Open Access

ARTICLE

Analysis of Fluid Flow and Optimization of Tubing Depth in Deep Shale Gas Wells

Sheng Ju, Jie Liu^*

School of Petroleum Engineering, Yangtze University, Wuhan, 430100, China

* Corresponding Author: Jie Liu. Email:

Fluid Dynamics & Materials Processing 2025, 21(3), 529-542. https://doi.org/10.32604/fdmp.2024.057535

Received 20 August 2024; Accepted 28 November 2024; Issue published 01 April 2025

Abstract

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.

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