Mathematical Modeling of Heat Transfer and Pressure Drops in the Single- and Dual-Pipe Horizontal Wells

Abstract

In this paper, from the heat transfer mechanisms between perforated horizontal well and formation, the mathematical models for the heat transfer and pressure drops of the horizontal well with different steam injection pipe configurations are developed. All the conventional single-pipe, concentric dual-pipe, and parallel dual-pipe configurations are considered. A correlation is proposed to represent a relationship between the thermophysical properties of the formation and the formation pressure and temperature. Then, using the method of wellbore microcontrol elements and node analysis, the steam injection process in the three different well configurations is numerically investigated. Based on the test data of a parallel dual-pipe horizontal well from an actual oilfield, a steam backflow procedure for the parallel dual-pipe configuration is proposed to confirm the sealed status of a thermal packer. The theoretical investigation plays an important role in the performance evaluation and productivity prediction of horizontal well-based thermal recovery projects. Furthermore, it also sheds some important insights on a steam injection project design with dual-pipe horizontal wells.