Chapter 7: Heat Transfer in Oil and Natural Gas Production Systems

Heat transfer is a natural phenomenon as thermal energy is transported from one medium to another because of their temperature difference. This phenomenon occurs in the oil and gas production system as a hot reservoir fluid mixture enters a wellbore and immediately begins losing heat to the cooler surrounding wellbore and rock as the mixture flows to the surface. The surrounding rock gradually heats up, reducing the temperature difference and the heat transfer between the fluid mixture and the rock. Eventually, for a constant mass flow rate, the earth surrounding the well reaches a steady-state temperature distribution. Furthermore, when the produced hot hydrocarbon mixture enters pipelines and other surface facilities, the fluids continue losing heat to the surrounding environment, such as cold seawater or the ambient environment. Prediction of the fluid temperature in a wellbore and along a pipeline as a function of distance (and time) is necessary not only to determine fluid physical properties required to calculate pressure gradients but also to predict temperature-driven phenomena of flow assurance. These include organic (asphaltene, paraffin, hydrates) and inorganic (scale) material formation and deposition, as well as pipe corrosion.