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Titre : Analyse dynamique des structures mécaniques par la méthode des éléments finis. Type de document : texte imprimé Auteurs : Fareh Hamrit, Auteur ; Brahim Necib, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 135 f. Format : 30 cm. Note générale : copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : Structures mécaniques rigidité déformation contrainte modes de vibration éléments finis élément barre élément poutre élément plaque assemblage énergie de déformation forces internes Mechanical structures stiffness deformation stress vibration modes finite elements bar
element beam element plate element assembly deformation energy internal forces الهياكل الميكانيكية وصلابة وتشوه والإجهاد وسائط الاهتزاز والعناصر المحدودة عنصر شريط عنصر شعاع عنصر لوحة والتجمع والطاقة تشوه القوى الداخليةIndex. décimale : 620 Génie Mécanique Résumé : The mechanicaldiscrete or continuumstructures are actually of great importance in the application field of contemporary modern industry. However, during their life time these structures are often subjected to considerable external stresses or to high amplitudes of vibrations which can cause them large deformations and internal stresses which can cause them internal cracking or even their total destruction. In order to avoid these types of problems, the concept of static and dynamic analysis of these structures is recommended, and due to the complexity of their shape and size, the finite element method is the most used. The latter is currently recognized as a very powerful technique for the static and dynamic analysis of discrete or continuous structures of complicated form applied in the field of mechanics, aeronautics, civil engineering, maritime or robotics. Consequently, the calculation and
dimensioning of these mechanical systems by the finite element method plays an important role at the service of the industry for possible sizing and prediction of their lifetime. Our work consists of static and dynamic analysis of two-dimensional discrete and continuous mechanical systems using the finite element method based on the main elements of bars, beams and plates, under the effect of external excitations with different boundary conditions. The discrete structures considered are twodimensional in metallic framework interconnected to the nodes by welding, riveting or bolted under various boundary conditions. Their elements are modeled comparatively by bar elements and beam elements, while for continuous structures the elements are rectangular thin plates with different boundary conditions. The excitation forces are based on periodic, random or impulsive forces and a numerical solution by development of a program to describe the behavior of these structures is realized. The mass and stiffness matrices of all the structures are determined respectively by assembling the bars, beam and plate elements based on the kinetic and deformation energy for each element. The displacements, the node reactions and the axial forces in all the elements as well as the transverse stresses and the eigenvalues of the structures under different boundary conditions were also calculated and good results were obtained compared to those obtained using other software
Already existing. In fact, analysis using the finite element method will allow the proper dimensioning and design of complex industrial mechanical structures according to different boundary conditions, their internal loading and their vibratory level.
Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/HAM7246.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10839 Analyse dynamique des structures mécaniques par la méthode des éléments finis. [texte imprimé] / Fareh Hamrit, Auteur ; Brahim Necib, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 135 f. ; 30 cm.
copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : Structures mécaniques rigidité déformation contrainte modes de vibration éléments finis élément barre élément poutre élément plaque assemblage énergie de déformation forces internes Mechanical structures stiffness deformation stress vibration modes finite elements bar
element beam element plate element assembly deformation energy internal forces الهياكل الميكانيكية وصلابة وتشوه والإجهاد وسائط الاهتزاز والعناصر المحدودة عنصر شريط عنصر شعاع عنصر لوحة والتجمع والطاقة تشوه القوى الداخليةIndex. décimale : 620 Génie Mécanique Résumé : The mechanicaldiscrete or continuumstructures are actually of great importance in the application field of contemporary modern industry. However, during their life time these structures are often subjected to considerable external stresses or to high amplitudes of vibrations which can cause them large deformations and internal stresses which can cause them internal cracking or even their total destruction. In order to avoid these types of problems, the concept of static and dynamic analysis of these structures is recommended, and due to the complexity of their shape and size, the finite element method is the most used. The latter is currently recognized as a very powerful technique for the static and dynamic analysis of discrete or continuous structures of complicated form applied in the field of mechanics, aeronautics, civil engineering, maritime or robotics. Consequently, the calculation and
dimensioning of these mechanical systems by the finite element method plays an important role at the service of the industry for possible sizing and prediction of their lifetime. Our work consists of static and dynamic analysis of two-dimensional discrete and continuous mechanical systems using the finite element method based on the main elements of bars, beams and plates, under the effect of external excitations with different boundary conditions. The discrete structures considered are twodimensional in metallic framework interconnected to the nodes by welding, riveting or bolted under various boundary conditions. Their elements are modeled comparatively by bar elements and beam elements, while for continuous structures the elements are rectangular thin plates with different boundary conditions. The excitation forces are based on periodic, random or impulsive forces and a numerical solution by development of a program to describe the behavior of these structures is realized. The mass and stiffness matrices of all the structures are determined respectively by assembling the bars, beam and plate elements based on the kinetic and deformation energy for each element. The displacements, the node reactions and the axial forces in all the elements as well as the transverse stresses and the eigenvalues of the structures under different boundary conditions were also calculated and good results were obtained compared to those obtained using other software
Already existing. In fact, analysis using the finite element method will allow the proper dimensioning and design of complex industrial mechanical structures according to different boundary conditions, their internal loading and their vibratory level.
Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/HAM7246.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10839 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité HAM/7246 HAM/7246 Thèse Bibliothèque principale Thèses Disponible Modélisation par la méthode des éléments finis du comportement dynamique du couple roue-rail. / Latifa Boussalia
Titre : Modélisation par la méthode des éléments finis du comportement dynamique du couple roue-rail. Type de document : texte imprimé Auteurs : Latifa Boussalia, Auteur ; Ahmed Bellaouar, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 140 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : Génie Mécanique: Construction Mécanique Contact roulant contact roue-rail modélisation numérique défauts géométriques analyse modale analyse dynamique éléments finis Rolling contact wheel-rail contact numerical modeling geometrical defects modal analysis dynamic analysis finite elements الالتماس الدوراني التماس عجلة-سكة النمذجة العددية العيوب الهندسية تحليل الوسائط التحليل الديناميكي العناصر المحدودة Index. décimale : 620 Génie Mécanique Résumé :
The work presented in this thesis highlights the influence of geometrical singularities on the mechanical behavior of wheel-rail torque. With the increase in the loads transported by axles, the traffic speeds and the state of the tracks, the damage of the wheels is very solicited, leading to more or less serious accidents. The tool used is the ANSYS software based on numerical modeling using the finite element method. The objective of this thesis has been to develop a complete approach to a dynamic analysis of the wheels of the railcar and the wheel-rail pair in contact, allowing to take into account the local demands from the real geometry of the contact wheel- rail, the elastic behavior of the wheel material and the rail (steel) and the operating conditions (load on the wheel and speed). The proposed digital approach deals with two main parts. In the first part, a static analysis was carried out, aiming to model the mechanical behavior of a wheel with different forms of geometrical defects on the tread (circular shape, elliptical shape and any shape, and a perfect wheel), and the wheel-rail pair in contact. In the second part, the dynamic problem of the wheel-rail contact is solved by using the implicit temporal integration scheme. The 3D model developed takes into account only the elastic behavior of the bodies in contact, in the presence of the geometrical defect. However, the central problem in the dynamics of the couple in contact is solved by simplified methods based on the Hertz and Kalker theories implemented in the majority of finite element calculation codes. Finally, a comparative study using a simple modal analysis between the own frequencies of the wheel with and without defect has been proposed. In order to check the vibratory response of these, and to understand exactly how the vibrations may produce minor or catastrophic reactions. However, the different results were validated by an analytical calculation based on the Hertz theory and by some works in the literature.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/BOU7420.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11073 Modélisation par la méthode des éléments finis du comportement dynamique du couple roue-rail. [texte imprimé] / Latifa Boussalia, Auteur ; Ahmed Bellaouar, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 140 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : Génie Mécanique: Construction Mécanique Contact roulant contact roue-rail modélisation numérique défauts géométriques analyse modale analyse dynamique éléments finis Rolling contact wheel-rail contact numerical modeling geometrical defects modal analysis dynamic analysis finite elements الالتماس الدوراني التماس عجلة-سكة النمذجة العددية العيوب الهندسية تحليل الوسائط التحليل الديناميكي العناصر المحدودة Index. décimale : 620 Génie Mécanique Résumé :
The work presented in this thesis highlights the influence of geometrical singularities on the mechanical behavior of wheel-rail torque. With the increase in the loads transported by axles, the traffic speeds and the state of the tracks, the damage of the wheels is very solicited, leading to more or less serious accidents. The tool used is the ANSYS software based on numerical modeling using the finite element method. The objective of this thesis has been to develop a complete approach to a dynamic analysis of the wheels of the railcar and the wheel-rail pair in contact, allowing to take into account the local demands from the real geometry of the contact wheel- rail, the elastic behavior of the wheel material and the rail (steel) and the operating conditions (load on the wheel and speed). The proposed digital approach deals with two main parts. In the first part, a static analysis was carried out, aiming to model the mechanical behavior of a wheel with different forms of geometrical defects on the tread (circular shape, elliptical shape and any shape, and a perfect wheel), and the wheel-rail pair in contact. In the second part, the dynamic problem of the wheel-rail contact is solved by using the implicit temporal integration scheme. The 3D model developed takes into account only the elastic behavior of the bodies in contact, in the presence of the geometrical defect. However, the central problem in the dynamics of the couple in contact is solved by simplified methods based on the Hertz and Kalker theories implemented in the majority of finite element calculation codes. Finally, a comparative study using a simple modal analysis between the own frequencies of the wheel with and without defect has been proposed. In order to check the vibratory response of these, and to understand exactly how the vibrations may produce minor or catastrophic reactions. However, the different results were validated by an analytical calculation based on the Hertz theory and by some works in the literature.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/BOU7420.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11073 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7420 BOU/7420 Thèse Bibliothèque principale Thèses Disponible
Titre : Analyse et modélisation numerique des déformations élastiques des poutres en matériaux Piézo - Laminés Type de document : texte imprimé Auteurs : Abdelaziz Lebied, Auteur ; Brahim Necib, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 155 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : matériau intelligent PZT potentiel électrique élasticité éléments finis intelligent PZT material electric potential elasticity finite elements المادة المركبة المادة الكهربائية الضغطية الذكية الكمون الكهربائي المرونة العناصر
المحدودةIndex. décimale : 620 Génie Mécanique Résumé : Currently, intelligent systems are a rapidly developing field and booming. They have a major
advantage: their adaptability to the environment, according to changing environmental conditions.
In this context, there is a surge of publications in this field since the early 80s. Since that time,
considerable efforts in basic research has been devoted to developing new adaptive structures. The
interest of these so-called smart structures is manifested by the fact that they provide optimal
extreme problems complex responses, such as micromanipulation of micro-objects whose size
ranges from a few microns to 1 mm, objects are the micro world.
.
We were able to obtain by numerical solutions using finite element method, a precise analysis of the
different modes of deformation of the piezoelectric beams, are an important aspect related to the
polarization of PZT beams. Was used in this study to extract the digital mode that interested us, the
bending mode in the plan and highlight the one hand, the effect of polarization, and on the other
hand, the mechanical properties and on operation of the piezoelectric micro-clamp suitable to secure
the plug and removal of micro-objects of any shape. We then corroborated with any benchmarking
to compare the three studies (analytical, numerical and experimental) for validation.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/LEB7117.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10484 Analyse et modélisation numerique des déformations élastiques des poutres en matériaux Piézo - Laminés [texte imprimé] / Abdelaziz Lebied, Auteur ; Brahim Necib, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2017 . - 155 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : matériau intelligent PZT potentiel électrique élasticité éléments finis intelligent PZT material electric potential elasticity finite elements المادة المركبة المادة الكهربائية الضغطية الذكية الكمون الكهربائي المرونة العناصر
المحدودةIndex. décimale : 620 Génie Mécanique Résumé : Currently, intelligent systems are a rapidly developing field and booming. They have a major
advantage: their adaptability to the environment, according to changing environmental conditions.
In this context, there is a surge of publications in this field since the early 80s. Since that time,
considerable efforts in basic research has been devoted to developing new adaptive structures. The
interest of these so-called smart structures is manifested by the fact that they provide optimal
extreme problems complex responses, such as micromanipulation of micro-objects whose size
ranges from a few microns to 1 mm, objects are the micro world.
.
We were able to obtain by numerical solutions using finite element method, a precise analysis of the
different modes of deformation of the piezoelectric beams, are an important aspect related to the
polarization of PZT beams. Was used in this study to extract the digital mode that interested us, the
bending mode in the plan and highlight the one hand, the effect of polarization, and on the other
hand, the mechanical properties and on operation of the piezoelectric micro-clamp suitable to secure
the plug and removal of micro-objects of any shape. We then corroborated with any benchmarking
to compare the three studies (analytical, numerical and experimental) for validation.Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/LEB7117.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10484 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité LEB/7117 LEB/7117 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude et modélisation du comportement de structures osseuses sous sollicitations complexes. Type de document : texte imprimé Auteurs : Dalila Belaid, Auteur ; Ali Bouchoucha, Directeur de thèse ; A. Germaneau, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 193 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : Biomécanique Fracture de fémur Stabilisation du tibia Eléments finis Biomechanics Femur fracture Stabilization of the tibia Finite elements الميكانيكا الحيوية كسر عظم الفخذ استقرار الساق العناصر المحددة Index. décimale : 620 Génie Mécanique Résumé : In order to analyze the biomechanical behavior of bone structures, such as femur and tibia, for biomedical or traumatic applications, finite element models are increasingly used throughout the range of orthopedic devices. It is adapted to the study of the behavior of any physiological unit, despite its complexity. Numerical simulation combined with techniques of acquisition of the geometry of the bone structure made it possible to build personalized models CT-based. Subject specific finite element models are typically used to predict the biomechanical response of human bones
This biomechanical work combined the finite element method and CT scan to study, first, the stability of the tibial plateau fractured and repaired by a minimally invasive method. This technique uses a balloon and cement augmentation. As for the second, is to study the fracture risk of the femur under the effect of alignment of the limb.
The results of the simulation of the tibial plateau have shown that cement plays a very important role. Indeed, it allows the reduction of the depression, the distribution of the stresses in the tibial plateau and facilitates the transfer of the load. However, femur simulation results have shown the influence of angular anomalies on the distribution of stresses. Valgus deformity increases the risk of cervical fracture. On the other hand, the modification of the distribution of the stress as a function of the alignment of the load affects the atypical fracture of the femur.
These results underscored the potential of custom finite element modeling. This modeling made it possible to analyze the stabilization of the tibial plateau by a new technique tibioplasty. In addition, an evaluation of the fracture risk indicators influenced by the angular anomaly of the lower limb in the frontal plane was performed
Note de contenu : Annexes.
Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/BEL7480.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11312 Etude et modélisation du comportement de structures osseuses sous sollicitations complexes. [texte imprimé] / Dalila Belaid, Auteur ; Ali Bouchoucha, Directeur de thèse ; A. Germaneau, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 193 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : Biomécanique Fracture de fémur Stabilisation du tibia Eléments finis Biomechanics Femur fracture Stabilization of the tibia Finite elements الميكانيكا الحيوية كسر عظم الفخذ استقرار الساق العناصر المحددة Index. décimale : 620 Génie Mécanique Résumé : In order to analyze the biomechanical behavior of bone structures, such as femur and tibia, for biomedical or traumatic applications, finite element models are increasingly used throughout the range of orthopedic devices. It is adapted to the study of the behavior of any physiological unit, despite its complexity. Numerical simulation combined with techniques of acquisition of the geometry of the bone structure made it possible to build personalized models CT-based. Subject specific finite element models are typically used to predict the biomechanical response of human bones
This biomechanical work combined the finite element method and CT scan to study, first, the stability of the tibial plateau fractured and repaired by a minimally invasive method. This technique uses a balloon and cement augmentation. As for the second, is to study the fracture risk of the femur under the effect of alignment of the limb.
The results of the simulation of the tibial plateau have shown that cement plays a very important role. Indeed, it allows the reduction of the depression, the distribution of the stresses in the tibial plateau and facilitates the transfer of the load. However, femur simulation results have shown the influence of angular anomalies on the distribution of stresses. Valgus deformity increases the risk of cervical fracture. On the other hand, the modification of the distribution of the stress as a function of the alignment of the load affects the atypical fracture of the femur.
These results underscored the potential of custom finite element modeling. This modeling made it possible to analyze the stabilization of the tibial plateau by a new technique tibioplasty. In addition, an evaluation of the fracture risk indicators influenced by the angular anomaly of the lower limb in the frontal plane was performed
Note de contenu : Annexes.
Diplôme : Doctorat en sciences En ligne : ../theses/gmecanique/BEL7480.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11312 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEL/7480 BEL/7480 Thèse Bibliothèque principale Thèses Disponible
Titre : Stabilized numerical schemes for iterative solution of the generalized Stokes problem. Type de document : texte imprimé Auteurs : Alima Chibani, Auteur ; Nasserdine Kechkar, Directeur de thèse Mention d'édition : 30/11/2020 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2020 Importance : 85 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
MathématiquesTags : Mathematiques: Analyse numérique Stokes problem Finite elements Stabilization Iterative methods Problème de Stokes Eléments finis Stabilisation Méthodes itératives مشكل ستوكس العناصر المنتهية الاستقرار الطرق التكرارية Index. décimale : 510 Mathématiques Résumé :
In this thesis, some novel discrete formulations for stabilizing the mixed nite element method Q1-Q0 (bilinear velocity and constant pressure approximations) are introduced and discussed for the generalized Stokes problem. These are based on stabilizing discontinuous pressure approximations via local jump operators. The developing idea consists in a reduction of terms in the local jump formulation, introduced earlier, in such a way that stability and convergence properties are preserved. Moreover, some iterative methods of conjugate gradient type are discussed and their algorithms are presented. These are used for the iterative solution of the algebraic systems of linear equations which arise from the spatial discretization of the continuous problem. The computer implementation aspects and numerical evaluation of the stabilized discrete formulations are also considered. For illustrating the numerical performance of the proposed approaches and comparing the three versions of the local jump methods against the global jump setting, some obtained results for two test generalized Stokes problems are presented. Numerical tests con rm the stability and accuracy characteristics of the resulting approximations. Likewise, the numerical reliability of the discussed iterative solvers is assessed.Diplôme : Doctorat en sciences En ligne : ../theses/math/CHI7709.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11543 Stabilized numerical schemes for iterative solution of the generalized Stokes problem. [texte imprimé] / Alima Chibani, Auteur ; Nasserdine Kechkar, Directeur de thèse . - 30/11/2020 . - جامعة الإخوة منتوري قسنطينة, 2020 . - 85 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
MathématiquesTags : Mathematiques: Analyse numérique Stokes problem Finite elements Stabilization Iterative methods Problème de Stokes Eléments finis Stabilisation Méthodes itératives مشكل ستوكس العناصر المنتهية الاستقرار الطرق التكرارية Index. décimale : 510 Mathématiques Résumé :
In this thesis, some novel discrete formulations for stabilizing the mixed nite element method Q1-Q0 (bilinear velocity and constant pressure approximations) are introduced and discussed for the generalized Stokes problem. These are based on stabilizing discontinuous pressure approximations via local jump operators. The developing idea consists in a reduction of terms in the local jump formulation, introduced earlier, in such a way that stability and convergence properties are preserved. Moreover, some iterative methods of conjugate gradient type are discussed and their algorithms are presented. These are used for the iterative solution of the algebraic systems of linear equations which arise from the spatial discretization of the continuous problem. The computer implementation aspects and numerical evaluation of the stabilized discrete formulations are also considered. For illustrating the numerical performance of the proposed approaches and comparing the three versions of the local jump methods against the global jump setting, some obtained results for two test generalized Stokes problems are presented. Numerical tests con rm the stability and accuracy characteristics of the resulting approximations. Likewise, the numerical reliability of the discussed iterative solvers is assessed.Diplôme : Doctorat en sciences En ligne : ../theses/math/CHI7709.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11543 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHI/7709 CHI/7709 Thèse Bibliothèque principale Thèses Disponible
