title: Impact of particle-laden drops: Particle distribution on the substrate.
abstract: The splat morphology after the impact of suspension drops on hydrophilic (glass) and hydrophobic (polycarbonate) substrates was investigated. The suspensions were mixtures of water and spherical hydrophobic particles with diameter of 200μm or 500μm. The impact was studied by side, bottom and angled view images. At Reynolds and Weber numbers in the range 150⩽We⩽750 and 7100⩽Re⩽16,400, the particles distributed in a monolayer on the hydrophilic substrates. It was found that the 200μm particles self-arranged as rings or disks on the hydrophilic substrates. On hydrophobic substrates, many particles were at the air-water interface and 200μm formed a crown-like structure. The current study for impact of particle-laden drops shows that the morphology of splats depends on the substrate wettability, the particle size and impact velocity. We developed correlations for the inner and outer diameter of the particle distribution on the hydrophilic substrates, and for the crown height on hydrophobic substrates. The proposed correlations capture the character of the particle distributions after drop impact that depends on particle volume fraction, the wettability of both particles and the substrate, and the dimensionless numbers such as Reynolds and Weber.
authors.affiliation: Center for Design, Manufacturing and Materials, Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Building 3, Moscow 143026, Russia; Service de Chimie-Physique EP, CP165-62, Université Libre de Bruxelles, 50 Av. F.D. Roosevelt 1050, Brussels, Belgium. Electronic address: v.grishaev@skoltech.ru.
authors.forename: Viktor
authors.initials: V
authors.lastname: Grishaev
authors.affiliation: Service de Chimie-Physique EP, CP165-62, Université Libre de Bruxelles, 50 Av. F.D. Roosevelt 1050, Brussels, Belgium. Electronic address: ciorio@ulb.ac.be.
authors.forename: Carlo Saverio
authors.initials: CS
authors.lastname: Iorio
authors.affiliation: Service de Chimie-Physique EP, CP165-62, Université Libre de Bruxelles, 50 Av. F.D. Roosevelt 1050, Brussels, Belgium. Electronic address: frdubois@ulb.ac.be.
authors.forename: Frank
authors.initials: F
authors.lastname: Dubois
authors.affiliation: Department of Mechanical Engineering, York University, Toronto, ON M3J 1P3, Canada. Electronic address: alidad2@yorku.ca.
authors.forename: A
authors.initials: A
authors.lastname: Amirfazli
keywords: Drop impact; Particle distribution; Splat; Suspension; Volume fraction; Wettability