Abstract:

A technology for reducing the well bore heat transfer loss of heavy oil production well by using gravity heat pipe is proposed. Based on the heat transfer theory of gravity heat pipe and the model of well bore heat transfer, a theoretical model for calculating the heat loss in well bore with gravity heat pipe is established. The mechanism and technological feasibility of reducing well bore heat transfer loss by using gravity heat pipe are analyzed. Research indicates that gravity heat pipe can raise the temperature of fluid in the upper well bore by absorbing the surplus thermal energy of the fluid in the lower well bore without additional energy. At the same time, it can reduce the well bore heat transfer loss and improve the temperature distribution along the well bore. Through this technology, several factors that influence well bore heat transfer loss are analyzed. The result shows that with the increase of down hole temperature, well fluid yield, the gravity heat pipe setting depth, the heat loss of well bore increase. Flow resistance of heavy oil rising in the down hole pipe can be decreased. Then the pumping unit load can be reduced and the goal of heating the well bore liquid with smaller energy can be achieved.

Key words: heavy oil, heat transfer, heat loss, gravity heat pipe, wellbore, emperature distribution