为确保更好的煤与瓦斯突出模拟试验效果,针对原研制的模拟试验台存在的不足,对其突出模具及其配套的煤试件成型装置进行改进和重新研制。利用环向和面密封等全方位密封技术可使突出模具在2MPa瓦斯压力下达到较长时间的良好密封效果;依靠3组直径不同的圆形突出口装配,可在不更换突出模具的条件下进行不同突出口径的煤与瓦斯突出模拟试验,经济实用;凭借布置的温度和瓦斯压力传感器与配套的试验控制软件连接,可较方便地实时监测突出过程中煤体内温度及其瓦斯压力的变化规律;研制的独立煤试件成型装置可准确实施预定的成型压力,且操作过程较为灵活、方便。利用改进后的煤与瓦斯突出模拟试验台开展的模拟试验表明,在瓦斯压力、突出口径方面均存在一个使煤与瓦斯突出发生与否的阈值,高于此阈值时,瓦斯压力或突出口径愈大则突出强度亦愈大,且瓦斯压力作为突出发生的动力同时也对突出煤粉有一定的粉碎作用。此外,煤与瓦斯突出过程中煤体的温度变化也印证了煤吸附瓦斯放热和解吸瓦斯吸热这一物理现象。
In order to ensure the better effect of coal and gas outburst simulation experiment, aiming at shortages of originally developed simulation test platform, the outburst mould and its additional coal forming device have been improved and developed. Using the technologies of ring direction and surface sealing, etc., omnidirectional sealing, good sealing result for a long time under 2 MPa gas pressure is obtained. With three groups of different circular outburst port diameters, different outburst port experiments of coal and gas outburst simulation under non-replace outburst mould can be conducted, which is economical and practical. Depending on connection between existing temperature, pressure sensors and its additional test control software, real-time monitoring of change law of coal temperature and gas pressure in the process of outburst can be realized conveniently. The separated coal sample molding equipment can add the preconcerted compacting pressure accurately; and it is well established for its flexible operations. The simulation tests carried out by the improved coal and gas outburst simulation test device indicate that there are threshold values of gas pressure and outburst aperture which affect coal and gas outburst occurring or not. When they are greater than the threshold values, the outburst intensity will increase with the increase of the gas pressure or outburst aperture. As the power of outburst, the gas pressure has a certain porphyrization effect on the outburst coal powders. In addition, the temperature change of coal body during coal and gas outburst process has also verified that it is thermopositive when coal absorbs gas, while it is decalescent with releasing gas.