一种确定水平气井二项式产能方程的新方法

A new method for binomial deliverability equation of horizontal gas well

以往确定水平气井二项式产能方程所需的测试资料在实际操作过程中难以取得,导致常规产能试井和"一点法"应用受限。从水平气井渗流机理出发,结合气藏物质平衡方程,提出了一种计算水平气井二项式产能方程系数的新方法。该方法利用储层和气体基本参数计算二项式产能方程系数A值,结合气藏生产动态资料,通过对井底流压的拟合求取二项式产能方程系数B值。采用该方法计算了四川盆地黄龙场飞仙关组气藏某水平气井的二项式产能方程系数和绝对无阻流量,与压力恢复试井资料计算结果相比,该方法所计算绝对无阻流量的相对误差仅为-4.4%,表明该方法计算的绝对无阻流量具有较高的精度。实例研究证明,该方法在缺乏产能试井资料的气藏中具有较好的应用前景。

Test data for binomial deliverability equation of horizontal gas well is difficult to be obtained in the practical operation,which results in the applications of conventional deliverability test and single point method to be restricted.According to the seepage mechanism of horizontal gas well,combined with gas reservoir material balance equation,a new method calculating binomial deliverability equation coefficients of horizontal gas well are proposed.In this method,basic reservoir and gas parameters are used to calculate binomial deliverability equation coefficient A.The binomial deliverability equation coefficient Bcan be obtained by matching bottom hole flowing pressure,combined with gas reservoir production dynamic data.According to the method,binomial deliverability equation coefficients and absolute open flow of a horizontal gas well in the Huanglongchang Feixianguan gas reservoir of Sichuan Basin is calculated.Compared with calculation results of actual build-up test data,relative error of absolute open flow calculated with this method is only-4.4%,which indicate that the accuracy of calculated absolute open flow is high.Example researches indicate that the method has good application prospect in the gas reservoirs without deliverability test data.