确定气井高速湍流系数方法的应用与对比

Application and comparison of method for determining high velocity turbulence flow
coefficient of gas well

陈元千 郭二鹏 张枫

中国石油勘探开发研究院，北京 100083 燕山大学车辆与能源学院，河北 秦皇岛 066004

高速湍流系数又称为高速惯性阻力系数，是判断气井流动状态的一个重要参数。在气井生产的条件下，流向气井井底的气体，因渗流面积的不断减小，气体流动速度不断增加，致使在近井地带形成了非达西流动的湍流影响，引起了附加的压力损失，产生了湍流表皮因子，降低了气井的产能。气井高速湍流的影响程度，还可以利用非达西流动常数和湍流表皮因子描述。在气井二项式的基础上，提出了确定气井高速湍流系数的多点法和一点法，即利用气井的多点或单井测试资料，确定气井的高速湍流系数，并用于非达西流动常数和湍流表皮因子的确定。通过实例的应用表明，提供的方法是实用有效的。同时，还列出了在文献中常用的一些相关经验公式。

High velocity turbulence flow coefficient is also called high velocity inertial resistance coefficient. It is an important parameter for judging flowing conditions of gas well. Under the producing condition of gas well, due to the decrease of filtering flow area, the flow velocity of gas is increasing, the turbulent flow influence of non-Darcy flow is formed,resulting in additional pressure drawdown at the near wellbore zone. Therefore, the turbulent flow skin factor is formed and the production rate of gas well declines. The effect of high velocity turbulence flow can also be described by non-Darcy flow constant and turbulent flow skin factor. Based
on the quadratic form of gas well, one point method and multipoint method are proposed in this paper, which utilizes the multipoint and one point testing data to determine the high velocity turbulence flow coefficient. The non-Darcy flow constant and turbulent flow skin factor can also be determined. The application of the example indicates that the methods are practical and effective. At the same time, some correlation formulae commonly used in the references are listed in the paper.