STUDY ON HEAT EXTRACTION PERFORMANCE OF ENHANCED GEOTHERMAL SYSTEMS （EGS） BASED ON MC-DFN SIMULATION

Wang Junchao; Li Chengyu; Li Xinxin

doi:10.19912/j.0254-0096.tynxb.2023-1848

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Acta Energiae Solaris Sinica ›› 2025, Vol. 46 ›› Issue (3) : 91-99. DOI: 10.19912/j.0254-0096.tynxb.2023-1848

STUDY ON HEAT EXTRACTION PERFORMANCE OF ENHANCED GEOTHERMAL SYSTEMS （EGS） BASED ON MC-DFN SIMULATION

Wang Junchao¹, Li Chengyu², Li Xinxin¹

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Abstract

This study proposes a simulation method of geothermal extraction based on the Monte Carlo-discrete fracture network （MC-DFN） model. It investigates the effects of fracture density, inclination angle, and trace lengths on heat extraction performance and analyze key influencing factors. The results reveal that excessively low or high fracture geometry parameters are detrimental to heat extraction. Optimal parameter combinations include a fracture density of 0.003 bars/m², two sets of fractures with inclination angles of 30° and 120°, and trace lengths ranging from 36.55 m to 43.77 m. The sensitivity of fracture geometry parameters to heat extraction follows the order： fracture length > density > inclination angle.

Key words

geothermal energy / discrete fracture network / finite element method / geometric parameter / heat extraction performance / Monte Carlo simulation

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Wang Junchao, Li Chengyu, Li Xinxin. STUDY ON HEAT EXTRACTION PERFORMANCE OF ENHANCED GEOTHERMAL SYSTEMS （EGS） BASED ON MC-DFN SIMULATION[J]. Acta Energiae Solaris Sinica. 2025, 46(3): 91-99 https://doi.org/10.19912/j.0254-0096.tynxb.2023-1848

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