| Title: |
Numerical simulation and physical analysis of the dispersion of charged inertial particles transported by stationary homogeneous isotropic turbulence ; Simulation numérique et analyse physique de la dispersion de particules inertielles chargées transportées par un écoulement turbulent homogène isotrope stationnaire |
| Authors: |
Boutsikakis, Athanasios |
| Contributors: |
Institut de mécanique des fluides de Toulouse (IMFT); Université Toulouse III - Paul Sabatier (UT3); Communauté d'universités et établissements de Toulouse (Comue de Toulouse)-Communauté d'universités et établissements de Toulouse (Comue de Toulouse)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP); Communauté d'universités et établissements de Toulouse (Comue de Toulouse); Institut National Polytechnique de Toulouse - INPT; Pascal Fede; Olivier Simonin |
| Source: |
https://theses.hal.science/tel-04193612 ; Fluid Dynamics [physics.flu-dyn]. Institut National Polytechnique de Toulouse - INPT, 2020. English. ⟨NNT : 2020INPT0097⟩. |
| Publisher Information: |
CCSD |
| Publication Year: |
2020 |
| Collection: |
Université Toulouse III - Paul Sabatier: HAL-UPS |
| Subject Terms: |
Concentration préférentielle; Dispersion; Théorie de Tchen-Hinze; Interaction particule-turbulence; Electrostatic interaction; Interaction électrostatique; [PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn] |
| Description: |
In this work, we study by numerical simulation the effect of electric charges on the dispersion of particles transported by a turbulent flow. The Navier-Stokes equations are solved by Direct Numerical Simulations (spectral approach) coupled with a Lagrangian solver in order to calculate the trajectories of each particle. A stochastic forcing scheme allows to obtain statistically homogeneous, isotropic and stationary turbulent flows. In the thesis, an original method to take into account electrostatic forces has been developed and validated on elementary configurations. In this method, the short-range interactions are estimated via a sum of the inter-particle interactions inside a cut-off distance and the long-range ones via a sum of interactions of particles with groups of particles which, at a distance greater than the cut-off distance, are considered as pseudo-particles. The convergence, the precision and the computational cost of the method have been studied in detail for its implementation for tri-periodic domains. The ensemble of these developments has been carried out in a parallel code which allows to perform simulations on a supercomputer of gas-particle flows containing up to 2 \times 10 5 particles. Firstly, the analysis of dry granular flows allowed to define a characteristic time scale of the effect of electric charges and to link it to the physical properties of the particles, in particular their diameter and agitation. The mechanism of transformation of the electric potential energy into particle kinetic energy is analyzed according to this time scale. Secondly, simulations of homogeneous isotropic turbulence transporting like-charged particles were carried out by varying their diameter (dynamic Stokes number) and their charge (electrostatic Stokes number). The simulations show that, for a given dynamic Stokes, the increase in particle charge leads to a decrease in their agitation since the electrostatic (repulsive) forces are conservative. The detailed analysis shows that, in fact, the ... |
| Document Type: |
doctoral or postdoctoral thesis |
| Language: |
English |
| Relation: |
NNT: 2020INPT0097 |
| Availability: |
https://theses.hal.science/tel-04193612; https://theses.hal.science/tel-04193612v1/document; https://theses.hal.science/tel-04193612v1/file/Boutsikakis_Athanasios.pdf |
| Rights: |
https://about.hal.science/hal-authorisation-v1/ ; info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.C8CDAD86 |
| Database: |
BASE |