摘要
目前,对压裂气井的产能预测大部分是建立在单相、稳定或拟稳定渗流的基础上,产能公式大多是解析式,而对非稳态气、水两相渗流压裂气井的产能研究则较薄弱。为此,提出了使用混合PEBI网格对压裂气井产能进行模拟的方法,具有网格节点分布灵活的特点,可以精确地描述裂缝附近的流动状况,避免了常规笛卡尔网格的网格取向效应,同时又满足有限差分方法对网格正交性的要求。将计算结果与现场某气井压裂后产量相比,其吻合程度很高,完全满足现场应用的要求。利用编制的基于混合PEBI网格的压裂气井产能模拟软件对影响压裂气井产能的主要因素进行了研究,结果表明:地层渗透率、裂缝半长以及裂缝导流能力都将显著影响裂缝井的产量。为了获得较好的压裂效果,应在压裂方案编制时充分考虑上述因素的影响,对裂缝参数进行准确的优化设计。
Productivity forecasts are mostly based on the assumptions of single phase,stability or pseudo-stability flow,and the productivity formulas are analytical,while few researches have been done on the fractured gas wells of unstable two-phase flow.A new method using the hybrid PEBI grid to simulate the productivity of fractured gas wells is presented in this paper.The hybrid PEBI grid shows more flexibility and the grid orientation effects can be eliminated effectively.Meanwhile,it meets the perpendicularity of the grid which is required by the finite difference method and fits for reservoir simulation.Comparisons between calculation results and the actual productivity of fractured gas wells in certain fields show excellent agreements,therefore it can be concluded that this method meets field application satisfactorily.By use of the productivity simulation software programmed on basis of the hybrid PEBI grid,several important parameters which influence the productivity of fractured gas wells were analyzed and some useful conclusions were drawn.The results show that formation permeability,fracture half length and flow conductivity have significant influences on the productivity of fractured gas wells.In order to gain better post-fracture response,it is necessary to consider all the influences and optimize these factors.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2009年第11期80-82,共3页
Natural Gas Industry
基金
国家高技术研究发展计划(863计划)(编号:2006AA09Z338)"特殊结构井开发油藏工程技术"
中国石油科技攻关项目"低
特低渗透油气藏有效开发技术研究"(编号:06-02A-02-01)的部分研究成果
关键词
低渗透油气藏
压裂
气井
生产能力
相态
流体流动
模糊数学
数值模拟
low-permeability hydrocarbon reservoir,fracturing,gas well,productivity,phase state,fuzzy mathematics,numerical simulation
