A method of determining waterflood residual oil saturation includes testing, in a laboratory multispeed centrifuge test, a reservoir core sample to obtain a set of average water saturation (Sw,avg) and imbibition capillary pressure (Pci) data points, applying in a best-fit smoothing function to the data points to obtain a best-fit average saturation curve, converting the best-fit average saturation curve to an outlet-face saturation curve, applying a best-fit straight line to the outlet-face saturation curve associated with a substantially constant outlet water saturation and changing imbibition capillary pressure, and determining a waterflood residual oil saturation (Sorw) of the core sample. The waterflood residual oil saturation is associated with a point on the outlet-face saturation curve where the best-fit straight line deviates from the outlet-face saturation curve.
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机译：确定注水残余油饱和度的方法包括在实验室多速离心机测试中测试储层岩心样本，以获得一组平均水饱和度（S ）和吸水毛细管压力（P < Sub> ci ）数据点，对数据点应用最适合的平滑函数，以获得最适合的平均饱和度曲线，将最适合的平均饱和度曲线转换为出口面饱和度曲线，然后应用与出口表面饱和度曲线的最佳拟合直线，该曲线与出口水饱和度基本恒定和吸收毛细管压力的变化有关，并确定岩心样品的注水残余油饱和度（S orw ）。注水残余油饱和度与出口面饱和度曲线上的一个点相关，其中最佳拟合直线偏离出口面饱和度曲线。
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