基于不同压力下煤层气低速渗流的数值分析

Numerical analysis of coalbed methane low-velocity seepage under different pressures

针对低速渗流过程中煤层气在不同压力下渗流的分析,引入了基于质量源项、动量源项和湍流因素的数学模型,利用Ansys-Fluent软件建立了试件物理模型并进行数值计算。结果表明,在低压时煤层气在煤样中渗流的计算结果与实验数据吻合良好,入口压力越大,靠近出口处的等压面间距越小,渗流速度沿轴向逐渐增大,在压力最低出口处速度达到最大值。

Aiming at the flow analysis of coalbed methane with pressure variation in low-velocity seepage process,a mathematical model based on mass source term,momentum source term and turbulence factor was introduced,and a physical model of specimens was established by using anSYs-Fluent software and numerical calculation was carried out.The results show that the calculated results of coalbed methane seepage in coal samples are in good agreement with the experimental data under low pressure.The greater the inlet pressure is,the smaller the isobaric surface spacing near the outlet is,and the seepage velocity increases along the axial direction,reaching the maximum value at the outlet with the lowest pressure.