Overview of Wellbore Fluid Flow and Heat Transfer Modeling with Applications in the Oil Industry

M. Bahonar, J. Azaiez, and Z. Chen


Wellbore fluid flow and heat transfer modeling has numerous applications in the petroleum industry and has increasingly become more important as more sophisticated injection, production, monitoring, and testing operations are applied to wells and reservoirs. Nowadays, wells often involve more than the traditional single production or injection tubing string in the wellbore [1]. In particular, co-production and co-injection of fluids through tubing and annulus and through more than one independent tubing string in the same wellbore are common in oilfields [1]. Additionally, using multilateral wells has become frequent in the oil industry. In fact, wellbore is the only mean of communication between surface and underground and therefore, it should be modeled precisely in order to be able to design, manage, and optimize required operations. However, the multiphase nature of the flow inside the wellbore, the complex heat transfer mechanisms between the wellbore and the surrounding medium (specifically in thermal operations), and the unsteady state of the processes make the entire system intricately coupled and extremely difficult to model and analyze. Since fluid properties are usually pressure and temperature sensitive, computations of the pressure and temperature profiles are influenced by each other and thus very important in the wellbore. Therefore, transport processes in the wellbore/reservoir system are highly coupled, and any changes or perturbations in any of them have direct effects on the others. In this article, some of the applications of wellbore flow modeling will first be outlined. This will be followed by a short history of wellbore fluid flow and heat transfer modeling. Finally, a numerical non-isothermal two-phase wellbore model that can simulate downward flow of a steam and water mixture in the wellbore is briefly discussed (for more details on this last part, please consult reference [2]).