FLUID-FLOW AND HEAT-FLOW IN DEFORMABLE FRACTURED POROUS-MEDIA

Analtyical solutions based on a porothermomechanical formulation for double-porosity media have been presented. Complete coupling is ensured among fluid flow, heat flow, and solid deformation in the conservation of momentum. Partial coupling between fluid flow and deformation is justified for the problems solved in infinite media or media with a relatively distant boundary. Full decoupling in heat flow is implemented for the convenience of obtaining the analytical solutions sequentially and is justifiable for the temperature distribution anywhere but in close proximity of the loading. This coupling can be readily restored through numerical means. In comparison with previous publications, the model presented provides more realistic characterization of reservoir storage changes in the fluid flow. The double-porosity behaviors of fractured porous media for both fluid flow and heat flow have been identified. The corresponding effect due to thermal and fluid pressure changes on solid deformation, particularly in the vicinity of the flow and/or heat source(s), has been emphasized. The significant impact of thermal loading and reservoir mechanical properties on the reservoir porothermomechanical environment has been demonstrated.