title: Numerical simulation of the drying of inkjet-printed droplets.
abstract: In this paper we study the behavior of an inkjet-printed droplet of a solute dissolved in a solvent on a solid horizontal surface by numerical simulation. An extended model for drying of a droplet and the final distribution of the solute on an impermeable substrate is proposed. The model extends the work by Deegan, Fischer and Kuerten by taking into account convection, diffusion and adsorption of the solute in order to describe more accurately the surface coverage on the substrate. A spherically shaped droplet is considered such that the model can be formulated as an axially symmetric problem. The droplet dynamics is driven by the combined action of surface tension and evaporation. The fluid flow in the droplet is modeled by the Navier-Stokes equation and the continuity equation, where the lubrication approximation is applied. The rate of evaporation is determined by the distribution of vapor pressure in the air surrounding the droplet. Numerical results are compared with experimental results for droplets of various sizes.
authors.affiliation: Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB Eindhoven, Netherlands. Electronic address: d.p.siregar@tue.nl.
authors.forename: D P
authors.initials: DP
authors.lastname: Siregar
authors.affiliation: Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB Eindhoven, Netherlands; Faculty EEMCS, University of Twente, P.O. Box 217, NL-7500 AE Enschede, Netherlands. Electronic address: j.g.m.kuerten@tue.nl.
authors.forename: J G M
authors.initials: JGM
authors.lastname: Kuerten
authors.affiliation: Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB Eindhoven, Netherlands. Electronic address: c.w.m.v.d.geld@tue.nl.
authors.forename: C W M
authors.initials: CWM
authors.lastname: van der Geld