TITLE:
Numerical Simulation Considering Non-Equilibrium Phase Change Volatile Oil Reservoir: A Case Study of Wenchang 8-3 Oil Reservoir
AUTHORS:
Haichun Xu
KEYWORDS:
Volatile Reservoir, Production Characteristic, Non-Equilibrium Phase Change, Numerical Simulation
JOURNAL NAME:
International Journal of Geosciences,
Vol.12 No.9,
September
26,
2021
ABSTRACT: As a typical
volatile oil reservoir, the actual production characteristics of
Wenchang 8-3 reservoir are inconsistent with the results of traditional phase
equilibrium experiments. The conventional isothermal instantaneous phase
equilibrium theory cannot meet the production performance or numerical simulation
analysis requirements of this type of reservoir. The thermodynamic properties
of volatile oil reservoirs are like those of condensate gas reservoirs. As the
formation pressure drops below the dew point pressure during the mining
process, the balance between the liquid phase and the gas phase is not
completed instantaneously. Based on the non-equilibrium phase recovery
treatment method of the condensate gas reservoir, the phase behavior change
curve of the A4h well of Wenchang 8-3 oil reservoir recovered from the
saturation pressure to three different pressures is analyzed. The accuracy of
the numerical simulation results with or without non-equilibrium phase
transition is compared. The results show that the non-equilibrium phase change
has a great impact on the production performance of volatile oil reservoirs; the numerical simulation results considering the
non-equilibrium phase transition are in good agreement with the actual
production performance of a single well and can better reflect the actual situation
of this type of reservoir. Therefore, considering the effects of
non-equilibrium phase transitions has important guiding significance for the
dynamic analysis of volatile oil reservoirs, numerical simulation, and the
formulation of development management strategies.