Modeling Thermal Breakthrough in Sedimentary Geothermal System, Using COMSOL Multiphysics

Abstract

It is known that premature thermal breakthrough in the production well and cooling due to injection of cold water into a geothermal reservoir can degrade the quality of the reservoir operation. As the heat and mass transfer in the reservoir depends on the internal features of the reservoir and the interfacial features of surrounding rocks, there has been an increased effort to model geothermal reservoirs with detailed pore structures. In this work, the effect of heat extraction on advancement of cold front in both reservoir and surrounding host rock will be discussed. A segment of the deep sedimentary basin consists of high permeable fracture in a region with high temperature gradient is modeled. The influence of variable permeability on heat transfer within reservoir will be numerically investigated. COMSOL Multiphysics is used to generate models with different permeability distribution for host rock.