On the concept of macroscopic capillary pressure in two-phase porous media flow
On the concept of macroscopic capillary pressure in two-phase porous media flow
复制标题
DOI：
10.1016/j.advwatres.2019.103487
复制
发表时间：
2020
影响因子：
4.7
通讯作者：
M. Starnoni;D. Pokrajac
中科院分区：
文献类型：
--
作者：
M. Starnoni;D. Pokrajac
尽管两相流体在多孔介质中的流动已经是一个成熟的研究领域，但其理论基础仍然不完善。特别是，虽然毛细压力的普遍定义存在于微观尺度，其放大到宏观尺度仍然相当模糊。在这项工作中，提出了一个清晰而严格的定义，宏观毛细管压力，这自然从应用程序的体积平均的方法，在多相系统的界面特性。宏观毛细压力和介质平均性质之间的关系由流体-流体界面的宏观动量平衡给出，其形式可以解释为宏观尺度下的广义Young-Laplace方程。然后，我们提出的模拟结果中提取的三维微观CT图像的一个真实的碳酸盐岩的多孔区域的排水，并显示我们的配方是如何不同于标准的，这是常用的现场规模的计算代码。
Although two-phase fluid flow in porous media has been an established research field for decades, its theoretical background is still incomplete. In particular, while a universal definition of capillary pressure exists at the micro-scale, its upscaling to the macro-scale is still rather vague. In this work, a clear and rigorous definition of the macroscopic capillary pressure is proposed, which follows naturally from application of the method of volume averaging to interface properties in multiphase systems. The relationship between the macroscopic capillary pressure and the average properties of the medium is given by the macroscopic momentum balance for the fluid-fluid interfaces, in a form which can be interpreted as a generalized Young-Laplace equation at the macro-scale. We then present simulation results of drainage in a porous region extracted from a three-dimensional micro-CT image of a real carbonate rock, and show how our formulation differs from the standard one which is commonly employed in field-scale computational codes.