Study of Gas–Water Two-Phase Flow Characteristics During Water Invasion in Large Bottom-Water Gas Reservoirs Based on Long-Core Dynamic Simulation
Year: 2025
Type: article
Abstract: In this study, we investigated the influence of water invasion velocity on gas–water permeability in bottom-water gas reservoirs. We conducted simultaneous core water invasion experiments under actual reservoir conditions, systematically examining varied permeability cores and multiple influx velocities. Two data processing methods were comparatively validated, analyzing gas–water relative permeability curves, fractional flow curves, and injection volume–recovery efficiency relationships. The results indicate that under HTHP (high-temperature, high-pressure) conditions, gas relative permeability declines faster, while water relative permeability increases more significantly. NMR imaging revealed that water preferentially invades smaller pores, accelerating gas–water flow before entering larger pores, leading to a rapid increase in water relative permeability. Long-core experiments unveiled a waterfront “stepwise advance” and localized water channeling due to heterogeneity, which were not observed in short-core tests. Water influx velocity critically influences fractional flow curves: high velocities cause rapid post-breakthrough water cut increase, easily inducing fast water breakthrough and coning, whereas low velocities promote a uniform frontal advance. HTHP (high-temperature, high-pressure) long-core flooding experiments more accurately reflect actual reservoir water influx dynamics, offering key insights for optimizing development strategies, delaying water influx, and enhancing recovery efficiency.
Source: Processes
DOI: 10.3390/pr13092761
Authors: Zhengyi Zhao, Changquan Wang, Shijing Xu, Lihong Shi
Language: English
Subfield: Ocean Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,896
Funder: Yangtze University
OpenAlex ID: W4413833255