Periodic Reporting for period 1 - GEONEAT (Complex Fluids in Fractured Geological Media for Enhanced Heat Transfer)
Reporting period: 2024-03-01 to 2026-02-28
Understanding how fluids and heat move through fractured rocks is essential for many subsurface technologies, including geothermal energy production, groundwater management, underground energy storage and environmental remediation. In fractured geological formations, fluid flow and transport processes are controlled by complex interactions between fracture geometry, fluid properties and heat exchange with the surrounding rock matrix. These processes are difficult to predict using conventional models because natural fractures are highly heterogeneous and often exhibit irregular rough surfaces.
The GEONEAT project addresses these challenges by developing modelling approaches designed to capture the essential interplay between geological heterogeneity, fluid properties, and heat transfer processes in fractured media. In particular, the project investigates how structural heterogeneity, including fracture roughness and network connectivity, interacts with fluid rheology and thermal exchange between fractures and the surrounding rock matrix to control large-scale transport processes. These mechanisms are relevant in many subsurface applications where complex fluids are injected underground and where heat transfer plays a central role.
The overall objective of the project is to improve the predictive capability of models used to describe flow and transport in fractured systems. By combining theoretical analysis, numerical simulations and stochastic modelling approaches, the project investigates how microscopic processes occurring inside fractures can be upscaled to predict macroscopic transport behaviour at larger scales. Particular attention is devoted to the role of complex fluid rheology and to the thermal signatures that such fluids may generate during flow and heat transport in fractured media.
The results are expected to contribute to more reliable modelling tools for geothermal systems, subsurface energy technologies and groundwater resources.
The GEONEAT project addresses these challenges by developing modelling approaches designed to capture the essential interplay between geological heterogeneity, fluid properties, and heat transfer processes in fractured media. In particular, the project investigates how structural heterogeneity, including fracture roughness and network connectivity, interacts with fluid rheology and thermal exchange between fractures and the surrounding rock matrix to control large-scale transport processes. These mechanisms are relevant in many subsurface applications where complex fluids are injected underground and where heat transfer plays a central role.
The overall objective of the project is to improve the predictive capability of models used to describe flow and transport in fractured systems. By combining theoretical analysis, numerical simulations and stochastic modelling approaches, the project investigates how microscopic processes occurring inside fractures can be upscaled to predict macroscopic transport behaviour at larger scales. Particular attention is devoted to the role of complex fluid rheology and to the thermal signatures that such fluids may generate during flow and heat transport in fractured media.
The results are expected to contribute to more reliable modelling tools for geothermal systems, subsurface energy technologies and groundwater resources.
During the reporting period, the project focused on the development of theoretical and numerical models describing flow and transport processes in geological fractures.
A first research activity investigated the flow of complex fluids in rough fractures. Many industrial subsurface operations involve fluids that exhibit non-Newtonian rheology, whose viscosity depends on the applied shear stress. New modelling approaches were developed to analyse how such rheological effects interact with fracture roughness to influence flow patterns and hydraulic transmissivity.
A second line of research addressed transport and dispersion processes within fractures. Numerical and stochastic modelling techniques were used to investigate how velocity variability and channelization inside fractures influence the spreading of heat along fracture networks.
A third research direction focused on heat transport in fractured media. The project analysed how heat carried by flowing fluids exchanges with the surrounding rock matrix and how fracture heterogeneity affects thermal transport processes. Numerical simulations were developed to study these coupled mechanisms.
The research results were disseminated through presentations at major international scientific conferences and workshops and through the preparation of scientific manuscripts submitted to peer-reviewed journals. Early research outcomes were also shared as open-access preprints, and datasets generated during the project were made publicly available through open research repositories such as Zenodo.
A first research activity investigated the flow of complex fluids in rough fractures. Many industrial subsurface operations involve fluids that exhibit non-Newtonian rheology, whose viscosity depends on the applied shear stress. New modelling approaches were developed to analyse how such rheological effects interact with fracture roughness to influence flow patterns and hydraulic transmissivity.
A second line of research addressed transport and dispersion processes within fractures. Numerical and stochastic modelling techniques were used to investigate how velocity variability and channelization inside fractures influence the spreading of heat along fracture networks.
A third research direction focused on heat transport in fractured media. The project analysed how heat carried by flowing fluids exchanges with the surrounding rock matrix and how fracture heterogeneity affects thermal transport processes. Numerical simulations were developed to study these coupled mechanisms.
The research results were disseminated through presentations at major international scientific conferences and workshops and through the preparation of scientific manuscripts submitted to peer-reviewed journals. Early research outcomes were also shared as open-access preprints, and datasets generated during the project were made publicly available through open research repositories such as Zenodo.
The project contributes to advancing the current understanding of flow and transport processes in fractured geological systems.
Traditional models of fractured media often overlook the coupled effects of heterogeneity, complex fluid behaviour, and thermal exchange. GEONEAT develops stochastic modelling approaches that capture the essential mechanisms linking fracture structure, fluid rheology, and heat transport, enabling the analysis of flow localisation and large-scale transport dynamics. These approaches also provide efficient tools for describing transport processes in heterogeneous fractures without requiring fully resolved numerical simulations.
The project also develops stochastic modelling approaches that provide efficient tools for describing transport processes in heterogeneous fractures without requiring fully resolved numerical simulations. These approaches make it possible to analyse large-scale transport behaviour while retaining the influence of key physical mechanisms occurring at smaller scales.
In addition, the project provides new insights into heat transfer between fractures and the surrounding rock matrix. Understanding these mechanisms is crucial for predicting thermal behaviour in geothermal systems and other subsurface energy technologies.
Traditional models of fractured media often overlook the coupled effects of heterogeneity, complex fluid behaviour, and thermal exchange. GEONEAT develops stochastic modelling approaches that capture the essential mechanisms linking fracture structure, fluid rheology, and heat transport, enabling the analysis of flow localisation and large-scale transport dynamics. These approaches also provide efficient tools for describing transport processes in heterogeneous fractures without requiring fully resolved numerical simulations.
The project also develops stochastic modelling approaches that provide efficient tools for describing transport processes in heterogeneous fractures without requiring fully resolved numerical simulations. These approaches make it possible to analyse large-scale transport behaviour while retaining the influence of key physical mechanisms occurring at smaller scales.
In addition, the project provides new insights into heat transfer between fractures and the surrounding rock matrix. Understanding these mechanisms is crucial for predicting thermal behaviour in geothermal systems and other subsurface energy technologies.