Time-dependent model for two-phase flow in ultra-high water-cut reservoirs:Time-varying permeability and relative permeability  

作　　者：Shao-Chun Wang Na Zhang Zhi-Hao Tang Xue-Fei Zou Qian Sun Wei Liu 

机构地区：[1]College of Energy Resources,Chengdu University of Technology,Chengdu,610059,Sichuan,China [2]College of Petroleum Engineering,Shandong Institute of Petroleum and Chemical Technology,Dongying,257061,Shandong,China

出　　处：《Petroleum Science》2024年第4期2536-2553,共18页石油科学（英文版）

基　　金：supported by Research project of Shengli Oifield Exploration and Development Research Institute (Grant No.30200018-21-ZC0613-0125)。

摘　　要：For the ultra-high water-cut reservoirs,after long-term water injection exploitation,the physical properties of the reservoir change and the heterogeneity of the reservoir becomes increasingly severe,which further aggravates the spatial difference of the flow field.In this study,the displacement experiments were employed to investigate the variations in core permeability,porosity,and relative permeability after a large amount of water injection.A relative permeability endpoint model was proposed by utilizing the alternating conditional expectation(ACE)transformation to describe the variation in relative permeability based on the experimental data.Based on the time dependent models for permeability and relative permeability,the traditional oil-water two-phase model was improved and discretized using the mimetic finite difference method(MFD).The two cases were launched to confirm the validation of the proposed model.The impact of time-varying physical features on reservoir production performance was studied in a real water flooding reservoir.The experimental results indicate that the overall relative permeability curve shifts to the right as water injection increases.This shift corresponds to a transition towards a more hydrophilic wettability and a decrease in residual oil saturation.The endpoint model demonstrates excellent accuracy and can be applied to time-varying simulations of reservoir physics.The impact of variations in permeability and relative permeability on the reservoir production performance yields two distinct outcomes.The time-varying permeability of the reservoir results in intensified water channeling and poor development effects.On the other hand,the time-varying relative permeability enhances the oil phase seepage capacity,facilitating oil displacement.The comprehensive time-varying behavior is the result of the combined influence of these two parameters,which closely resemble the actual conditions observed in oil field exploitation.The time-varying simulation technique of reservoir physical pr

关 键 词：Mimetic finite difference Water flooding reservoir Time-varying physical properties Numerical simulation 

分 类 号：TE311[石油与天然气工程—油气田开发工程]