Numerical simulation of drop retraction after a strain jump

Area of Science:

• Fluid dynamics
• Interfacial phenomena
• Non-Newtonian fluid mechanics

Background:

• Spherical liquid drops suspended in immiscible fluids are common in industrial processes.
• Understanding drop deformation and retraction dynamics is crucial for process optimization.
• Previous studies have explored drop behavior under various external forces.

Purpose of the Study:

• To simulate the retraction dynamics of a sheared spherical liquid drop.
• To compare simulation results with experimental data for validation.
• To investigate the underlying mechanisms of the observed relaxation process.

Main Methods:

• Computational fluid dynamics (CFD) simulations were employed.
• The Volume of Fluid (VOF) method was used to track the interface.
• Simulations modeled an instantaneous initial shear applied to the drop.

Main Results:

• The simulation successfully captured the drop's retraction towards its spherical equilibrium.
• A distinct two-step relaxation process was observed in the simulations.
• The simulated retraction dynamics closely matched recent experimental observations.

Conclusions:

• The two-step relaxation process is a key characteristic of sheared liquid drop retraction.
• CFD simulations provide a reliable tool for studying interfacial fluid dynamics.
• This work validates simulation models against experimental data in fluid mechanics.