摘要
对储层较厚的油藏,油井通常采用部分射开的完井方式,当射开厚度较小时,就会出现球形渗流模式。针对这一情况,基于物质平衡原理,建立了考虑二次压力梯度影响的非线性球形渗流物理数学模型。利用变量代换,将渗流模型线性化,求取了不同外边界条件下拉普拉斯空间的解析解,再利用数值反演求取了实空间的解,并编程绘制了井底压力动态特征曲线。根据曲线形态,分析了井底压力动态响应特征,新的非线性渗流特征曲线与常规线性渗流曲线明显不同,非线性渗流模型的压力和压力导数曲线偏离线性渗流模型的曲线,并进行了理论误差分析,结果表明在一定条件下非线性的影响十分强烈,因此,应加强非线性渗流理论的研究。
For bottom water reservoir and the reservoir with a thick oil formation, there exists partial penetration completion well and when the well products the oil flow in the porous media takes on spherical flow. The nonlinear spherical flow modeling with the quadratic gradient term is established based on the mass conservation principle. By variable substitution, the flowequation was linearized, then the Laplace space analytic solution under different external boundaries was obtained and the real space solution was also gotten by use of the numerical inversion, the bottomhole pressure dynamic type curves were drawn up at last. The bottomhole pressure dynamic behavior were analyzed, and it was found that the new nonlinear flow type curves are evidently different from linear flow type curves, the pressure curve and pressure derivative curve of nonlinear flow deviate from those of linear flow. The theoretical error of the pressure and the pressure derivative between the linear and the nonlinear solution were analyzed, and it was also found that the influence of the nonlinearity is very distinct. Therefore the research on nonlinear seepage flow theory should be strengthened.
出处
《水动力学研究与进展（A辑）》
CSCD
北大核心
2011年第3期333-341,共9页
Chinese Journal of Hydrodynamics
基金
国家重大专项"鄂尔多斯盆地大牛地致密低渗气田勘探开发示范工程"(2008ZX05045-005)
关键词
非线性球形流
压力动态特征
模型
二次压力梯度
nonlinear spherical flow
pressure dynamic behavior
modeling
quadratic pressure gradient
