Heat Transfer Processes Upscaling in Geoenergy Fields

Abstract

In this work, the approximations to describe the heat transfer processes in oil and geothermal fields are treated as an upscaling problem. The heat transfer processes in these geoenergy systems, which are considered as a saturated porous medium with multiphase flow, is a complex problem. In this geoenergy system, four scales were analyzed and discussed: (1) field scale, (2) macroscopic scale, (3) Darcy scale, and (4) local scale. It was observed that it is possible to identify two semi-scales when the local thermal equilibrium is applied to macroscopic and Darcy scales. For upscaling from a local scale until field scale of the geoenergy system, the volume averaging method was applied. The interpretation of the thermal conductivity associated with the length-scale restriction in each scale is presented.

Keywords::

• boundary region
• geothermal field
• heat transfer
• heterogeneous system
• homogeneous region
• multicomponent flow
• multiphase flow
• oil field
• porous medium
• stratification
• volume averaging method