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【新文速递】2024年12月27日固体力学SCI期刊最新文章

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今日更新:International Journal of Solids and Structures 1 篇,Journal of the Mechanics and Physics of Solids 2 篇,International Journal of Plasticity 1 篇,Thin-Walled Structures 2 篇

International Journal of Solids and Structures

Phase transition resistance induced by locally resonant metastructures

Peng-Cheng Qi, Yi-Ze Wang

doi:10.1016/j.ijsolstr.2024.113209

局部共振元结构引起的相变电阻

Based on the piecewise linear relation between the force and elongation of springs, the phase transition and its generating waves in mechanical metastructures are studied. With the Wiener-Hopf method, the governing equation of the transition wave is derived. External force compensations for defect springs are considered to describe the phase transition. Besides the condition that whether the phase transition can be generated, localized phase transition is discussed. Furthermore, finite element simulation and experiment are performed to show the dynamic phase transition. It can be concluded that the locally resonant metastructures can enhance the resistance of phase transition. This research is expected to be helpful to design new kinds of elastic wave metastructures and metamaterials to improve phase transition strength.

基于弹簧的力与伸长率的分段线性关系,研究了力学元组织中的相变及其产生波。利用Wiener-Hopf方法,推导了过渡波的控制方程。考虑了缺陷弹簧的外力补偿来描述相变。除了能不能产生相变的条件外,还讨论了局域相变。在此基础上,进行了有限元模拟和实验研究。结果表明,局部共振的元结构可以增强相变的阻力。本研究对设计新型弹性波超结构和提高相变强度的超材料具有一定的指导意义。


Journal of the Mechanics and Physics of Solids

Multiscale analysis method for profiled composite structures considering the forming process

Chen Liu, Jingran Ge, Shuwei Zhao, Qi Zhang, Xiaodong Liu, Jun Liang

doi:10.1016/j.jmps.2024.106014

考虑成形过程的复合材料异型结构多尺度分析方法

The forming process often results in a highly heterogeneous mesoscale structure within composite structures, leading to enormous changes in mechanical properties. This complexity poses a significant challenge for accurately evaluating their mechanical behavior. In this paper, a concurrent multiscale analysis method considering the forming process is proposed to accurately analyze the mechanical behavior of profiled composite structures. The change in the internal mesoscale structure of the profiled composite structures is studied by simulating the preforming process of the composite woven fabric. A feature reduction scheme is proposed to reduce the multiscale model of profiled composite structures based on shear angle γ (selected as feature of the U-shape composite structure) and each feature region is coupled with a corresponding mesoscale model. Subsequently, a concurrent multiscale simulation method, based on self-consistent clustering analysis, is developed to model the mechanical behavior of profiled composite structures. The proposed method for simulation of profiled composite structures is validated against experimental data from literature covering various shear deformations. Finally, the progressive failure analysis of the U-shape composite structure (an example) is implemented to reveal its failure mechanism at both macroscale and mesoscale scales. The proposed multiscale analysis method can be applied to the structural design and the optimization of composite forming process.

成形过程往往导致复合材料结构内部形成高度不均匀的中尺度结构,从而导致力学性能的巨大变化。这种复杂性对准确评估其机械行为提出了重大挑战。本文提出了一种考虑成形过程的并行多尺度分析方法,以精确分析复合材料异型结构的力学行为。通过模拟复合机织物的预成形过程,研究了异形复合材料结构内部中尺度结构的变化。提出了一种基于剪切角γ(选择u型复合材料结构的特征)的特征约简方案,并将每个特征区域与相应的中尺度模型耦合。在此基础上,提出了一种基于自洽聚类分析的并行多尺度模拟方法来模拟复合材料异型结构的力学行为。本文提出的模拟复合材料异型结构的方法与文献中涵盖各种剪切变形的实验数据进行了验证。最后,以u型复合材料结构为例进行了递进破坏分析,揭示了其宏观和中尺度的破坏机制。所提出的多尺度分析方法可应用于复合材料的结构设计和成形工艺优化。


Consistent machine learning for topology optimization with microstructure-dependent neural network material models

Harikrishnan Vijayakumaran, Jonathan B. Russ, Glaucio H. Paulino, Miguel A. Bessa

doi:10.1016/j.jmps.2024.106015

基于微结构相关神经网络材料模型的拓扑优化一致机器学习

Additive manufacturing methods together with topology optimization have enabled the creation of multiscale structures with controlled spatially-varying material microstructure. However, topology optimization or inverse design of such structures in the presence of nonlinearities remains a challenge due to the expense of computational homogenization methods and the complexity of differentiably parameterizing the microstructural response. A solution to this challenge lies in machine learning techniques that offer efficient, differentiable mappings between the material response and its microstructural descriptors. This work presents a framework for designing multiscale heterogeneous structures with spatially varying microstructures by merging a homogenization-based topology optimization strategy with a consistent machine learning approach grounded in hyperelasticity theory. We leverage neural architectures that adhere to critical physical principles such as polyconvexity, objectivity, material symmetry, and thermodynamic consistency to supply the framework with a reliable constitutive model that is dependent on material microstructural descriptors. Our findings highlight the potential of integrating consistent machine learning models with density-based topology optimization for enhancing design optimization of heterogeneous hyperelastic structures under finite deformations.

增材制造方法与拓扑优化相结合,可以创建具有可控空间变化材料微观结构的多尺度结构。然而,由于计算均匀化方法的费用和微结构响应微分参数化的复杂性,在非线性存在的情况下,这种结构的拓扑优化或反设计仍然是一个挑战。这一挑战的解决方案在于机器学习技术,该技术可以在材料响应与其微观结构描述符之间提供有效的、可微分的映射。这项工作提出了一个框架,通过将基于均质化的拓扑优化策略与基于超弹性理论的一致机器学习方法相结合,设计具有空间变化微观结构的多尺度异质结构。我们利用神经架构,坚持关键的物理原理,如多凸性、客观性、材料对称性和热力学一致性,为框架提供依赖于材料微观结构描述符的可靠本构模型。我们的研究结果强调了将一致机器学习模型与基于密度的拓扑优化相结合的潜力,以增强有限变形下非均质超弹性结构的设计优化。


International Journal of Plasticity

Twinning induced by asymmetric shear response

Jie Huang, Mingyu Lei, Guochun Yang, Bin Wen

doi:10.1016/j.ijplas.2024.104226

不对称剪切反应诱导孪晶

Twinning, a plastic deformation mode, is crucial in dictating material plasticity and significantly impacting their mechanical properties. In this work, we propose a new twinning mechanism based on the phenomenon of asymmetric shear response. By integrating transition state theory with this mechanism, we derive the twinning nucleation stress, and reveal the impact of temperature and strain rate on twin nucleation and growth processes. The model's efficacy is validated through a comparison of predicted results for face centered cubic (FCC), body centered cubic (BCC) and hexagonal close packed (HCP) crystals with experimental ones. This work provides a theoretical foundation for predicting the conditions under which twinning occurs, thereby guiding the design and fabrication of materials containing twin structures.

孪生是一种塑性变形模式,对材料的塑性和力学性能有重要影响。在这项工作中,我们提出了一种新的基于不对称剪切响应现象的孪生机制。将过渡态理论与此机制相结合,导出了孪晶成核应力,揭示了温度和应变速率对孪晶成核和生长过程的影响。通过面心立方(FCC)、体心立方(BCC)和六方密排(HCP)晶体的预测结果与实验结果的比较,验证了该模型的有效性。这项工作为预测孪晶发生的条件提供了理论基础,从而指导含有孪晶结构的材料的设计和制造。


Thin-Walled Structures

Impact resistance and fire resistance of solid waste based interface self-assembled fiber reinforced composite structures

Ke Yan, Shaobo Qi, Xingyu Shen, Mengqi Yuan, Hao Wu, Yunxian Yang, Yazhuo Qian

doi:10.1016/j.tws.2024.112870

固体废物基界面自组装纤维增强复合材料结构的抗冲击和防火性能

Inspired by the resource utilization of solid waste, industrial sludge has been developed as a raw material NH2-MCM-41@Cu-AF. The preparation method of fiber self-assembly structure design was explored by combining macroscopic grafting behavior with the evolution of microscopic bridging structure. The basic mechanical properties, impact resistance, flame retardant, and thermal insulation properties were analyzed. By exploring and predicting the transition from single fiber composite materials to multi-protection, experimental results have shown that NH2-MCM-41@Cu-AF significantly enhances the protective performance. The composite fabric has increased the pulling force by 3.25 times, and the ballistic limit speed has been increased from 57 m/s to 94 m/s. The strong penetration resistance of composite materials has been demonstrated through multi-layer bulletproof performance. Composite fabrics have stronger flame retardancy and thermal insulation, forming a dense protective layer under high temperatures, ensuring structural integrity to the greatest extent possible. Machine learning prediction methods and threshold analysis processes have been established for the final implementation of NH2-MCM-41@Cu-AF. The development of new protective materials and their application in engineering practice provide theoretical support and an experimental basis.

受固体废物资源化利用的启发,工业污泥被开发为原料NH2-MCM-41@Cu-AF。将宏观接枝行为与微观桥接结构演变相结合,探索纤维自组装结构设计的制备方法。分析了材料的基本力学性能、抗冲击性能、阻燃性能和保温性能。通过对单纤维复合材料向多防护过渡的探索和预测,实验结果表明NH2-MCM-41@Cu-AF显著提高了防护性能。复合织物的拉力提高了3.25倍,弹道极限速度从57 m/s提高到94 m/s。复合材料的多层防弹性能证明了复合材料的抗侵彻性能。复合织物具有更强的阻燃性和保温性,在高温下形成致密的保护层,最大限度地保证结构的完整性。机器学习预测方法和阈值分析流程已经建立,最终实现NH2-MCM-41@Cu-AF。新型防护材料的开发及其在工程实践中的应用为工程防护提供了理论支持和实验依据。


Multi-objective optimization of composite stiffened panels for mass and buckling load using PNN-NSGA-III algorithm and TOPSIS method

Tao Zhang, Zhao Wei, Liping Wang, Zhuo Xue, Suian Wang, Peiyan Wang, Bowen Qi, Zhufeng Yue

doi:10.1016/j.tws.2024.112878

基于PNN-NSGA-III算法和TOPSIS方法的复合材料加筋板质量和屈曲载荷多目标优化

A novel multi-objective optimization framework for composite stiffened panels is proposed in this study, leveraging a combination of the Parallel Neural Network (PNN), Non-dominated Sorting Genetic Algorithm-III (NSGA-III), and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. This framework demonstrates high efficiency and accuracy in obtaining the optimal design for intricate optimization challenges. The PNN in this framework, leveraging data-driven methods, addresses the limitations of Classical Laminate Theory (CLT) in constructing optimization surrogate models, such as challenges in parameter range determination, lack of independence, and the necessity for secondary inverse problem solving. In contrast to NSGA-II, NSGA-III which uses reference points and correlation operators achieves more uniform and rich Pareto fronts under stacking sequence constraints. Additionally, to minimize the required effort and expert knowledge in selecting optimal design parameters, this framework incorporates the Entropy Weight Method (EWM) and TOPSIS method. EWM calculates the entropy of optimization objectives from all alternatives in the Pareto front, assigns weights accordingly, and employs TOPSIS to rank the closeness of each alternative to the ideal solution, thereby identifying the optimal design.

基于并行神经网络(PNN)、非支配排序遗传算法- iii (NSGA-III)和TOPSIS方法,提出了一种新的复合材料加筋板多目标优化框架。该框架在复杂的优化问题中具有较高的效率和准确性。该框架中的PNN利用数据驱动方法,解决了经典层压板理论(CLT)在构建优化代理模型方面的局限性,例如参数范围确定方面的挑战、缺乏独立性以及二次逆问题求解的必要性。与NSGA-II相比,使用参考点和相关算子的NSGA-III在叠加序列约束下实现了更均匀、更丰富的Pareto front。此外,为了最大限度地减少选择最优设计参数所需的努力和专家知识,该框架结合了熵权法(EWM)和TOPSIS方法。EWM从Pareto front的所有备选方案中计算优化目标的熵,分配相应的权重,并利用TOPSIS对每个备选方案与理想解的接近程度进行排序,从而确定最优设计。

来源:复合材料力学仿真Composites FEM
ACTMechanicalAdditiveInspireDeform复合材料非线性拓扑优化增材理论材料多尺度控制
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首次发布时间:2025-01-11
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【新文速递】2025年1月2日固体力学SCI期刊最新文章

今日更新:International Journal of Solids and Structures 1 篇,International Journal of Plasticity 4 篇,Thin-Walled Structures 6 篇International Journal of Solids and StructuresNon-local orthotropic damage-plastic model for 3D printed materialsDenis Linardi, Elisabetta Monaldo, Sonia Marfiadoi:10.1016/j.ijsolstr.2024.1132103D打印材料的非局部正交各向异性损伤塑性模型A non-local orthotropic damage and plasticity phenomenological model for 3D printed materials is presented. The model specifically refers to 3D printed structural elements realized with an extrusion-based technique and made with thermoplastic materials. The structural behaviour of the 3D printed component is described with a laminate finite element model based on the first-order shear deformation theory. Each layer of the laminate is described with a non-local orthotropic damage and plastic model. Indeed, the overall mechanical response of 3D printed materials is significantly influenced by plasticity and damage mechanisms that can lead to a range of failure modes from brittle-like to ductile. The proposed orthotropic damage model is based on the introduction of three different damage parameters. Each of them describes a specific damage mechanism, i.e. fiber breakage, fiber detachment and delamination, that is clearly visible from the analysis of the 3D printed samples subjected to experimental tests. Some applications are carried out and the numerical results are compared with experimental results available in literature, highlighting the effectiveness of the proposed modelling technique.提出了3D打印材料的非局部正交各向异性损伤和塑性现象学模型。该模型具体指的是采用基于挤出技术并由热塑性材料制成的3D打印结构元件。 采用基于一阶剪切变形理论的层合有限元模型描述了3D打印部件的结构行为。用非局部正交各向异性损伤和塑性模型描述了层合板的每一层。事实上,3D打印材料的整体力学响应受到塑性和损伤机制的显著影响,这可能导致从脆性到延性的一系列失效模式。提出的正交各向异性损伤模型是在引入三种不同损伤参数的基础上建立的。每一种都描述了一种特定的损伤机制,即纤维断裂、纤维脱离和分层,这从经过实验测试的3D打印样品的分析中可以清楚地看到。将数值结果与文献中的实验结果进行了比较,强调了所提出的建模技术的有效性。International Journal of PlasticityMultiscale modeling of the damage and fracture behaviours of TA15 titanium alloy with trimodal microstructureM.Y. Fei, P.F. Gao, Z.N. Lei, H.W. Li, M. Zhan, M.W. Fudoi:10.1016/j.ijplas.2024.104238 TA15钛合金三模态组织损伤断裂行为的多尺度模拟Trimodal microstructure, consisting of equiaxed α (αp), lamellar α (αl), and transformed β (βt), has become an ideal target microstructure of titanium alloys. However, the complex microstructure morphologies and the differences in mechanical property among the three constituent phases of the trimodal microstructure significantly influence its microscopic crack propagation behaviour and further affect its fracture toughness. To address this issue, a multiscale finite element (FE) model, including a microscopic crack propagation (micro-CP) model and a macroscopic fracture toughness (macro-FT) model, was established for analysis and prediction of the damage fracture behaviour and property of the trimodal microstructure. In this model, the deformation, damage and fracture behaviours of the trimodal microstructure at both micro and macro scales were described by bridging the constitutive laws of constituent phases and deformation responses. In tandem with this, the micro-CP model adopted a macro-micro nested structure, and the macro-FT model was developed based on a virtual fracture toughness test. Using the established multiscale FE model, the dependence of microscopic crack propagation and macroscopic fracture behaviours on the constituent phases of the trimodal microstructure was revealed. It is found that both αp and αl improved the path tortuosity and energy consumption of microscopic crack propagation, and αl decreased the microscopic crack propagation rate simultaneously. In addition, αp and αl contributed to the fracture toughness of the trimodal microstructure from both the intrinsic toughening mechanism (suppressing the heterogeneous deformation and damage and then decreasing the strength and increasing the plasticity) and the extrinsic toughening mechanism (increasing the tortuosity and energy consumption of crack propagation). The research provided an in-depth understanding of the damage and fracture behaviours of TA15 titanium alloy with the trimodal microstructure.由等轴α(αp)、层片α(αl)和转变β(βt)组成的三相微结构已成为钛合金的理想目标微结构。然而,这种复杂微结构的形态以及三相成分之间机械性能的差异显著影响其微观裂纹扩展行为,并进一步影响其断裂韧性。为解决这一问题,建立了包含微观裂纹扩展(micro-CP)模型和宏观断裂韧性(macro-FT)模型的多尺度有限元(FE)模型,用于分析和预测三相微结构的损伤断裂行为和性能。在该模型中,通过连接各组成相的本构定律和变形响应,描述了三相微结构在微观和宏观尺度上的变形、损伤和断裂行为。同时,micro-CP 模型采用了宏观-微观嵌套结构,而 macro-FT 模型则是基于虚拟断裂韧性测试开发的。利用已建立的多尺度有限元模型,揭示了三相微结构的组成相对于微观裂纹扩展和宏观断裂行为的影响。研究发现,αp 和 αl 均提高了微观裂纹扩展的路径曲折度和能量消耗,同时 αl 还降低了微观裂纹扩展速率。此外,αp 和 αl 从内在增韧机制(抑制异质变形和损伤,从而降低强度并提高塑性)和外在增韧机制(增加裂纹扩展的曲折度和能量消耗)两方面提高了三相微结构的断裂韧性。该研究为具有三相微结构的 TA15 钛合金的损伤和断裂行为提供了深入的理解。A thermodynamically consistent phase-field model for frictional fracture in rocksSijia Liu, Yunteng Wangdoi:10.1016/j.ijplas.2024.104220岩石摩擦断裂的热力学一致相场模型Frictional fracture phenomena in geological media are often closely related to fault instability in earthquakes and slip surface formation in geohazards. In this work, we propose a new phase-field model for capturing frictional fractures in pressure-sensitive geomaterials. Our model has three novel features: (i) a thermodynamically consistent energetic interface for contact and friction conditions; (ii) incorporation of a level set function to couple phase-field evolution and frictional-contact slips; and (iii) a transition from stored energy to yielding for describing different plastic-like frictional stick–slip fractures. Based on the energy conservation law and a variational inequality of virtual work, we formulate the governing equations for frictional fractures, including the dynamic equilibrium equation, phase-field evolution law, and most importantly, frictional interface plastic-like driving forces. We also present a robust numerical technique to handle the spatiotemporal formation and evolution of frictional fractures in rocks. We validate the model by simulating several benchmark examples. Our model is shown to reproduce both frictional stick and slip phenomena in rocks. We also apply this model to study the effect of confining pressure on frictional crack initiation and propagation in rocks, which helps us better understand the deep mechanisms of frictional fracture.地质介质中的摩擦断裂现象往往与地震中的断层失稳和地质灾害中的滑面形成密切相关。在这项工作中,我们提出了一种新的相场模型,用于捕获压力敏感岩土材料中的摩擦裂缝。我们的模型具有三个新特征:(i)接触和摩擦条件下的热力学一致的能量界面;(ii)结合一个水平集函数来耦合相场演化和摩擦接触滑移;(3)从存储能量到屈服的过渡,用于描述不同的类塑性粘滑摩擦裂缝。基于能量守恒定律和虚功的变分不等式,建立了摩擦断裂的控制方程,包括动力学平衡方程、相场演化定律,以及最重要的摩擦界面类塑性驱动力。我们还提出了一种强大的数值技术来处理岩石中摩擦裂缝的时空形成和演化。我们通过模拟几个基准示例来验证模型。我们的模型被证明可以再现岩石中的摩擦粘和滑动现象。我们还应用该模型研究了围压对岩石摩擦裂纹萌生和扩展的影响,这有助于我们更好地理解摩擦破裂的深层机制。Advancing material simulations: Physics-Informed Neural Networks and Object-Oriented Crystal Plasticity Finite Element MethodsShahriyar Keshavarz, Yuwei Mao, Andrew C.E. Reid, Ankit Agrawaldoi:10.1016/j.ijplas.2024.104221 先进的材料模拟:物理信息神经网络和面向对象的晶体塑性有限元方法An innovative method for predicting the behavior of crystalline materials is presented by integrating Physics-Informed Neural Networks (PINNs) with an object-oriented Crystal Plasticity Finite Element (CPFE) code within a large deformation framework. The CPFE platform is utilized to generate reference data for training the PINNs, ensuring precise and fast predictions of material responses. The object-oriented design of the CPFE system facilitates the coherent incorporation of complex constitutive models and numerical methods, enhancing simulation flexibility and scalability. To demonstrate the adaptability of this approach, two problems are addressed: a fundamental power-law and a complex dislocation density-based constitutive models for predicting the behavior of Ni3Al-based alloys. Both models are implemented within an object-oriented CPFE system powered by its flexible plug-in architecture. The resulting PINN model accurately captures intricate deformation mechanisms in crystalline materials, as validated through comparisons with CPFE simulations and experimental data. This work offers a promising alternative for efficient and accurate material behavior prediction, paving the way for advanced simulations in materials science.本文提出了一种创新方法,通过将物理信息神经网络(PINNs)与面向对象的晶体塑性有限元(CPFE)代码集成在一个大变形框架内,来预测晶体材料的行为。CPFE 平台用于生成训练 PINNs 的参考数据,从而确保对材料响应进行精确且快速的预测。CPFE 系统的面向对象设计有助于将复杂的本构模型和数值方法进行一致整合,从而提高模拟的灵活性和可扩展性。为了展示该方法的适应性,解决了两个问题:一个是基本的幂律模型,另一个是基于位错密度的复杂本构模型,用于预测 Ni3Al 基合金的行为。这两个模型均在由其灵活的插件架构支持的面向对象 CPFE 系统中实现。通过与 CPFE 模拟和实验数据的比较验证,所得的 PINN 模型能够准确捕捉晶体材料中复杂的变形机制。这项工作为高效且准确地预测材料性能提供了一种很有前景的替代方案,为材料科学中的高级模拟铺平了道路。Modeling inter- and intra-granular dislocation transport using crystal plasticitySubhendu Chakraborty, Abigail Hunter, D.J. Luscherdoi:10.1016/j.ijplas.2024.104222 利用晶体塑性模拟晶间和晶内位错输运This work presents the development of a crystal plasticity material model that incorporates both dislocation transport within grains and dislocation transfer across grain boundaries. This model has been implemented in the open-source finite element code MOOSE. In addition, a novel geometry-based criterion is developed to determine the direction of dislocation transfer across grain boundaries. The transfer criterion incorporates the geometric features of the grain boundary, such as the grain boundary plane normal, and its misorientation, which is accounted for through the orientation of the incoming and outgoing slip systems. The model is tested with several cases, including a copper single crystal, bi-crystal, and polycrystal. The development of the transfer criterion, implementation of the model, and its application to these test cases are discussed in detail.这项工作提出了晶体塑性材料模型的发展,该模型结合了晶粒内的位错传递和跨晶界的位错传递。该模型已在开源有限元代码MOOSE中实现。此外,提出了一种新的基于几何的判据来确定位错跨晶界转移的方向。传递准则结合了晶界的几何特征,如晶界平面法向及其取向偏差,这是通过进出滑动系统的取向来解释的。该模型在几种情况下进行了测试,包括铜单晶,双晶和多晶。详细讨论了转移准则的开发、模型的实现及其在这些测试用例中的应用。Thin-Walled StructuresNovel resonator concept for improved performance of locally resonant based metamaterialsF.A. Pires, R.F. Boukadia, M. Wandel, C. Thomas, E. Deckers, W. Desmet, C. Claeysdoi:10.1016/j.tws.2024.112866改进局部共振基超材料性能的新谐振器概念In the context of noise control engineering, locally resonant metamaterials (LRMs) have gained significant research attention over the past two decades due to their ability to combine lightweight, compact design with excellent noise and vibration insulation performance in targeted frequency ranges, known as stop bands. This paper proposes a novel resonator concept that achieves a high modal effective mass (MEF) for out-of-plane bending, aiming to widen the stop bands in LRMs. First, the dynamic motion of an idealized double-lever system, which inspired the resonator design, is analyzed. Then, a realizable resonator design is presented, along with an optimization scheme that maximizes the MEF, achieving values as high as 96.5%. The proposed resonator concept is used to develop an LRM solution to enhance the acoustic insulation performance of a structure relevant to the aerospace industry, yielding improvements of up to 9 dB in the frequency band of interest. Experimental results demonstrate that the designed LRM solution significantly improves the vibro-acoustic response of the system. Future work will consider additional aspects of the optimization process, including manufacturing constraints, costs, and robustness.在噪声控制工程的背景下,局部谐振超材料(lrm)在过去的二十年中获得了重要的研究关注,因为它们能够将轻质,紧凑的设计与在目标频率范围内(称为阻挡带)的优异噪声和振动绝缘性能相结合。本文提出了一种新的谐振器概念,实现了高模态有效质量(MEF)的面外弯曲,旨在扩大lrm中的阻带。首先,分析了理想双杠杆系统的动态运动,该系统启发了谐振器的设计。然后,提出了一个可实现的谐振器设计,以及一个最大化MEF的优化方案,使MEF达到高达96.5%的值。提出的谐振器概念用于开发LRM解决方案,以增强与航空航天工业相关的结构的隔音性能,在感兴趣的频带内产生高达9 dB的改进。实验结果表明,所设计的LRM方案显著改善了系统的声振响应。未来的工作将考虑优化过程的其他方面,包括制造限制、成本和鲁棒性。Torsional Restraint of Roof Sheeting on Cold-Formed Steel Hat SectionsJohn Papangelis, Chong Li, Liao Yi, Fangyuan Yuedoi:10.1016/j.tws.2024.112882冷弯型钢顶板的抗扭约束Cold-formed steel hat sections are commonly used as thin-walled beams to support thin profiled roof sheeting. Cold-formed steel sections are usually thinner than hot-rolled sections and have modes of failure which are not commonly encountered in hot-rolled structural steel design. The individual plate elements in cold-formed steel hat sections are normally thin compared with their width and so local and distortional buckling may occur before section yielding. In addition, cold-formed steel hat sections may undergo flexural-torsional buckling because of their low torsional stiffness. For cold-formed steel hat sections which may fail by flexural-torsional buckling, the roof sheeting provides a torsional restraint which can increase the flexural-torsional buckling capacity. Previous research has focused on determining the torsional restraint provided by roof sheeting to C and Z section purlins but no research has been done for hat sections. This paper describes a unique test procedure to determine the value of the torsional restraint provided by roof sheeting on hat sections for 12 different combinations of hat sections and roof sheeting profiles. Three tests for each combination were performed, resulting in a total of 36 tests. The results show that the torsional restraint increases as the depth or thickness of the hat section is increased and also when the sheeting thickness increases. A finite element flexural-torsional buckling analysis is also described for analysing hat sections with elastic continuous restraints, such as those provided by roof sheeting. The finite element analysis is validated with the theoretical solution for the flexural-torsional buckling of hat sections with torsional restraint and diaphragm shear restraint. An example is described to demonstrate the effect of torsional restraint and diaphragm shear restraint on the flexural-torsional buckling of hat sections subjected to uniformly distributed load. It is shown that including these restraints in the analysis will result in a significant increase in the flexural-torsional buckling load and the design load capacity.冷弯型钢帽截面通常用作薄壁梁来支撑薄型屋面板。冷弯型钢通常比热轧型钢更薄,并且具有热轧型钢设计中不常见的失效模式。冷弯型钢帽截面中的单个板单元通常比其宽度薄,因此在截面屈服之前可能发生局部扭曲屈曲。此外,冷弯型钢帽截面由于其扭转刚度低,可能发生弯扭屈曲。对于可能受弯扭屈曲破坏的冷弯型钢帽型钢,顶板提供了扭转约束,可以增加弯扭屈曲能力。以往的研究主要集中在确定顶板对C、Z截面檩条的抗扭约束上,但对C、Z截面檩条的抗扭约束尚未进行研究。本文描述了一种独特的测试程序,用于确定12种不同的帽型和车顶板型的组合,车顶板对帽型提供的扭转约束值。对每种组合进行了三次测试,总共进行了36次测试。结果表明,扭转约束随帽段深度或厚度的增加而增大,随板层厚度的增加而增大。有限元弯扭屈曲分析也描述了分析具有弹性连续约束的帽段,例如由屋面板提供的那些。通过有限元分析验证了具有扭转约束和膜片剪切约束的帽形截面弯曲-扭转屈曲的理论解。通过算例验证了扭转约束和膜片剪切约束对均布荷载作用下帽形截面弯扭屈曲的影响。结果表明,在分析中加入这些约束将导致弯扭屈曲载荷和设计载荷能力的显著增加。Nonlinear Vibration-acoustic Analysis of the Coupled System of Flexible Cylindrical Shell Foundation and HSLDS Vibration IsolatorJunfeng Liu, Jingjun Lou, Kai Chai, Qingchao Yangdoi:10.1016/j.tws.2024.112896柔性圆柱壳基础与HSLDS隔振器耦合系统的非线性振动-声分析This paper is concerned with the vibration and acoustic radiation problems of the coupled system of mass oscillator, high-static-low-dynamic stiffness (HSLDS) isolator and flexible stiffened cylindrical shell immersed in an infinite acoustic medium. A frequency domain numerical calculation method is proposed. The HSLDS isolator is fitted by odd-order polynomials, and the periodic solution of the deformation of the HSLDS isolator spring is expanded into a superimposed harmonic function. The dynamic stiffness matrix of the stiffened cylindrical shell is established by the wave propagation method, and the force of the external acoustic fluid on the shell is introduced by the Helmholtz boundary integral equation, and the acoustic radiation calculation is carried out. Based on the force and displacement continuity conditions and the interface compatibility conditions between the structure and the acoustic medium, the dynamic stiffness matrix of the mass-spring-damper system, the stiffened cylindrical shell and the external fluid coupling is established, and the harmonic balance method and Newton-like solver are used to solve it. By comparing the solutions of the finite element method and the boundary element method, the accuracy of the method is verified, and the predicted results are in good agreement with the reference results. The effects of circumferential wave modes and the number of axially discrete 3-node elements of cylindrical shells on the vibration and radiated acoustic response of nonlinear coupling systems are studied. The effects of HSLDS isolators, damping and the amplitude of external loads on the vibration and acoustic radiation behavior of the coupling system are studied, and the influences of HSLD isolators on shell vibration and acoustic radiation propagation are analyzed, which can provide useful guidance for the vibration isolation design and optimization of underwater rigid-flexible coupling systems.研究了质量振子、高静低动刚度(HSLDS)隔振器和柔性加筋圆柱壳在无限大声介质中的耦合系统的振动和声辐射问题。提出了一种频域数值计算方法。采用奇阶多项式对HSLDS隔振器进行拟合,将HSLDS隔振器弹簧变形的周期解展开为叠加谐波函数。采用波传播法建立加劲圆柱壳的动力刚度矩阵,采用亥姆霍兹边界积分方程引入外声流体对壳体的作用力,并进行声辐射计算。基于力和位移连续条件和结构与声介质界面相容条件,建立了质量-弹簧-阻尼器系统、加劲圆柱壳和外部流体耦合的动态刚度矩阵,并采用谐波平衡法和类牛顿求解器对其进行求解。通过比较有限元法和边界元法的解,验证了该方法的准确性,预测结果与参考结果吻合较好。研究了圆柱壳的周向波模态和轴向离散3节点单元数对非线性耦合系统振动和辐射声响应的影响。研究了HSLD隔振器、阻尼和外载荷幅值对耦合系统振动和声辐射特性的影响,分析了HSLD隔振器对壳体振动和声辐射传播的影响,为水下刚柔耦合系统的隔振设计和优化提供了有益的指导。Impact properties and damage assessment of unidirectional aramid/carbon fiber hybrid reinforced polymer compositesXiaogang Liu, Weichen Kong, Siqi Song, Anni Wangdoi:10.1016/j.tws.2024.112898单向芳纶/碳纤维杂化增强聚合物复合材料的冲击性能及损伤评估To improve the impact resistance of unidirectional carbon fiber-reinforced polymer (CFRP) composites, unidirectional aramid/carbon fiber hybrid-reinforced polymer (A/CFHRP) composites were developed. Through a series of low-speed impact tests, ultrasonic scanning, CT scanning, and post-impact compression tests, the study examined the impact response, damage modes, and severity of damage in A/CFHRP composites with varying fiber volume ratios. Additionally, the residual properties after impact were assessed. The findings revealed that the incorporation of aramid fibers significantly enhances the impact resistance of CFRP. As the aramid fiber content increased, the specific energy absorption of A/CFHRP initially increased and then decreased, indicating an upper limit to the improvement in impact resistance provided by aramid, which is dependent on the impact energy. The maximum specific energy absorption of A/CFHRP is 46% higher than that of CFRP. The introduction of aramid fibers transforms the damage mode of CFRP from brittle fracture to interlayer delamination and interface debonding, thereby preserving higher structural integrity and superior post-impact residual performance. After 10J impact energy, the strength retention rate of A/CFRP after impact is 81.2% higher than that of CFRP; after 50J impact energy, the strength retention rate of A/CFRP after impact is 37.4% higher than that of CFRP为了提高单向碳纤维增强聚合物(CFRP)复合材料的抗冲击性能,研制了单向芳纶/碳纤维混合增强聚合物(A/CFHRP)复合材料。通过一系列低速冲击试验、超声扫描、CT扫描和冲击后压缩试验,研究了不同纤维体积比下a /CFHRP复合材料的冲击响应、损伤模式和损伤严重程度。此外,还对冲击后的残余性能进行了评估。结果表明,芳纶纤维的掺入显著提高了CFRP的抗冲击性。随着芳纶纤维含量的增加,A/CFHRP的比能量吸收率先升高后降低,说明芳纶提高抗冲击性能的能力有一个上限,这取决于冲击能量。A/CFHRP的最大比能量吸收比CFRP高46%。芳纶纤维的引入使CFRP的损伤模式从脆性断裂转变为层间分层和界面脱粘,从而保持了较高的结构完整性和优异的冲击后残留性能。10J冲击能量后,A/CFRP的强度保持率比CFRP高81.2%;50J冲击能量后,A/CFRP的强度保持率比CFRP高37.4%Material performance, manufacturing methods, and engineering applications in aviation of Carbon fiber reinforced polymers: A comprehensive reviewXiangyu Xu, Gongqiu Peng, Baoyan Zhang, Fenghui Shi, Liang Gao, Junpeng Gaodoi:10.1016/j.tws.2024.112899碳纤维增强聚合物材料性能、制造方法及其在航空工程中的应用综述Carbon fiber reinforced polymers (CFRP) is becoming the predominant material in the aviation industry due to its excellent performance including light weight, high specific strength, high specific modulus, excellent fatigue fracture resistance, corrosion resistance, strong design flexibility, and suitability for the overall molding of large components. The application parts of CFRP are almost all over the aircrafts, such as wings, tails, fuselages, landing gears, engines and other parts. The proportion of fiber reinforced polymer matrix composites (PMCs) has become an essential indicator of aircrafts in practical engineering applications. This paper provides an overview of the background and evolution of CFRPs followed by an introduction to the material properties of carbon fibers (CFs) and different resin matrices. Subsequently, the principle and characteristics of the commonly used manufacturing methods of CFRP are presented. Next, the material performance of both thermosetting and thermoplastic CFRP are provided. Finally, the applications in aviation and the developing trends of CFRP are described. This review aims to offer researchers a comprehensive reference on the material performance and applications of CFRP within the aviation field while providing valuable insights for future PMC advancements.碳纤维增强聚合物(CFRP)具有重量轻、比强度高、比模量高、抗疲劳断裂、耐腐蚀、设计柔韧性强、适合大型部件整体成型等优点,正成为航空工业的主导材料。CFRP的应用部件几乎遍及飞机的各个部位,如机翼、尾翼、机身、起落架、发动机等部件。在实际工程应用中,纤维增强聚合物基复合材料(PMCs)的比例已成为飞机性能的重要指标。本文概述了碳纤维纤维的背景和发展,然后介绍了碳纤维(CFs)和不同树脂基体的材料特性。随后,介绍了碳纤维增强塑料的常用制造方法的原理和特点。其次,介绍了热固性和热塑性CFRP的材料性能。最后介绍了碳纤维布在航空领域的应用及发展趋势。本综述旨在为研究人员提供碳纤维增强塑料在航空领域的材料性能和应用的综合参考,同时为未来碳纤维增强塑料的发展提供有价值的见解。From the Yoshimura origami pattern to foldable structures: Exploration of crease designZhitong Fei, Dongyang Xu, Yanzhi Zhao, Zhen Han, Linquan Song, Ruibao Ma, Yulin Guodoi:10.1016/j.tws.2024.112888从吉村折纸图案到可折叠结构:折痕设计的探索Crease design is crucial to the function and application scope of origami projects; however, for the Yoshimura origami pattern, the connection between origami two-dimensional (2D) creases and three-dimensional (3D) forms has not been established, which greatly limits the research and application of origami structures. In this paper, a crease design theory for the Yoshimura origami pattern is proposed to create 3D foldable origami structures. Afterward, the flat origami folding process is described, and the corresponding end trajectory equations are derived from a crease chain folding analysis performed on the element block and the expansion block. Next, the positional and angular constraint equations for single-variable, double-variable, and triple-variable foldable forms with only element blocks are systematically discussed. Finally, a detailed folding simulation analysis is performed based on the positional and angular constraint equations, and the foldable form family diagrams with the corresponding angular value intersection curve constraints are summarized. The theory is verified by finite element programs and experiments. This work provides an effective theory for the design of origami creases and new ideas and methods for the study of the Yoshimura pattern and other origami patterns.折痕设计对折纸项目的功能和应用范围至关重要;然而,对于吉村折纸图案,折纸二维(2D)折痕与三维(3D)折痕之间的联系尚未建立,这极大地限制了折纸结构的研究和应用。本文提出了一种吉村折纸图案的折痕设计理论,用于创建三维可折叠折纸结构。然后,描述了平面折纸的折叠过程,并通过对单元块和膨胀块进行折痕链折叠分析,推导了相应的末端轨迹方程。其次,系统地讨论了单变量、双变量和三变量仅包含单元块的可折叠形式的位置和角度约束方程。最后,基于位置约束方程和角度约束方程进行了详细的折叠仿真分析,总结了具有相应角值相交曲线约束的可折叠形式族图。通过有限元程序和实验对理论进行了验证。本工作为折纸折痕的设计提供了有效的理论依据,也为吉村图案等折纸图案的研究提供了新的思路和方法。来源:复合材料力学仿真Composites FEM

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