A sessile liquid drop can deform the substrate on which it rests if the solid is sufficiently “soft.” In this paper we compute the detailed spatial structure of the capillary forces exerted by the drop on the solid substrate using a model based on Density Functional Theory. We show that, in addition to the normal forces, the drop exerts a previously unaccounted tangential force. The resultant effect on the solid is a pulling force near the contact line directed towards the interior of the drop, i.e., not along the interface. The resulting elastic deformations of the solid are worked out and illustrate the importance of the tangential forces.
Skip Nav Destination
Research Article| July 27 2011
Elastic deformation due to tangential capillary forces
Siddhartha Das, Antonin Marchand, Bruno Andreotti, Jacco H. Snoeijer; Elastic deformation due to tangential capillary forces. Physics of Fluids 1 July 2011; 23 (7): 072006. https://doi.org/10.1063/1.3615640
Download citation file: