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arXiv · 1103.0142

Momentum and Mass Fluxes in a Gas Confined between Periodically Structured Surfaces at Different Temperatures

A. A. Donkov·Sudarshan Tiwari·Tengfei Liang·Steffen Hardt·Axel Klar·Wenjing Ye
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Abstract

It is well known that in a gas-filled duct or channel along which a temperature gradient is applied, a thermal creep flow is created. Here we show that a mass and momentum flux can also be induced in a gas confined between two parallel structured surfaces at different temperatures, i.e. \textit{orthogonal} to the temperature gradient. We use both analytical and numerical methods to compute the resulting fluxes. The momentum flux assumes its maximum value in the free-molecular flow regime, the (normalized) mass flux in the transition flow regime. The discovered phenomena could find applications in novel methods for energy-conversion and thermal pumping of gases.

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A. A. Donkov, Sudarshan Tiwari, Tengfei Liang, Steffen Hardt, Axel Klar, Wenjing Ye. 2011-07-19. Momentum and Mass Fluxes in a Gas Confined between Periodically Structured Surfaces at Different Temperatures. https://doi.org/10.1103/physreve.84.016304

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