A combined aperture model of an enhanced geothermal system using coupled thermo-hydro-mechanical simulation

To date, most existing fracture aperture models are limited to compression-induced closure and shearinduced dilation for the analysis of heat extraction in enhanced geothermal system (EGS) reservoirs. This paper presents a new, fully coupled thermo-hydro-mechanical (THM) model to investigate the combined effect of shear, thermal and compression stresses on fracture aperture alterations during the heat extraction process. A brief analysis determines the underlying mechanisms characterising these coupled THM processes. The results provide insights into the fracture aperture’s transient behaviour during exploitation, which is a crucial factor in optimising thermal energy production in EGS reservoirs.