中文摘要：

考虑煤层气吸附一解吸过程，提出等效基质颗粒模型，将等径颗粒正排列模型与煤层气解吸结合，建立考虑基质收缩的孔渗计算数学模型，与传统的应力敏感公式相结合得到自调节效应下的孔渗计算式。通过给定不同煤阶储层基本参数，计算分析基质收缩和自调节效应条件下不同煤阶储层的孔渗变化规律。结果表明，在相同生产压差条件下，基质收缩对高煤阶储层孔渗变化幅度的影响最大，中煤阶储层次之，低煤阶储层最小。低阶煤层算例计算结果表明该方法具有可行性。

英文摘要：

Equivalent matrix particle model was proposed by considering the process of adsorption-desorption in coal-bed methane. Mathematical models of porosity and permeability were established by considering matrix shrinkage and combining equant-diameter normal-rank model and desorption. Calculation formulas of porosity and permeability under self-regulating effect were obtained by combining traditional stress-sensitive equations. The changes of porosity and permeability were calcu-lated and analyzed in different coal rank reservoirs through variety of basic parameters. The results show that under the same producing pressure drop, the effects of matrix shrinkage on the reservoir porosity and penmeability of high rank coal, midle rank coal and low rank coal are from strong to weak. The feasibility of the method was verified by a low rank reservoir exam-ple.