VIII Conference on Mechanical Response of Composites最新文献_第4页

Automated Model Generation of Large Wind Turbine Blades: Advantage of Solid over Shell Elements 大型风力涡轮机叶片的自动模型生成:实体比壳单元的优势

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.075

R. Tavares, W. Paepegem

{"title":"Automated Model Generation of Large Wind Turbine Blades: Advantage of Solid over Shell Elements","authors":"R. Tavares, W. Paepegem","doi":"10.23967/composites.2021.075","DOIUrl":"https://doi.org/10.23967/composites.2021.075","url":null,"abstract":"Due to market demand the size of wind turbines has been rapidly increasing due to the expected reduction in cost of energy for larger turbines. This leads to blades of extreme complexity, both in terms of geometry and materials. The increased structural complexity of larger turbines requires a better understanding of their behaviour, thus demanding the usage of higher ﬁdelity numerical models. The behaviour of these structures is usually investigated using Outer Mold Layer (OML) shell models, however different studies have identiﬁed signiﬁcant drawbacks of this approach. One of the drawbacks is related with the mechanical response of the blade under torsional loads, which shows a lower stiffness when simulated using OML based shell elements when compared to solid elements [1]. The second issue with the shell approach is related to the correct representation of the adhesive joints in the blade, since the inner surfaces that make contact with the adhesive are not directly modelled. This is usually resolved by changing the geometry of the modelled adhesive and scaling its stiffness, ensuring the correct stiffness of the blade’s section, or by using multi-point constraints to connect the adhesive with the OML shell. Finally, the usage of solid elements allows a better representation of the stress state within the composite materials, which increases its ﬁdelity and is essential when predicting damage progression and failure. In this work, a novel approach to create FE blade models, which allows both shell, solid and hybrid modelling strategies to be employed is presented","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131875446","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}

引用次数: 0

An Adaptive Floating Node Based Formulation for Progressive Fatigue Analysis of Multiple Delaminations 基于自适应浮动节点的多层逐级疲劳分析公式

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.046

G. Trabal, B. Bak, B. Chen, E. Lindgaard

{"title":"An Adaptive Floating Node Based Formulation for Progressive Fatigue Analysis of Multiple Delaminations","authors":"G. Trabal, B. Bak, B. Chen, E. Lindgaard","doi":"10.23967/composites.2021.046","DOIUrl":"https://doi.org/10.23967/composites.2021.046","url":null,"abstract":"Fatigue-driven delamination is one of the main damage modes leading to the ﬁnal failure of composite laminated structures. Great advances have been achieved in recent years on accurate modelling of delamination onset and growth under fatigue loading by the use of Cohesive Zone Models (CZM) integrated into cohesive interface ﬁnite elements. Although the implementation of such models in Finite Elements Analysis (FEA) through decohesion elements is available in literature and research codes, resulting models are still computationally expensive and require intensive modelling work by the user. These disadvantages make the simulation of multiple delaminations on a general layup at the structural level an impossible task. A new analysis methodology named the Floating Node Method (FNM) has recently been proposed [1] that has the potential to overcome these issues. In this work, a new numerical fatigue formulation based on an FNM enhanced element and a new adaptive reﬁnement scheme is presented. The FNM-based element is capable of including new cohesive elements at any interface in the model as well as reﬁning existing elements without the use of remeshing. The adaptive reﬁnement scheme is based on local information at the element level, i.e. damage state, without hard-coded and problem-dependent user inputs. The suggested adaptive reﬁnement scheme successfully reﬁne and coarse the mesh adaptively as well as, include CZ elements at needed interfaces during the iterative solution procedure rendering the solution accurate and efﬁcient. The delamination growth in the different interfaces is accounted for using a fatigue model based on [2] which combines a quasi-static","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132222847","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}

引用次数: 0

Simulation of Lightning-Induced Mechanical Damage in CFRP Laminates CFRP层合板雷击机械损伤模拟

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.077

A. Arteiro, D. Alonso, C. Karch, P. Camanho

引用次数: 0

Probabilistic Failure Prediction under Combined in-plane Compression-Shear Loading for Unidirectional Fiber Reinforced Composites 单向纤维增强复合材料面内压剪联合载荷下的概率破坏预测

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.049

N. Safdar, B. Daum, S. Scheffler, R. Rolfes

引用次数: 0

Mode I fracture Assessment of Adhesively Bonded Non-Crimp Fabric Carbon Fiber/Epoxy Composite Joints 无卷曲织物碳纤维/环氧复合材料粘接接头的I型断裂评价

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.072

R. Dehaghani, D. Cronin, J. Montesano

引用次数: 0

Microscale Analysis of the Influence of Void Content, Distribution and Size on Fiber-Reinforced Polymers 孔隙含量、分布和尺寸对纤维增强聚合物影响的微观分析

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.066

O. Vallmajó, A. Turón, A. Arteiro

{"title":"Microscale Analysis of the Influence of Void Content, Distribution and Size on Fiber-Reinforced Polymers","authors":"O. Vallmajó, A. Turón, A. Arteiro","doi":"10.23967/composites.2021.066","DOIUrl":"https://doi.org/10.23967/composites.2021.066","url":null,"abstract":"The increasing demand for Fiber-Reinforced Polymers (FRPs) for lightweight structures requires efficient manufacturing processes. However, predicting defect formation during production and the effect on the mechanical performance is still a matter of concern. One of the main challenges for FRPs is the difficulty to predict their mechanical behavior due to the complex deformation and failure mechanisms, the presence of defects and the intrinsic variability of the material properties. At the microscale, the properties of the constituents, their spatial distribution and the defects arising from manufacturing play a critical role in the damage development. Thus, the experimental characterization of the damage onset and development is a very difficult and expensive task. However, accurate numerical simulations with advanced constitutive models can help understanding the mechanical behavior at the microscale (constituents level) and their translation to the mesoscale properties (ply level). To that end, a Representative Volume Element (RVE) of the composite material needs to be defined. In this work, a computational micromechanical model is proposed and analyzed using a Finite Element (FE) software to determine the effect of defects, specifically voids, on the mechanical properties of FRPs. The fibers are randomly distributed in a micromechanical 3-D RVE in accordance to the fiber volume fraction, following the methods proposed in Refs. [1, 2]. In the same way, the voids are distributed in the RVE according to the void content and their characteristic parameters. A parametric analysis is performed to analyze the effect of the main characteristics of the voids as described in Ref. [3], such as the spatial distribution, the void content and the void size, on the homogenized mechanical properties at the ply level.","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115069336","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}

引用次数: 0

Improvement of Translaminar Toughness of Composite Materials through Pseudo-Ductility 利用拟延性提高复合材料的跨层韧性

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.103

A. Subramani, Pere MaimÃ, J. Costa

引用次数: 0

A Multi-Scale Modelling Approach Predicting the Effect of Porosity on the Transverse Strength in Composites 孔隙率对复合材料横向强度影响的多尺度建模方法

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.093

B. Fisher, M. Eaton, R. Pullin

引用次数: 0

Key Issues in a Benchmarking Exercise for Longitudinal Tensile Failure of Unidirectional Composites 单向复合材料纵向拉伸破坏基准测试中的关键问题

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.096

C. Breite, A. Melnikov, F. Mesquita, S. Lomov, Y. Swolfs

{"title":"Key Issues in a Benchmarking Exercise for Longitudinal Tensile Failure of Unidirectional Composites","authors":"C. Breite, A. Melnikov, F. Mesquita, S. Lomov, Y. Swolfs","doi":"10.23967/composites.2021.096","DOIUrl":"https://doi.org/10.23967/composites.2021.096","url":null,"abstract":"Longitudinal tensile failure of unidirectional plies is a key failure mode for laminated composites. We therefore organised a benchmarking exercise with 7 participating models, where the models were carefully compared against each other based on two virtual materials [1]. We also performed a detailed experimental validation study for 6 of the participating models, based on synchrotron computed tomography data for fibre break development combined with carefully and objectively measured input data. The present paper analyses where the discrepancies between models and experiments may have arisen from, based on the KU Leuven strength model [1]. Fig. 1 for example shows how the scatter in the experimental fibre break density evolutions is similar to the scatter in the Monte Carlo simulations. The scatter bands however do not overlap. We also fitted a Weibull distribution to the fibre break density evolution (excluding clusters of fibre breaks). Running simulations with the fitted Weibull distribution as input revealed that a good agreement between the density developments can be achieved. However, even a fitted Weibull distribution still leads to significant errors in other parameters, such as tensile strength or cluster evolution. The complete analysis of all key issues has shown that the discrepancies cannot be attributed to any single input parameter or assumption, such as the Weibull distribution, but should be attributed to a combination of unknowns that need to be explored in further studies.","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"160 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122862708","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}

引用次数: 0

Modelling the Rate- and Temperature-Dependent Micro-Mechanical Behaviour of Carbon Fiber Reinforced PVDF 碳纤维增强PVDF的速率和温度相关微观力学行为建模

VIII Conference on Mechanical Response of Composites Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.063

T. Lenders, J. Remmers, T. Pini, L. Govaert, M. Geers

{"title":"Modelling the Rate- and Temperature-Dependent Micro-Mechanical Behaviour of Carbon Fiber Reinforced PVDF","authors":"T. Lenders, J. Remmers, T. Pini, L. Govaert, M. Geers","doi":"10.23967/composites.2021.063","DOIUrl":"https://doi.org/10.23967/composites.2021.063","url":null,"abstract":"The conditions to which ﬁber reinforced plastics (FRPs) are exposed in state of the art applications are becoming more extreme, for example in the offshore oil and gas industry. Therefore, the ability to predict the long-term behaviour, and thereby identifying the failure mechanisms, of ﬁber reinforced plastics is of great importance. Especially under these extreme conditions, the contribution of the matrix plays an important role and a detailed description of its behaviour is required. In oil and gas applications, polyvinylidene ﬂuoride (PVDF) is used because of its excellent gas barrier properties. In this work the rate-and temperature-dependent micro-mechanical behaviour of carbon ﬁber reinforced polyvinylidene ﬂuoride is studied. The behaviour of the composite is studied by using a micro-mechanical model that is composed of individually modelled carbon ﬁbers embedded in a PVDF matrix. The time-and temperature-dependent behaviour of PVDF is captured by the Eindhoven Glassy Polymer (EGP) constitutive model [1]. This model enables the description of the intrinsic behaviour of the semi-crystalline matrix over a range of applied strain rates and temperatures using a single set of material parameters. The characterization of these material parameters, requires a set of experimental data obtained from uniaxial compression and tensile tests performed at different temperatures and applied strain rates. To describe the material behaviour of the individually modelled carbon ﬁbers, an elastic orthotropic material model is employed. Off-axis tensile tests of the composite led to the observation that the interface behaviour between matrix and ﬁber must be incorporated in the micro-mechanical model as well. Subsequently, an interface between the matrix and ﬁber is added to the model by using cohesive zone interface elements. The behaviour of these interface elements is described by an appropriate constitutive","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128179347","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}

引用次数: 0