瓦斯煤尘爆炸特性及抑爆方法研究进展

为探究瓦斯煤尘爆炸特性及抑爆机理,本文通过一系列实验,研究瓦斯、煤尘爆炸的速度和温度等特征,提出利用图像相关系数法和辐射测温原理计算火焰传播速度及温度场变化,定量分析影响煤尘爆炸的因素以及产物变化规律,揭示煤尘爆炸的宏微观机制。结果表明:火焰分形维数可以用来反应瓦斯爆炸强度,即当分形维数更接近2.2937时爆炸反应最为强烈,其爆炸过程中自由基最终生成浓度与CH 4初始浓度呈倒U型关系;当量比对煤粉火焰爆炸压力及速度也有一定影响,在最佳当量比的2倍左右时可以达到最大爆炸压力和最大火焰传播速度。另外本文亦采用泡沫陶瓷对瓦斯的多次爆炸和连续爆炸进行抑爆,发现不同厚度和孔隙的泡沫陶瓷具有不同的抑制效果,孔隙较大的泡沫陶瓷对爆炸能量有较好的抑制作用。

Research Progress on Explosion Characteristics and Explosion Suppression Methods of Gas and Coal Dust

In order to explore the explosion characteristics and explosion suppression mechanism of gas and coal dust,through a series of experiments,the features such as velocity and temperature of explosion of gas and coal dust were studied.The flame propagation velocity and temperature field change were measured by using the image correlation coefficient method and the radiation temperature measurement principle.The factors affecting the coal dust explosion and the product change law were analyzed quantitatively,and the macroscopic and microscopic mechanism of coal dust explosion was revealed.The results showed that the flame fractal dimension could be used to reflect the intensity of gas explosion.That is,the explosion reaction is the strongest when the fractal dimension is closer to 2.2937.The relationship between the final concentration of free radical formation and the initial concentration of CH 4 is inverted U-shaped.The equivalent ratio also has some influence on the explosive pressure and velocity of pulverized coal flame.The maximum explosive pressure and maximum flame propagation velocity can be reached when the optimum equivalent ratio is about two times.In addition,foam ceramics were also used in this paper to suppress multiple and continuous explosions of gas.It was found that foam ceramics with different thickness and pores had different inhibition effects,and foam ceramics with larger pores had better inhibition effect on explosion energy.