Flow of colloidal suspensions through small orifices
Autor: | A. Hernández-Puerta, Ignacio Pagonabarraga, A. Goñi-Arana, Raúl Cruz Hidalgo |
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Přispěvatelé: | Universitat de Barcelona |
Rok vydání: | 2018 |
Předmět: |
Pressure drop
Col·loides Work (thermodynamics) Materials science Advection Suspensions (Chemistry) Flow (psychology) 02 engineering and technology Mechanics 021001 nanoscience & nanotechnology 01 natural sciences Suspension (chemistry) Clogging Physics::Fluid Dynamics 0103 physical sciences Particle Suspensions (Química) Particle velocity Colloids 010306 general physics 0210 nano-technology Área Física y Ciencias del Espacio |
Zdroj: | Dadun. Depósito Académico Digital de la Universidad de Navarra instname Recercat. Dipósit de la Recerca de Catalunya Dipòsit Digital de la UB Universidad de Barcelona |
Popis: | In this work, we numerically study a dense colloidal suspension flowing through a small outlet driven by a pressure drop using lattice-Boltzmann methods. This system shows intermittent flow regimes that precede clogging events. Several pieces of evidence suggest that the temperature controls the dynamic state of the system when the driving force and the aperture size are fixed. When the temperature is low, the suspension's flow can be interrupted during long time periods, which can be even two orders of magnitude larger than the system's characteristic time (Stokes). We also find that strong thermal noise does not allow the formation of stable aggregate structures avoiding extreme clogging events, but, at the same time, it randomizes the particle trajectories and disturbs the advective particle flow through the aperture. Moreover, examining the particle velocity statistics, we obtain that in the plane normal to the pressure drop the colloids always move as free particles regardless of the temperature value. In the pressure drop direction, at high temperature the colloids experience a simple balance between advective and diffusive transport, but at low temperature the nature of the flow is much more complex, correlating with the occurrence of very long clogging events. |
Databáze: | OpenAIRE |
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