TY - EJOU
AU - Ju, Sheng
AU - Liu, Jie
TI - Analysis of Fluid Flow and Optimization of Tubing Depth in Deep Shale Gas Wells
T2 - Fluid Dynamics \& Materials Processing
PY - 2025
VL - 21
IS - 3
SN - 1555-2578
AB - As shale gas technology has advanced, the horizontal well fracturing model has seen widespread use, leading to substantial improvements in industrial gas output from shale gas wells. Nevertheless, a swift decline in the productivity of individual wells remains a challenge that must be addressed throughout the development process. In this study, gas wells with two different wellbore trajectory structures are considered, and the OLGA software is exploited to perform transient calculations on various tubing depth models. The results can be articulated as follows. In terms of flow patterns: for the deep well A1 (upward-buckled), slug flow occurs in the Kick-off Point position and above; for the deep well B1 (downward-inclined), slug flow only occurs in the horizontal section. Wells with downward-inclined horizontal sections are more prone to liquid accumulation issues. In terms of comparison to conventional wells, it is shown that deep shale gas wells have longer normal production durations and experience liquid accumulation later than conventional wells. With regard to optimal tubing placement: for well A1 (upward-buckled), it is recommended to place tubing at the Kick-off Point position; for well B1 (downward-inclined), it is recommended to place tubing at the lower heel of the horizontal section. Finally, in terms of production performance: well A1 (upward-buckled) outperforms well B1 (downward-inclined) in terms of production and fluid accumulation. In particular, the deep well A1 is 1.94 times more productive and 1.3 times longer to produce than conventional wells. Deep well B1 is 1.87 times more productive and 1.34 times longer than conventional wells.
KW - Transient calculation; optimal tubing depth; liquid accumulation; gas wells; deep shale gas
DO - 10.32604/fdmp.2024.057535