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arXiv · 1109.2372

Large variation in the boundary-condition slippage for a rarefied gas flowing between two surfaces

J. Laurent·A. Drezet·H. Sellier·J. Chevrier·S. Huant
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Abstract

We study the slippage of a gas along mobile rigid walls in the sphere-plane confined geometry and find that it varies considerably with pressure. The classical no-slip boundary condition valid at ambient pressure changes continuously to an almost perfect slip condition in a primary vacuum. Our study emphasizes the key role played by the mean free-path of the gas molecules on the interaction between a confined fluid and solid surfaces and further demonstrates that the macroscopic hydrodynamics approach can be used with confidence even in a primary vacuum environment where it is intuitively expected to fail.

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J. Laurent, A. Drezet, H. Sellier, J. Chevrier, S. Huant. 2011-09-12. Large variation in the boundary-condition slippage for a rarefied gas flowing between two surfaces. https://doi.org/10.1103/physrevlett.107.164501

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