Effective longitudinal slip over grooves encapsulated by a nearly inviscid lubricant

Ory Schnitzer; Ehud Yariv

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arXiv · 2601.20581

Effective longitudinal slip over grooves encapsulated by a nearly inviscid lubricant

Ory Schnitzer·Ehud Yariv

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Abstract

We calculate the effective slip length for a rectangularly grooved periodic surface encapsulated (i.e., fully wetted) by a lubricant fluid and subjected to exterior shear flow parallel to the grooves. Our focus is the limit of a nearly-inviscid lubricant, where the ratio $\mu$ of the lubricant viscosity to that of the exterior fluid is small. This limit is singular for an encapsulated surface, indicating a dominant lubricant-flow effect - a stark contrast to superhydrophobic surfaces where the role of the lubricant is typically negligible.

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Ory Schnitzer, Ehud Yariv. 2026-01-28. Effective longitudinal slip over grooves encapsulated by a nearly inviscid lubricant. https://arxiv.org/abs/2601.20581

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