气井拟压力弹性一相法的推导、简化及应用  

Derivation,simplification and application of the pseudo-pressure elastic one-phase method for gas wells

作　　者：陈元千[1] CHEN Yuanqian(Research Institute of Petroleum Exploration&Development,PetroChina,Beijing City,100083,China)

机构地区：[1]中国石油勘探开发研究院,北京100083

出　　处：《油气地质与采收率》2024年第6期89-95,共7页Petroleum Geology and Recovery Efficiency

摘　　要：对于一口处在封闭边界之内的新气井,以某稳定产量开井生产,进行了压降曲线测试。从理论上讲,又可将压降曲线按其压力动态划分为非稳态阶段、过渡阶段(又称为非稳态阶段的后期)和拟稳态阶段。所谓非稳态阶段,是指气井压降漏斗的外缘半径,尚未达到边界之前的范围。而所谓过渡阶段,是指由非稳态阶段过渡到拟稳态阶段的范围。对于拟稳态阶段,我国称为弹性二相法,可用于确定气井控制的原始地质储量。该法被连续四次列于国家油气的行业标准。对于非稳态阶段,本文基于达西定律的平面径向流微分式,利用AI-Hussainy提出的拟压力函数,经推导得到了拟压力的弹性一相法。利用该法可以评价气藏的有效渗透率和井的总表皮系数。同时,利用Wattenbarger对拟压力函数性质的研究结果,通过简化得到了由压力一次方和压力平方表示的弹性一相法。通过实例应用结果表示,三种方法评价的结果是一致的。For the new gas well with a closed boundary,the pressure drawdown curve testing was carried out after it operated at a stable production rate.Theoretically,the pressure drawdown curve can be divided into an unsteady state stage,a transit state stage(also called the late unsteady state stage),and a pseudo-steady state stage according to its pressure dynamics.The unsteady state stage refers to the outer edge radius of the pressure drawdown distribution of the gas well not reaching the boundary.The transit state stage refers to the range from the unsteady state stage to the pseudo-steady state stage.At this stage,the elastic two-phase method used in China can be employed to determine the initial gas in place controlled by a gas well.This method has been listed four times in the national oil and gas industry standard.For the unsteady state stage,according to the differential formula of the plane radial flow based on Darcy’s law,this paper derived the elastic one-phase method of pseudo-pressure by using the pseudo-pressure function proposed by Al-Hussainy.This method could be used to evaluate the effective permeability of gas reservoirs and the total skin factor of wells.In addition,the elastic one-phase method expressed by the one power of pressure and pressure that was squared was obtained by simplifying the research results of Wattenbanger on the properties of the pseudo-pressure function.The practical application showed that the evaluation results with the three methods were consistent.

关 键 词：气井 弹性一相法 拟压力 压力一次方 压力平方 有效渗透率 总表皮系数 

分 类 号：TE328[石油与天然气工程—油气田开发工程]