低速非达西渗流试井模型的一种新的求解方法

流体流动边界不断向外扩展是低速非达西渗流压力降落试井模型的特点。针对这种情况，建立了基于低速非达西渗流规律的固定边界试井模型，并用幂级数求解法求得模型的解析解，在计算压力降落试井标准曲线时，根据流体从静止到流动所需的启动压差确定不同时刻对应的流动区域半径，再用固定边界模型解析解计算井底压力与时间的对应关系，以此作为动边界模型试井曲线的一种数值逼近。应用这种特殊求解方法进行分析计算，发现了低速非达西渗流试井模型的一些重要动态特征。

A New Solution for the Well Testing Model of Low Velocity Nondarcy Percolation

Fluid flowing barrier extends outwards continuously is a feature of pressure draw-down test model with low velocity nondarcy percolation. In view of this situation,a fixed boundary test model based on the pattern of low velocity nondarcy percolation is created, and analytical solution of the model is worked out with power series solution, when the type curve of pressure draw - down test is calculated, the radiuses of flowing area corresponding to the different time intervals in accordance with the starting differential pressure needed by fluid from static to flowing condition, analytical solution of fixed boundary model is then used to calculate the correlation of bottom hole pressure vs time,which is regarded as a numerical approximation to well testing curve of dynamic boundary model. The analysis and calculation using such specific solution discovers some important dynamic behaviour for well testing model of low velocity nondarcy percolation.