Lattice Boltzmann method for simulation of wettable particles at a fluid-fluid interface under gravity

Area of Science:

• Computational physics
• Fluid dynamics
• Interfacial science

Background:

• Simulating particle behavior at fluid interfaces is crucial for understanding phenomena like emulsion stability and microfluidics.
• Accurate modeling requires robust methods for handling complex boundary conditions and multiphase flow dynamics.

Purpose of the Study:

• To develop and validate a novel computational technique for simulating wettable particles at fluid-fluid interfaces under gravitational effects.
• To assess the technique's accuracy by comparing simulation results with theoretical predictions for various benchmark scenarios.

Main Methods:

• The study employed a hybrid computational approach combining the improved smoothed profile-lattice Boltzmann method (iSP-LBM) for solid-fluid boundary dynamics.
• Free-energy lattice Boltzmann method (LBM) was utilized to describe immiscible two-phase flows.
• Five benchmark problems in 2D systems were simulated, including stationary and moving particles under varying gravitational conditions.

Main Results:

• Simulations accurately reproduced the behavior of wettable particles at fluid interfaces, both in the absence and presence of gravity.
• The technique successfully modeled capillary floatation and immersion forces acting on particles.
• Results showed excellent agreement between computational simulations and theoretical estimations.

Conclusions:

• The developed computational technique is effective for simulating wettable particles at fluid-fluid interfaces under gravity.
• This method provides a reliable tool for investigating interfacial phenomena in multiphase systems.
• The validated technique can be applied to more complex problems in fluid mechanics and materials science.