Interplay of heat transport and fracture aperture in fractured reservoirs

In this study, the interaction among thermal-hydraulic-mechanical (THM) processes in fractured reservoirs is investigated by means of numerical experiments. Particularly, the impact of fracture geometry, the injection rate and rock matrix permeability on heat transport in such reservoirs is studied.

To do this, a fully coupled thermal-hydraulic-mechanical finite element is utilised to consider non-isothermal flow through the rock matrix and fractures subjected to mechanical deformation. The resulting temperature field is observed for different scenarios considering a doublet system in which cold fluid is injected into an injection well, and hot fluid is extracted from the production well.

The simulations strongly support that in fractured systems depending on fracture density and matrix permeability, the arrival time of the cold front and the extent of the cold plume vary.