Forced Airflow Under The Smoldering Formation And Propagation Mechanism And Its Product Characteristics Pilot Study

With the further research on fire, smolder, as a special combustion, comes into the focus of people's attention. The typical example of smolder is smoldering cigarettes make beddings or bed sheets smolder, then lead to the occurrence of fire in the room. In recent years, more attention is paid to the fire led by solid combustible smolder, and the research on smolder, consequently, becomes an important part of fire science. In research, this thesis establishes a special experimental apparatus to simulate one-dimension forward and opposed smoldering. And the research contents include formation, propagation of smolder, and product in smolder. Through investigation, thesis is expected to make mechanism of smolder understood well, provide enough evidences for controlling and eliminating smolder, and reduce the loss of fire produced by smolder.At first, this paper is concerned with influencing factors on the formation of smolder, including heating power, velocity of oxidizer and heating time. The results of experiments indicate that the formation of forward smolder is easier than that of opposed smolder in the same heating condition.In this article, plenty of experiments on propagation of smolder are conducted. The propagation processes of two modes of smolder are investigated. In addition, the influences on propagation rate by oxidizer velocity in different smolder are researched. In the end, experiments are conducted on the smolders of wood and paper mixture The paper studies the product of smolder, including gas, solid and liquid (tar), including: 1 In a series of experiments, the densities of CO CO2 in two different modes of smolder are analyzed. Based upon experiments, AER (average emission rate) of the emissions of CO and CO2 in two modes of smolder are calculated.2 Elemental and industrial analyses and TG experiments on origin wood and solid product of smolder are studied. In this part, chemical kinetics parameters are also gained. 3 The GC-FTIR analysis of the tar from wood smolder are conducted in this part. The results show that there are certain acid, ketone, aldehyde, and alcohol in the tar, which contain methyl, eshyl, methoxyl, or hydroxyl and so on. Probably, the tar contains certain funan ordeverivant of furfural. In the chemical compounds mentioned above, most are harmful to people. Therefore, toxic analysis on product of smolder is of great importance.This paper also establishes the experiments for emission of PAH in wood smolder on special collecting apparatus and in detection routine. The conclusions from the experiments are important for us to know the emission of PAH in smoldering and the harm of smolder.A great deal of experiments on smolder are conducted in this paper, the results of which enrich the theory of smolder, arid make us know smolder much deeper. At the same time, this paper is expected to be used for reference for future research on smolder.