Extension of level set model to the numerical modeling of multifront delamination problems for composite laminates

International audienceFor numerical simulation of delamination, the approach used by the industry usually consists in using interface elements such as cohesive ones. This can be time consuming or lead to mesh size problems and currently limits the dimension of parts that can be optimized in pre-design stage of industrial projects.To avoid that, an interesting approach was proposed by F.P. van der Meer et al. [1] . First ,they use an implicit description of the delamination front that does not depend on the mesh (based on a level-set field). And second they assume that the cohesive zone reduces to a line and use anexplicit energy-based criterion from fracture mechanics to drive crack growth. This model showed good results in agreement with cohesive zone ones for the 2D case of a 2-ply carbon-epoxy membrane submitted to tension with a unique delamination front[1].We will show that it can be extended to the case of multifront delamination problems (see e.g. in Figure1). Comparisons to numerical simulations with cohesive elements will be done

Extension of level set model to the numerical modeling of multifront delamination problems for composite laminates

International audienceFor numerical simulation of delamination, the approach used by the industry usually consists in using interface elements such as cohesive ones. This can be time consuming or lead to mesh size problems and currently limits the dimension of parts that can be optimized in pre-design stage of industrial projects.To avoid that, an interesting approach was proposed by F.P. van der Meer et al. [1] . First ,they use an implicit description of the delamination front that does not depend on the mesh (based on a level-set field). And second they assume that the cohesive zone reduces to a line and use anexplicit energy-based criterion from fracture mechanics to drive crack growth. This model showed good results in agreement with cohesive zone ones for the 2D case of a 2-ply carbon-epoxy membrane submitted to tension with a unique delamination front[1].We will show that it can be extended to the case of multifront delamination problems (see e.g. in Figure1). Comparisons to numerical simulations with cohesive elements will be done

Extension of level set model to the numerical modeling of multifront delamination problems for composite laminates

International audienceFor numerical simulation of delamination, the approach used by the industry usually consists in using interface elements such as cohesive ones. This can be time consuming or lead to mesh size problems and currently limits the dimension of parts that can be optimized in pre-design stage of industrial projects.To avoid that, an interesting approach was proposed by F.P. van der Meer et al. [1] . First ,they use an implicit description of the delamination front that does not depend on the mesh (based on a level-set field). And second they assume that the cohesive zone reduces to a line and use anexplicit energy-based criterion from fracture mechanics to drive crack growth. This model showed good results in agreement with cohesive zone ones for the 2D case of a 2-ply carbon-epoxy membrane submitted to tension with a unique delamination front[1].We will show that it can be extended to the case of multifront delamination problems (see e.g. in Figure1). Comparisons to numerical simulations with cohesive elements will be done

Bridging the Gap between the User's Digital and Physical Worlds with Compelling Real Life Social Applications

Nowadays, the majority of web sites and web-based applications encourage their users to engage in social interactions such as adding comments, expressing opinions or sharing content with their friends in social networking websites. Social activities involve basically: (i) users, (ii) user generated content -UGCthat users create and share and (iii) resources that are described with the created content. The logical structure of the underlying knowledge emerges as a set of links between the three aforementioned components. More concretely, a user generally annotates resources with different forms of user generated content, like social annotations, tags or links. As a consequence, huge amounts of shared social data are now available, which raises new challenges for information management and discovery. Each social interaction represents an opportunity to create valuable knowledge that can be further leveraged for added-value services (e.g. recommendation or prediction)

Italie

Équipe du CDPC Jean-Claude Escarras, Baudrez Maryse, Di Manno Thierry, Pardini Jean-Jacques, Ravaz Bruno, Elie Marie-Pierre, Jacquelot Fanny, Schmitt Sylvie, Severino Caterina, Giudicelli Julien, Bourilhon Grégory, Pereon Patrick, Martello C., Aubert S., Durand E., Falduto Jean-Baptiste, Morales V., Roudier Karine, Picault L., Bardin Michaël, Pennec Laurent, Santolini Thierry. Italie. In: Annuaire international de justice constitutionnelle, 21-2005, 2006. Constitutions nationales et Constitution européenne – Autonomies locales et Constitutions. pp. 583-642