首页 > 最新文献

VIII Conference on Mechanical Response of Composites最新文献

英文 中文
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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.075
R. Tavares, W. Paepegem
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
由于市场的需求,风力涡轮机的规模已经迅速增加,由于预期降低能源成本的大型涡轮机。这导致叶片在几何形状和材料方面都极其复杂。大型涡轮机结构复杂性的增加需要更好地理解它们的行为,因此要求使用更高保真度的数值模型。这些结构的行为通常使用外模层(OML)壳模型进行研究,然而不同的研究已经确定了这种方法的显着缺点。其中一个缺点与叶片在扭转载荷下的机械响应有关,与实体单元相比,使用基于OML的壳单元模拟时,其刚度较低[1]。壳体方法的第二个问题与叶片中粘合剂接头的正确表示有关,因为与粘合剂接触的内表面没有直接建模。这通常是通过改变建模粘合剂的几何形状和缩放其刚度来解决的,确保叶片部分的正确刚度,或者通过使用多点约束将粘合剂与OML外壳连接起来。最后,使用固体单元可以更好地表示复合材料中的应力状态,这增加了其保真度,并且在预测损伤进展和失效时至关重要。在这项工作中,提出了一种创建FE叶片模型的新方法,该方法允许使用壳,实体和混合建模策略
{"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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.046
G. Trabal, B. Bak, B. Chen, E. Lindgaard
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
疲劳驱动脱层是导致复合材料层合结构最终失效的主要损伤形式之一。近年来,结合黏性界面有限元的黏性区模型(CZM)在疲劳载荷下的分层发生和发展的精确建模方面取得了很大进展。尽管在文献和研究代码中可以通过解聚元素在有限元分析(FEA)中实现这种模型,但由此产生的模型仍然需要大量的计算成本,并且需要用户进行大量的建模工作。这些缺点使得在结构层面上对一般层的多重分层进行模拟成为不可能完成的任务。最近提出了一种名为浮动节点法(FNM)的新分析方法[1],它有可能克服这些问题。本文提出了一种新的基于FNM增强单元的疲劳数值公式和一种新的自适应细化方案。基于fnm的元素能够在模型的任何接口上包含新的内聚元素,并在不使用重网格的情况下精炼现有元素。自适应改进方案基于元素级别的局部信息,即损坏状态,不需要硬编码和问题相关的用户输入。所提出的自适应细化方案成功地对网格进行了自适应细化和粗化,并在迭代求解过程中在需要的接口处包含了CZ元素,使求解更加准确和高效。使用基于[2]的准静态疲劳模型来解释不同界面中的分层生长
{"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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.077
A. Arteiro, D. Alonso, C. Karch, P. Camanho
{"title":"Simulation of Lightning-Induced Mechanical Damage in CFRP Laminates","authors":"A. Arteiro, D. Alonso, C. Karch, P. Camanho","doi":"10.23967/composites.2021.077","DOIUrl":"https://doi.org/10.23967/composites.2021.077","url":null,"abstract":"","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":"127478700","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
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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.049
N. Safdar, B. Daum, S. Scheffler, R. Rolfes
One of the design limiting failure for fiber reinforced composites (FRC) is under compression loads, showing failure under compression at as low as two thirds of their tensile strengths. Over the past few decades numerous analytical, experimental and numerical investigations have explored different dimensions of the problem [1]. It is now widely accepted that the dominant factors behind compression dominated failure modes are manufacturing induced fiber misalign-ments and the nonlinear matrix material behavior. Uncertainty regarding fiber misalignment leads to variations in strengths under compression dominated loads [2]. In order to exploit the maximum potential of FRCs, it is essential to predict the failure under axial compression and compression dominated combined loads reliably. In order to advance the understanding of the problem in this direction
纤维增强复合材料(FRC)的设计极限失效之一是在压缩载荷下,在低至其抗拉强度的三分之二的压缩下失效。在过去的几十年里,大量的分析、实验和数值研究探索了这个问题的不同维度[1]。目前,人们普遍认为压缩主导失效模式背后的主要因素是制造引起的纤维错位和非线性基体材料行为。纤维错位的不确定性导致在压缩主导载荷下强度的变化[2]。为了发挥frp的最大潜力,对其在轴压和压缩主导组合荷载作用下的破坏进行可靠的预测是至关重要的。为了在这个方向上推进对问题的理解
{"title":"Probabilistic Failure Prediction under Combined in-plane Compression-Shear Loading for Unidirectional Fiber Reinforced Composites","authors":"N. Safdar, B. Daum, S. Scheffler, R. Rolfes","doi":"10.23967/composites.2021.049","DOIUrl":"https://doi.org/10.23967/composites.2021.049","url":null,"abstract":"One of the design limiting failure for fiber reinforced composites (FRC) is under compression loads, showing failure under compression at as low as two thirds of their tensile strengths. Over the past few decades numerous analytical, experimental and numerical investigations have explored different dimensions of the problem [1]. It is now widely accepted that the dominant factors behind compression dominated failure modes are manufacturing induced fiber misalign-ments and the nonlinear matrix material behavior. Uncertainty regarding fiber misalignment leads to variations in strengths under compression dominated loads [2]. In order to exploit the maximum potential of FRCs, it is essential to predict the failure under axial compression and compression dominated combined loads reliably. In order to advance the understanding of the problem in this direction","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"48 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":"131073203","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
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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.072
R. Dehaghani, D. Cronin, J. Montesano
{"title":"Mode I fracture Assessment of Adhesively Bonded Non-Crimp Fabric Carbon Fiber/Epoxy Composite Joints","authors":"R. Dehaghani, D. Cronin, J. Montesano","doi":"10.23967/composites.2021.072","DOIUrl":"https://doi.org/10.23967/composites.2021.072","url":null,"abstract":"","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"1 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":"128260263","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
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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.066
O. Vallmajó, A. Turón, A. Arteiro
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.
轻量化结构对纤维增强聚合物(frp)的需求日益增长,这需要高效的制造工艺。然而,预测生产过程中缺陷的形成及其对机械性能的影响仍然是一个值得关注的问题。frp的主要挑战之一是由于其复杂的变形和破坏机制、缺陷的存在以及材料性能的内在变异性,难以预测其力学行为。在微观尺度上,构件的性质、空间分布和制造过程中产生的缺陷对损伤的发展起着至关重要的作用。因此,损伤发生和发展的实验表征是一项非常困难和昂贵的任务。然而,利用先进的本构模型进行精确的数值模拟可以帮助理解微观尺度(组分水平)的力学行为及其向中尺度(层)性质的转化。为此,需要定义复合材料的代表性体积单元(RVE)。在这项工作中,提出了一个计算微力学模型,并使用有限元(FE)软件进行分析,以确定缺陷,特别是空隙对frp力学性能的影响。按照参考文献中提出的方法,将纤维按照纤维体积分数随机分布在微机械三维RVE中。[1,2]。同样,孔洞在RVE中的分布也根据孔洞含量及其特征参数进行。通过参数化分析,分析文献[3]中描述的孔洞的主要特征(如空间分布、孔洞含量和孔洞尺寸)对铺层均质力学性能的影响。
{"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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.103
A. Subramani, Pere MaimÃ, J. Costa
{"title":"Improvement of Translaminar Toughness of Composite Materials through Pseudo-Ductility","authors":"A. Subramani, Pere MaimÃ, J. Costa","doi":"10.23967/composites.2021.103","DOIUrl":"https://doi.org/10.23967/composites.2021.103","url":null,"abstract":"","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"28 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":"124558201","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
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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.093
B. Fisher, M. Eaton, R. Pullin
To validate the model, laminates with differing porosity were manufactured. Specimens were subjected to compressive testing and found to have a 10.5% reduction in strength. Microscopy was used to generate unit cells and the modelling process described in Section 2 was followed providing a model correlation of over 95.2%. The experimental and modelling results can be seen in Figure. 1. Once validated, the model was used to show a reduction in tensile strength from 60.5 MPa to 50.6 MPa.
为了验证该模型,制作了不同孔隙率的层压板。试样进行压缩测试,发现强度降低了10.5%。显微镜用于生成单元细胞,并遵循第2节中描述的建模过程,提供超过95.2%的模型相关性。实验和建模结果如图1所示。经过验证后,该模型显示抗拉强度从60.5 MPa降至50.6 MPa。
{"title":"A Multi-Scale Modelling Approach Predicting the Effect of Porosity on the Transverse Strength in Composites","authors":"B. Fisher, M. Eaton, R. Pullin","doi":"10.23967/composites.2021.093","DOIUrl":"https://doi.org/10.23967/composites.2021.093","url":null,"abstract":"To validate the model, laminates with differing porosity were manufactured. Specimens were subjected to compressive testing and found to have a 10.5% reduction in strength. Microscopy was used to generate unit cells and the modelling process described in Section 2 was followed providing a model correlation of over 95.2%. The experimental and modelling results can be seen in Figure. 1. Once validated, the model was used to show a reduction in tensile strength from 60.5 MPa to 50.6 MPa.","PeriodicalId":392595,"journal":{"name":"VIII Conference on Mechanical Response of Composites","volume":"77 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":"116480474","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
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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.096
C. Breite, A. Melnikov, F. Mesquita, S. Lomov, Y. Swolfs
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.
单向层纵向拉伸破坏是层合复合材料的一种重要破坏模式。因此,我们组织了一个有7个参与模型的基准测试练习,其中模型基于两种虚拟材料[1]仔细地相互比较。我们还对6个参与模型进行了详细的实验验证研究,基于纤维断裂发育的同步加速器计算机断层扫描数据结合仔细客观测量的输入数据。本文基于KU Leuven强度模型[1],分析了模型与实验之间的差异可能来自何处。例如,图1显示了实验纤维断裂密度演化中的散射与蒙特卡罗模拟中的散射是如何相似的。然而,散射带并不重叠。我们还拟合了纤维断裂密度演变的威布尔分布(不包括纤维断裂簇)。用拟合的威布尔分布作为输入进行模拟表明,密度发展之间可以达到很好的一致性。然而,即使一个拟合的威布尔分布仍然会导致其他参数的显著误差,如抗拉强度或聚类演化。对所有关键问题的完整分析表明,差异不能归因于任何单一的输入参数或假设,如威布尔分布,而应归因于未知因素的组合,这些未知因素需要在进一步的研究中加以探索。
{"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
Pub Date : 2021-09-01 DOI: 10.23967/composites.2021.063
T. Lenders, J. Remmers, T. Pini, L. Govaert, M. Geers
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
纤维增强塑料(frp)在最先进的应用中暴露的条件变得越来越极端,例如在海上石油和天然气工业中。因此,预测纤维增强塑料的长期行为,从而确定其破坏机制的能力是非常重要的。特别是在这些极端条件下,矩阵的贡献起着重要的作用,需要对其行为进行详细的描述。在石油和天然气应用中,聚偏氟乙烯(PVDF)因其优异的气体阻隔性能而被使用。本文研究了碳纤维增强聚偏氟乙烯的微观力学行为随温度和速率的变化规律。复合材料的行为通过使用微观力学模型来研究,该模型是由嵌入PVDF矩阵的单独建模碳纤维组成的。PVDF的时间和温度依赖行为被埃因霍温玻璃聚合物(EGP)本构模型捕获[1]。该模型能够使用一组材料参数描述半晶基体在一系列施加应变率和温度下的固有行为。这些材料参数的表征需要一组实验数据,这些数据来自在不同温度和施加应变速率下进行的单轴压缩和拉伸试验。为了描述单独建模的碳纤维的材料行为,采用了弹性正交各向异性材料模型。复合材料的离轴拉伸试验表明,基体和纤维之间的界面行为也必须纳入微观力学模型。随后,利用内聚区界面元在模型中加入了基体与纤维之间的界面。这些界面元素的行为由一个适当的本构来描述
{"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
期刊
VIII Conference on Mechanical Response of Composites
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1