2009 年 75 巻 756 号 p. 2327-2334
We propose a new approximation method, which calculates shearing forces of a liquid meniscus bridge between parallel plates with small clearance, and discuss the effect of three geometrical parameters, the volume of the bridge, clearance of the planes, and contact angle, on the shearing forces. The method introduces the nonaxisymmetry of the liquid meniscus-bridge by permitting the change of the contact angle on the triple lines, and thereby the calculated shearing forces increase with the shearing distance in the region of lower shearing distance. Experiments were carried out to measure the spring constants of the meniscus bridge in the shearing direction, and showed that the experimental results agreed with the calculated ones qualitatively. Moreover, the shape of the liquid meniscus bridge under shear is consistent with the assumptions of the approximation method. Shearing forces increased with both the volume of the liquid meniscus bridge and the contact angle or with the decrease of clearance.