| Title | Numerical Characterization of Heat Transfer Properties in Fracture Networks with Dead-Ends |
|---|---|
| Authors | Lisa Maria Ringel, Yves Méheust, Maria Klepikova |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | Understanding heat transport in fractured rock formations is crucial for various geothermal applications, including predicting the production temperature and production life in enhanced geothermal systems, optimizing storage and recovery of thermal energy in fractured rocks, and utilizing heat as a tracer to infer the hydraulic and thermal properties of fractured sites. This study focuses on characterizing coupled thermal-hydraulic (TH) processes that govern heat transfer in such environments. Fluid flow occurs primarily in the fracture network, where the permeability and connectivity of the fractures control the flow behavior. This flow facilitates convective heat transfer between the fluid and the adjacent rock, which interacts with the conductive heat transfer driven by temperature gradients. We apply numerical simulations to investigate TH processes and the heat exchange between the fluid and rock matrix at the intersection of fractures, with particular attention to the influence of dead-ended fractures or T-intersections. The numerical model distinguishes two domains: a fluid domain representing the fractures and a solid domain for the impermeable rock matrix. The fluid domain is described by the conservation equations for mass, momentum, and energy, whereas the rock matrix is governed by heat conduction. We systematically investigate the impact of fracture aperture, matrix thermal conductivity, intersection geometry, and fracture surface roughness on the thermal breakthrough behavior, the progression of the thermal front, and the evolution of the heat flux across fracture-matrix interfaces. The results underscore the significance of fracture network properties in describing heat transport within fractured geothermal reservoirs. |