Jetting Micron-Scale Droplets onto Chemically Heterogeneous Surfaces

TL;DR

This study explores how micron-scale droplets behave when jetted onto chemically patterned surfaces, revealing that droplet shape depends on size, initial conditions, and surface patterning, with numerical models closely matching experimental results.

Contribution

It provides a detailed experimental and numerical analysis of droplet behavior on chemically heterogeneous surfaces, highlighting the importance of initial conditions and surface patterning.

Findings

Droplet shape depends on size relative to stripe pattern.

Numerical models accurately predict droplet dynamics.

Initial position and velocity significantly influence final droplet shape.

Abstract

We report experiments investigating the behaviour of micron-scale fluid droplets jetted onto surfaces patterned with lyophobic and lyophilic stripes. The final droplet shape depends on the droplet size relative to that of the stripes. In particular when the droplet radius is of the same order as the stripe width, the final shape is determined by the dynamic evolution of the drop and shows a sensitive dependence on the initial droplet position and velocity. Numerical solutions of the dynamical equations of motion of the drop provide a close quantitative match to the experimental results. This proves helpful in interpreting the data and allows for accurate prediction of fluid droplet behaviour for a wide range of surfaces.