Thermodynamic analysis of water boiling in presence of a non-condensable gas, the carbon dioxide (co2) : application to geothermal flows in wellbores

Abstract

W1D is a wellbore simulator developed as part of the GEOTREF (GEOThermal energy in Fractured REservoirs) project. A coupled system of equations ensuring mass, momentum and heat balance with appropriate set of models and correlations is resolved to describe multi-component and multi-phase flow along the well axis. The simulator is designed to be effective as a practical tool in the monitoring of geothermal systems. In the present work, the code is used to carry out physical investigations on the water boiling occurring alongside the degassing of a non-condensable gas, the carbon dioxide (CO2). For high Reynolds flows in geothermal wellbores, it is illustrated that a thermodynamical approach with appropriate assumptions is able to accurately capture the effect of local physical mechanisms (such as the interfacial mass transfer resistance) on the global dynamic (partitioning of CO2 in liquid and gas phases).