Résultat de la recherche
18 recherche sur le tag
'natural convection' 
Visionner les documents numériques
Affiner la recherche Générer le flux rss de la recherche
Partager le résultat de cette recherche Interroger des sources externes
Titre : Investigation des échanges convectifs dans diverses configurations Type de document : texte imprimé Auteurs : Issam Rezaiguia, Auteur ; Mahfoud Kadja, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2014 Importance : 142 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : convection naturelle nanofluides cavité triangulaire angle d'inclinaison simulation numérique microcanaux chute de pression transfert thermique conjugué fraction solide comportement non-Newtonien natural convection nanofluids triangular cavity inclination angle numerical simulation microchannels pressure drop conjugate heat transfer solid fraction non-Newtonian behavior الحمل الحراري الطبيعي مائع نانوي تجويف ثلاثي الشكل زاوية الميل محاكاة العددية قنوات ميكروية هبوط الضغط نقل الحرارة نسب الحيود للذرات الصلبة سلوك غير نيوتوني Index. décimale : 620 Génie Mécanique Résumé : This thesis reports the results of two studies: the first one concerns natural convection in isosceles triangular cavities with a partially active base while the second one concerns heat transfer in microchannels.
The first study considers natural convection cooling of a heat source located on the bottom wall of an inclined isosceles triangular enclosure filled with a Cu water-nanofluid. The right and left walls of the enclosure are both maintained cold at constant equal temperatures, while the remaining parts of the bottom wall are insulated. The study has been carried out for a Rayleigh number in the range 104 ≤ Ra ≤ 106, for a heat source length in the range 0.2 ≤ ε ≤ 0.8, for a solid volume fraction in the range 0.0 ≤ � ≤ 06 and for an inclination angle in the range 00 ≤ δ ≤ 450. Results are presented in the form of streamline contours, isotherms, maximum temperature at the heat source surface and average Nusselt number. It is noticed that the addition of Cu nanoparticles enhances the heat transfer rate and therefore cooling effectiveness for all values of Rayleigh number, especially at low values of Ra. The effect of the inclination angle becomes more noticeable as one increases the value of Ra. For high Rayleigh numbers, a critical value for the inclination angle of δ = 150 is found for which the heat source maximum temperature is highest.
The second study investigates heat transfer in microchannels machined in heat dissipating sinks. The fluid used is a nanofluid whose properties are temperature dependent. The energy dissipation is evaluated for various solid fraction contents along with the cooling effectiveness of this modern type of heat exchangers. The shape of the channels is also investigated. The evaluation parameter used for thermal energy dissipation is the Nusselt number while that used for cooling effectiveness is the static pressure drop between the inlet and the outlet of the microchannel. Conjugate convection-conduction energy conservation equations have been solved along with mass and momentum conservation equations in order to determine these parameters.
The results obtained showed important heat transfer augmentation with solid fraction at the expense of an increased pressure drop, i.e high pumping cost (therefore low cooling effectiveness). The microchannel inlet section geometry was also found to contribute to the values of the Nusselt number and pressure drop. Among the tested geometries (elliptical, rectangular, trapezoidal) the rectangular section provided the best compromise between heat transfer augmentation and pumping cost. At the end of the study, a comparison was made between the results obtained by assuming Newtonian rheology and those obtained with non-Newtonian rheological behavior of the same nanofluid sample. It was found that the assumption of non-Newtonian rheological behavior of nanofluids gives higher Nusselt number values and much lower pressure drops.
Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/REZ6773.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9837 Investigation des échanges convectifs dans diverses configurations [texte imprimé] / Issam Rezaiguia, Auteur ; Mahfoud Kadja, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2014 . - 142 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : convection naturelle nanofluides cavité triangulaire angle d'inclinaison simulation numérique microcanaux chute de pression transfert thermique conjugué fraction solide comportement non-Newtonien natural convection nanofluids triangular cavity inclination angle numerical simulation microchannels pressure drop conjugate heat transfer solid fraction non-Newtonian behavior الحمل الحراري الطبيعي مائع نانوي تجويف ثلاثي الشكل زاوية الميل محاكاة العددية قنوات ميكروية هبوط الضغط نقل الحرارة نسب الحيود للذرات الصلبة سلوك غير نيوتوني Index. décimale : 620 Génie Mécanique Résumé : This thesis reports the results of two studies: the first one concerns natural convection in isosceles triangular cavities with a partially active base while the second one concerns heat transfer in microchannels.
The first study considers natural convection cooling of a heat source located on the bottom wall of an inclined isosceles triangular enclosure filled with a Cu water-nanofluid. The right and left walls of the enclosure are both maintained cold at constant equal temperatures, while the remaining parts of the bottom wall are insulated. The study has been carried out for a Rayleigh number in the range 104 ≤ Ra ≤ 106, for a heat source length in the range 0.2 ≤ ε ≤ 0.8, for a solid volume fraction in the range 0.0 ≤ � ≤ 06 and for an inclination angle in the range 00 ≤ δ ≤ 450. Results are presented in the form of streamline contours, isotherms, maximum temperature at the heat source surface and average Nusselt number. It is noticed that the addition of Cu nanoparticles enhances the heat transfer rate and therefore cooling effectiveness for all values of Rayleigh number, especially at low values of Ra. The effect of the inclination angle becomes more noticeable as one increases the value of Ra. For high Rayleigh numbers, a critical value for the inclination angle of δ = 150 is found for which the heat source maximum temperature is highest.
The second study investigates heat transfer in microchannels machined in heat dissipating sinks. The fluid used is a nanofluid whose properties are temperature dependent. The energy dissipation is evaluated for various solid fraction contents along with the cooling effectiveness of this modern type of heat exchangers. The shape of the channels is also investigated. The evaluation parameter used for thermal energy dissipation is the Nusselt number while that used for cooling effectiveness is the static pressure drop between the inlet and the outlet of the microchannel. Conjugate convection-conduction energy conservation equations have been solved along with mass and momentum conservation equations in order to determine these parameters.
The results obtained showed important heat transfer augmentation with solid fraction at the expense of an increased pressure drop, i.e high pumping cost (therefore low cooling effectiveness). The microchannel inlet section geometry was also found to contribute to the values of the Nusselt number and pressure drop. Among the tested geometries (elliptical, rectangular, trapezoidal) the rectangular section provided the best compromise between heat transfer augmentation and pumping cost. At the end of the study, a comparison was made between the results obtained by assuming Newtonian rheology and those obtained with non-Newtonian rheological behavior of the same nanofluid sample. It was found that the assumption of non-Newtonian rheological behavior of nanofluids gives higher Nusselt number values and much lower pressure drops.
Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/REZ6773.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9837 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité REZ/6773 REZ/6773 Thèse Bibliothèque principale Thèses Disponible Transfert convectif dans une cavité totalement ou partiellement occupée par une matrice poreuse en ETL ou HETL / Abderrahim Bourouis
Titre : Transfert convectif dans une cavité totalement ou partiellement occupée par une matrice poreuse en ETL ou HETL Type de document : texte imprimé Auteurs : Abderrahim Bourouis, Auteur ; Abdeslam Omara, Auteur Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 131 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Physique Energétique Convection Mixte Conjuguée Convection Naturelle Milieu Poreux Hors Équilibre Thermique Local Phase Solide Phase Fluide Volumes Finis Conjugate Mixed Convection Natural Convection Porous Medium Local Thermal non Equilibrium Solid Phase Fluid Phase Finite-Volume Method حمل حراري مختلط حمل حراري طبیعي وسط مسامي عدم التوازن الحراري الموضعي طور مائع طور صلب الحجوم المنتھیة Index. décimale : 530 Physique Résumé : In this work, a numerical study of convective heat transfer in confined fluid and porous media was considered. The fluid flow is governed by the Navier–Stokes equations in the fluid region whereas the Darcy–Brinkman–Forchheimer model in the porous region. The finite volume method is used in order to discrete the governing equations, and the SIMPLE algorithm is used to treat the coupling pressure-velocity.
Initially, the first application is to examine the effects of the Richardson number (Ri = 0.1, 1, 10) and thermal conductivity ratio (Rk = 0.1, 1, 10, 100) on the heat transfer by conjugate mixed convection and conduction in a lid-driven enclosure with thick vertical porous layer. The left vertical moving wall of enclosure takes two different directions, (upward or downward moving wall). In this study, the compression of isotherms in the porous layer is observed at low conductivity ratio, while at large conductivity ratio, isotherms span the fluid filled part of the enclosure. It is also observed that average Nusselt numbers along the right hot wall and along the fluid-porous layer interface tend to zero at large and low thermal conductivity ratio, respectively.
For the second application, we have considered a thermal non-equilibrium approach on
natural convection in a square porous cavity with partial active vertical walls. Depending on the location of hot part and cold part, respectively on the left and right side walls, two cases are considered: Upper-Lower and Lower-Upper active walls. The two equations model is used to take into account separately local temperatures of the fluid and the solid. The effect of the Rayleigh number, Darcy number, inter-phase heat transfer coefficient and modified conductivity ratio is examined. The obtained results reveal that the location of the hot and cold parts on the vertical side walls has a significant influence on the flow structure and the rate of heat transfer within the enclosure.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/BOU6987.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10407 Transfert convectif dans une cavité totalement ou partiellement occupée par une matrice poreuse en ETL ou HETL [texte imprimé] / Abderrahim Bourouis, Auteur ; Abdeslam Omara, Auteur . - جامعة الإخوة منتوري قسنطينة, 2016 . - 131 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Physique Energétique Convection Mixte Conjuguée Convection Naturelle Milieu Poreux Hors Équilibre Thermique Local Phase Solide Phase Fluide Volumes Finis Conjugate Mixed Convection Natural Convection Porous Medium Local Thermal non Equilibrium Solid Phase Fluid Phase Finite-Volume Method حمل حراري مختلط حمل حراري طبیعي وسط مسامي عدم التوازن الحراري الموضعي طور مائع طور صلب الحجوم المنتھیة Index. décimale : 530 Physique Résumé : In this work, a numerical study of convective heat transfer in confined fluid and porous media was considered. The fluid flow is governed by the Navier–Stokes equations in the fluid region whereas the Darcy–Brinkman–Forchheimer model in the porous region. The finite volume method is used in order to discrete the governing equations, and the SIMPLE algorithm is used to treat the coupling pressure-velocity.
Initially, the first application is to examine the effects of the Richardson number (Ri = 0.1, 1, 10) and thermal conductivity ratio (Rk = 0.1, 1, 10, 100) on the heat transfer by conjugate mixed convection and conduction in a lid-driven enclosure with thick vertical porous layer. The left vertical moving wall of enclosure takes two different directions, (upward or downward moving wall). In this study, the compression of isotherms in the porous layer is observed at low conductivity ratio, while at large conductivity ratio, isotherms span the fluid filled part of the enclosure. It is also observed that average Nusselt numbers along the right hot wall and along the fluid-porous layer interface tend to zero at large and low thermal conductivity ratio, respectively.
For the second application, we have considered a thermal non-equilibrium approach on
natural convection in a square porous cavity with partial active vertical walls. Depending on the location of hot part and cold part, respectively on the left and right side walls, two cases are considered: Upper-Lower and Lower-Upper active walls. The two equations model is used to take into account separately local temperatures of the fluid and the solid. The effect of the Rayleigh number, Darcy number, inter-phase heat transfer coefficient and modified conductivity ratio is examined. The obtained results reveal that the location of the hot and cold parts on the vertical side walls has a significant influence on the flow structure and the rate of heat transfer within the enclosure.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/BOU6987.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10407 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/6987 BOU/6987 Thèse Bibliothèque principale Thèses Disponible
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 : Contribution à l’étude de la convection naturelle dans des enceintes à parois courbées remplies de nanofluides. Type de document : texte imprimé Auteurs : Abdelaziz Yahiaoui, Auteur ; Mahfoud Djezzar, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 147 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Physique Energétique: Photothermique convection naturelle nanofluides enceintes à parois courbées vorticité-fonction
de courant simulation numérique Natural convection Nanofluids enclosures with curved walls vorticity-Streamlines Numerical simulation الحمل الطبيعي النانوفلويد تجويف بجدران منحنية التدويم-دوال التيارات المحاكات العدديةIndex. décimale : 540 Chimie et sciences connexes Résumé :
In our investigation we have studied and compared the laminar and permanent natural convection in two-dimensional enclosures (square enclosure, enclosures with curved walls) filled with nanofluid (water-Cu) and subject to three different types of boundary conditions that are: first case (horizontal walls of enclosure are adiabatic, and vertical walls are isothermal maintained at cold temperature Tc and hot temperature Th), second case (vertical walls of enclosures are maintained isothermal at a cold temperature Tc, horizontal top walls are considered adiabatic and bottom walls are maintained isothermal at a constant hot temperature Th), third case (vertical walls of the enclosures are maintained isothermal at a cold temperature Tc, horizontal top walls are considered adiabatic and bottom walls are maintained at a sinusoidal hot temperature). We considered a Newtonian fluid and the flow is incompressible. The values of Rayleigh number are: 103, 104, 105 and 106, the Prandtl number is fixed to 6.2 and the volume fraction ϕ is taken equal to: 0, 0.1 and 0.2. The method used in this study is the finite volume method. The numerical results obtained show that the heat transfer rate increases both with increasing the volume fraction and the Rayleigh number, and that the average Nusselt number and therefore the heat transfer increases with the increase of the volume fraction of the nanoparticles for the full range of Rayleigh numbers, and that the effect of the nanofluid on natural convection is much more manifest for higher values of Rayleigh number.Note de contenu :
Annexes.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/YAH7521.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11360 Contribution à l’étude de la convection naturelle dans des enceintes à parois courbées remplies de nanofluides. [texte imprimé] / Abdelaziz Yahiaoui, Auteur ; Mahfoud Djezzar, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 147 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Physique Energétique: Photothermique convection naturelle nanofluides enceintes à parois courbées vorticité-fonction
de courant simulation numérique Natural convection Nanofluids enclosures with curved walls vorticity-Streamlines Numerical simulation الحمل الطبيعي النانوفلويد تجويف بجدران منحنية التدويم-دوال التيارات المحاكات العدديةIndex. décimale : 540 Chimie et sciences connexes Résumé :
In our investigation we have studied and compared the laminar and permanent natural convection in two-dimensional enclosures (square enclosure, enclosures with curved walls) filled with nanofluid (water-Cu) and subject to three different types of boundary conditions that are: first case (horizontal walls of enclosure are adiabatic, and vertical walls are isothermal maintained at cold temperature Tc and hot temperature Th), second case (vertical walls of enclosures are maintained isothermal at a cold temperature Tc, horizontal top walls are considered adiabatic and bottom walls are maintained isothermal at a constant hot temperature Th), third case (vertical walls of the enclosures are maintained isothermal at a cold temperature Tc, horizontal top walls are considered adiabatic and bottom walls are maintained at a sinusoidal hot temperature). We considered a Newtonian fluid and the flow is incompressible. The values of Rayleigh number are: 103, 104, 105 and 106, the Prandtl number is fixed to 6.2 and the volume fraction ϕ is taken equal to: 0, 0.1 and 0.2. The method used in this study is the finite volume method. The numerical results obtained show that the heat transfer rate increases both with increasing the volume fraction and the Rayleigh number, and that the average Nusselt number and therefore the heat transfer increases with the increase of the volume fraction of the nanoparticles for the full range of Rayleigh numbers, and that the effect of the nanofluid on natural convection is much more manifest for higher values of Rayleigh number.Note de contenu :
Annexes.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/YAH7521.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11360 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité YAH/7521 YAH/7521 Thèse Bibliothèque principale Thèses Disponible
Titre : Contribution à l’étude de la convection naturelle instationnaire dans des enceintes cubiques inclinées. Type de document : texte imprimé Auteurs : Khadoudja Azzouz, Auteur ; Mahfoud Djezzar, Auteur Mention d'édition : 23/06/2019 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 89 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Physique Energétique :Photothermique convection naturelle équations de Boussinesq enceintes fermées cubiques nanofluide natural convection Boussinesq equations cubic closed enclosures nanofluid الحمل الطبيعي معادلات بوسينسك فضاء مكعب طريقة الحجوم المنتهية نانو فلويد Index. décimale : 530 Physique Résumé : In this study, we present a numerical solution of unsteady natural convection in a cubic enclosure filled with a nanofluid, inclined at an angle . The left wall at a sinusoidal temperature with time and the right wall maintained at a cold temperature Tfr and adiabatic opposite sides for a first case. In a second case of heating, we impose the opposite sides Tch and Tfr with Tch > Tfr, and both other adiabatic walls. For a third and a fourth case, periodic heating is imposed on this vertical wall. The right wall of the enclosure is maintained at a constant temperature (Tfr); however, the other walls are adiabatic.The Prandtl number is fixed at 6.2 (case of water) but the Grashof number and the volume fraction varies. Using the Boussinesq approximation. The SIMPLER algorithm was used to couple the velocity and pressure fields. We compare results from the latter with other similar results existing in the literature qualitatively or quantitatively.
Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/physique/AZZ7584.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11421 Contribution à l’étude de la convection naturelle instationnaire dans des enceintes cubiques inclinées. [texte imprimé] / Khadoudja Azzouz, Auteur ; Mahfoud Djezzar, Auteur . - 23/06/2019 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 89 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Physique Energétique :Photothermique convection naturelle équations de Boussinesq enceintes fermées cubiques nanofluide natural convection Boussinesq equations cubic closed enclosures nanofluid الحمل الطبيعي معادلات بوسينسك فضاء مكعب طريقة الحجوم المنتهية نانو فلويد Index. décimale : 530 Physique Résumé : In this study, we present a numerical solution of unsteady natural convection in a cubic enclosure filled with a nanofluid, inclined at an angle . The left wall at a sinusoidal temperature with time and the right wall maintained at a cold temperature Tfr and adiabatic opposite sides for a first case. In a second case of heating, we impose the opposite sides Tch and Tfr with Tch > Tfr, and both other adiabatic walls. For a third and a fourth case, periodic heating is imposed on this vertical wall. The right wall of the enclosure is maintained at a constant temperature (Tfr); however, the other walls are adiabatic.The Prandtl number is fixed at 6.2 (case of water) but the Grashof number and the volume fraction varies. Using the Boussinesq approximation. The SIMPLER algorithm was used to couple the velocity and pressure fields. We compare results from the latter with other similar results existing in the literature qualitatively or quantitatively.
Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/physique/AZZ7584.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11421 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité AZZ/7584 AZZ/7584 Thèse Bibliothèque principale Thèses Disponible 
Permalink
Permalink
Permalink
PermalinkPermalink
Permalink
PermalinkPermalinkPermalink
Permalink
Permalink
Permalink
Permalink
