Analysis Of Reaction Dynamics And Study On Optical Characteristic Of Gas Explosion In Induction Period

It is the first of the most important assignment for the safety production in mine to prevent the gas explosion accident. It is also an aspect of achieving the simultaneous extraction of coal and coal bed gas. The gas explosion accident is result in the action of many factors, which relates to many difficult questions of theories and experiments. The difficult course of gas explosion accident leads to the limitation of the techniques used to prevent gas explosion accident. The analysis of reaction dynamics and the study on optical characteristic of gas explosion in induction periods offer the data for developing the techniques of detecting gas explosion and are the base of developing the techniques of controlling gas explosion.In this paper, the reaction dynamics of gas explosion are analyzed base on the thermal reaction theory and chain reaction theory. The conceptd and the dynamics description of the induction period of gas explosion are clarified. The gas explosion experiments are made in the improved equipment system of gas explosion experiment and in another new one. The data are analyzed by software named MATLAB used to analyze images. The location and the rate of the flame front of gas explosion are analyzed. The criterion of judging gas explosion is educed, base on which the way of ascertaining the induction period of the combustion, translation from combustion to explosion and explosion is educed. The characteristic parameters of the image and spectrum of the flame and the analysis way are educed. The flame image optical characteristic in induction period of gas explosion is analyzed in detail, which belongs to 31 groups of experiments with 7 different concentrations of gas. The difference of image optical characteristic of the flame with the nature background and the electric spark emitted by the ignition is also analyzed in detail. The flame spectral characteristic in induction period of gas explosion is analyzed in detail, which belongs to 51 groups of experiments with 12 different concentrations of gas. The difference of spectral characteristic of the flame with the nature background, interferential background and the electric spark emitted by the ignition is also analyzed in detail. 10 kinds of radicals and 5 kinds of numerators existing possibly in the flame of gas explosion in the induction period are educed, and the appearance times and the distribution of the spectral band emitted by them is analyzed. The conception and the principle of the gas explosion detector system in the induction period is put forward, which shows the applied significance of the study in this paper. The way of identifying the flame of gas explosion by the optical characteristic in the detector system is analyzed in detail. The Trend-Persistence method, Perceptron Neural Networks and Back Propagation Neural Networks is used to identify the flame of gas explosion. The identification of the flame of gas explosion in the induction period is carried out in experiment condition.