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arXiv · 0804.0384

Microscale fluid flow induced by thermoviscous expansion along a traveling wave

Franz M. Weinert·Jonas A. Kraus·Thomas Franosch·Dieter Braun
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Abstract

The thermal expansion of a fluid combined with a temperature-dependent viscosity introduces nonlinearities in the Navier-Stokes equations unrelated to the convective momentum current. The couplings generate the possibility for net fluid flow at the microscale controlled by external heating. This novel thermo-mechanical effect is investigated for a thin fluid chamber by a numerical solution of the Navier-Stokes equations and analytically by a perturbation expansion. A demonstration experiment confirms the basic mechanism and quantitatively validates our theoretical analysis.

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Franz M. Weinert, Jonas A. Kraus, Thomas Franosch, Dieter Braun. 2008-04-02. Microscale fluid flow induced by thermoviscous expansion along a traveling wave. https://doi.org/10.1103/physrevlett.100.164501

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