液晶駆動型マイクロアクチュエータの開発 : 第3報,平行平板間速度分布の可視化(<小特集>非ニュートン性,機能性を示す複雑流体の流動と応用)

概要

論文の詳細を見る
As a fundamental study to develop liquid crystalline microactuators, we visualized the backflows induced between parallel plates for varying parameters, such as the twist angle, the cell gap and the applied voltage. A low-molar-mass nematic liquid crystal, 4-cyano-4'-pentyl biphenyl (5CB), was used, and silica particles, whose diameter was 2.5 microns, were dispersed in 5CB. The measurements confirm qualitatively the predictions obtained in the previous study; that is, at 0deg of the twist angle, the velocity component parallel to the anchoring direction of the lower plate shows an S-shaped profile, which is distorted with increasing the twist angle, and finally reaches a unidirectional profile at 180deg of the twist angle. The component perpendicular to the anchoring and gap directions is 0 at 0deg and grows up to an S-shaped profile at 180deg. Since an increase in the applied voltage and a decrease in the cell gap correspond to an increase in the intensity of electric fields, the magnitude of the backflow becomes large. A quantitative agreement between the measurements and the numerical predictions is not obtained, because the effect of the surface tension actualized at the ends of the plate was ignored in the simulation.
社団法人日本機械学会の論文
2009-05-25