Capillary attraction of floating rods

• Published in: Engineering analysis with boundary elements Vol. 36; no. 5; pp. 836 - 844
• Main Author: Pozrikidis, C.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2012; Elsevier
• Subjects: Boundary-element method; Capillary attraction; Computational methods in fluid dynamics; Exact sciences and technology; Floating particles; Fluid dynamics; Fundamental areas of phenomenology (including applications); Physics; Stokes flow; Capillary attraction; Boundary-element method; Floating particles; Stokes flow; Vertical; Fluid fluid interfaces; Attraction; Translation; Particle motion; Digital simulation; Buoyancy; Transient flow; Rotation speed; Boundary integral method; Natural convection; Weight; Separation method; Hydrostatics; Capillarity; Circular cylinder; Modelling; Surface tension; Floating body; Boundary element method
• ISSN: 0955-7997; 1873-197X
• DOI: 10.1016/j.enganabound.2011.11.012

The capillary attraction of two parallel cylinders with circular cross-section representing slender particles floating at the interface between two immiscible fluids is considered. Given the particle separation, the elevation of the particle centers in hydrostatics is computed to satisfy the vertical force balance involving the buoyancy force, the capillary force, and the particle weight. A numerical procedure is developed for calculating the horizontal force exerted on a pair of cylinders in solitary or periodic arrangement. The results confirm that the particles attract each other under the conditions considered. The particle motion and transient flow due to the particle attraction are computed using a boundary-integral method for Stokes flow. In the algorithm, the particle center velocity of translation and angular velocity of rotation are calculated to satisfy force and torque balances. Numerical simulations using a boundary-element method subject to an initial state provided by hydrostatics illustrate the nature of the motion and furnish estimates for the particle velocity induced by capillarity.