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

doi: 10.21656/1000-0887.370190

¹Institute of Applied Mathematics, School of Science, Xihua University, Chengdu 610039, P.R.China;²Beijing Dongrunke Petroleum Technology Co., Ltd., Beijing 100029, P.R.China

Received Date: 2016-06-15
Rev Recd Date: 2016-07-06
Publish Date: 2017-02-15

Abstract

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.
- stress sensitivity,
- naturally fractured shale gas reservoir,
- desorption & adsorption,
- kernel function,
- similar structure

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