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Titre : Approches numériques par des volumes finis d’une équation de transport Type de document : texte imprimé Auteurs : Lakhdar Kassah Laouar, Auteur ; Fateh El Lagoune, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2012 Importance : 89 f. Format : 31 cm. Note générale : Magister
2 copies imprimées disponiblesLangues : Français (fre) Catégories : Français - Anglais
MathématiquesTags : Modélisation mathématique equation de transport lois de conservation Différences finies volumes finis approches algorithmiques estimations d’erreur vitesse de convergence simulations numériques Index. décimale : 510 Mathématiques Diplôme : Magistère En ligne : ../theses/math/KAS6213.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=6166 Approches numériques par des volumes finis d’une équation de transport [texte imprimé] / Lakhdar Kassah Laouar, Auteur ; Fateh El Lagoune, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2012 . - 89 f. ; 31 cm.
Magister
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
MathématiquesTags : Modélisation mathématique equation de transport lois de conservation Différences finies volumes finis approches algorithmiques estimations d’erreur vitesse de convergence simulations numériques Index. décimale : 510 Mathématiques Diplôme : Magistère En ligne : ../theses/math/KAS6213.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=6166 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KAS/6213 KAS/6213 Thèse Bibliothèque principale Thèses Disponible Étude Numérique des écoulements thermoconvectifs d’un nanofluide à travers un espace cylindrique annulaire muni d’ailettes / Mohammed Benkhedda
Titre : Étude Numérique des écoulements thermoconvectifs d’un nanofluide à travers un espace cylindrique annulaire muni d’ailettes Type de document : texte imprimé Auteurs : Mohammed Benkhedda, Auteur ; Toufik Boufendi, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 251 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Nanofluide Convection mixte Cylindre annulaire horizontal Monophasique Ailettes longitudinales Nanofluide hybride Volumes finis Nanofluid Mixed convection Horizontal annular cylinder Single phase longitudinal fins Hybrid nanofluid Finite volume ??? ????? ????? ??????? ?????? ??????? ????? ????? ????? ????? ???? ?????
???? ?????? ????????Index. décimale : 530 Physique Résumé : The doctoral project concerns a three-dimensional numerical study of the thermo-convective flows of a nanofluid through an annular cylindrical space without fin and equipped with fins. Newtonian, incompressible and laminar flow with temperature dependent physical properties. The single-phase approach is adopted. The outer cylinder is uniformly heated while the inner cylinder is adiabatic. The flow and thermal fields are modeled by the continuity equation, the three momentum equations and the energy equation of the nanofluid with appropriate initial and boundary conditions using a cylindrical coordinate system. The nonlinear differential equations with partial derivatives are solved numerically by the finite volume method with a spatio-temporal discretization of the second order. The SIMPLER algorithm was used to solve the speed-pressure coupling. A complete parametric analysis on the effect of the presence of nanoparticles dispersed in the fluid such as volume fraction, type and shape on the development of thermal and hydrodynamic fields. The dimensionless control parameters that control the problem under consideration are the Reynolds number, the Prandtl number and the Grashof number, a radius ratio set to 2. For the volume fraction ranging from 0 to 10%, six nanoparticles Types, two metallic types Cu and Ag, three ceramics Al2O3, TiO2 and CuO. Also four forms of the nanoparticles are the shape the spherical shape, Blade, Cylinder, Platelet and Bricks shape. The study of these effects on heat transfer in a annular cylinder without fins and with fins is the main objective of this study. The results concerning the different cases studied for the effect of the volume fraction of the different nanofluids shows that the increase in the volume fraction increases the heat transfer along the annular duct. The axial and mean Nusselt numbers obtained are also higher in the case of the nanofluid (Ag / water). They also show that the use of the Ag nanoparticle induces a better improvement of the heat transfer followed by Cu, Al2O3, CuO at the end TiO2. Regarding the effect of the shape of the nanoparticles Blade shape greatly improves the heat transfer compared to other shapes. A generating correlation expresses the average Nusselt number for the different shapes as a function of the volume fraction proposed: Nu moy = a + bϕ + cϕ2. Another correlation which expresses the average Nusselt number of the nanofluid (TiO2/water) and the hybrid nanofluid (Ag-TiO2 / water) as a function of the number of Grashof, Prandtl and the volume fraction: The use of the heat-generating fins, attached longitudinally to the outer cylinder and immersed in the nanofluid, greatly improves the heat transfer compared to those of a nonfinned horizontal duct dû to the increase in the exchange area between The nanofluid and the fins in the annular space.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/BOU7334.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10984 Étude Numérique des écoulements thermoconvectifs d’un nanofluide à travers un espace cylindrique annulaire muni d’ailettes [texte imprimé] / Mohammed Benkhedda, Auteur ; Toufik Boufendi, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2018 . - 251 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Nanofluide Convection mixte Cylindre annulaire horizontal Monophasique Ailettes longitudinales Nanofluide hybride Volumes finis Nanofluid Mixed convection Horizontal annular cylinder Single phase longitudinal fins Hybrid nanofluid Finite volume ??? ????? ????? ??????? ?????? ??????? ????? ????? ????? ????? ???? ?????
???? ?????? ????????Index. décimale : 530 Physique Résumé : The doctoral project concerns a three-dimensional numerical study of the thermo-convective flows of a nanofluid through an annular cylindrical space without fin and equipped with fins. Newtonian, incompressible and laminar flow with temperature dependent physical properties. The single-phase approach is adopted. The outer cylinder is uniformly heated while the inner cylinder is adiabatic. The flow and thermal fields are modeled by the continuity equation, the three momentum equations and the energy equation of the nanofluid with appropriate initial and boundary conditions using a cylindrical coordinate system. The nonlinear differential equations with partial derivatives are solved numerically by the finite volume method with a spatio-temporal discretization of the second order. The SIMPLER algorithm was used to solve the speed-pressure coupling. A complete parametric analysis on the effect of the presence of nanoparticles dispersed in the fluid such as volume fraction, type and shape on the development of thermal and hydrodynamic fields. The dimensionless control parameters that control the problem under consideration are the Reynolds number, the Prandtl number and the Grashof number, a radius ratio set to 2. For the volume fraction ranging from 0 to 10%, six nanoparticles Types, two metallic types Cu and Ag, three ceramics Al2O3, TiO2 and CuO. Also four forms of the nanoparticles are the shape the spherical shape, Blade, Cylinder, Platelet and Bricks shape. The study of these effects on heat transfer in a annular cylinder without fins and with fins is the main objective of this study. The results concerning the different cases studied for the effect of the volume fraction of the different nanofluids shows that the increase in the volume fraction increases the heat transfer along the annular duct. The axial and mean Nusselt numbers obtained are also higher in the case of the nanofluid (Ag / water). They also show that the use of the Ag nanoparticle induces a better improvement of the heat transfer followed by Cu, Al2O3, CuO at the end TiO2. Regarding the effect of the shape of the nanoparticles Blade shape greatly improves the heat transfer compared to other shapes. A generating correlation expresses the average Nusselt number for the different shapes as a function of the volume fraction proposed: Nu moy = a + bϕ + cϕ2. Another correlation which expresses the average Nusselt number of the nanofluid (TiO2/water) and the hybrid nanofluid (Ag-TiO2 / water) as a function of the number of Grashof, Prandtl and the volume fraction: The use of the heat-generating fins, attached longitudinally to the outer cylinder and immersed in the nanofluid, greatly improves the heat transfer compared to those of a nonfinned horizontal duct dû to the increase in the exchange area between The nanofluid and the fins in the annular space.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/BOU7334.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10984 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/7334 BEN/7334 Thèse Bibliothèque principale Thèses Disponible
Titre : Diffusion thermo-hydrique dans les materiaux de construction Type de document : texte imprimé Auteurs : Fouad Fergati, Auteur ; Azeddine Belhamri, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2014 Importance : 114 f Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie CivilTags : "Transfert de chaleur et de masse Milieu poreux Paroi simple Paroi multicouche Volumes finis Conditions aux limites variables "
"Heat and mass transfer Simple wall Multilayered wall Finite volumes Variable boundary conditions."
?????? ??????? ? ?????? -??????? ????????- ???? ????- ???? ????? ???????-?????? ?????????- ???? ???? ??????.Index. décimale : 624 Génie civil Résumé : "The present study concerns coupled mass and thermal transfers in tow simple and
multilayered walls, by using constant and variable boundary conditions.
The thermal mechanism transfer is presumed by conduction and that of mass is assumed by
diffusion. We have adopted thermal conductivity and mass diffusivity which are variable and are
functions of water content. Temperature, moisture content, thermal and mass flux continuity is
used at the level of layer contact surfaces for multilayered wall.
To better know the influence of the variation of the outside conditions on the behavior of the
thermal transfer and the evolution of the temperature in the wall. We have adopted external
boundary conditions as periodic and sinusoidal form. In order to be much closer from reality, we
have studied the transfers in a simple wall made of concrete and in another one which is
multilayered.
Basing on finite volumes method, some simulations have been realized, using a code of
calculation by Fortran 90. The results are validated by comparing them with other studies
recently published. They show that:
- The transfer coefficients are strongly coupled, and the physical medium
characteristics make the thermal transfer unsteady.
- The boundary conditions strongly influence the evolution of the temperature in the
wall and also the thermal flux densities at the level of wall interior surface."
Diplôme : Magistère En ligne : ../theses/gclim/FER6507.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9606 Diffusion thermo-hydrique dans les materiaux de construction [texte imprimé] / Fouad Fergati, Auteur ; Azeddine Belhamri, Directeur de thèse . - constantine (Route ain el bey, Algérie) : Université Constantine 1, 2014 . - 114 f ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie CivilTags : "Transfert de chaleur et de masse Milieu poreux Paroi simple Paroi multicouche Volumes finis Conditions aux limites variables "
"Heat and mass transfer Simple wall Multilayered wall Finite volumes Variable boundary conditions."
?????? ??????? ? ?????? -??????? ????????- ???? ????- ???? ????? ???????-?????? ?????????- ???? ???? ??????.Index. décimale : 624 Génie civil Résumé : "The present study concerns coupled mass and thermal transfers in tow simple and
multilayered walls, by using constant and variable boundary conditions.
The thermal mechanism transfer is presumed by conduction and that of mass is assumed by
diffusion. We have adopted thermal conductivity and mass diffusivity which are variable and are
functions of water content. Temperature, moisture content, thermal and mass flux continuity is
used at the level of layer contact surfaces for multilayered wall.
To better know the influence of the variation of the outside conditions on the behavior of the
thermal transfer and the evolution of the temperature in the wall. We have adopted external
boundary conditions as periodic and sinusoidal form. In order to be much closer from reality, we
have studied the transfers in a simple wall made of concrete and in another one which is
multilayered.
Basing on finite volumes method, some simulations have been realized, using a code of
calculation by Fortran 90. The results are validated by comparing them with other studies
recently published. They show that:
- The transfer coefficients are strongly coupled, and the physical medium
characteristics make the thermal transfer unsteady.
- The boundary conditions strongly influence the evolution of the temperature in the
wall and also the thermal flux densities at the level of wall interior surface."
Diplôme : Magistère En ligne : ../theses/gclim/FER6507.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9606 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité FER/6507 FER/6507 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude de la convection bidiffusive dans un milieu poreux anisotrope Type de document : texte imprimé Auteurs : Safia Safi, Auteur ; Smail Benissaad, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 88 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
Génie ClimatiqueTags : Transfert de chaleur et masse milieux poreux anisotropes convection naturelle modèle de Darcy?Brinkmann? Forchheimer volumes finis Heat and mass transfer anisotropic porous media convection model of Darcy?Brinkman?Forchheimer finite volumes ?????? ??????? ??????? ????? ?????? ???????? ?????? ????? ???????
??????? ????? ?????- ????????- ???????? ??????? ?????????Index. décimale : 626 Génie Climatique Résumé : The phenomenon of the natural convection in porous anisotropic media has been studied by several authors because of its importance in many industrial applications.
The literature shows that the studies of heat and mass transfer induced by thermosolutal convection in an anisotropic porous medium are few compared to those of natural convection in isotropic media.
It is in this context that our present work is part. It is to study the two‐dimensional problem of thermosolutal natural convection within an anisotropic porous medium saturated by a binary fluid, assumed to be incompressible, confined within a horizontal rectangular enclosure. The vertical walls of the cavity are subjected to constant temperatures and concentrations (boundary conditions of Dirichlet), while the horizontal walls are kept waterproof and adiabati . The convective flow is governed by different control parameters, namely the Darcy number, the Rayleigh number, the ratio of volume forces, the Lewis number, and the aspect ratio of the cavity.
The conservation equations of mass, momentum, energy and concentration were derived taking into account the Boussinesq approximation. The mathematical model used is the Darcy‐Brinkman‐Forchheimer. A numerical code based on the finite volume method was developed to solve the basic equations in anisotropic saturated porous medium.
The influence of parameters such as the anisotropy in thermal conductivity and the anisotropy in permeability on the transfer of heat and mass and on the flow structures were analyzed. The results are validated by comparison with previous work reported in the literature. A satisfactory agreement was observed. The parametric study involved the aspect ratio of the cavity, the Darcy number that characterizes the permeability of the medium, the thermal Rayleigh number, which characterizes the deviation of the temperature, the ratio of volume forces and the number of Lewis which characterizes the ratio of thermal and solutal diffusions on the evolution of flow structures and heat and mass transfer.
It was concluded that the thermal anisotropy affect significantly transfers in different situations. The numerical solution shows that for high volume forces, mass transfer is the vi same regardless of the conductivity ratio. The ratio of volume forces has no effect on the
heat transfer.
The study of the influence of anisotropy in permeability rate on transfers identified two flow regimes. A fully convective and the other moderately convective.
The comparison between Darcy model and Darcy‐Brinkman‐Forchheimer model has also allowed highlighting: Identification of three transfer zones; flow and heat and mass transfer are proportional to Darcy number; heat and mass transfer increase with Rayleigh number; the appearance of two secondary convection cells inside the main flow at low values of Rayleigh number; the anisotropy in permeability causes thermal anisotropy; the occurrence of two side convection cells within Master for low values of the Rayleigh number flow, and the permeability anisotropy leads to anisotropy and thermal and vice versa.Diplôme : Doctorat en sciences En ligne : ../theses/gclim/SAF6423.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9447 Etude de la convection bidiffusive dans un milieu poreux anisotrope [texte imprimé] / Safia Safi, Auteur ; Smail Benissaad, Directeur de thèse . - constantine (Route ain el bey, Algérie) : Université Constantine 1, 2013 . - 88 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie ClimatiqueTags : Transfert de chaleur et masse milieux poreux anisotropes convection naturelle modèle de Darcy?Brinkmann? Forchheimer volumes finis Heat and mass transfer anisotropic porous media convection model of Darcy?Brinkman?Forchheimer finite volumes ?????? ??????? ??????? ????? ?????? ???????? ?????? ????? ???????
??????? ????? ?????- ????????- ???????? ??????? ?????????Index. décimale : 626 Génie Climatique Résumé : The phenomenon of the natural convection in porous anisotropic media has been studied by several authors because of its importance in many industrial applications.
The literature shows that the studies of heat and mass transfer induced by thermosolutal convection in an anisotropic porous medium are few compared to those of natural convection in isotropic media.
It is in this context that our present work is part. It is to study the two‐dimensional problem of thermosolutal natural convection within an anisotropic porous medium saturated by a binary fluid, assumed to be incompressible, confined within a horizontal rectangular enclosure. The vertical walls of the cavity are subjected to constant temperatures and concentrations (boundary conditions of Dirichlet), while the horizontal walls are kept waterproof and adiabati . The convective flow is governed by different control parameters, namely the Darcy number, the Rayleigh number, the ratio of volume forces, the Lewis number, and the aspect ratio of the cavity.
The conservation equations of mass, momentum, energy and concentration were derived taking into account the Boussinesq approximation. The mathematical model used is the Darcy‐Brinkman‐Forchheimer. A numerical code based on the finite volume method was developed to solve the basic equations in anisotropic saturated porous medium.
The influence of parameters such as the anisotropy in thermal conductivity and the anisotropy in permeability on the transfer of heat and mass and on the flow structures were analyzed. The results are validated by comparison with previous work reported in the literature. A satisfactory agreement was observed. The parametric study involved the aspect ratio of the cavity, the Darcy number that characterizes the permeability of the medium, the thermal Rayleigh number, which characterizes the deviation of the temperature, the ratio of volume forces and the number of Lewis which characterizes the ratio of thermal and solutal diffusions on the evolution of flow structures and heat and mass transfer.
It was concluded that the thermal anisotropy affect significantly transfers in different situations. The numerical solution shows that for high volume forces, mass transfer is the vi same regardless of the conductivity ratio. The ratio of volume forces has no effect on the
heat transfer.
The study of the influence of anisotropy in permeability rate on transfers identified two flow regimes. A fully convective and the other moderately convective.
The comparison between Darcy model and Darcy‐Brinkman‐Forchheimer model has also allowed highlighting: Identification of three transfer zones; flow and heat and mass transfer are proportional to Darcy number; heat and mass transfer increase with Rayleigh number; the appearance of two secondary convection cells inside the main flow at low values of Rayleigh number; the anisotropy in permeability causes thermal anisotropy; the occurrence of two side convection cells within Master for low values of the Rayleigh number flow, and the permeability anisotropy leads to anisotropy and thermal and vice versa.Diplôme : Doctorat en sciences En ligne : ../theses/gclim/SAF6423.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9447 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité SAF/6423 SAF/6423 Thèse Bibliothèque principale Thèses Disponible Documents numériques
texte intégraleAdobe Acrobat PDF
Titre : Modélisation de mécanismes se produisant dans un plasma de dépôt Type de document : texte imprimé Auteurs : Amal Berkane, Auteur ; Saida Benahmed-Rebiai, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2015 Importance : 137 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : microplasma microréacteur volumes finis microdécharge cathode creuse Comsol microreactor finite volume microdischarge hollow cathode ??????????? ?????????? ??? ????? ???? ???? Index. décimale : 621 Electronique Résumé : The present work is to develop a single and multi-dimensional numerical model to describe the transport phenomena of charged and excited species in a cold plasma microreactor. For that, we first developed a simple fluid model using the drift and diffusion approximation containing only the ionization
process in continuous mode and simulated by the finite volume method written in FORTRAN code. Eventually we developed this model by exploiting the commercial software Comsol, for a digital micro-hollow cathode discharge study submitted to radiofrequency excitation. The two dimensional simulation
performed allowed us to do a study on the effect of control parameters, such as pressure, gaz temperature and frequency on the change in the electron density , the electron temperature , potential, and reaction rates of various chemical process.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BER6799.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10041 Modélisation de mécanismes se produisant dans un plasma de dépôt [texte imprimé] / Amal Berkane, Auteur ; Saida Benahmed-Rebiai, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2015 . - 137 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : microplasma microréacteur volumes finis microdécharge cathode creuse Comsol microreactor finite volume microdischarge hollow cathode ??????????? ?????????? ??? ????? ???? ???? Index. décimale : 621 Electronique Résumé : The present work is to develop a single and multi-dimensional numerical model to describe the transport phenomena of charged and excited species in a cold plasma microreactor. For that, we first developed a simple fluid model using the drift and diffusion approximation containing only the ionization
process in continuous mode and simulated by the finite volume method written in FORTRAN code. Eventually we developed this model by exploiting the commercial software Comsol, for a digital micro-hollow cathode discharge study submitted to radiofrequency excitation. The two dimensional simulation
performed allowed us to do a study on the effect of control parameters, such as pressure, gaz temperature and frequency on the change in the electron density , the electron temperature , potential, and reaction rates of various chemical process.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BER6799.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10041 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BER/6799 BER/6799 Thèse Bibliothèque principale Thèses Disponible Permalink
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PermalinkContribution à l'étude de l'influence des conditions de surface sur les transferts thermo-hydriques dans les milieux poreux / Loubna Kahèerras
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