Drying mechanism of monodisperse colloidal film: Evolution of normal stress and its correlation with microstructure

We investigate the drying process of monodisperse colloidal film over a wide range of Péclet number (Pe) by using the Brownian dynamics simulation. We analyze the detailed process in three aspects; accumulation front, normal stress, and microstructure. The evolution of particle distribution is quantified by tracking the accumulation front. The accumulated particles contribute to the continuous increase of the normal stress at the interface. At the substrate, the normal stress first stays constant and then increases as the accumulation front touches the substrate. We quantitatively analyze the stress development by a scaled normal stress difference between the two boundaries. At all tested Pe, the stress difference increases to the maximum, followed by a decrease during drying. Interestingly, a mismatch is observed between the stress difference maximum and the initial stress increase at the substrate. The microstructural analysis reveals that this mismatch is related to the microstructural development at the substrate.

Temporal evolution of concentration and microstructure of colloidal films during vertical drying: a lattice Boltzmann simulation study

Computer simulations of colloidal film drying including hydrodynamic interactions between the particles.

Microstructures and mechanics in the colloidal film drying process

Brownian dynamics simulations and continuum models reveal the rich structural and mechanical features of the colloidal film drying processes with constant velocity and constant normal stress interface movements.