Philippe Rogeon - Academia.edu (original) (raw)
Papers by Philippe Rogeon
Applied Mathematical Modelling, 2014
ABSTRACT This paper investigates the essential conditions to improve the accuracy of a resistance... more ABSTRACT This paper investigates the essential conditions to improve the accuracy of a resistance spot welding computational study of advanced zinc coated steel sheets using rounded tip electrode. An experimental analysis is performed to highlight the required considerations for a suitable simulation. A sequential Electrical-Thermal-Metallurgical and Mechanical (ETMM) finite element analysis with appropriate precautions of the contact conditions enables to accurately simulate the nugget development during the welding. A critical smooth evolution of the contact radius is required. A fine meshing with an interfacial mesh size of at least 0.05 10-3m combined with a coupling time step of 0.0025s between the electrical-thermal-metallurgical and the mechanical analysis allows a regular incrementation of the contact radius, without burdening the time computing. Accurate values of the contact resistance depending on the interfacial pressure and temperature are essential for a good simulation of the nugget size. The ETMM calculation is successfully extended to the simulation of the welding of a typical two sheets assembly.
Heating in spark plasma sintering is a key point of this manufacturing process that requires adva... more Heating in spark plasma sintering is a key point of this manufacturing process that requires advanced simulation to predict the thermal gradients present during the process and adjust them. Electric and thermal contact resistances have a prominent role in these gradients. Their determination is difficult as they vary with pressure and temperature. A calibration method is used to determine all of the contact resistances present within tools of different sizes. Ex situ measurements were also performed to validate the results of the in-situ calibrations. An extended predictive and scalable contacts model was developed and reveals the great importance and diversity of the contact resistances responsible for the general heating of the column and high thermal gradients between the parts. The ex/in situ comparison highlights a high lateral thermal contact resistance and the presence of a possible phenomenon of electric current facilitation across the lateral interface for the high temperatures.
Numerical Heat Transfer, Part B: Fundamentals, 2006
ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which char... more ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which characterize the thermal behavior of two solids in combined thermal and electrical contact, i.e., the heat flux released at the interface, the partition coefficient of this heat flux, and the thermal contact conductance between the two solids. The parameter estimation problem is performed with the Levenberg-Marquardt method. A detailed analysis of the linear dependency of the contact parameters needed to design a robust estimation tool is presented. Despite a weak correlation between the partition coefficient and thermal conductance, the results show that the estimation is feasible and the method developed is an effective tool for a complete thermal characterization of the contact interface. The article concludes with an elementary Monte Carlo study to validate the developed method for estimating the confidence intervals.
Volume 4: Fluid Structure Interaction, Parts A and B, 2006
The aim of this study is to estimate residual stresses and distortions during the assembly of dis... more The aim of this study is to estimate residual stresses and distortions during the assembly of dissimilar metallic materials welded by Electron Beam Welding (EBW) technique. This work is motivated by a new welding procedure for the manufacture of large speed reduction gear. The gear consists of a central hub of S275J2G3 steel and a toothed wheel of 32CrMoV13 steel, chosen for its high fatigue performances. Preliminary experimental welding tests have shown the opening of the joint plane during the circular welding of the gear leading to lack-of-fusion defects. To improve the joining technique, a thermomechanical model has been developed to predict the opening of the joint plane during welding. A two-dimensional finite element model has been applied on a simplified geometry of smaller size. The opening of the joint plane has been modelled by two different ways, the first one uses activation / deactivation elements and the second one uses specific contact elements. Both techniques have shown similar displacements. The assumptions of plane stress or generalized plane strain are discussed. Numerical results obtained with similar metals with or without metallurgical transformations are presented. Calculations carried out with dissimilar metals are compared with experiments in terms of fusion zone size and displacements.
ABSTRACT Estimation d'un terme source et de l'interface solide liquide dans un pr... more ABSTRACT Estimation d'un terme source et de l'interface solide liquide dans un problème bidimensionnel ; Application au soudage par faisceau d'électrons. Résumé – Cet article présente une méthodologie pour l'estimation de l'énergie de soudage lors d'une opération de soudage par faisceau d'électrons. L'objectif est d'identifier dans un plan transverse à l'axe de soudage et à chaque pas de temps la distribution énergétique dans les zones vaporisée et fondue. La méthode utilisée est la méthode de régularisation itérative. Le modèle développé est un modèle thermo-métallurgique ne tenant pas compte des phénomènes convectifs dans les zones vaporisée et fondue. Nomenclature a diffusivité thermique (m².s-1) b constante pour la réaction martensitique Ci chaleur spécifique de la phase i D n vecteur de la direction de descente f(z) répartition de l'énergie 2 x t a Fo ∆ = ∆ delta Fourier h profondeur de pénétration (m) Hγ, Hα enthalpies des phases γ et α (J.m-3) ∆H fus enthalpie de fusion (J.Kg-1) ∆H vap enthalpie de vaporisation (J.Kg-1) J(S) fonction résiduelle n J ∇ gradient de la fonctionnelle Lij, γα L énergie de transformation (J.m-3) Ms température de début de transformation martensitique n, n* nombre d'itérations, dernière itération Pi,P, P eq proportion de phase métallurgique z, x, y coordonnées spatiales (m) S(z,x,t),S n+1 terme source (W.m-3) T inf , T 0 températures externe et initiale (°C). T température de l'échantillon (°C) U, I b tension et intensité de soudage. v vitesse de soudage (m.s-1) Y température expérimentale (°C) η rendement de soudage γ n paramètre de descente δ² critère de convergence ε(Τ) emissivité de l'échantillon ε 1 critère d'arrêt λi conductivité de la phase i (W.m-1.K-1) ρi masse volumique de la phase i (Kg.m-3) σ² écart type Ψ(z,r,t) variable adjointe Φ diamètre du faisceau τ fonction de retard
Revue européenne des éléments finis, 2004
Mecanique et Industries, 2006
ABSTRACT Cet article présente un modèle de connaissance pour mieux comprendre et expliquer les mé... more ABSTRACT Cet article présente un modèle de connaissance pour mieux comprendre et expliquer les mécanismes à l’origine de la formation de la soudure dans le procédé de soudage par point en nous limitant ici au cas d’assemblages symétriques de tôles nues en acier extra-doux. Dans une première approche, on considère un modèle simplifié prenant en compte les couplages entre les phénomènes électrique, thermique et métallurgique dans l’assemblage mais en supposant les surfaces de contact constantes aux interfaces électrode-tôle et tôle-tôle. Dans une seconde approche le modèle est complété par un calcul mécanique qui permet de calculer les évolutions des surfaces de contact. Les résistances de contact électrique et thermique sont mesurées en fonction de la température et de la pression sur un dispositif expérimental conçu à cet effet. La variation des profils des électrodes en fonction du nombre de soudures réalisées et ses conséquences sur les surfaces de contact sont de même présentées. Le modèle numérique est validé en comparant, d’une part, la taille et la forme des points soudés relevées expérimentalement et calculées numériquement et, d’autre part, les cinétiques thermiques mesurées et calculées dans les électrodes et les tôles. Les techniques d’instrumentation mises au point visent à limiter les perturbations inévitables générées par l’intrusion des capteurs. Les hypothèses et les jeux de données considérés dans le modèle pour définir les conditions interfaciales sont enfin discutés.
Matériaux & Techniques, 2011
... P. Carre, P. Rogeon, T. Loulou, G. Sierra, Caractérisations thermique, élec-trique et interfa... more ... P. Carre, P. Rogeon, T. Loulou, G. Sierra, Caractérisations thermique, élec-trique et interfaciale en vue d'une étude nu-mérique d'un procédé d'assemblage de ma-tériaux de contact. Proceeding of the 14ème Journée Internationale de Thermique, Djerba, Tunisie 2729 Mars ...
Solid State Phenomena, 2011
... Denis Carron 1,a , Elise Gauthier 1,b , Cédric Pouvreau 1,c , Philippe Rogeon 1,d , ... Centr... more ... Denis Carron 1,a , Elise Gauthier 1,b , Cédric Pouvreau 1,c , Philippe Rogeon 1,d , ... Centre de Recherche Ch. Huygens, BP 92116, 56321 Lorient Cedex, France 2PSA Peugeot-Citroën, DITV/PMXP/CEB/ASG, Centre Technique de Vélizy, Route de Gisy, ...
Numerical Heat Transfer, Part B: Fundamentals, 2006
ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which char... more ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which characterize the thermal behavior of two solids in combined thermal and electrical contact, i.e., the heat flux released at the interface, the partition coefficient of this heat flux, and the thermal contact conductance between the two solids. The parameter estimation problem is performed with the Levenberg-Marquardt method. A detailed analysis of the linear dependency of the contact parameters needed to design a robust estimation tool is presented. Despite a weak correlation between the partition coefficient and thermal conductance, the results show that the estimation is feasible and the method developed is an effective tool for a complete thermal characterization of the contact interface. The article concludes with an elementary Monte Carlo study to validate the developed method for estimating the confidence intervals.
Numerical Heat Transfer, Part A: Applications, 2006
... the evolution of the mechanical contact influence the weld growth mechanisms of spot welds [1... more ... the evolution of the mechanical contact influence the weld growth mechanisms of spot welds [11. Z. Feng , SS Babu , ML Santella ... obtained according to a mechanical analysis which is followed by an electrothermometallurgical analysis and vice versa [77. V. Robin, A. Sanchez ...
Journal of Materials Processing Technology, 2012
ABSTRACT This paper investigates the influence of coating on the nugget development during resist... more ABSTRACT This paper investigates the influence of coating on the nugget development during resistance spot welding of Zn coated steel sheets using rounded tip electrodes. The study relies on an experimental observation of zinc behaviour coupled with a numerical Electro-Thermo-Metallurgical–Mechanical analysis. The electro-thermal contact surface enlargement due to zinc ejection at sheet/sheet and electrode/sheet interfaces is found to have a negligible effect on the nugget development. The numerical analysis shows that the dispersion on the efficient weld size, attributable to the zinc effect, is below 10%.
Journal of Materials Engineering and Performance, 2014
ABSTRACT Resistance spot welding is a technique widely used by the automotive industry to assembl... more ABSTRACT Resistance spot welding is a technique widely used by the automotive industry to assemble thin steel sheets. The cyclic thermo-mechanical loading associated with the accumulation of weld spots progressively deteriorates the electrodes. This study addresses the development of a comprehensive multi-physical model that describes the sequential deterioration. Welding tests achieved on uncoated and Zn-coated steel sheets are analyzed. Finite element analysis is performed using an electrical-thermal-metallurgical model. A numerical experimental design is carried out to highlight the main process parameters and boundary conditions which affect electrode degradation.
International Journal of Thermal Sciences, 2011
... Permissions & Reprints. Numerical computation of thermal and electrical constriction resi... more ... Permissions & Reprints. Numerical computation of thermal and electrical constriction resistance in finite tube. K. Tahar Chaouch a , b , T. Loulou a , Corresponding Author Contact Information , E-mail The Corresponding Author , Ph. Rogeon b and Y. Benkhedda b. ...
International Journal of Thermal Sciences, 2002
... small star, filled This article is a follow up a communication presented by the authors at th... more ... small star, filled This article is a follow up a communication presented by the authors at the EUROTHERM Seminar 68, Inverse problems and experimental design in thermal and mechanical engineering, held in Poitiers in March 2001. ...
Ce travail se situe en amont de l’étude de l’assemblage par soudage résistif d’un matériau de con... more Ce travail se situe en amont de l’étude de l’assemblage par soudage résistif d’un matériau de contact sur son support en cuivre. On y présente d’une part la caractérisation des propriétés thermique et électrique d’un matériau composite (AgSnO2) doté d’une matrice conductrice (Ag) et de renforts (SnO2) et d’autre part la détermination des résistances de contact électrique et thermique du couple de matériaux concerné lors du processus d’assemblage. La singularité de ce travail réside dans la mise au point d’une métrologie adaptée aux propriétés extrêmes de la matrice (forte conductivité électrique et thermique) et à la méthode d’élaboration de ce matériau (pastillage et frittage).
Applied Thermal Engineering, 2011
In this paper, the problem of transient heat transfer in sliding contact is studied analytically ... more In this paper, the problem of transient heat transfer in sliding contact is studied analytically and numerically.
Applied Mathematical Modelling, 2014
ABSTRACT This paper investigates the essential conditions to improve the accuracy of a resistance... more ABSTRACT This paper investigates the essential conditions to improve the accuracy of a resistance spot welding computational study of advanced zinc coated steel sheets using rounded tip electrode. An experimental analysis is performed to highlight the required considerations for a suitable simulation. A sequential Electrical-Thermal-Metallurgical and Mechanical (ETMM) finite element analysis with appropriate precautions of the contact conditions enables to accurately simulate the nugget development during the welding. A critical smooth evolution of the contact radius is required. A fine meshing with an interfacial mesh size of at least 0.05 10-3m combined with a coupling time step of 0.0025s between the electrical-thermal-metallurgical and the mechanical analysis allows a regular incrementation of the contact radius, without burdening the time computing. Accurate values of the contact resistance depending on the interfacial pressure and temperature are essential for a good simulation of the nugget size. The ETMM calculation is successfully extended to the simulation of the welding of a typical two sheets assembly.
Heating in spark plasma sintering is a key point of this manufacturing process that requires adva... more Heating in spark plasma sintering is a key point of this manufacturing process that requires advanced simulation to predict the thermal gradients present during the process and adjust them. Electric and thermal contact resistances have a prominent role in these gradients. Their determination is difficult as they vary with pressure and temperature. A calibration method is used to determine all of the contact resistances present within tools of different sizes. Ex situ measurements were also performed to validate the results of the in-situ calibrations. An extended predictive and scalable contacts model was developed and reveals the great importance and diversity of the contact resistances responsible for the general heating of the column and high thermal gradients between the parts. The ex/in situ comparison highlights a high lateral thermal contact resistance and the presence of a possible phenomenon of electric current facilitation across the lateral interface for the high temperatures.
Numerical Heat Transfer, Part B: Fundamentals, 2006
ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which char... more ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which characterize the thermal behavior of two solids in combined thermal and electrical contact, i.e., the heat flux released at the interface, the partition coefficient of this heat flux, and the thermal contact conductance between the two solids. The parameter estimation problem is performed with the Levenberg-Marquardt method. A detailed analysis of the linear dependency of the contact parameters needed to design a robust estimation tool is presented. Despite a weak correlation between the partition coefficient and thermal conductance, the results show that the estimation is feasible and the method developed is an effective tool for a complete thermal characterization of the contact interface. The article concludes with an elementary Monte Carlo study to validate the developed method for estimating the confidence intervals.
Volume 4: Fluid Structure Interaction, Parts A and B, 2006
The aim of this study is to estimate residual stresses and distortions during the assembly of dis... more The aim of this study is to estimate residual stresses and distortions during the assembly of dissimilar metallic materials welded by Electron Beam Welding (EBW) technique. This work is motivated by a new welding procedure for the manufacture of large speed reduction gear. The gear consists of a central hub of S275J2G3 steel and a toothed wheel of 32CrMoV13 steel, chosen for its high fatigue performances. Preliminary experimental welding tests have shown the opening of the joint plane during the circular welding of the gear leading to lack-of-fusion defects. To improve the joining technique, a thermomechanical model has been developed to predict the opening of the joint plane during welding. A two-dimensional finite element model has been applied on a simplified geometry of smaller size. The opening of the joint plane has been modelled by two different ways, the first one uses activation / deactivation elements and the second one uses specific contact elements. Both techniques have shown similar displacements. The assumptions of plane stress or generalized plane strain are discussed. Numerical results obtained with similar metals with or without metallurgical transformations are presented. Calculations carried out with dissimilar metals are compared with experiments in terms of fusion zone size and displacements.
ABSTRACT Estimation d'un terme source et de l'interface solide liquide dans un pr... more ABSTRACT Estimation d'un terme source et de l'interface solide liquide dans un problème bidimensionnel ; Application au soudage par faisceau d'électrons. Résumé – Cet article présente une méthodologie pour l'estimation de l'énergie de soudage lors d'une opération de soudage par faisceau d'électrons. L'objectif est d'identifier dans un plan transverse à l'axe de soudage et à chaque pas de temps la distribution énergétique dans les zones vaporisée et fondue. La méthode utilisée est la méthode de régularisation itérative. Le modèle développé est un modèle thermo-métallurgique ne tenant pas compte des phénomènes convectifs dans les zones vaporisée et fondue. Nomenclature a diffusivité thermique (m².s-1) b constante pour la réaction martensitique Ci chaleur spécifique de la phase i D n vecteur de la direction de descente f(z) répartition de l'énergie 2 x t a Fo ∆ = ∆ delta Fourier h profondeur de pénétration (m) Hγ, Hα enthalpies des phases γ et α (J.m-3) ∆H fus enthalpie de fusion (J.Kg-1) ∆H vap enthalpie de vaporisation (J.Kg-1) J(S) fonction résiduelle n J ∇ gradient de la fonctionnelle Lij, γα L énergie de transformation (J.m-3) Ms température de début de transformation martensitique n, n* nombre d'itérations, dernière itération Pi,P, P eq proportion de phase métallurgique z, x, y coordonnées spatiales (m) S(z,x,t),S n+1 terme source (W.m-3) T inf , T 0 températures externe et initiale (°C). T température de l'échantillon (°C) U, I b tension et intensité de soudage. v vitesse de soudage (m.s-1) Y température expérimentale (°C) η rendement de soudage γ n paramètre de descente δ² critère de convergence ε(Τ) emissivité de l'échantillon ε 1 critère d'arrêt λi conductivité de la phase i (W.m-1.K-1) ρi masse volumique de la phase i (Kg.m-3) σ² écart type Ψ(z,r,t) variable adjointe Φ diamètre du faisceau τ fonction de retard
Revue européenne des éléments finis, 2004
Mecanique et Industries, 2006
ABSTRACT Cet article présente un modèle de connaissance pour mieux comprendre et expliquer les mé... more ABSTRACT Cet article présente un modèle de connaissance pour mieux comprendre et expliquer les mécanismes à l’origine de la formation de la soudure dans le procédé de soudage par point en nous limitant ici au cas d’assemblages symétriques de tôles nues en acier extra-doux. Dans une première approche, on considère un modèle simplifié prenant en compte les couplages entre les phénomènes électrique, thermique et métallurgique dans l’assemblage mais en supposant les surfaces de contact constantes aux interfaces électrode-tôle et tôle-tôle. Dans une seconde approche le modèle est complété par un calcul mécanique qui permet de calculer les évolutions des surfaces de contact. Les résistances de contact électrique et thermique sont mesurées en fonction de la température et de la pression sur un dispositif expérimental conçu à cet effet. La variation des profils des électrodes en fonction du nombre de soudures réalisées et ses conséquences sur les surfaces de contact sont de même présentées. Le modèle numérique est validé en comparant, d’une part, la taille et la forme des points soudés relevées expérimentalement et calculées numériquement et, d’autre part, les cinétiques thermiques mesurées et calculées dans les électrodes et les tôles. Les techniques d’instrumentation mises au point visent à limiter les perturbations inévitables générées par l’intrusion des capteurs. Les hypothèses et les jeux de données considérés dans le modèle pour définir les conditions interfaciales sont enfin discutés.
Matériaux & Techniques, 2011
... P. Carre, P. Rogeon, T. Loulou, G. Sierra, Caractérisations thermique, élec-trique et interfa... more ... P. Carre, P. Rogeon, T. Loulou, G. Sierra, Caractérisations thermique, élec-trique et interfaciale en vue d'une étude nu-mérique d'un procédé d'assemblage de ma-tériaux de contact. Proceeding of the 14ème Journée Internationale de Thermique, Djerba, Tunisie 2729 Mars ...
Solid State Phenomena, 2011
... Denis Carron 1,a , Elise Gauthier 1,b , Cédric Pouvreau 1,c , Philippe Rogeon 1,d , ... Centr... more ... Denis Carron 1,a , Elise Gauthier 1,b , Cédric Pouvreau 1,c , Philippe Rogeon 1,d , ... Centre de Recherche Ch. Huygens, BP 92116, 56321 Lorient Cedex, France 2PSA Peugeot-Citroën, DITV/PMXP/CEB/ASG, Centre Technique de Vélizy, Route de Gisy, ...
Numerical Heat Transfer, Part B: Fundamentals, 2006
ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which char... more ABSTRACT This work consists of estimating simultaneously the thermophysical parameters which characterize the thermal behavior of two solids in combined thermal and electrical contact, i.e., the heat flux released at the interface, the partition coefficient of this heat flux, and the thermal contact conductance between the two solids. The parameter estimation problem is performed with the Levenberg-Marquardt method. A detailed analysis of the linear dependency of the contact parameters needed to design a robust estimation tool is presented. Despite a weak correlation between the partition coefficient and thermal conductance, the results show that the estimation is feasible and the method developed is an effective tool for a complete thermal characterization of the contact interface. The article concludes with an elementary Monte Carlo study to validate the developed method for estimating the confidence intervals.
Numerical Heat Transfer, Part A: Applications, 2006
... the evolution of the mechanical contact influence the weld growth mechanisms of spot welds [1... more ... the evolution of the mechanical contact influence the weld growth mechanisms of spot welds [11. Z. Feng , SS Babu , ML Santella ... obtained according to a mechanical analysis which is followed by an electrothermometallurgical analysis and vice versa [77. V. Robin, A. Sanchez ...
Journal of Materials Processing Technology, 2012
ABSTRACT This paper investigates the influence of coating on the nugget development during resist... more ABSTRACT This paper investigates the influence of coating on the nugget development during resistance spot welding of Zn coated steel sheets using rounded tip electrodes. The study relies on an experimental observation of zinc behaviour coupled with a numerical Electro-Thermo-Metallurgical–Mechanical analysis. The electro-thermal contact surface enlargement due to zinc ejection at sheet/sheet and electrode/sheet interfaces is found to have a negligible effect on the nugget development. The numerical analysis shows that the dispersion on the efficient weld size, attributable to the zinc effect, is below 10%.
Journal of Materials Engineering and Performance, 2014
ABSTRACT Resistance spot welding is a technique widely used by the automotive industry to assembl... more ABSTRACT Resistance spot welding is a technique widely used by the automotive industry to assemble thin steel sheets. The cyclic thermo-mechanical loading associated with the accumulation of weld spots progressively deteriorates the electrodes. This study addresses the development of a comprehensive multi-physical model that describes the sequential deterioration. Welding tests achieved on uncoated and Zn-coated steel sheets are analyzed. Finite element analysis is performed using an electrical-thermal-metallurgical model. A numerical experimental design is carried out to highlight the main process parameters and boundary conditions which affect electrode degradation.
International Journal of Thermal Sciences, 2011
... Permissions & Reprints. Numerical computation of thermal and electrical constriction resi... more ... Permissions & Reprints. Numerical computation of thermal and electrical constriction resistance in finite tube. K. Tahar Chaouch a , b , T. Loulou a , Corresponding Author Contact Information , E-mail The Corresponding Author , Ph. Rogeon b and Y. Benkhedda b. ...
International Journal of Thermal Sciences, 2002
... small star, filled This article is a follow up a communication presented by the authors at th... more ... small star, filled This article is a follow up a communication presented by the authors at the EUROTHERM Seminar 68, Inverse problems and experimental design in thermal and mechanical engineering, held in Poitiers in March 2001. ...
Ce travail se situe en amont de l’étude de l’assemblage par soudage résistif d’un matériau de con... more Ce travail se situe en amont de l’étude de l’assemblage par soudage résistif d’un matériau de contact sur son support en cuivre. On y présente d’une part la caractérisation des propriétés thermique et électrique d’un matériau composite (AgSnO2) doté d’une matrice conductrice (Ag) et de renforts (SnO2) et d’autre part la détermination des résistances de contact électrique et thermique du couple de matériaux concerné lors du processus d’assemblage. La singularité de ce travail réside dans la mise au point d’une métrologie adaptée aux propriétés extrêmes de la matrice (forte conductivité électrique et thermique) et à la méthode d’élaboration de ce matériau (pastillage et frittage).
Applied Thermal Engineering, 2011
In this paper, the problem of transient heat transfer in sliding contact is studied analytically ... more In this paper, the problem of transient heat transfer in sliding contact is studied analytically and numerically.