Sub-core properties of reservoir rocks are known to have a substantial impact on core-scale flow and saturation distribution, particularly considering CO₂-brine coreflooding. Estimating these properties is important for various applications, e.g., investigation of capillary trapping and numerical modeling of coreflooding experiments. In this work we present an improved method for the procedure of Krause et al. (2013) to estimate sub-core characteristic relative permeability and three-dimensional permeability distribution and apply the method to a CO₂-water drainage coreflood experiment. The main novelty of the new method is its efficiency, incorporating a simplified procedure for characteristic curve estimation requiring only single-phase flow solutions. The second novelty is the use of saturation data from multiple coreflooding experiments with varying fractional flow of injection. The proposed procedure, using single-phase solutions instead of two-phase flow simulations, is also expected to reduce numerical errors. The results of applying the method to an experiment are presented and shown to validate the simplified method for characteristic curve estimation. Simulations using the estimated properties as input are shown to produce output that approximately match experimental results, considering a number of fractional flows. The new method is found to be about 50–100 times faster to compute in comparison to previous methods with more dramatic speedup for highly heterogeneous rocks.

众所周知，储层岩石的亚岩心性质对岩心尺度的流动和饱和度分布有重大影响，特别是考虑到CO ₂卤水岩心驱替。评估这些特性对于各种应用非常重要，例如，研究毛细管捕集和岩心驱替实验的数值模型。在这项工作中，我们为Krause等人的程序提出了一种改进的方法。（2013）估算子岩心特征相对渗透率和三维渗透率分布，并将该方法应用于CO ₂排水岩心驱油实验。新方法的主要新颖之处在于它的效率，它结合了简化的特性曲线估算程序，仅需单相流解即可。第二个新颖之处是使用来自多个岩心驱替实验的饱和度数据以及不同的注入分数流量。使用单相解决方案代替两相流模拟的拟议程序也有望减少数值误差。提出并显示了将该方法应用于实验的结果，以验证简化的特征曲线估计方法。考虑到许多分流，使用估计特性作为输入的模拟显示出产生的输出与实验结果大致匹配。