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Auteur Abdelhadi Beghidja |
Documents disponibles écrits par cet auteur (7)
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Titre : Etude des écoulements de jets coaxiaux et leur simulation par LES/RANS. Type de document : texte imprimé Auteurs : Nabil Belkacem Safer, Auteur ; Abdelhadi Beghidja, Directeur de thèse Mention d'édition : 05/12/2019 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 118 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : G.Mécanique: Energétique simulation de grandes échelles (SGE) jet coaxial problème de Riemann Kelvin Helmholtz McCormack Large Eddy Simulation coaxial jet Riemann problem محاكاة الاضطرابات الكبرى نفاثة ثنائية المحور مشكل ريمان كيلفن هيلمهولتز ماك كورماك Index. décimale : 620 Génie Mécanique Résumé :
The work presents a numerical study of a compressible and turbulent coaxial jet,using a Large Eddy Simulation type approach. This study focuses on the implementation of a high-performance and modern numerical method to meet the requirements in terms of results accuracy and calculation cost. The code was parallelized using the Message Passing Interface (MPI) library. Inviscid fluxes are evaluated using a new linearization solver for the equations characteristic of approximate Riemann problem and the solution has been advanced over time using an explicit two-step McCormack method. The purpose of this study is to understand the initial stage of the transition process from laminar to turbulent flow in coaxial jets and study the mixing process in a compressible coaxial jet, whose primary jet is hot and whose secondary jet is unheated, through a scalar passive injected into the jet, where two cases were considered. Case 1 is a scalar passive injected into central jet and Case 2 is a scalar passive injected into the secondary jet. Particular attention is paid to the role of coherent vortices flow in the mixing process. Therefore, it has been determined that the first step in the transition process from laminar to turbulent flow in coaxial jets is initiated by the development of Kelvin Helmholtz (primary vortices) in sheer layers, while three-dimensionalization turbulence is initiated in the second step with the emergence of secondary vortices. The transverse evolution of Reynolds tensors showed that the axial Reynolds tensor contribution is associated with primary instability while the transversal Reynolds tensor contribution is associated with secondary instability. Flow self-similarity state is obtained in fully developed turbulence region. Axi-symmetric mode predominates on each shear layer in the initial flow region. Mixing process was studied using the spatial and temporal resolution of the Navier-stockes equations and the equation transport of the mixture fraction. The mean and instantaneous mixture fraction were traced and analysed. Then, using the probability density function, mixture quality was studied. Results of this study provided useful information. In particular, active mixing regions were associated with high concentrations of Root Mean Square (RMS) values. Coherent vortices play a very important role in the mixing process, and the efficiency of the mixture is maintained when the passive scalar is injected into the central jet. All results obtained are in agreement with similar experimental results of simulation jets in this study.
Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/SAF7664.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11498 Etude des écoulements de jets coaxiaux et leur simulation par LES/RANS. [texte imprimé] / Nabil Belkacem Safer, Auteur ; Abdelhadi Beghidja, Directeur de thèse . - 05/12/2019 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 118 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : G.Mécanique: Energétique simulation de grandes échelles (SGE) jet coaxial problème de Riemann Kelvin Helmholtz McCormack Large Eddy Simulation coaxial jet Riemann problem محاكاة الاضطرابات الكبرى نفاثة ثنائية المحور مشكل ريمان كيلفن هيلمهولتز ماك كورماك Index. décimale : 620 Génie Mécanique Résumé :
The work presents a numerical study of a compressible and turbulent coaxial jet,using a Large Eddy Simulation type approach. This study focuses on the implementation of a high-performance and modern numerical method to meet the requirements in terms of results accuracy and calculation cost. The code was parallelized using the Message Passing Interface (MPI) library. Inviscid fluxes are evaluated using a new linearization solver for the equations characteristic of approximate Riemann problem and the solution has been advanced over time using an explicit two-step McCormack method. The purpose of this study is to understand the initial stage of the transition process from laminar to turbulent flow in coaxial jets and study the mixing process in a compressible coaxial jet, whose primary jet is hot and whose secondary jet is unheated, through a scalar passive injected into the jet, where two cases were considered. Case 1 is a scalar passive injected into central jet and Case 2 is a scalar passive injected into the secondary jet. Particular attention is paid to the role of coherent vortices flow in the mixing process. Therefore, it has been determined that the first step in the transition process from laminar to turbulent flow in coaxial jets is initiated by the development of Kelvin Helmholtz (primary vortices) in sheer layers, while three-dimensionalization turbulence is initiated in the second step with the emergence of secondary vortices. The transverse evolution of Reynolds tensors showed that the axial Reynolds tensor contribution is associated with primary instability while the transversal Reynolds tensor contribution is associated with secondary instability. Flow self-similarity state is obtained in fully developed turbulence region. Axi-symmetric mode predominates on each shear layer in the initial flow region. Mixing process was studied using the spatial and temporal resolution of the Navier-stockes equations and the equation transport of the mixture fraction. The mean and instantaneous mixture fraction were traced and analysed. Then, using the probability density function, mixture quality was studied. Results of this study provided useful information. In particular, active mixing regions were associated with high concentrations of Root Mean Square (RMS) values. Coherent vortices play a very important role in the mixing process, and the efficiency of the mixture is maintained when the passive scalar is injected into the central jet. All results obtained are in agreement with similar experimental results of simulation jets in this study.
Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/SAF7664.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11498 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité SAF/7664 SAF/7664 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude de l' interaction choc/choc é des écoulements dans une tuyère. Type de document : texte imprimé Auteurs : Hamza Gouidmi, Auteur ; Abdelhadi Beghidja, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2015 Importance : 191 f. Format : 30 cm. Note générale : 2 copies imprimes disponibles Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : Tuyère supersonique interaction choc/ choc choc/ couche limite turbulente ou laminaire injection secondaire vectorisation fluidique supersonic nozzle, shock/shock interaction shock wave/turbulent or laminar boundary layer secondary injection, fluidic vectoring :فوھات الأسرع من الصوت، تداخل صدمة مع صدمة وصدمة مع الطبقة الحدودیة المضطربة أوالصفائحیة،
تغییراتجاه السائل بواسطة مائع، الحقن الثانويIndex. décimale : 620 Génie Mécanique Résumé : In supersonic aerodynamics, the interaction phenomena shock/shock and shock/boundary layer, impose
physical crucial problems in practical flow configurations. They are encountered in the intakes supersonic air,
nozzle Rocket engines and supersonic air inlets. In this work, several numerical calculations were made touching
directly the bottom of those interaction phenomena in the above mentioned configurations. They are based on
solving stationary Navier-Stokes equations and quasi-stationary compressible supersonic flows, laminar and
turbulent, using the FLUENT commercial. These numerical calculations were conducted for multiple
configurations at different Mach numbers and pressure and injection ratios (NPR and SPR respectively). These
parameters are directly affecting shock interaction phenomena. The results show different shock configurations
according to the parameters mentioned above. An interaction zone on a flat plate of overall large in laminar
calculation than in turbulent one and a set of shocks in the divergent nozzle with and without secondary injection
have been highlighted. These results are generally consistent with those found experimentally and numerically.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/GOU6850.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10147 Etude de l' interaction choc/choc é des écoulements dans une tuyère. [texte imprimé] / Hamza Gouidmi, Auteur ; Abdelhadi Beghidja, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2015 . - 191 f. ; 30 cm.
2 copies imprimes disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : Tuyère supersonique interaction choc/ choc choc/ couche limite turbulente ou laminaire injection secondaire vectorisation fluidique supersonic nozzle, shock/shock interaction shock wave/turbulent or laminar boundary layer secondary injection, fluidic vectoring :فوھات الأسرع من الصوت، تداخل صدمة مع صدمة وصدمة مع الطبقة الحدودیة المضطربة أوالصفائحیة،
تغییراتجاه السائل بواسطة مائع، الحقن الثانويIndex. décimale : 620 Génie Mécanique Résumé : In supersonic aerodynamics, the interaction phenomena shock/shock and shock/boundary layer, impose
physical crucial problems in practical flow configurations. They are encountered in the intakes supersonic air,
nozzle Rocket engines and supersonic air inlets. In this work, several numerical calculations were made touching
directly the bottom of those interaction phenomena in the above mentioned configurations. They are based on
solving stationary Navier-Stokes equations and quasi-stationary compressible supersonic flows, laminar and
turbulent, using the FLUENT commercial. These numerical calculations were conducted for multiple
configurations at different Mach numbers and pressure and injection ratios (NPR and SPR respectively). These
parameters are directly affecting shock interaction phenomena. The results show different shock configurations
according to the parameters mentioned above. An interaction zone on a flat plate of overall large in laminar
calculation than in turbulent one and a set of shocks in the divergent nozzle with and without secondary injection
have been highlighted. These results are generally consistent with those found experimentally and numerically.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/GOU6850.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10147 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité GOU/6850 GOU/6850 Thèse Bibliothèque principale Thèses Disponible Instabilité et interaction des macrostructures tourbillonnaires avec la couche limite dans une cavité différentiellement chauffée / Djedid Taloub
Titre : Instabilité et interaction des macrostructures tourbillonnaires avec la couche limite dans une cavité différentiellement chauffée Type de document : texte imprimé Auteurs : Djedid Taloub, Auteur ; Abdelhadi Beghidja, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2015 Importance : 117 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : Cavité fermée modèle de turbulence simulation des grandes échelles stratification thermique transfert de chaleur, RANS
closed cavity turbulence model large eddy simulation thermal stratification heat transfer تجويف مغلق نموذج التمثيل الرقمي للدوامات المضطربة الكبيرة التحول الحراري نموذج الاضطراب التوازن
الحراريIndex. décimale : 620 Génie Mécanique Résumé : In the recent years, the study of the boundary layer interaction with the flow and the influence of cavity heat transfer for strong Rayleigh numbers (2.5×109 ≤ RaH ≤ 1.4x1011) is use of various numerical simulations. The resulting velocity field can be divided into two domains: the flow of the average field in the cavity, and the fluctuating velocity field of this flow in the cavity. The cavity is the site of instabilities causing or modulating the vortex structures. In this work, a general the prospect of fluid dynamics turbulence and thermal transfer is provided based on previous experimental studies in order to develop new methods allowing the comparison between numerical simulations and experimental results in the case of turbulent
flows with unsteady macrostructures. The turbulence modeling is performed by a LES approach with a sub grid diffusivity model adapted to the natural convection. Therefore, our goal is to compare our numerical results with those obtained experimentally literature on the one hand and those established by other
numerical studies on the other hand.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/TAL6882.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10202 Instabilité et interaction des macrostructures tourbillonnaires avec la couche limite dans une cavité différentiellement chauffée [texte imprimé] / Djedid Taloub, Auteur ; Abdelhadi Beghidja, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2015 . - 117 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : Cavité fermée modèle de turbulence simulation des grandes échelles stratification thermique transfert de chaleur, RANS
closed cavity turbulence model large eddy simulation thermal stratification heat transfer تجويف مغلق نموذج التمثيل الرقمي للدوامات المضطربة الكبيرة التحول الحراري نموذج الاضطراب التوازن
الحراريIndex. décimale : 620 Génie Mécanique Résumé : In the recent years, the study of the boundary layer interaction with the flow and the influence of cavity heat transfer for strong Rayleigh numbers (2.5×109 ≤ RaH ≤ 1.4x1011) is use of various numerical simulations. The resulting velocity field can be divided into two domains: the flow of the average field in the cavity, and the fluctuating velocity field of this flow in the cavity. The cavity is the site of instabilities causing or modulating the vortex structures. In this work, a general the prospect of fluid dynamics turbulence and thermal transfer is provided based on previous experimental studies in order to develop new methods allowing the comparison between numerical simulations and experimental results in the case of turbulent
flows with unsteady macrostructures. The turbulence modeling is performed by a LES approach with a sub grid diffusivity model adapted to the natural convection. Therefore, our goal is to compare our numerical results with those obtained experimentally literature on the one hand and those established by other
numerical studies on the other hand.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/TAL6882.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10202 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité TAL/6882 TAL/6882 Thèse Bibliothèque principale Thèses Disponible
Titre : Intensification des transferts thermiques en convection forcée par l'utilisation d'une nouvelle classe de fluides porteurs dans une conduite cylindrique. Type de document : texte imprimé Auteurs : Ammar Maouassi, Auteur ; Abdelhadi Beghidja, Directeur de thèse Mention d'édition : 20/11/2019 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 210 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : G.Mécanique: Energétique Nanofluide Nanoparticule Echangeur Capteur solaire plan Al2O3 CuO SiO2 TiO2 نانوفلويد الجزيئات النانومترية مبادل حراري لوح تجميع الطاقة الشمسية المسطح Index. décimale : 620 Génie Mécanique Résumé : Numerical studies of laminar and turbulent forced convection, permanent and stationary through a cylindrical pipe for the case of a heat exchanger and the case of a flat plat solar collector, the calculations are performed for the case of water and nanofluides of metal oxides (Al2O3, CuO, SiO2, TiO2).The fluids are supposed Newtonian. The heat transfer equations governing have been resolved, by the use of finite volume method to discretize the mathematical model equations (continuity, momentum and energy equations). Dynamic and thermal fields are obtained for different values of the Reynolds number ranging from 25 to 900 and for different nanoparticles concentration of (1%, 2%, 3%, 5% and 10%).Analyses of temperature, pressure drop coefficient and the calculation Nusselt number has been realized. The results obtained show that heat transfer is better if we increased the nanoparticles concentration and the Reynolds number, and found that the best transfer fluid is the nanofluid contains nanoparticles of Al2O3followed by CuO and TiO2, and finally SiO2, and an increase of Al2O3 concentration intensifies the heat transfer coefficient without affecting the pressure drop, and another the power dissipated by the fluid transport. Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/MAO7598.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11434 Intensification des transferts thermiques en convection forcée par l'utilisation d'une nouvelle classe de fluides porteurs dans une conduite cylindrique. [texte imprimé] / Ammar Maouassi, Auteur ; Abdelhadi Beghidja, Directeur de thèse . - 20/11/2019 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 210 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : G.Mécanique: Energétique Nanofluide Nanoparticule Echangeur Capteur solaire plan Al2O3 CuO SiO2 TiO2 نانوفلويد الجزيئات النانومترية مبادل حراري لوح تجميع الطاقة الشمسية المسطح Index. décimale : 620 Génie Mécanique Résumé : Numerical studies of laminar and turbulent forced convection, permanent and stationary through a cylindrical pipe for the case of a heat exchanger and the case of a flat plat solar collector, the calculations are performed for the case of water and nanofluides of metal oxides (Al2O3, CuO, SiO2, TiO2).The fluids are supposed Newtonian. The heat transfer equations governing have been resolved, by the use of finite volume method to discretize the mathematical model equations (continuity, momentum and energy equations). Dynamic and thermal fields are obtained for different values of the Reynolds number ranging from 25 to 900 and for different nanoparticles concentration of (1%, 2%, 3%, 5% and 10%).Analyses of temperature, pressure drop coefficient and the calculation Nusselt number has been realized. The results obtained show that heat transfer is better if we increased the nanoparticles concentration and the Reynolds number, and found that the best transfer fluid is the nanofluid contains nanoparticles of Al2O3followed by CuO and TiO2, and finally SiO2, and an increase of Al2O3 concentration intensifies the heat transfer coefficient without affecting the pressure drop, and another the power dissipated by the fluid transport. Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/MAO7598.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11434 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité MAO/7598 MAO/7598 Thèse Bibliothèque principale Thèses Disponible
Titre : Intéraction des structures tourbillonnaires avec la couche limite dans une cavité différentiellement chauffée Type de document : texte imprimé Auteurs : Mohamed Chaour ; Univ. de Constantine, Éditeur scientifique ; Abdelhadi Beghidja, Directeur de thèse Année de publication : 2010 Importance : 77 f. Note générale : 01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : Volumes finis Convection naturelle Parallélépipédique Index. décimale : 620 Génie Mécanique En ligne : ../theses/gmecanique/CHA5788.pdf Permalink : index.php?lvl=notice_display&id=896 Intéraction des structures tourbillonnaires avec la couche limite dans une cavité différentiellement chauffée [texte imprimé] / Mohamed Chaour ; Univ. de Constantine, Éditeur scientifique ; Abdelhadi Beghidja, Directeur de thèse . - 2010 . - 77 f.
01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : Volumes finis Convection naturelle Parallélépipédique Index. décimale : 620 Génie Mécanique En ligne : ../theses/gmecanique/CHA5788.pdf Permalink : index.php?lvl=notice_display&id=896 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHA/5788 CHA/5788 Thèse Bibliothèque principale Thèses Disponible Permalink
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