A new numerical approach of coupled modeling for solid deformation and gas leak flow in multi-coal-seams

From the viewpoint of interaction mechanics for solid and gas, a coupled mathematical model was presented for solid coal/rock deformation and gas leak flow in parallel deformable coal seams. Numerical solutions using the SIP (Strong Implicit Proce- dure) method to the coupled mathematical model for double parallel coal seams were also developed in detail. Numerical simulations for the prediction of the safety range using protection layer mining were performed with experimental data from a mine with potential danger of coal/gas outbursts. Analyses show that the numerical simulation results are consistent with the measured data in situ.

Numerical simulation of coal-bed methane transfer with finite element method

The mathematical model and the numerical simulation for the transfer of coal bed methane were established based on the combination of the porous flow theory and elastic plastic mechanics theory and the numerical solution was given, together with the consideration of the fluid solid interaction between the coal bed gas and coal framework. Then the dispersion for the equation of gas porous flow and coal seam distortion was carried out and the functional analysis equation was obtained. Finally, the coupling solution was educed and calculated by finite element method(FEM) on a model example.

卸压增透下底板定向拦截钻孔瓦斯抽采模拟研究

杜儿坪矿68311工作面在回采时下邻近层瓦斯涌入量较多,为此采用在底板打定向拦截钻孔并进行瓦斯抽采的方法。为体现工作面回采对底板造成的卸压增透以及合理设计瓦斯抽采参数,首先使用FLAC3D模拟工作面回采不同距离下的底板有效应力变化,将其转换为渗透率变化并导入至COMSOL中,再通过建立流-固耦合数学模型完成不同抽采参数下的瓦斯抽采模拟。研究结果表明:工作面回采距离越大,卸压增透效果越好;钻孔层位由6 m降低至2 m,瓦斯抽采有效半径提高15.10%;钻孔直径由φ60 mm增加至φ120 mm,瓦斯抽采有效半径增加15.03%。