Insights into heat transport for thermal oil recovery

Thermal recovery perhaps is the most significant method for enhanced oil recovery (EOR) technique, especially for heavy oil production, which is defined as a progress in which thermal energy is introduced into the subsurface of reservoir for recovering fuels. Study on thermal energy transporting in oil well dominates the application of thermal recovery process. Predictions of the field behavior of the process require an accurate accounting of the thermal energy injected in to reservoir, therefore a number of heat transport analysis work for wellbore, formation and reservoir have been developed to simulate the related temperature for evaluating oil recovery efficiency and improving thermal efficiency of thermal oil recovery. In this paper, some classical and advanced analytical heat transfer models for wellbore, formation and reservoir are reviewed systematically, and the modeling principles for the heat transfer analysis are also introduced in detail. Based on investigation of steady heat transfer of wellbore and formation transient heat conduction, several wellbore fluid temperature models are reviewed, and some analytical solutions for reservoir temperature distribution and thermal efficiency are also summarized with a detailed comparison. Moreover, the summary of key problems for analytical heat transfer method for thermal oil recovery are described and discussed. Finally, the future development and application of heat transfer analysis for thermal oil recovery is also proposed.