,多孔状煤粉的化学反应速率更高,临界起爆能量更低,更容易起爆。
In order to realize the reliable ignition of coal particle continuous rotating detonation engine,this study investigated the influence mechanism of coal particle concentration and apparent morphology on the initiation characteristics of coal/ethylene/oxygen mixture.Under the ethylene atmosphere(Initial total pressure is 100 kPa,equivalent ratio 0.5),a high-energy electric ignition device was used to carry out the direct initiation experiments on the coal-oxygen mixture under different coal particle equivalent ratios and apparent morphologies.The experimental results are as follows:after adding a small amount of 5PA coal particle(the two kinds of coal particle used in the experiment are recorded as PA and FA respectively.PA and FA are the abbreviations of porous anthracite and flaky anthracite respectively,such as 5μm por-ous coal particle can be shortened to 5PA coal particle),the critical initiation energy of the ethylene/oxygen mixture de-creases rapidly,reaching its minimum value of 2.53 J at the global equivalent ratio of 0.7,and the critical initiation energy of the coal/ethylene/oxygen mixture gradually increases as the equivalent ratio continues increasing.The critical initiation energy(5.20 J)of 5FA coal particle at the global equivalent ratio of 1.0 is higher than the critical initiation energy of 5PA(2.95 J).Under the ignition energy of 5.8 J,the 5PA coal particle and 5FA coal particle can be directly detonated in the range of global equivalent ratio 0.7−1.5.Under the ignition energy of 4.10 J,the 5PA coal particle can be directly deton-ated in the range of global equivalent ratio 0.7−1.5,but the 5FA coal particle can only be directly detonated at the global equivalent ratio of 0.7,and cannot be detonated after further increasing the global equivalent ratio.The research results show that,for lean fuel ethylene/oxygen(equivalent ratio less than 1),coal particle can promote the formation and self-sus-taining propagation of the detonation wave within a certain mass concentration range of coal particle,but the high concen-tration of coal particle would inhibit the formation and self-sustaining propagation of the detonation wave.The apparent morphology of coal particle would affect the detonation initiation characteristics of coal particle mixture.Compared with the flaky coal particle,the porous coal particle has a higher chemical reaction rate leading to a lower critical initiation en-ergy,so it is easier to be detonated.
作者
熊凯
罗永晨
杨浅舒
张锋
续晗
郑权
翁春生
XIONG Kai;LUO Yongchen;YANG Qianshu;ZHANG Feng;XU Han;ZHENG Quan;WENG Chunsheng(National Key Laboratory of Transient Physics,Nanjing University of Science and Technology,Nanjing 210094,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2024年第7期3235-3244,共10页
Journal of China Coal Society
基金
国家自然科学基金资助项目(12002167)
瞬态物理国家重点实验室基金资助项目(6142604200203)。
关键词
动力机械及工程
临界起爆能量
容弹实验
直接起爆
煤粉爆轰发动机
power machinery and engineering
critical initiation energy
detonation bomb experiment
direct initiation
coal particle detonation engine
作者简介
熊凯(2000—),男,湖南永州人,硕士研究生。E-mail:xiongkai@njust.edu.cn;通讯作者:续晗(1990—),男,四川成都人,副教授,硕士生导师,博士。E-mail:xuhan@njust.edu.cn。
