Finite element formulation of fluctuating hydrodynamics for fluids filled with rigid particles using boundary fitted meshes

De Corato, M. ; Slot, J.J.M. ; Hütter, M. ; D'Avino, G. ; Maffettone, P.L. ; Hulsen, M.A.

Resumen: In this paper, we present a finite element implementation of fluctuating hydrodynamics with a moving boundary fitted mesh for treating the suspended particles. The thermal fluctuations are incorporated into the continuum equations using the Landau and Lifshitz approach [1]. The proposed implementation fulfills the fluctuation–dissipation theorem exactly at the discrete level. Since we restrict the equations to the creeping flow case, this takes the form of a relation between the diffusion coefficient matrix and friction matrix both at the particle and nodal level of the finite elements. Brownian motion of arbitrarily shaped particles in complex confinements can be considered within the present formulation. A multi-step time integration scheme is developed to correctly capture the drift term required in the stochastic differential equation (SDE) describing the evolution of the positions of the particles. The proposed approach is validated by simulating the Brownian motion of a sphere between two parallel plates and the motion of a spherical particle in a cylindrical cavity. The time integration algorithm and the fluctuating hydrodynamics implementation are then applied to study the diffusion and the equilibrium probability distribution of a confined circle under an external harmonic potential.

Idioma: Inglés

DOI: 10.1016/j.jcp.2016.04.040

Año: 2016

Publicado en: Journal of Computational Physics 316 (2016), 632-651
ISSN: 0021-9991

Factor impacto JCR: 2.744 (2016)

Categ. JCR: PHYSICS, MATHEMATICAL rank: 3 / 55 = 0.055 (2016) - Q1 - T1
Categ. JCR: COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS rank: 26 / 105 = 0.248 (2016) - Q1 - T1

Factor impacto SCIMAGO: 2.048 - Physics and Astronomy (miscellaneous) (Q1) - Computer Science Applications (Q1)

Tipo y forma: Article (PostPrint)