煤粒瓦斯扩散的数值解法

发布时间：2018-09-10 15:38

【摘要】：针对煤粒瓦斯扩散的解析解法存在的问题,推导了单孔扩散模型的数值解表达式,提出煤粒瓦斯扩散的数值解法,同时对比分析了解析解与数值解结果的差异性。分析认为:解析解法仅适用于分析定压扩散实验和球形煤粒,其采用的线性吸附假设也与真实瓦斯吸附规律相违背;数值解法考虑了瓦斯吸附常数、煤体孔隙率和温度等真实煤体参数与外界条件,因此具备一定的优越性;在相同瓦斯扩散系数条件下,解析解法计算的煤层瓦斯扩散速率相较数值解较小;如果通过煤粒瓦斯扩散实验结果反算瓦斯扩散系数,传统的解析解法可能会高估煤层的真实瓦斯扩散系数。
[Abstract]:In view of the problems existing in the analytical solution of coal particle gas diffusion, the numerical solution expression of the single hole diffusion model is derived, and the numerical solution of coal particle gas diffusion is put forward, and the difference between the analytical solution and the numerical solution is compared and analyzed. It is considered that the analytical method is only suitable for the analysis of constant pressure diffusion experiments and spherical coal particles, and the linear adsorption assumption is also contrary to the true law of gas adsorption, and the gas adsorption constant is taken into account in the numerical solution. The real coal body parameters such as porosity and temperature of coal body and external conditions have certain advantages, under the condition of the same gas diffusion coefficient, the gas diffusion rate calculated by analytic method is smaller than that calculated by numerical method. If the gas diffusion coefficient is calculated back by the experimental results of coal particle gas diffusion, the real gas diffusion coefficient of coal seam may be overestimated by the traditional analytical method.
【作者单位】：煤炭科学技术研究院有限公司安全分院;煤炭科学研究总院煤炭资源高效开采和洁净利用国家重点实验室;
【基金】：国家自然科学基金资助项目(51604153) 北京市自然科学基金资助项目(2164057) 煤矿区煤层气抽采利用关键技术与装备重大专项资助项目(2016ZX05045006-006)
【分类号】：TD712

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