摘要
基于流固耦合力学理论和热力学理论 ,建立了变温条件下弹塑性油藏中多相渗流的数学模型。假设油藏中岩石固相骨架是可变形的 ,孔隙流体压力、温度场的变化将导致油藏内有效应力发生变化 ,从而导致岩石骨架变形 ,这种变形反过来又影响多相流体的渗流。建立变温条件下完全耦合的流体渗流方程和固相变形方程 ,它们互不独立 ,不能单独求解 ,只能联立求解。假设岩石骨架具有弹塑性 ,采用了建立在屈服准则基础上的弹塑性本构模型。针对某些温度场变化大的油藏 ,如注热水、注蒸汽开采的油藏 ,充分考虑了温度场变化对岩石骨架变形和流体渗流的影响。将“热载荷”概念引入固相变形方程来描述这种影响 ,并给出了热载荷的求法。交替运用有限差分和有限元法给出变温条件下的耦合数值模拟方法。所建立的数值模拟方法可作为编制变温流固耦合软件的依据。参
The mathematical mo del of multiphase flow in an elastopla stic deforming oil reservoir with the variable temperature distribution is devel oped based on the theory of fluid solid interaction mechanics and thermodynamic s . The solid skeleton of the oil reservoir is assumed to have the characteristics of deformation and the changes of the pore pressure and the temperature distrib ution result in changes of effective stresses acting in the oil reservoir and in the deformation of the solid skeleton. Conversely, deformation of the solid ske leton affects the seepage of the multiphase flow. In this paper, fully coupled s eepage equations and deformation equations are developed in consideration of tra nsformation temperature. These equations are not independent and can't be solved divisionally. The solid skeleton is assumed to have an elastoplastic behavior a nd an elastoplastic constitutive model based on yield function is utilized. The variation of the deformation of the solid skeleton and the seepage of the multip hase derived from the change of temperature distribution is fully considered in a reservoir with violent transformation temperature such as a oil reservoir in w hich hot water or steam is injected. The concept 'thermal load' is added in de formation equations to describe this thermodynamic process and the solving for' thermal load'is presented. The approach of coupled numerical simulation in whic h finite difference method and finite element method are used alternately is pre sented.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2001年第6期68-72,共5页
Petroleum Exploration and Development
关键词
弹塑性油藏
变温条件
多相渗流
流固耦合
数学模型
数值模拟
Elastoplasticity, Oil and gas res ervoir, Temperature field, Fluid solid coupling, Mathematical model, Numerical simulation
