ABSTRACT
Knowledge of fluid flow temperature along the wellbore can be useful for a realistic calculation of the total heat production in geothermal wells. Therefore, wellbore modeling is an important part of the characterization of geothermal wells and predicting their future behavior. This study describes the dynamic transport of transient heat and fluid dynamic transport inside a geothermal well and also heat loss in the surrounding rocks. The objective of this investigation is to accurately predict temperature and pressure variations within the producing well GPK2 of the geothermal site Soultz-sous-Forêts. The temperature effect of possible leakage zones in the reservoir section of the production casing was also considered. A single-phase flow modeling was carried out using Comsol software. Our study highlights that the properties of the flow (well flow rates for steady and unsteady flow), of the fluid (density, viscosity, chemical composition), and the well (diameter, length, thermal properties of environments) are parameters, which directly influence the pressure and temperature profiles of the well. A sensitivity study has been carried out to demonstrate the role that these parameters play in the heat transport occurring in this well. According to our simulated results, during the flow of hot water in GPK2 well the production temperature of water decreases by dozen degrees of its downhole temperature. It is also shown that the leakage zone affects the temperature, decreasing it at least by 1–2°C.
Acknowledgements
The authors would like to thank ES-Géothermie, the Soultz-sous-Forêts site owner, EEIG Exploitation Minière de la Chaleur for data access and the EU-funded H2020 project MEET (GA 792037).
Disclosure statement
No potential conflict of interest was reported by the authors.
Additional information
Notes on contributors
Gaukhar Akhmetova
Dr. Gaukhar Akhmetova, currently seeking new opportunities. She received her PhD in Energy and Mechanics from University of Lorraine. Her main research interest in reservoir engineering, fluid dynamics and geothermal reservoirs.
Irina Panfilova
Dr. Irina Panfilova, Associate professor HDR, National school of geology (ENSG), University of Lorraine, Vandœuvre-lès-Nancy, France. She received her PhD in multiphase flow in porous media from INPL Nancy and HDR degree in ”Mechanics and Energetics” from University of Lorraine. Her main research interest in the field of fluid mechanics, reservoir engineering and gas-liquid flows with phase transitions in porous media.
Sylvain Bourlange
Dr. Sylvain Bourlange, is Associate professor at University of Lorraine, Laboratoire CNRS GeoRessources (UMR 7359), Vandœuvre-lès-Nancy, France. He received his PhD in geodynamics and earth physics from Paris-Sud University. His main research interests are fluids in tectonics, structural geology and geodynamics.
Antonio Pereira
Dr. Antonio Pereira, is Associate professor at the University of Lorraine, Vandœuvre-lès-Nancy, France. He received his PhD in Statistical Physics and Nonlinear Phenomena from Imperial College London. His main research interest in the field of fluid mechanics, multi-phase interactions, diffuse interface method and numerical modelling.