Force Analysis of Liquid Droplets on Micro-Grooved Surfaces with Air Flow

Abstract

Abstract:

The dynamics of a liquid droplet driven by an air flow and displaced on the micro-grooved surface was investigated, and a force balance model in terms of dynamic contact angle was obtained. Two terms of θ(α) and r (α) were improved in the calculation of capillary force. The term θ(α) was expressed by a piecewise function while term r (α) was deduced by the equation of elliptical contact line. The drag force was simplified by importing the no-slip boundary condition. Then the model was tested in a wind tunnel experimentally. The test results turned out to be consistent with the experimental results, which proved that the force balance model was rational and effective.

Key words: microgroove, droplet, force balance model, dynamic contact angle

CLC Number:

O 353.4

HUANG Suhe,HU Haibao,CHEN Libin,SONG Dong. Force Analysis of Liquid Droplets on Micro-Grooved Surfaces with Air Flow[J]. Journal of Shanghai Jiaotong University, 2014, 48(02): 260-264.

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