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arXiv · 2407.18850

Hybrid particle-phase field model and renormalized surface tension in dilute suspensions of nanoparticles

Alexandra J. Hardy·Abdallah Daddi-Moussa-Ider·Elsen Tjhung
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Abstract

We present a two-phase field model and a hybrid particle-phase field model to simulate dilute colloidal sedimentation and flotation near a liquid-gas interface (or fluid-fluid interface in general). Both models are coupled to the incompressible Stokes equation, which is solved numerically using a combination of sine and regular Fourier transforms to account for the no-slip boundary conditions at the boundaries. The continuum two-phase field model allows us to analytically solve the equilibrium interfacial profile using a perturbative approach, demonstrating excellent agreement with numerical simulations. Notably, we show that strong coupling to particle dynamics can significantly alter the liquid-gas interface, thereby modifying the liquid-gas interfacial tension. In particular, we show that the renormalized surface tension is monotonically decreasing with increasing colloidal particle concentration and decreasing buoyant mass.

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Alexandra J. Hardy, Abdallah Daddi-Moussa-Ider, Elsen Tjhung. 2024-07-26. Hybrid particle-phase field model and renormalized surface tension in dilute suspensions of nanoparticles. https://arxiv.org/abs/2407.18850

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