This study investigates the thermo-hydro-mechanical (THM) coupling impacts on seepage and heat transfer characteristics to enhance the efficient utilization of hot dry rock resources in the Guanzhong Basin. A computational model of thermo-hydro-mechanical three-field coupling for an enhanced geothermal system is developed based on the geological context and rock thermophysical properties of the Huazhou-Huayin target area in the Guanzhong Basin. The effects of differential pressure during injection and production, injection temperature, and well configuration on the reservoir stress field, permeability variations, temperature distribution, and heat recovery efficiency of the system are carefully simulated and analyzed. Simulations indicate that increasing the injection–production pressure differential from ±1 MPa to ±7 MPa dramatically enhances heat recovery, yielding a fivefold increase in the extraction rate and an 11.54-fold rise in cumulative heat production. Conversely, this aggressive approach severely impacts long-term sustainability, accelerating thermal breakthrough and drastically cutting the operational lifespan by 93.30%. Lowering the injection temperature from 60 °C to 20 °C yields a 24.14% enhancement in heat output over the same duration, together with a 24.14% increase in the geothermal extraction rate. Increasing the number of injection–production wells from one to two broadens the heat extraction range and improves system heat production by 35.82%, concurrently diminishing lifespan by 39.50%. This work possesses theoretical importance for the progression of hot dry rock initiatives similar to those in the Guanzhong Basin and other geological settings.
Zhang et al. (Fri,) studied this question.