摘要
为分析层状双孔介质储层水平井的压力动态特征,采用不稳定渗流理论和层状介质波动方程研究了该类复杂储层水平井的不稳定渗流问题.基于Laplace变换和双重Fourier余弦变换,首先求得点汇问题的Green函数,然后通过叠加原理和双重Fourier逆变换推导出Laplace空间多层双孔介质储层水平井的压力响应,并基于反射透射方法(RTM)提出了相应的压力求解方法.以两层储层为例,计算了垂向水平渗透率比值、储层厚度、窜流系数和储容比对水平井压力的影响.结果表明,多层储层的层间窜流导致流动早中期水平井压力导数曲线呈现不同的台阶,不考虑层间窜流的多层合采模型的压降比窜流模型大,两者具有明显不同的曲线形态;水平井所在层厚度越小,储容比越大,导数曲线层间窜流特征越完整;窜流系数对导数曲线上"凹子"出现的时间和深度都有影响.
In order to investigate the pressure dynamic characteristics of horizontal wells in layered dual-porosity reservoir,the unstable seepage problem of horizontal wells were studied using the unstable seepage theory and layer medium wave function.Based on Laplace transform and double Fourier cosine transform,Green function of sink solution was firstly obtained,and then the Laplace solution of pressure response of horizontal well was got by the superposition principle and double inverse Fourier transform.Finally,a new method to solve this problem was presented based on reflection and transmission method（RTM）.Taking two layers of reservoir as a case in point,this study calculated and analyzed the influence of following factors on the pressure of horizontal well,including ratio between vertical and horizontal seepage,reservoir thickness,interporosity flow coefficient,storage ratio.The results show that different stages in pressure derivative curve in early and middle phase occur because of inter-layer crossflow in multilayer reservoir.In addition,the pressure drop of commingling production model with little regard to inter-layer crossflow is larger than that of inter-layer crossflow model,both have a significantly different curve shapes.The smaller thickness of the layer where the horizontal well is located,the bigger ratio of storage is,which leads to more complete features of inter-layer crossflow in derivative curves;interporosity flow coefficient has an impact on both occurring time and depth of the concave shape in derivative curves.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2013年第3期436-443,共8页
Journal of China University of Mining & Technology
基金
国家科技重大专项(2011ZX05010-002)
关键词
多层储层
双孔介质
水平井
层间窜流
GREEN函数
multilayered reservoir
double porosity
horizontal well
inter-layer crossflow
Green function
作者简介
通信作者：杨超（1986-），男，山东省青州市人，博士研究生，从事油气田开发和数值模拟方面的研究E-mail：yangcha02010phd@163．com.Tel：010—83592242
