A new three dimensional cumulant phase field lattice Boltzmann method to study soluble surfactant

Surfactants play a critical role in the physics of paint and coating formulations, affecting key rheological properties such as viscosity, yield stress, thixotropy. This paper proposes new three-dimensional phase-field model that uses cumulant lattice Boltzmann method (LBM) to simulate soluble surfactants. Although current models commonly use Langmuir's relationship, they cannot calculate interfacial tension analytically, or LBM used are unstable when viscosities low. However, proposed overcomes these limitations through two main features. First, parameters for modeling controlling surfactant's strength interaction with other phases directly obtained from given initial bulk surfactant, eliminating need trial-and-error simulations. Second, equilibrium distribution function moment space includes diagonal off elements pressure tensor is minimize Galilean invariance violation. Additionally, there no an external force recover multiphase flows, which could break mass conservation. Furthermore, this has significant potential parallelization since only one neighbor's cell discretization. The shows Langmuir relation behavior validated analytical solutions various tensions surfactant concentrations. Moreover, demonstrates influence surfactants on spurious velocities, indicating method's stability at low viscosities. dynamics droplets presence studied spinodal decomposition under forces. accurately simulates breaking-up coalescence cases. successfully breakage liquid thread high viscosity ratio.