Abstract.

I discuss fluid flow at the interface between solids with anisotropic roughness. I show that the Bruggeman effective medium theory and the critical junction theory give nearly the same results for the fluid flow conductivity. This shows that, in most cases, the surface roughness observed at high magnification is irrelevant for fluid flow problems such as the leakage of static seals, and fluid squeeze-out. The effective medium theory predicts that the fluid flow conductivity vanishes at the relative contact area A/A₀ = 0.5 independent of the anisotropy. However, the effective medium theory does not solve the elastic contact mechanics problem but is based on a purely geometric argument. Thus, for anisotropic roughness the contact area may percolate at different values of A/A₀ depending on the direction. We discuss how this may be taken into account in the effective medium and critical junction theories.

Graphical abstract

中文翻译：

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具有各向异性粗糙度的系统的界面流体流动。

摘要。

我讨论了具有各向异性粗糙度的固体之间的界面处的流体流动。我证明了布鲁格曼有效介质理论和临界连接理论给出的流体流导率几乎相同。这表明，在大多数情况下，以高倍观察到的表面粗糙度与流体流动问题（例如静态密封件的泄漏和流体挤出）无关。有效介质理论预测，与各向异性无关，流体流动传导率在相对接触面积A / A ₀ = 0.5处消失。然而，有效介质理论并不能解决弹性接触力学问题，而是基于纯粹的几何学说。因此，对于各向异性粗糙度，接触面积可能会渗透到不同的A / A ₀取决于方向。我们讨论如何在有效的中型和临界型联结理论中考虑这一点。

图形概要