Modeling Simplified Fracture Networks in Enhanced Geothermal Systems Using a Phase-Field Model for Crack Nucleation
Iran Hernandez Imbert, Duke University
Enhanced Geothermal Systems (EGS) are a promising area for sustainable energy, as they take advantage of naturally-occurring underground heat to generate power. Central to EGS functionality is the creation and maintenance of fracture networks within hot rock formations. These networks enable the circulation of a working fluid, which heats up as it travels through the fractures and is then extracted in a production well. Understanding the initiation and propagation of these fractures is critical for optimizing EGS efficiency and ensuring long-term sustainability. Given the scale of these underground systems and the uncertainties around the response of hot rock formations, EGS benefit greatly from computational modeling and analysis. In this project, the MOOSE framework is used to develop finite-element discretizations of the rock formations and the fracture networks. Here, the fracture networks are represented with a regularized phase-field model that enables the simulation of geometrically complex crack nucleation and propagation. The areas presented in this poster will focus on modelling a simplified fracture geometry as a proof-of-concept in the use of a recent phase-field model for crack nucleation based on a material strength envelope. The results highlight the areas of resultant fracture and offer an illustration for how these models can be used to determine and adjust necessary parameters for efficient EGS performance.