Liquid Bridges in Non-Axisymmetrically Buckled Elastic Tubes: Results for Zero Surface Tension

If the surface tension is negligible then there is no pressure jump over the meniscus: the wall is compressed by the spatially constant external pressure. When this external pressure exceeds a critical value, the tube buckles non-axisymmetrically but its cross-section is the same throughout its length. The axial position of the liquid bridge in a uniformly collapsed tube is arbitrary. For the example shown below, it was fixed by keeping the apex of the meniscus attached to `end' of the tube at z=0.

The figure above shows a sequence of increasingly strongly collapsed tubes, containing a single meniscus. The meniscus shape is completely determined by the wall shape and the contact angle (10o for the example shown). Note how a long thin `meniscus finger' develops along the tube's centreline as the tube's collapse increases. The development of this meniscus finger is closely related to the fact that the meniscus is a surface of constant mean curvature.

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Page last modified: February, 23 1998

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