山西沁水盆地中-南部煤储层渗透率物理模拟与数值模拟

通过对山西沁水盆地中南部上主煤层宏观裂隙观测,力学参数测量和应力渗透率实验,分别建立了裂隙面密度、裂隙产状、裂隙宽度与煤储层渗透率之间的预测数学模型;利用FLAC—3D软件,模拟了该区上主煤层内现代地应力状态,结合煤层气试井渗透率资料,构建了应力与渗透率之间关系预测的数学模型,并对该区上主煤层渗透率进行了全面预测。通过吸附膨胀实验,揭示了各煤类煤基质的收缩特征,构建了有效应力、煤基质收缩与渗透率之间的耦合数学模型,并对煤层气开发过程中渗透率动态变化进行了数值模拟。

PHYSICAL AND NUMERICAL SIMULATIONS OF PERMEABILITY OF COAL RESERVOIRS IN CENTRAL AND SOUTHERN PART OF THE QINSHUI BASIN, SHANXI

Based on macrofracture observation, measurements of mechanic parameter and stress permeability experiment of the upper main coal reservoirs in the central and southern part of the Qinshui Basin in Shanxi Province, the mathematical models for predicting the relationship between permeability and face densities, occurrence and width of fractures were established, respectively. The recently crustal stress situation was simulated with FLAC 3D software, the mathematical model for predicting the relationship between the recently crustal stress and permeability was also established integrating the data of coal bed methane testing permeability, and permeability of the upper main coal reservoirs in the studied region was systematically predicted. The characteristics of coal matrix shrinkage in various coal ranks were revealed by means of adsorption/swelling experiment, the coupling mathematical model among effective stress effect, coal matrix shrinkage effect and permeability was established, and the dynamic change of permeability was simulated during the coalbed methane development.