摘要
针对目前低渗透气藏气水同产井产能评价时遇到的问题,依据渗流力学中气水两相不稳定渗流的基本方程,采用气藏工程方法和改进的修正等时试井方法及热力学原理,并考虑井下油嘴节流及气体高速非达西和滑脱效应的影响,提出了低渗透高含水气藏的产能评价方法。该方法在理论推导的基础上,对气水两相广义拟压力和修正等时试井方法进行了改进,最后结合井下油嘴节流原理和气体通过油嘴时的滑脱效应方程,利用热力学方法和数值分析方法,求出气水同产井的产气能力及最大携液流量。根据模拟井数据,分别用传统产能评价方法和上述方法进行了计算,计算结果表明:传统方法的计算值偏高,而上方法的计算结果比较符合实际。这为低渗透高含水气藏下入井下节流器的气井的产能评价提供了新的思路。
Aiming at the problems encountered in the productivity evaluation of a gas-water well in low permeability gas reservoirs,based on the basic equations of gas-water two phase unsteady state flow equation together with the method of gas reservoir engineering and the improved modified isochronal testing and thermodynamic principle,a method of productivity evaluation for low permeability and high water saturation gas reservoir is proposed with the consideration of downhole choke and high velocity non-Darcy flow and the influence of slippage effect.Based on the theoretical derivation,the proposed method has improved the gas water pseudo pressure and the method of modified isochronal testing.Combined with the principle of downhole choke and the equations of slippage effect when gases passing the choke,gas deliverability and the maximum water-carrying capacity are determined for a gas-water well through thermodynamics and numerical analysis.According to the data on the simulated wells,calculations with traditional methods and this new method are respectively carried out and the results show that the values calculated by use of traditional methods are a bit larger while the value by use of this new method is practical.This study provides new solutions to the productivity evaluation for a gas well with a downhole choke in low permeability and high water saturation gas reservoirs.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2011年第2期66-69,127,共4页
Natural Gas Industry
基金
国家重点基础研究发展规划(973计划)项目(编号:2007CB209506)
关键词
低渗透气藏
高含水气藏
气水同产井
生产能力
井下节流
滑脱效应
评价
low permeability reservoir,high water saturation gas reservoir,gas water well,production capacity,downhole choke,slippage effect,evaluation
