VIII Conference on Mechanical Response of Composites最新文献

{"title":"Fiber Break Model for Unidirectional Composites in Tension-Tension Fatigue.","authors":"B. Fazlali, S. Lomov, Y. Swolfs","doi":"10.23967/composites.2021.059","DOIUrl":"https://doi.org/10.23967/composites.2021.059","url":null,"abstract":"","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129361428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Framework for Homogenizing Poly-crystalline Silicon Wafers Including Pre-cracks","authors":"M. Tariq, C. Gerendt, S. Scheffler, R. Rolfes","doi":"10.23967/composites.2021.052","DOIUrl":"https://doi.org/10.23967/composites.2021.052","url":null,"abstract":"The Photovoltaic (PV) modules are being utilized in novel and diverse ways in recent years. Many experimental investigations are under development in which they are being designed to be applied in extreme environments, e.g. on the wing surface of aircrafts [1] or on the facets of building [2]. During these applications, PV modules undergo high wind loads. A PV module consists of several solar cells. The most critical component of a solar cell is the brittle poly-crystalline silicon wafer, which is prone to fracture even under moderate loads. The micro-cracks in a silicon wafer deteriorate the capability of the solar cell reducing the production of the electric current. The numerical analysis of the extent of such micro-cracks (at the crystal level) in silicon wafers is, therefore, crucial to assess the potential electric yield of the PV modules but also computationally expensive due to the high degree of anisotropy. In order to reduce the computational costs, solar cells can be homogenized using effective material properties of the representative volume element (RVE). By such a homogenization approach, the degrees of freedom are reduced significantly, yielding a reduced-order model of the PV modules [3]. Some methodologies were already proposed to determine such effective material properties successfully for composite plates or laminas [4]. In this contribution, a virtual framework is developed that incorporates these homogenization techniques in combination with the finite element methods in ABAQUS/Implicit for efficient numerical assessment of the PV module. The framework homogenizes the elastic material properties of the polycrystalline microstructure, as well as trans/intra-granular fracture for a complete silicon cell. The homogenization of fracture subsequently yields damage parameters for the homogenized solar cell. As a result, the framework provides a good basis for","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126058611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparing Acceleration Techniques for FE2: Classic Mesoscale Modeling, Black-Box Data-Driven Modeling and Physics-Informed Hyper-Reduction","authors":"I. Rocha, P. Kerfriden, F. Meer","doi":"10.23967/composites.2021.101","DOIUrl":"https://doi.org/10.23967/composites.2021.101","url":null,"abstract":".","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125513963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micromechanical Interaction Model Accounting for the Spatial Distribution of Inclusions in Elastic-Viscoplastic Composites","authors":"K. Kowalczyk-Gajewska, M. Majewski, S. Mercier, A. Molinari","doi":"10.23967/composites.2021.034","DOIUrl":"https://doi.org/10.23967/composites.2021.034","url":null,"abstract":"","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127935945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Homogenization of Nonlinear Viscoelastic Three-Phase Particulate Composites","authors":"J. Fauque, R. Masson, M. Gărăjeu","doi":"10.23967/composites.2021.039","DOIUrl":"https://doi.org/10.23967/composites.2021.039","url":null,"abstract":"","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129969203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Visco-Plastic Behaviour of a Polymer Matrix at the Fibre Diameter Length Scale: a Finite Element Mesoscale Model Relying on Shear Transformation Zone (STZ) Dynamics","authors":"M. Fagerström, G.Catalanotti, Nathan Klavzer, F. Loock, Jérémy Chevalier, L. Brassart, Thomas Pardoen","doi":"10.23967/composites.2021.062","DOIUrl":"https://doi.org/10.23967/composites.2021.062","url":null,"abstract":"Polymeric glasses exhibit complex behaviour when subjected to deformation below the glass transition temperature. Uniaxial stress-strain curves typically include post-yield strain softening, strain hardening, and non-linear unloading. In addition, the deformation and failure responses are sensitive to the rate of deformation, pressure, and temperature. Sophisticated (visco-)elastic-(visco-)plastic continuum constitutive models have been developed to simulate the large strain deformation of (glassy) polymers; they generally give excellent fits to uniaxial stress-strain curves. However, they require the calibration of a large number of mostly phenomenological parameters, give limited insights into failure, and struggle to accurately predict the response for more complicated loading states and histories. At the opposite scale, molecular dynamics (MD) simulations have been used to elucidate the discrete molecular deformation mechanisms leading to the heterogeneous inelastic behaviour of polymeric glasses. The results of MD calculations suggest that plastic deformation of polymeric glasses is caused by thermally activated molecular rearrangements and conformational changes of a collection of polymer chains parts. The use of a mesoscale numerical model based on the activation of shear transformation zones (STZs) offers a convenient approach to bridge continuum and molecular dynamics simulations, which are typically limited to small length and time scales. We have used the implementation by Homer and Schuh","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125570247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Viscoelastic Cohesive Law for Rate and Temperature Dependent Mixed Mode Delamination","authors":"G. Sengodan, G. Allegri, S. Hallett","doi":"10.23967/composites.2021.030","DOIUrl":"https://doi.org/10.23967/composites.2021.030","url":null,"abstract":"Interlaminar failure of laminated composites is adequately described using bilinear/exponential cohesive zone modelling (CZM) simulations. However, state-of-the-art CZM formulations do not account for the environmental conditions that composite structures encounter in-service. Further enhancements of CZM models are required to account the effects of temperature and strain rate on the delamination behaviour. These effects could be modelled via fitting experimental trends, but such an approach would not provide a comprehensive explanation of the underlying physical mechanisms. In this work, a cohesive zone modelling framework that accounts the effect of loading rate and temperature on the interlaminar failure of laminated composites is presented. The loading and softening part of the traction-separation curve is represented by using the generalized Maxwell model, while the Zhurkov ’s kinetic theory of failure [1] is employed to describe progressive damage growth. The corresponding rheological elements introduced for a mixed mode-delamination are illustrated in Figure 1(a).","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126711234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Damping in CFRP Structures: Modelling and Comparison of Technological Solutions Using Elastomer","authors":"Y. Archi, N. Lahellec, S. Lejeunes, A. Jouan, B. Tranquart","doi":"10.23967/composites.2021.003","DOIUrl":"https://doi.org/10.23967/composites.2021.003","url":null,"abstract":"In aeronautics, the latest generations of turbojets have inlet fan blades made of 3D-woven carbon fibre composite. Damping of rotating structures, such as blades, is of major industrial concern for controlling vibratory instabilities, like in-flight flutter for example, which can lead to the degradation of these blades. In order to overcome this difficulty and because CFRP materials are known to have limited damping properties, it seems necessary to implement innovative solutions to improve such a structure’s damping. Here, we study three damping technologies, based on the introduction of a dissipative material (elastomer) in the structure: The first technology consists in the bonding of an elastomeric layer at the scale of the blade structure which is also known as the viscoelastic patch (see [1]). Here the solution studied is a particular case of this technology where the elastomer layer lies within the laminate. The second technology consists in the introduction of the elastomer at the microstructure scale by adding some elastomeric fibers in the carbon fabric (see for example [2]). In the last one, still at the microstructure scale, all the carbon fibers are coated with a thin layer of elastomer ([3]). In the present study, some multiscale simulations are done to demonstrate the ability of these techniques to damp the first eigenfrequency of a cantilever beam, also known as Oberst beam tests ([4]). The constitutive materials (epoxy matrix and elastomer) are modelled in the framework of linear viscoelasticity, the plies behaviour are obtained by numerical homogenization and the laminate response is obtained by finite element method analysis (≪ Steady-State Dynamics ≫ procedure, ABAQUS V6.14). The results show that for a quasi-isotropic laminate stacking sequence, [−45,90,45,0]s, the ”coated” and ”co-fabric” technologies succeed in damping the first eigenmode but the damping ratio obtained with both techniques are lower than those obtained with the patch method (all the results are obtained with the same amount of added elastomer).","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"300 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122044469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional Composites for Energy Harvesting Applications with Low-Frequency Magnetic Actuation","authors":"M. Rosso, R. Ardito, A. Corigliano","doi":"10.23967/composites.2021.047","DOIUrl":"https://doi.org/10.23967/composites.2021.047","url":null,"abstract":"The increasing necessity of IoT, encouraged the research world to develop MEMS autonomous sensors in order to create a large network of smart communicating devices. To this purpose a possible solution lies in the exploitation of the environmental kinetic energy for generating electrical energy through piezoelectric vibration energy harvesting systems [1], [2]. These functional structures, at the MEMS scale, are characterized by high natural frequency of vibration in contrast to the typical frequencies of the environment that are very small. Due to this mismatch, the vibration of the harvester is in practice not activated and very low levels of electrical energy can be obtained. In order to solve this problem, an efficient technique to up-convert the frequency of the input signal through magnetic interaction is here presented as also proposed in [3]. A theoretical and computational study is performed on a high-frequency layered piezoelectric cantilever with a silicon substrate and a PZT functional layer. This choice of laminate is fully compatible with the current micromachining process in which the deposition of the active layer is made by sol-gel or sputtering techniques. Dynamic analyses are performed under different input conditions of motion and the frequency up-conversion (FuC) occurs due to the interaction of the cantilever with a low frequency mass through Neodymium permanent magnets. Beyond the FuC mechanism, also an experimental investigation of the magnetic interaction is presented, pointing out some critical issues of typical analytical approaches with respect to real physics in terms of energy. This reflects on the performance of the functional structure.","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128744015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Simulations of Dynamic Delamination In [05/903]S CFRP Beams Subjected To Transverse Impact","authors":"M. Fagerström, G.Catalanotti, D. Coker, M. Bozkurt, Ercan Gurses","doi":"10.23967/composites.2021.114","DOIUrl":"https://doi.org/10.23967/composites.2021.114","url":null,"abstract":"Composite materials are widely used in aerospace structures as they offer advantageous mechanical properties such as high in-plane strength and stiffness-to-weight ratios. However, when subjected to transverse impact, composites show internal failures, such as delamination and matrix cracking, which may lead to a considerable loss of in-plane stiffness and strength. Therefore, accurate modelling of impact induced damage in composite laminates is an important issue to consider in design. In the recent experimental study of the authors [1], the initiation and propagation of the dynamic delamination were captured real-time by a high-speed camera at 525,000 and reported. It was also suggested that the experimental data consisting of the crack tip positions and the crack tip speeds might be used as a benchmark to fine-tune interlaminar damage models of cross-ply composite laminates. In this study, numerical simulations of these experiments are simulated using the finite element method. The finite element simulations are conducted in ABAQUS/Explicit. Matrix damage is simulated through the continuum damage model proposed by the authors [2], which is implemented into the ABAQUS via a user-written subroutine VUMAT. Cohesive zone method is used to simulate delamination damage. Results of the simulations are in good agreement with the experiments in terms of the damage form, the initiation location and time. Comparing the delamination propagation speeds from the in-situ experiments and the simulations as shown in Figure 1, it is propounded that the dynamic values of interface properties including interlaminar strength and fracture toughness may have an effect on the accuracy of dynamic failure simulations.","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128647896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}