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Towards the exploration of self-starting single-solve integration algorithms with third-order accuracy for nonlinear dynamics 非线性动力学三阶精度自启动单解积分算法的探索
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-19 DOI: 10.1016/j.euromechsol.2025.105954
Yaokun Liu, Jinze Li, Kaiping Yu
The single-step explicit time integration methods have long been valuable for solving large-scale nonlinear dynamic problems, classified into single-solve and multi-sub-step approaches. However, no existing conventional single-solve methods achieve third-order accuracy in any primary variables (displacement, velocity or acceleration). The paper addresses this gap by the framework of conventional self-starting single-solve time integration algorithms, which incorporates eleven algorithmic parameters. The study reveals that self-starting single-solve explicit methods cannot reach third-order accuracy in any primary variables for solving damped problems. Consequently, two novel algorithms are proposed: Algorithm 1 is an explicit scheme that achieves third-order accuracy in displacement and velocity undamped problems; Algorithm 2 is an implicit scheme which degenerates to an explicit scheme when solving the undamped problems, and it achieves third-order accuracy in displacement and velocity for any damped problems. Across a suite of both linear and nonlinear benchmarks, the new algorithms consistently outperform existing conventional explicit methods in accuracy. Their built-in numerical dissipation effectively filters out spurious high-frequency components, as demonstrated by two wave propagation problems. Finally, when applied to the realistic engineering problem, both of them deliver superior numerical precision at a reasonable computational cost.
单步显式时间积分法在求解大规模非线性动力问题方面一直具有重要的应用价值,可分为单步法和多子步法。然而,现有的常规单次求解方法在任何主要变量(位移、速度或加速度)上都无法达到三阶精度。本文通过传统的自启动单解时间积分算法框架解决了这一缺陷,该算法包含11个算法参数。研究表明,自启动单解显式方法在求解阻尼问题时,在任何主变量上都不能达到三阶精度。因此,提出了两种新的算法:算法1是一种显式格式,在位移和速度无阻尼问题中达到三阶精度;算法2是一种隐式格式,在求解无阻尼问题时退化为显式格式,对于任何有阻尼问题,它在位移和速度上都能达到三阶精度。在一系列线性和非线性基准测试中,新算法在精度上始终优于现有的传统显式方法。其内置的数值耗散有效地滤除了杂散高频分量,正如两个波传播问题所证明的那样。最后,当应用于实际工程问题时,两者都以合理的计算成本提供了较高的数值精度。
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引用次数: 0
3D star-shaped lattice metamaterials exhibiting zero Poisson's ratio 零泊松比的三维星形晶格超材料
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-19 DOI: 10.1016/j.euromechsol.2025.105952
Luke Mizzi, Alexandre Périer
Zero Poisson's ratio metamaterials are a peculiar class of metamaterial systems which undergo no lateral deformation upon uniaxial loading. In this work, we propose a new 3D star-shaped lattice metamaterial structure which is specifically designed to exhibit this property in all three principal directions. This system, which is highly anisotropic, can have a tailorable stiffness which is dependent on the geometry of the structure and may be altered according to design specifications without influencing the Poisson's ratio. An analytical model which may be used to predict the mechanical properties of this system was derived and validated through a wide ranging parametric Finite Element simulation run. In addition, a prototype system was produced using additive manufacturing and tested under compressive loading, with Digital Image Correlation techniques confirming the zero Poisson's ratio of the system, which is retained under relatively high-strain loading. It is envisaged that the large versatility and tuneability of this new metamaterial structure make it ideal for future implementation in applications requiring zero Poisson's ratio properties.
零泊松比超材料是一类特殊的在单轴载荷作用下不发生侧向变形的超材料体系。在这项工作中,我们提出了一种新的3D星形晶格超材料结构,该结构专门设计用于在所有三个主要方向上表现出这种特性。该系统具有高度的各向异性,可以根据结构的几何形状定制刚度,并且可以根据设计规范进行更改,而不会影响泊松比。推导了可用于预测该系统力学性能的解析模型,并通过大范围参数有限元仿真运行进行了验证。此外,使用增材制造技术制作了一个原型系统,并在压缩载荷下进行了测试,使用数字图像相关技术确认了系统的零泊松比,该泊松比在相对高应变载荷下保持不变。据设想,这种新的超材料结构的大通用性和可调性使其成为未来在需要零泊松比特性的应用中实现的理想选择。
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引用次数: 0
Unified model of rub-impact vibration response of high-low pressure double-rotor-SFD-intermediate bearing system of aero-engine under typical maneuvering loads 典型机动载荷下航空发动机高低压双转子- sfd -中间轴承系统碰摩振动响应统一模型
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-19 DOI: 10.1016/j.euromechsol.2025.105948
Wujiu Pan , Yuting Liu , Qilong Wu , Wenxin Wang , Junyi Wang
Dual-rotor aero-engines are widely used in the field of aero-engines, with their outer and inner rotors coupled via an intermediate bearing. The coupling characteristics introduced by the intermediate bearing increase the complexity of the system's dynamic properties, making it necessary to analyze the different nonlinear dynamic behaviors of the dual-rotor system under typical maneuvering conditions. Based on finite element theory, a model of a 10-node diameter shaft double rotor system with SFD-intermediate bearings was established under three typical maneuvering conditions. The model includes the oil film force, the nonlinear Hertzian contact force, the blade-casing rub-impact force, the gravitational field, the rotor eccentric imbalance force, and typical maneuvering loads. The correctness of the present theoretical modeling method was verified by comparing it with the ANSYS modeling method. The Newmark-β method was used to solve the 10-node-diameter shaft model. The system's blade-casing rub-impact response under different maneuvering loads and different rotor speed ratios was analyzed, and the system response characteristics under three maneuvering flight conditions were compared and analyzed. Research has found that under the same dynamic load or speed ratio conditions, the possibility of blade-casing rub-impact between dual rotor systems under different dynamic conditions varies.
双转子航空发动机是一种广泛应用于航空发动机领域的发动机,其内外转子通过中间轴承耦合。中间轴承引入的耦合特性增加了系统动态特性的复杂性,因此有必要对典型机动工况下双转子系统的不同非线性动态行为进行分析。基于有限元理论,建立了含sfd -中间轴承的10节直径轴双转子系统在三种典型机动工况下的模型。该模型包括油膜力、非线性赫兹接触力、叶片-机匣摩擦-撞击力、引力场、转子偏心不平衡力和典型机动载荷。通过与ANSYS建模方法的比较,验证了该理论建模方法的正确性。采用Newmark-β方法求解10节径轴模型。分析了系统在不同机动载荷和不同旋翼速比下的叶片-机匣摩碰响应,对比分析了系统在三种机动飞行工况下的响应特性。研究发现,在相同动载荷或速比条件下,不同动态条件下双转子系统发生叶片-机匣碰摩的可能性是不同的。
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引用次数: 0
Modified method for deriving the receptance function of a cracked nonuniform AFG beam carrying concentrated masses and its application for crack detection 承载集中质量的裂纹非均匀AFG梁接收函数的修正推导方法及其在裂纹检测中的应用
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-13 DOI: 10.1016/j.euromechsol.2025.105947
Khoa Viet Nguyen , Thao Thi Bich Dao
This paper presents a simplified Adomian method for establishing the exact receptance function of a cracked nonuniform axially functionally graded (AFG) beam carrying concentrated masses. In previous studies, the receptance functions of a beam with varying ratios of properties along the length of beam have been derived in the form of power series by using Adomian method. However, this method often requires applying the Cauchy products of infinite series, which is time consuming. The more properties of the beam, such as elastic modulus, mass density, height, or width, vary along its length, the more Cauchy products of infinite series must be computed. This study introduces a new technique to avoid calculating Cauchy products. Moreover, the proposed method requires calculating only second-order determinant for beam with an arbitrary number of cracks, resulting in further reduction of computational time compared to previous methods, which require calculating determinants of much higher order. The proposed method always provides the explicit solution for the receptance function when the elastic modulus E and moment of inertia I are expressed as polynomials of arbitrary degree. When there are cracks, the receptance function is distorted locally at crack positions. The influence of the concentrated masses on these distortions in the receptance function is investigated. Numerical simulations show that concentrated masses located at suitable positions can significantly amplify the effects of the cracks on the receptance function, which may be useful for crack detection.
本文提出了一种简化的Adomian方法,用于建立带集中质量的裂纹非均匀轴向功能梯度(AFG)梁的精确接收函数。在以往的研究中,采用Adomian方法推导出沿梁长方向具有不同性质比的梁的接收函数,其形式为幂级数形式。然而,这种方法往往需要应用无穷级数的柯西积,耗时较长。梁的特性,如弹性模量、质量密度、高度或宽度,沿其长度变化越多,必须计算的无穷级数的柯西积就越多。本文介绍了一种避免计算柯西积的新方法。此外,该方法只需要计算具有任意数量裂缝的梁的二阶行列式,与之前需要计算高阶行列式的方法相比,进一步减少了计算时间。当弹性模量E和转动惯量I表示为任意次多项式时,所提出的方法总能给出接收函数的显式解。当存在裂纹时,接收函数在裂纹位置局部变形。研究了集中质量对接收函数畸变的影响。数值模拟结果表明,适当位置的集中质量可以显著放大裂纹对接收函数的影响,这可能有助于裂纹检测。
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引用次数: 0
Strain-dependent model for studying the cyclic flexural behavior of GLARE 研究眩光循环弯曲性能的应变依赖模型
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-13 DOI: 10.1016/j.euromechsol.2025.105950
Alborz Mohebi , Gholamhossein Majzoobi , Mohammad Kashfi , Kaveh Rahmani
Fiber Metal Laminates, especially GLARE (Glass Laminates Aluminum Reinforced Epoxy), are widely used in aerospace and automotive applications due to their lightweight, high specific strength, and superior fatigue resistance. In this work, the cyclic flexural behavior of GLARE is studied for the strain ranges of 1.13 %, 1.75 %, and 2.32 % to assess its fatigue performance and degradation under cyclic loading. Cyclic three-point bending tests were performed on the GLARE composed of Al 2024-T3 and E-glass fiber-reinforced epoxy layers with 67 % metal volume fraction. In the low strain range (1.13 %), GLARE displayed elastic behavior with minimal plastic deformation and energy dissipation. On the other hand, for the higher strain ranges (1.75 % and 2.32 % strain ranges), GLARE displayed wide hysteresis loops with large deformation indicating that energy was more dissipated among the material. In high strain ranges, the predominant mechanism of failure was delamination along with secondary modes such as matrix cracking and fiber breakage. The Chaboche constitutive model was employed to model the cyclic behavior. This model predicted the nonlinearity of the deformation and the maximum flexural stress for the strain ranges studied in this work. The results validated the applicability of this model for characterizing the low-cycle fatigue performance of GLARE.
金属纤维层压板,特别是眩光(玻璃层压板铝增强环氧树脂),广泛应用于航空航天和汽车应用,由于其重量轻,高比强度和优异的抗疲劳性能。在1.13%、1.75%和2.32%的应变范围内,研究了眩光材料的循环弯曲行为,以评估其在循环载荷下的疲劳性能和退化情况。对金属体积分数为67%的Al 2024-T3和e-玻璃纤维增强环氧树脂层组成的眩光材料进行了循环三点弯曲试验。在低应变范围内(1.13%),眩光表现出最小塑性变形和能量耗散的弹性行为。另一方面,在较高的应变范围(1.75%和2.32%应变范围),眩光表现出宽的磁滞回线和大的变形,表明能量在材料之间的耗散更多。在高应变范围内,主要破坏机制为分层破坏,其次是基体断裂和纤维断裂。采用Chaboche本构模型对循环行为进行建模。该模型预测了所研究的应变范围内的变形和最大弯曲应力的非线性。结果验证了该模型对表征眩光低周疲劳性能的适用性。
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引用次数: 0
Selective activation of topological edge and corner states on dislocation interfaces 位错界面上拓扑边缘和角态的选择性激活
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-13 DOI: 10.1016/j.euromechsol.2025.105946
Yan Liu, Lifeng Wang, Yuping Tian, Yuqiang Gao
Topological edge and corner states have been demonstrated at the interfaces between two topologically distinct metamaterials. In this study, the topological edge and corner states of the dislocation interfaces between two elastic metamaterial plates with the same bulk lattice are investigated. Supercell analysis reveals that a bandgap emerges between the edge and bulk bands for two different dislocation interfaces. Multichannel structures containing both interfaces are designed, and selective activation and waveguide transmission of the edge states are observed. In addition to the edge states, antisymmetrical corner states with high localization are observed in metamaterial plates with triangular interfaces. The robustness of the corner states is demonstrated by introducing different types of imperfections near the corners. Moreover, the feature of selective activation is verified in a parallelogram-shaped structure, which facilitates the realization of elastic switches. This study provides a reference for manipulating elastic waves in topological metamaterials with a single bulk lattice.
拓扑边缘态和角态在两种拓扑不同的超材料之间的界面上得到了证明。本文研究了具有相同体点阵的两个弹性超材料板间位错界面的拓扑边态和角态。超级单体分析表明,在两种不同位错界面的边带和体带之间存在带隙。设计了包含两个界面的多通道结构,观察了边缘态的选择性激活和波导传输。在具有三角形界面的超材料板中,除了存在边缘态外,还存在高度局域化的不对称角态。通过在拐角附近引入不同类型的缺陷来证明拐角状态的鲁棒性。此外,在平行四边形结构中验证了选择性激活特性,便于弹性开关的实现。该研究为单块晶格拓扑超材料中弹性波的操纵提供了参考。
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引用次数: 0
Micromechanical constitutive modeling of bainitic rail steel with an evolving multiphase microstructure based on a two-step homogenization framework 基于两步均匀化框架的多相演变贝氏体轨道钢微观力学本构建模
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-07 DOI: 10.1016/j.euromechsol.2025.105931
Junjie Tang , Hailing He , Xiang Xu , Hu Liu , Yusong Fan , Guhui Gao , Ping Wang , Zefeng Wen , Qianhua Kan
This study develops a micromechanical constitutive model for advanced multiphase bainitic rail steel, which exhibits complex multi-mechanism behavior. A two-step homogenization framework integrates an interpolation Mori-Tanaka method and an extended Mori-Tanaka method to resolve the hierarchical relationship among constituent phases. By embedding microstructural characteristics and volume fraction evolution within this mean-field homogenization framework, a micromechanical multiphase constitutive model incorporating microstructural characteristics and evolution is constructed. Comparisons with experimental results demonstrate that the model accurately simulates the stress-strain responses and the evolution of retained austenite volume fraction during tensile testing of samples with varying microstructures. Furthermore, the model reliably predicts the observed trends in tensile strength and uniform elongation across different samples. Additionally, analyses of incremental step sensitivity and alternative homogenization frameworks confirm the model's robustness. Finally, the proposed model is applied to investigate the influence of bainitic-ferrite volume fraction, retained austenite stability, and strain-controlled cyclic loading on the overall mechanical behavior of bainitic rail steel.
本研究建立了具有复杂多机制行为的先进多相贝氏体轨道钢的细观力学本构模型。两步均匀化框架结合插值Mori-Tanaka方法和扩展Mori-Tanaka方法来解决组成相之间的层次关系。通过将微观组织特征和体积分数演化嵌入平均场均匀化框架,构建了包含微观组织特征和演化的微力学多相本构模型。与实验结果对比表明,该模型能较好地模拟不同组织试样拉伸过程中的应力应变响应和残余奥氏体体积分数的演变。此外,该模型可靠地预测了不同样品的抗拉强度和均匀伸长率的观察趋势。此外,对增量阶跃敏感性和可选均匀化框架的分析证实了模型的鲁棒性。最后,应用该模型研究了贝氏体-铁素体体积分数、残余奥氏体稳定性和应变控制循环加载对贝氏体钢轨钢整体力学行为的影响。
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引用次数: 0
Analysis of dynamic response characteristics of landing impact for a certain type of turboprop engine under coupled connection mode of fuselage-support frame-vibration isolator-engine system 机身-支撑架-隔振器-发动机耦合连接模式下某型涡桨发动机着陆冲击动态响应特性分析
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-07 DOI: 10.1016/j.euromechsol.2025.105937
Shuowen Shen, Zhineng Wang, Yang Pan, Jingyun Yang
In the aircraft fuselage-support frame-vibration isolator-engine coupled connection system, the vibration response characteristics of the engine under landing impact loading conditions exhibit complex dynamic characteristics. Excessive impact loads are prone to induce vibration amplitude exceeding the limit, dynamic instability of the entire aircraft, and even aircraft crashes, which severely endangers flight safety. This paper focuses on the study of the engine's landing impact characteristics under the coupled connection mode of fuselage-support frame-vibration isolator-engine. A system dynamics model under the coupled connection mode was established, and the finite element method was used to analyze the vibration characteristics of the engine under different impact velocities and angles. The research results show that the maximum error between the maximum magnitude obtained from FEM simulation and the experimental data is 5.9 %, which indicates that the FEM model can well simulate the impact landing conditions of the real engine. With increasing impact velocity, the maximum vibration reduction efficiencies of the front-left and front-upper vibration isolators are 60.82 % and 58.01 %, respectively. By analyzing the engine's response characteristics under different impact angles, it is concluded that under both sets of conditions, the rear side of the engine has higher dynamic loads and response amplitudes than the front side, resulting in a higher probability of rub-impact and damage.
在飞机机身-支撑架-隔振器-发动机耦合连接系统中,发动机在着陆冲击载荷条件下的振动响应特性表现出复杂的动态特性。过大的冲击载荷容易诱发振动幅值超过极限,导致整个飞机动力失稳,甚至导致飞机坠毁,严重危及飞行安全。本文重点研究了机身-支撑架-隔振器-发动机耦合连接模式下的发动机着陆冲击特性。建立了耦合连接方式下的系统动力学模型,采用有限元方法分析了发动机在不同冲击速度和角度下的振动特性。研究结果表明,有限元模拟得到的最大幅度与实验数据的最大误差为5.9%,表明有限元模型能较好地模拟真实发动机的冲击着陆条件。随着冲击速度的增加,前左隔振器和前上隔振器的最大减振效率分别为60.82%和58.01%。通过对不同冲击角度下发动机响应特性的分析,得出在两种情况下,发动机后侧面的动载荷和响应幅值都高于前侧面,从而导致发动机发生碰摩和损坏的概率更高。
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引用次数: 0
Growth-modulated natural shape and stiffnesses of elastic rods modeled as a special Cosserat rod 以特殊Cosserat杆为模型的弹性杆的生长调节自然形状和刚度
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-05 DOI: 10.1016/j.euromechsol.2025.105943
Roushan Kumar, Ajeet Kumar
In this study, a scheme is developed to obtain the natural shape and stiffnesses of rod-like growing elastic bodies modeled as a special Cosserat rod. The scheme allows the rod’s cross-section to have arbitrary shape. The rod material is also allowed to undergo arbitrary volumetric and surface growth. The Helical Cauchy–Born rule is employed to first generate a helical rod in which the rod’s strain parameters are imposed uniformly along its arclength. This uniformity in strain field leads to the reduction of three-dimensional nonlinear equations of morphoelasticity from the entire rod body to its cross-sectional plane. The governing equations for the deformation of the rod’s cross-section are then derived considering both volume and surface growth. Semi-analytical expressions of stress resultants and stiffnesses of the rod are further derived in terms of the rod’s prescribed strains, growth parameters and the unknown deformed cross-section. Upon setting the stress resultants to zero, one obtains the natural shape of the rod. A finite element formulation is also presented to solve the non-linear cross-sectional morphoelasticity problem. To elucidate our computational tool, several numerical simulations are performed involving volumetric uniform and differential axial growth, isotropic surface growth and active filaments.
本文提出了一种以特殊Cosserat杆为模型的棒状生长弹性体的自然形状和刚度求解方案。该方案允许杆的横截面具有任意形状。棒材也允许经历任意体积和表面增长。首先利用螺旋柯西-玻恩规则生成螺旋杆,其中杆的应变参数沿其弧长均匀施加。这种应变场的均匀性导致了从整个杆体到其横截面的三维非线性形态弹性方程的简化。然后推导了考虑体积和表面生长的棒材截面变形的控制方程。根据杆的规定应变、生长参数和未知变形截面,进一步导出了杆的应力和刚度的半解析表达式。将应力结果设为零,就得到了棒子的自然形状。提出了求解非线性截面形态弹性问题的有限元公式。为了阐明我们的计算工具,进行了几个数值模拟,包括体积均匀和微分轴向生长,各向同性表面生长和活性细丝。
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引用次数: 0
Enhanced super-harmonic resonance in piezoelectrically laminated curved microbeam resonators under fringing-field electrostatic actuation 压电层压弯曲微束谐振器在条纹场静电驱动下的超谐波增强
IF 4.2 2区 工程技术 Q1 MECHANICS Pub Date : 2025-11-05 DOI: 10.1016/j.euromechsol.2025.105941
Zahra Rashidi , Saber Azizi , Omid Rahmani
Achieving low-frequency MEMS resonators while maintaining the compact size of MEMS sensors has long been a challenge in MEMS design and fabrication. This study focuses on the super-harmonic resonance regions and associated bifurcation points of a curved microbeam sandwiched between two piezoelectric layers and subjected to fringing-field electrostatic actuation. The nonlinear equations of motion are derived, and the dependence of the electrostatic force on displacement is analysed using a finite element approach. The microbeam is excited by a combination of DC and AC electrostatic actuation, along with a tuning DC piezoelectric voltage. The influence of the piezoelectric voltage on the variation of the natural frequency under a given DC electrostatic excitation is examined. The frequency response curves are obtained over a broad excitation range, extending from below the primary resonance, through the super-harmonic regime, and beyond the primary resonance region. Bifurcation points are identified using Floquet multipliers. The results indicate that strong quadratic and cubic nonlinearities lead to the emergence of super-harmonic resonance zones of orders 1/2 and 1/3 in the frequency response, enabling the development of low-frequency resonators while retaining the advantages of MEMS-scale sensors. This effect is particularly significant in the design of MEMS energy harvesters, facilitating energy extraction from low-frequency mechanical noise. The simultaneous presence of nonlinearities of orders 1/2 and 1/3 and even higher orders generates multiple resonance zones within the super-harmonic regime, enabling the design of broadband low-frequency energy harvesters and MEMS wide-bandpass filters.
在保持MEMS传感器的紧凑尺寸的同时实现低频MEMS谐振器一直是MEMS设计和制造中的一个挑战。本文研究了夹在两个压电层之间的弯曲微梁在边缘场静电驱动下的超谐波共振区和相关的分岔点。推导了非线性运动方程,并用有限元方法分析了静电力对位移的依赖关系。微光束是由直流和交流静电驱动组合激发的,并伴随着可调谐的直流压电电压。研究了给定直流静电激励下压电电压对固有频率变化的影响。频率响应曲线是在一个很宽的激励范围内得到的,从主共振以下延伸到超谐波区,并超过主共振区。用Floquet乘法器识别分岔点。结果表明,较强的二次和三次非线性导致频率响应中出现1/2阶和1/3阶超谐波谐振区,使得低频谐振器的发展成为可能,同时保留了mems尺度传感器的优势。这种效应在MEMS能量采集器的设计中尤为重要,有助于从低频机械噪声中提取能量。1/2阶和1/3阶甚至更高阶的非线性同时存在,在超谐波范围内产生多个共振区,使宽带低频能量收集器和MEMS宽带带通滤波器的设计成为可能。
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引用次数: 0
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European Journal of Mechanics A-Solids
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