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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 ClimatiqueTags : Génie Climatique: Thermique de bâtiment et réfrigération 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 انتقال الحرارة و الكتلة الاوساط المسامية جدار بسيط جدار متعدد الطبقات الحجوم المتناهية شروط حدية متغيرة Index. décimale : 626 Génie Climatique 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 : 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 [Algérie] : Université Constantine 1, 2014 . - 114 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie ClimatiqueTags : Génie Climatique: Thermique de bâtiment et réfrigération 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 انتقال الحرارة و الكتلة الاوساط المسامية جدار بسيط جدار متعدد الطبقات الحجوم المتناهية شروط حدية متغيرة Index. décimale : 626 Génie Climatique 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 : 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 Approche numérique de la convection naturelle thermo-solutale dans une cavité rectangulaire poreuse saturée de fluide et à orientation variable. / Abdelhakim Latreche
Titre : Approche numérique de la convection naturelle thermo-solutale dans une cavité rectangulaire poreuse saturée de fluide et à orientation variable. Type de document : texte imprimé Auteurs : Abdelhakim Latreche, Auteur ; Mahfoud Djezzar, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 101 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Physique Energétique: Photothermique Transfert de chaleur et de masse milieux poreux convection naturelle Double
diffusion modèle de Darcy-Brinkmann-Forchheimer volumes finis Heat and mass transfer porous media natural convection Double diffusion Darcy-Brinkmann-Forchheimer model finite volumes انتقال الحرارة والكتلة الوسائط المسامية الحمل الحراري الانتشار المزدوج نموذج دارسي
برينكمان-فورخايمر الحجوم المتناهيةIndex. décimale : 530 Physique Résumé :
In this thesis, heat and mass transfers by natural convection in porous media have been studied numerically. The horizontal walls are subjected to constant temperatures and impermeable to solute transport in the first case and at constant temperatures and
concentrations in the second case, while the vertical walls are thermally insulated and are subjected to constant concentrations in the first case, and are considered adiabatic in the second case. The phenomenon of thermo-solutal convection is governed by the conservation equations of mass, momentum, energy and concentration. The porous media are modeled according to the general model of Darcy and Darcy-Brinkman-Forchheimer respectively. The convective flow is governed by different control parameters, namely the angle of inclination (α ), the Rayleigh number (Ra), the ratio of the forces of volume (N), the number of Prandtl (Pr),the number of Lewis (Le), the Darcy number (Da) the form factor (A) and the porosity ε of the porous matrix. The finite volume method was used to solve the basic equations in porous media. Regarding the validation of the calculation code, the agreement obtained between our results and those available in the literature proved to be excellent. The influence of physical and geometrical parameters is examined. In the first case, five solutions characterized by multicellular and single-cell clockwise / counterclockwise, natural / antinatural flows were obtained in the case of the intermediate regime with the variation of the inclination, the structure of the flow intensifies and the transfers of Heat and average mass increase as │N│ increases. In the second case, two solutions characterized by multicellular (-90° ≤α≤0°) and single-cell trigonometric (0°<α≤90°) flows were obtained, the intensity of the flow decreases with increasing of α in both directions, while there was an increase in heat transfer and mass up to inclination 45° and 60° respectively. The structure of the flow intensifies and the average heat and mass transfers increase with the increase of N, Ra and A while the contrary has been found with Le except the mass transfer which keeps its increase.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/LAT7514.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11353 Approche numérique de la convection naturelle thermo-solutale dans une cavité rectangulaire poreuse saturée de fluide et à orientation variable. [texte imprimé] / Abdelhakim Latreche, Auteur ; Mahfoud Djezzar, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 101 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Physique Energétique: Photothermique Transfert de chaleur et de masse milieux poreux convection naturelle Double
diffusion modèle de Darcy-Brinkmann-Forchheimer volumes finis Heat and mass transfer porous media natural convection Double diffusion Darcy-Brinkmann-Forchheimer model finite volumes انتقال الحرارة والكتلة الوسائط المسامية الحمل الحراري الانتشار المزدوج نموذج دارسي
برينكمان-فورخايمر الحجوم المتناهيةIndex. décimale : 530 Physique Résumé :
In this thesis, heat and mass transfers by natural convection in porous media have been studied numerically. The horizontal walls are subjected to constant temperatures and impermeable to solute transport in the first case and at constant temperatures and
concentrations in the second case, while the vertical walls are thermally insulated and are subjected to constant concentrations in the first case, and are considered adiabatic in the second case. The phenomenon of thermo-solutal convection is governed by the conservation equations of mass, momentum, energy and concentration. The porous media are modeled according to the general model of Darcy and Darcy-Brinkman-Forchheimer respectively. The convective flow is governed by different control parameters, namely the angle of inclination (α ), the Rayleigh number (Ra), the ratio of the forces of volume (N), the number of Prandtl (Pr),the number of Lewis (Le), the Darcy number (Da) the form factor (A) and the porosity ε of the porous matrix. The finite volume method was used to solve the basic equations in porous media. Regarding the validation of the calculation code, the agreement obtained between our results and those available in the literature proved to be excellent. The influence of physical and geometrical parameters is examined. In the first case, five solutions characterized by multicellular and single-cell clockwise / counterclockwise, natural / antinatural flows were obtained in the case of the intermediate regime with the variation of the inclination, the structure of the flow intensifies and the transfers of Heat and average mass increase as │N│ increases. In the second case, two solutions characterized by multicellular (-90° ≤α≤0°) and single-cell trigonometric (0°<α≤90°) flows were obtained, the intensity of the flow decreases with increasing of α in both directions, while there was an increase in heat transfer and mass up to inclination 45° and 60° respectively. The structure of the flow intensifies and the average heat and mass transfers increase with the increase of N, Ra and A while the contrary has been found with Le except the mass transfer which keeps its increase.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/LAT7514.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11353 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité LAT/7514 LAT/7514 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 انتقال الحرارة والكتلة الوسط النافذ المتباين الخواص الحمل الحراري
الطبيعي نموذج دارسي- برينكمان- فورخايمر الأحجام المتناهيةIndex. 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 : 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 [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 انتقال الحرارة والكتلة الوسط النافذ المتباين الخواص الحمل الحراري
الطبيعي نموذج دارسي- برينكمان- فورخايمر الأحجام المتناهيةIndex. 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 : 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 : Simulation numérique de la convection naturelle dans une cavité carrée poreuse Type de document : texte imprimé Auteurs : Esma Belahmadi, Auteur ; Smail Benissaad, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 84 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : Natural convection finite volumes porous medium Convection naturelle Volumes finis Milieu poreux الحمل الحراري الطبیعي كمیات محدودة والمتوسطة التي يسهل اختراقها Index. décimale : 620 Génie Mécanique Résumé : In this work, we present a numerical study of two-dimensional and steady flow of a fluid generated by a temperature gradient in a porous square cavity. The vertical walls of the enclosure are maintained isotherms, whose left wall at a warm temperature (Th) and the
right wall at a cold temperature (Tc), while the horizontal walls (upper and lower) are adiabatic. A Fortran code based on the finite volume method and the SIMPLER algorithm was used to solve the equations that govern physical phenomena. The results are validated with previous results found in the literature, and presented in graphical form. The effects of the Grashof Gr, Darcy Da and Prandlt Pr numbers, porosity e, size and position of the heat source are studied. The results show that increasing the dimensionless parameters (Gr,Da, Pr, e) improve the heat transfer rate, but increase the entropy generation in the cavity.
Also, the Nusselt number is higher for a length greater of the heater, contrary, the total entropy is low when the size of the heating element is small. Finally, the heat transfer rate in the cavity is much higher in the case where the position of the heat source is in the middle of
the wall, but the total entropy is small when the heat source is positioned in the section of the upper wall.Diplôme : Magistère En ligne : ../theses/gmecanique/BEL6418.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9452 Simulation numérique de la convection naturelle dans une cavité carrée poreuse [texte imprimé] / Esma Belahmadi, Auteur ; Smail Benissaad, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2013 . - 84 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : Natural convection finite volumes porous medium Convection naturelle Volumes finis Milieu poreux الحمل الحراري الطبیعي كمیات محدودة والمتوسطة التي يسهل اختراقها Index. décimale : 620 Génie Mécanique Résumé : In this work, we present a numerical study of two-dimensional and steady flow of a fluid generated by a temperature gradient in a porous square cavity. The vertical walls of the enclosure are maintained isotherms, whose left wall at a warm temperature (Th) and the
right wall at a cold temperature (Tc), while the horizontal walls (upper and lower) are adiabatic. A Fortran code based on the finite volume method and the SIMPLER algorithm was used to solve the equations that govern physical phenomena. The results are validated with previous results found in the literature, and presented in graphical form. The effects of the Grashof Gr, Darcy Da and Prandlt Pr numbers, porosity e, size and position of the heat source are studied. The results show that increasing the dimensionless parameters (Gr,Da, Pr, e) improve the heat transfer rate, but increase the entropy generation in the cavity.
Also, the Nusselt number is higher for a length greater of the heater, contrary, the total entropy is low when the size of the heating element is small. Finally, the heat transfer rate in the cavity is much higher in the case where the position of the heat source is in the middle of
the wall, but the total entropy is small when the heat source is positioned in the section of the upper wall.Diplôme : Magistère En ligne : ../theses/gmecanique/BEL6418.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9452 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEL/6418 BEL/6418 Thèse Bibliothèque principale Thèses Disponible Documents numériques
texte intégraleAdobe Acrobat PDF
