Dynamic contact angles in CFD simulations

• Autorzy: Schönfeld F. , Hardt S.
• Języki publikacji: EN

Abstrakty

EN

The accurate modelling of contact angle properties plays an important role in the simulation of micro flows. We show that computational fluid dynamics (CFD) results of moving contact line problems, however, show a pronounced mesh dependence which is partly inherent to the modelling approach since the (non-integrable) viscous stress divergence at the three-phase contact line is commonly neglected in standard CFD simulations. Moreover, the numerical description of contact angles suffers from artificial diffusion for the used voiume-of-fluid method. Introduction of a macroscopic slip range hi combination with a localised body force close to the contact line turns out to remedy both problems. Considering capillary filling as an example we show that accurate, mesh independent solutions arc obtained already on coarse meshes.

Słowa kluczowe

EN

computational fluid dynamics CFD; CFD; free-surface flow; dynamic contact angles

PL

CFD; komputerowa mechanika płynów; przepływ; kąt zwilżania

• Wydawca: Wydawnictwo Politechniki Częstochowskiej
• Czasopismo: Turbulence : international journal
• Rocznik: 2004
• Tom: Vol. 10
• Strony: 131--138
• Opis fizyczny: Bibliogr. 19 poz.

Twórcy

autor

Schönfeld F.

• Institut für Mikrotechnik Mainz (IMM), Carl-Zeiss Strasse 18-20, D-55129 Mainz, Germany

autor

Hardt S.

• Darmstadt University of Technology, Petersenstrasse 30,0-64287 Darmstadt, Germany

Bibliografia

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