三轴应力条件下温度对原煤渗流特性影响的实验研究

摘要

利用自主研发的含瓦斯煤热流固耦合三轴伺服渗流装置,测定煤样在不同有效应力、不同瓦斯压力、不同温度条件下的渗透率,探讨不同有效应力和不同瓦斯压力条件下,煤样渗透率与温度的关系.在实验研究的基础上为消除试件个体差异的影响,客观地反映温度对渗透率影响程度的大小,定义温度敏感性系数,进而研究温度对渗透率的影响程度与温度的关系.研究结果表明:(1)当有效应力和瓦斯压力保持恒定时,随着温度的升高,煤样渗透率会逐渐降低,温度敏感性系数逐渐降低,即温度越高,温度对渗透率的影响程度越小；(2)在相同温度条件下,有效应力、瓦斯压力越大,温度敏感性系数越低,温度对渗透率的影响程度越小.%Using the self-developed triaxial servo-controlled seepage equipment for thermo-fluid-solid coupling of coal containing methane, permeability of coal sample under different effective stresses, different gas pressures and different temperature conditions is determined; and the relationship between permeability and temperature under different effective stresses and different gas pressures is concluded. Based on the experiments, in order to eliminate the deviation due to individual difference, a temperature sensitivity coefficient which can objectively reflect the influence of temperature on the permeability of coal samples is proposed. And then the relationship between temperature and effect of temperature on permeability is also studied. The experimental results are shown as follows: (1) When effective stress and gas pressure keep constant, permeability and temperature sensitivity coefficient both decrease with the increasing temperature, which indicates that the higher the temperature is, the less the effect of temperature on permeability is. (2) If the temperature is same, the larger the effective stress and gas pressure are, the lower the temperature sensitivity coefficient is and the less the effect of temperature on permeability is.