确定凝析气藏相态特征和气井产量预测的方法

根据凝析气藏相态特征，建立了一种确定凝析气藏储层凝析油分布规律和预测凝析气井合理产量的方法。首先根据凝析气渗流特点建立并详细地推导了不稳定渗流方程，运用凝析油气两相拟压力函数，推导出三种典型边界，即无限大外边界，有界封闭边界和有界定压边界的压力分布公式;建立了压力与拟压力间的相互关系和气井生产时储层内凝析油分布规律。利用凝析气藏等温衰竭过程中凝析油含量与随压力变化的数据确定出开采过程中储层内凝析油含量的分布特征。考虑到所绘制的凝析气井流人动态曲线——IPR曲线的可靠性，采用气井稳定测试资料来确定其中的重要参数;按气井IPR曲线及储层凝析油含量分布状况优选得出气井合理产量，通过实例Y井结合文中提出的理论与方法，系统提供了确定凝析气井IPR曲线与合理产量的方法。

A METHOD FOR DEFINING CONDENSATE GAS RESERVOIR'S PHASE STATE CHARACTERI STIC AND PREDICTING GAS WELL OPTIMUM OUTPUT

This paper,based on condensate gas reservoir characteristics,presents a method for determining the law of condensate distribution and predicting condensate gas well's optimum output. The first,the combina- tion with condensate gas filtration characteristics has built and inferred in detail the unsteady filtering equation in porous medium. By using the two-phase pseudo-pressure function of condensate oil-gas,the pressure distribution equations have been fetched for three kinds of typical boundaries in condensate gas reservoir,that is,an infinite outer boundary,a finite closed boundary and finite boundary with the constant pressure. And has built the relations between pressure and pseudo-pressure,and the law distributed condensate oil content, when gas well is producing from the reservoir. Using the data of the condensate content change with pressure in constant-temperature,the distributive characterization is defined under producing. Under drawing Inflow Performance Relationship Curve(IPRC)of condensate gas well is considered the curve's reliability. Some important behavior factors are obtained by using the steady-test data of gas well. To combine IPRC of gas well with the distribution condition of condensate content in formation,the condensate gas well's optimum output is selected. By means of example well A, combination this paper presented theory with the method, the method has systematically provided for defining condensate gas well's IPRC and optimum output.