Title: Production model of fractured horizontal wells in shale gas reservoirs considering different gas diffusion mode

Authors: Shuyong Hu; Wenhai Huang; Jiayi Zhang; Daqian Rao; Bingyang Zheng; Tingting Qiu

Addresses: State Key Laboratory of Oil and Gas Reservoir Geology Exploitation Engineering, Southwest Petroleum University, Chengdu, Sichuan, 610500, China ' PetroChina Southwest Oil and Gas Field Company Development Department, Chengdu, Sichuan, 610500, China ' State Key Laboratory of Oil and Gas Reservoir Geology Exploitation Engineering, Southwest Petroleum University, Chengdu, Sichuan, 610500, China ' Zhejiang Oilfield Company, Petro China, Hangzhou, Zhejiang, 310023, China ' Northwest Oilfield Branch of China Petroleum and Chemical Corporation, Urumqi, Xinjiang, 830000, China ' School of Energy Resources, China University of Geosciences (Beijing), Beijing, 100083, China

Abstract: Because of the complexity of the shale gas seepage mechanism, the establishment of a fractured horizontal well model of shale gas reservoirs based on multiple migration mechanisms is helpful to the development of shale gas reservoirs. In this study, different matrix diffusion modes in different regions are considered. The fractured horizontal well model of the shale gas reservoir can be divided into a fracture network region (SRV region) and a shale matrix region. The quasi-steady-state matrix diffusion in the fracture network region is described by Fick's first law, the non-steady diffusion in the matrix region is described by Fick's second law, and seepage of the fracture system is described by Darcy's law. Based on the above ideas, a fractured horizontal well production model of fractured horizontal wells in shale gas reservoir is established. The Laplace transformation, Duhamel principle, and Stehfest numerical inversion are used to solve the mathematical models of seepage flow, and a sensitivity analysis of the dimensionless production curve is performed. [Received: January 22, 2023; Accepted: February 13, 2024]

Keywords: shale gas; fractured horizontal well; seepage mechanism; gas diffusion; seepage model.

DOI: 10.1504/IJOGCT.2025.143028

International Journal of Oil, Gas and Coal Technology, 2025 Vol.37 No.1, pp.1 - 28

Received: 06 Jan 2023
Accepted: 13 Feb 2024
Published online: 02 Dec 2024 *

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