To date many methods of constructing porous media have been proposed. Among them, the multiple-point statistics (MPS) method has a unique advantage in reconstructing 3D pore space because it can reproduce pore space of long-range connectivity. The Single Normal Equation Simulation (SNESIM) is one of most commonly used algorithms of MPS. In the SNESIM algorithm, the selection of training image is vital because it contains the basic pore structure patterns. In the previous reconstructions of 3D porous media using SNESIM, a 2D slice was usually employed as the training image. However, it is difficult for a 2D slice to contain complex 3D pore space geometry and topology patterns. In this paper, a 3D training image is used in order to provide more realistic 3D pore structure features. Besides, a multi-grid search template is applied for the purpose of capturing the pore structures of different scales and speeding up the reconstruction process. Two sandstone cores are taken as test examples and the 3D porous media are reconstructed. The two-point correlation function, pore network structure parameters and absolute permeability are applied as the evaluation indexes to validate the accuracy of the reconstructed models. The comparison result shows that the reconstructed models are in good agreement with the real model obtained by X-ray computed tomography scanning in the pore throat geometry and topology and transport property, which justifies the reliability of the proposed method.

迄今为止，已经提出了许多构造多孔介质的方法。其中，多点统计（MPS）方法在重建3D孔隙空间方面具有独特优势，因为它可以重现远程连接的孔隙空间。单一正则方程模拟（SNESIM）是MPS最常用的算法之一。在SNESIM算法中，训练图像的选择至关重要，因为它包含基本的孔结构图案。在以前使用SNESIM重建3D多孔介质的过程中，通常将2D切片用作训练图像。但是，2D切片很难包含复杂的3D孔隙空间几何形状和拓扑图。在本文中，使用3D训练图像以提供更逼真的3D孔结构特征。除了，为了捕获不同尺度的孔结构并加快重建过程，应用了多网格搜索模板。以两个砂岩岩心为例，重建了3D多孔介质。将两点相关函数，孔隙网络结构参数和绝对渗透率用作评估指标，以验证所构建模型的准确性。比较结果表明，所重建的模型与X射线计算机断层扫描扫描得到的真实模型在孔喉的几何形状，拓扑结构和传输特性方面吻合良好，证明了所提方法的可靠性。以两个砂岩岩心为例，重建了3D多孔介质。以两点相关函数，孔隙网络结构参数和绝对渗透率作为评价指标，验证了所建模型的准确性。比较结果表明，所重建的模型与X射线计算机断层扫描扫描得到的真实模型在孔喉的几何形状，拓扑结构和传输特性方面吻合良好，证明了所提方法的可靠性。以两个砂岩岩心为例，重建了3D多孔介质。将两点相关函数，孔隙网络结构参数和绝对渗透率用作评估指标，以验证所构建模型的准确性。比较结果表明，所重建的模型与X射线计算机断层扫描扫描得到的真实模型在孔喉的几何形状，拓扑结构和传输特性方面吻合良好，证明了所提方法的可靠性。