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Abstract
As a follow up to an earlier work (Phys. Fluids 34, 014108, 2022), where the main focus was on the modes of convection in a threedimensional cubic enclosure filled with a Pr=7 liquid undergoing vibrations in a direction 'parallel' to the imposed temperature gradient, the present study considers the modes of particle clustering, which occur when solid spheres, with density ratio ξ=1.85 or 0.3 and Stokes number (St) between 0.5 and 3.5 x 10^{5}, are added to the fluid. Starting from a uniform distribution of solid particles and fluid in quiescent conditions, the governing equations for the involved phases are numerically solved in their complete, timedependent and nonlinear form for a representative vibrational Rayleigh number (8.34×10^{4}), angular frequency Ω=50 and nondimensional acceleration amplitude (γ) spanning the interval 0.4x10^{7}≤
γ≤3.4x10^{7}. It is shown that, while for relatively high values of St and/or γ, only degenerate states are obtained, where all particles collapse on planar structures, for intermediate values of such parameters, interesting (heretofore unseen) patterns are enabled. The hallmark of these phenomena is an endless squeezing and expansion of the particle formations along the direction of the temperature gradient. As confirmed by the numerical simulations, the underlying formation mechanisms rely on the combined action of the body force acting on particles due to their different density with respect to the host fluid and the additional drag that is produced when the carrier thermovibrational flow enters a specific stage, known as "convective burst", where the magnitude of the fluid velocity increases dramatically.
γ≤3.4x10^{7}. It is shown that, while for relatively high values of St and/or γ, only degenerate states are obtained, where all particles collapse on planar structures, for intermediate values of such parameters, interesting (heretofore unseen) patterns are enabled. The hallmark of these phenomena is an endless squeezing and expansion of the particle formations along the direction of the temperature gradient. As confirmed by the numerical simulations, the underlying formation mechanisms rely on the combined action of the body force acting on particles due to their different density with respect to the host fluid and the additional drag that is produced when the carrier thermovibrational flow enters a specific stage, known as "convective burst", where the magnitude of the fluid velocity increases dramatically.
Original language  English 

Article number  023323 
Number of pages  24 
Journal  Physics of Fluids 
Volume  35 
Issue number  2 
Early online date  30 Jan 2023 
DOIs  
Publication status  Published  21 Feb 2023 
Keywords
 thermovibrational convection
 particle selforganization
 numerical simulation
 EulerianLagrangian approach
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Dive into the research topics of 'Threedimensional solid particle selfassembly in thermovibrational flow: the case with unidirectional temperature gradient and concurrent vibrations'. Together they form a unique fingerprint.Projects
 4 Finished

Particles & Fluids for SpX26
STFC Science and Technology Facilities Council
1/01/22 → 31/08/23
Project: Research

Mixture Degassing for Flight Experiment
STFC Science and Technology Facilities Council
1/06/21 → 31/03/22
Project: Research

Particle Vibration ESR Finalisation
STFC Science and Technology Facilities Council
1/10/20 → 31/03/21
Project: Research
Datasets

Supplementary material for: ''Threedimensional Solid Particle Selfassembly in Thermovibrational Flow: The case with Unidirectional Temperature gradient and Concurrent Vibrations ''
Crewdson, G. (Creator) & Lappa, M. (Creator), University of Strathclyde, 30 Jan 2023
DOI: 10.15129/ec6c0bec0cbc44eaa9c03e345d9ec645
Dataset