The mechanism of drainage gas recovery and structure optimization of an internal vortex tool in a horizontal well

Abstract

Effective drainage gas recovery technology is the key to solving the problem of the liquid loading of gas well and of enhanced gas recovery. An internal vortex tool is designed for solving the problem of liquid loading in horizontal wells. This study conducted a computational fluid dynamics analysis the efficiency of the drainage gas recovery of the tool in the horizontal well, to optimize the structure of the tool. The results show that most of the liquid film flows along the pipe wall in the internal vortex tool, and the gas flows through the central area of the pipe at a high speed with fog. The internal vortex tool can increase the gas phase velocity and separate the gas and liquid. The structural parameters of the internal vortex tool for minimum pressure loss and the maximum drainage efficiency is the same diameter as the tubing and casing for the runner diameter, 42.8° for the swirl angle, 8 mm for the helix height, 6 mm for helix width and 4 for the number of lead. The study on the flowing of a gas liquid swirling flow in the internal vortex tool proves the feasibility of its application in horizontal wells. It can provide theoretical guidance and a practical basis for efficient liquid loading using the internal vortex tool in the future.