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论文类型：期刊论文

发表时间：2014-11-01

发表刊物：JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES

收录刊物：SCIE、EI、Scopus

卷号：32

页面范围：127-134

ISSN号：0950-4230

关键字：Organic dust explosion; Flame propagation behaviors; Flame temperature; Ion current; Flame microstructures

摘要：To reveal clearly the effects of particle thermal characteristics on flame microstructures during organic dust explosions, three long-chain monobasic alcohols, solid at room temperature and similar in physical-chemical properties, were chosen to conduct experiments in a half-closed chamber. In the experiments, the dust materials were dispersed into the chamber by air to form dust clouds and the hybrids were ignited by an electrical spark. A high-speed optical schlieren system was used to record the flame propagation behaviors. A fine thermocouple and an ion current probe were respectively used to measure the flame temperature profile and the reaction behaviors of the combustion zone. Based on the experimental results, combustion behaviors and flame microstructures in dust clouds with different thermal characteristics were analyzed in detail. As a result, it was found that the dust flame surfaces were completely covered by cellular structures that significantly increased the flame frontal areas. Flame propagated more quickly and the number of the cellular cells increased as increasing the volatility of the particles. On the contrary, maximum temperature and the thickness of the preheated zone decreased as increasing the volatility of the particles. According to the ion current profile, the particles in the preheat zone were pyrolyzed to intermediate radicals and the radicals' fraction in the higher volatile dust flame was higher than that in the lower volatile dust flame. (C) 2014 Elsevier Ltd. All rights reserved.