The thermal behavior of a deepwater well was simulated using an existing mathematical model in which a rigorous flow-pattern based multiphase flow model was employed to predict the pressure drop of the hydrocarbon stream. The heat transfer model relied on the energy equation for the hydrocarbon mixture and on a radial thermal resistance network between the wellbore and the formation. Different annulus convection and thermal formation models were evaluated.
Production pressure and temperature results were compared with field data and with a commercial software package, showing good agreement with both. The model was able to capture important quantitative phenomena associated with the wellbore heat transmission (e.g., lithologic column and annulus fluid type). The simulations showed that for short production times the heat transfer to the formation was significantly influenced by the wellbore thermal resistances, namely the cement sheaths and the nitrogen present in the production annulus. As the production time increased, the formation became the dominant thermal resistance. The mathematical model was capable of handling real production scenarios, such as the impact of a watercut time-dependent behavior on the temperature distribution in the wellbore.