The Flow Model With The Quadratic Pressure Gradient Term And The Type Curves Of Well Testing For Fractured-vuggy Triple-Medium Reservoir
- 作者：Renshi NieYonglu JiaYongheng WangBin Liu
- 会议时间：2007-10-20
- 关键词：裂缝型油藏 ; 二次压力梯度 ; 非达西渗流模型 ; 非定常流 ; 偏微分流方程
- 作者单位：Renshi Nie,Yonglu Jia(Southwest Petroleum University)Yongheng Wang(Huabei Petroleum Administration of SINOPEC)Bin Liu(Northeast Sichuan Gas Field,Jing Tan,Liaohe Petroleum Exploration Bureau of CNPC)
- 母体文献：2007年油气藏地质及开发工程国家重点实验室第四次国际学术会议论文集
- 会议名称：2007年油气藏地质及开发工程国家重点实验室第四次国际学术会议
- 会议地点：成都
- 主办单位：中国石油学会
- 语种：chi
摘要
This paper aims at the unconventional triple porosity reservoir with fracture and vugs, according to the basic percolation principle the non-linear testing flow model with the quadratic pressure gradient term has been established, for the pseudo-steady and the unsteady interporosity flow of the matrix and vugs to fracture. For the pseudo-steady interporosity flow model, by use of Douglas-Jones prediction- correction numerical method, the partial differential flow equation has been solved. For the unsteady interporosity flow model, by use of the variable substitution, linearizing the governing equation, the model has been solved, then obtained the Laplace space analytic solution and procured the real space solution by use of the Stehfest numerical inversion. In the end, the pressure and the pressure derivative log-log type curves have been drawn up.From the physical percolation mechanism, this paper has also analyzed the influence of the dimensionless quadratic pressure gradient coefficient to the curve shape characteristics of triple porosity reservoir. The impact of the quadratic gradient under certain conditions is extremely intense, and the pressure error is up to 20% and pressure derivative error is up to 30%. Especially for low permeability reservoirs and heavy oil reservoirs, its quadratic gradient coefficient is bigger than the conventional reservoirs; therefore its type curves deviation is much obvious. So if the flow equation ignored the quadratic term will cause a great error of the well test analysis results, the obtained parameter value will not be the real formation parameter value, which will greatly affect the sequel development and dynamic analysis. Therefore, the quadratic pressure gradient term should not be neglected, and the thorough research to the quadratic gradient percolation theory and application should be conducted. The result available can be used in the study of the flow rule and the well test analysis of triple porosity Reservoir.