一种毛管压力曲线平均化的新方法

A New Method of Averaging Capillary Pressure Curve

针对传统毛管压力曲线平均化方法中采用幂函数拟合时在曲线末端上翘严重和初始段拟合程度不高的问题,根据毛管压力曲线量化特征,提出了基于分段拟合平均化的新方法。将毛管压力曲线分为初始段、中间平缓段、末端上翘段3部分,分别进行函数拟合,3个方程联立得到表征整条曲线的函数方程,然后计算毛管压力,进而平均。以国内某油田为例,与常规的平均化方法进行曲线形态、拟合优度、标准差的对比,分段拟合平均化方法具有更高的拟合精度,能得到更贴近储层实际的毛管压力曲线。新方法的处理流程适合编制计算机程序,简化了处理工作量。

When power function is used in the traditional averaging capillary pressure curve method, the fitted curve is seriously warped at the end and the fitting degree is not high in the initial section. According to the quantitative characteristics of capillary pressure curve, a new averaging fitting method based on segmented fitting is proposed. The capillary pressure curve is divided into three parts: the initial section, the middle gentle section, and the end upwarping section. Three segments are fitted respectively to obtain the functional equation representing the whole curve, and then the capillary pressure is calculated and averaged. Taking a domestic oil field as an example, the curve shape, fitting goodness and standard deviation are compared with the conventional averaging method.The result shows that higher fitting accuracy and the capillary pressure curve closer to the actual reservoir can be obtained using the segmented fitting averaging method. The processing flow of the new method is suitable for computer programming and simplifies the processing workload.