基于应力敏感的天然裂缝性页岩气藏双孔模型解的结构

针对天然裂缝性页岩气藏，研究了3种外边界条件（无穷大、定压、封闭）及内边界条件下的定产量生产问题，并建立了考虑应力敏感性和解析吸附的不稳定渗流的试井分析模型.先对此模型作线性化处理；然后通过摄动法以及利用Laplace变换，求得线性化后的无因次储层压力的Laplace空间精确解；最后根据解的相似结构理论，给出了求解该模型解结构的步骤，并且定义了3种外边界条件下的相似核函数，发现了此模型在3种外边界条件下精确解之间的相似结构.这项研究不仅为编制试井分析软件提供便利, 提高计算效率，而且对页岩气藏渗流理论的研究具有重要意义，也为页岩气藏渗流模型的求解提供了一种新的方法.

Similar Structure of the Solution to the Dual-Porosity Model for Naturally Fractured Shale Gas Reservoirs Based on Stress Sensitivity

For naturally fractured shale gas reservoirs, the problem about fixed output was addressed in 3 outer boundary conditions (infinite boundary, constant pressure and closed boundary) and inner boundary conditions, to build a well test analysis model for unsteady seepage flow in view of stress sensitivity and desorption & adsorption. Firstly, the model was linearized. Secondly, the perturbation method and the Laplace transform were used to get the exact solution of dimensionless reservoir pressure in the Laplace space with the linearized model. Finally, according to the similar structure theory, the steps leading to the similar structure of the solution to this model were presented. In addition, the kernel functions in the 3 outer boundary conditions were defined and it was found that a similar structure existed among the exact solutions of this model in the 3 outer boundary conditions. The work not only facilitates the development of well test analysis software with higher calculation efficiency, but also helps a lot in the investigation of shale gas seepage mechanisms, making a new method for the solution of the shale gas seepage model.