Estimation of the Drying Length during Particle Assembly By Convective Deposition

Convective deposition is a widely used tool to create well-ordered particle arrays by drawing a suspension across a substrate utilizing evaporation-driven flow to localize and order particles in a thin film. We re-examine the assumption that the length scale associated with the drying front in convective deposition is constant. Over a wide range of parameters, we measure the drying length scale and note that it is inversely proportional to the deposition speed. Using a model of Darcy flow through the deposited particles, we develop a model that is more robust in describing convective deposition than those previously suggested by Nakayama et al.