Numerical simulations of the pressure-driven flow of pairs of rigid spheres in elastoviscoplastic fluids

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Esposito, Giancarlo, Tsamopoulos, John, Villone, Massimiliano Maria, D'Avino, Gaetano
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866918018087387136
author Esposito, Giancarlo
Tsamopoulos, John
Villone, Massimiliano Maria
D'Avino, Gaetano
author_facet Esposito, Giancarlo
Tsamopoulos, John
Villone, Massimiliano Maria
D'Avino, Gaetano
contents We investigate through numerical simulations the hydrodynamic interactions between two rigid spherical particles suspended on the axis of a cylindrical tube filled with an elastoviscoplastic fluid subjected to pressure-driven flow. The simulations are performed by the finite element method with the arbitrary Lagrangian-Eulerian formulation. We carry out a parametric analysis to examine the impact of the yield stress and relaxation time of the fluid and of particle confinement on the dynamics of the system. We identify master curves of the particle relative velocity as a function of the inter-particle distance. When the yield stress of the suspending phase is much lower than the viscous stress, those curves highlight short-range attractive interactions and long-range repulsive interactions between particles, with the latter specifically promoting their alignment. As the yield stress increases, the attractive interaction is replaced by stasis at short distance, characterized by a vanishing relative velocity and the formation of an unyielded region that connects the two spheres, where the fluid behaves like a viscoelastic solid. Additionally, the combined effects of plasticity and elasticity enhance the repulsion between the particles, promoting their ordering. Also increasing the confinement of the particles enhances repulsion, thus allowing to achieve ordering within shorter lengths in the flow direction. Reducing shear thinning amplifies peak relative velocities and expands the attractive region due to increased viscoelastic stresses and stress gradients. While a stable equilibrium may appear at larger separations, its impact is limited by low relative velocities.
format Preprint
id arxiv_https___arxiv_org_abs_2504_02419
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Numerical simulations of the pressure-driven flow of pairs of rigid spheres in elastoviscoplastic fluids
Esposito, Giancarlo
Tsamopoulos, John
Villone, Massimiliano Maria
D'Avino, Gaetano
Fluid Dynamics
We investigate through numerical simulations the hydrodynamic interactions between two rigid spherical particles suspended on the axis of a cylindrical tube filled with an elastoviscoplastic fluid subjected to pressure-driven flow. The simulations are performed by the finite element method with the arbitrary Lagrangian-Eulerian formulation. We carry out a parametric analysis to examine the impact of the yield stress and relaxation time of the fluid and of particle confinement on the dynamics of the system. We identify master curves of the particle relative velocity as a function of the inter-particle distance. When the yield stress of the suspending phase is much lower than the viscous stress, those curves highlight short-range attractive interactions and long-range repulsive interactions between particles, with the latter specifically promoting their alignment. As the yield stress increases, the attractive interaction is replaced by stasis at short distance, characterized by a vanishing relative velocity and the formation of an unyielded region that connects the two spheres, where the fluid behaves like a viscoelastic solid. Additionally, the combined effects of plasticity and elasticity enhance the repulsion between the particles, promoting their ordering. Also increasing the confinement of the particles enhances repulsion, thus allowing to achieve ordering within shorter lengths in the flow direction. Reducing shear thinning amplifies peak relative velocities and expands the attractive region due to increased viscoelastic stresses and stress gradients. While a stable equilibrium may appear at larger separations, its impact is limited by low relative velocities.
title Numerical simulations of the pressure-driven flow of pairs of rigid spheres in elastoviscoplastic fluids
topic Fluid Dynamics
url https://arxiv.org/abs/2504.02419