Pinning-depinning mechanism of the contact line during evaporation on chemically patterned surfaces: A lattice Boltzmann study

Abstract

In this paper, the pinning and depinning mechanism of the contact line during droplet evaporation on chemically stripe-patterned surfaces is numerically investigated using a thermal multiphase lattice Boltzmann (LB) model with liquid-vapor phase change. A local force balance in the context of diffuse interfaces is introduced to explain the equilibrium states of droplets on chemically patterned surfaces. It is shown that, when the contact line is pinned on a hydrophobic-hydrophilic boundary, different contact angles can be interpreted as the variation of the length of the contact line occupied by each component. The stick-slip-jump behavior of evaporating droplets on chemically patterned surfaces is well captured by the LB simulations. Particularly, a slow movement of the contact line is clearly observed during the stick (pinning) mode, which shows that the pinning of the contact line during droplet evaporation on chemically stripe-patterned surfaces is actually a dynamic pinning process and the dynamic equilibrium is achieved by the self-adjustment of the contact lines occupied by each component. Moreover, it is shown that, when the surface tension varies with the temperature, the Marangoni effect has an important influence on the depinning of the contact line, which occurs when the horizontal component (towards the center of the droplet) of the force caused by the Marangoni stress overcomes the unbalanced Young's force towards outside.

Accepted by Langmuir, 10 figures

References in corpus (6)

• Lattice Boltzmann methods for multiphase flow and phase-change heat transfer
• Lattice Boltzmann modeling of boiling heat transfer: The boiling curve and the effects of wettability
• Modelling contact angle hysteresis on chemically patterned and superhydrophobic surfaces
• Improved axisymmetric lattice Boltzmann scheme
• Lattice Boltzmann modeling of self-propelled Leidenfrost droplets on ratchet surfaces
• Controlling drop size and polydispersity using chemically patterned surfaces

Cited by in corpus (14)

• Implementation of contact angles in the pseudopotential lattice Boltzmann simulations with curved boundaries
• Three-dimensional non-orthogonal multiple-relaxation-time lattice Boltzmann model for multiphase flows
• Enhancement of nucleate boiling by combining the effects of surface structure and mixed wettability: A lattice Boltzmann study
• Evaporation of dilute sodium dodecyl sulfate droplets on a hydrophobic substrate
• Surface declination governed asymmetric sessile droplet evaporation
• Diffusion dominated evaporation in multicomponent lattice Boltzmann simulations
• Water under the Ridge: Evaporation, Translation, Crumpling and Encapsulation of a Water Droplet atop a Liquid Polymeric Film
• Hybrid phase-change lattice Boltzmann simulation of the bubble nucleation and different boiling regimes of conjugate boiling heat transfer
• Lattice Boltzmann simulations of the pool boiling curves above horizontal heaters with homogenous and heterogeneous wettability
• Contact Angle Measurement in Lattice Boltzmann Method
• Lateral Drop Rebound on Hydrophobic and Chemically Heterogeneous Surface
• Light-Guided Surface Plasmonic Bubble Movement via Contact Line De-Pinning by In-Situ Deposited Plasmonic Nanoparticle Heating
• Statics and Dynamics of Polymeric Droplets on Chemically Homogeneous and Heterogeneous Substrates
• Pseudopotential multiple-relaxation-time lattice Boltzmann simulation of vapor condensation on vertical subcooled walls