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Microscale fluid flow induced by thermoviscous expansion along a traveling wave

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 نشر من قبل Jonas Kraus A.
 تاريخ النشر 2008
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Franz M. Weinert




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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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