International Journal of Mechanical Sciences最新文献

{"title":"Turbulent melt lubrication and current-carrying dynamic characterizations of the contact interface under magneto-thermal effect","authors":"Guiwen Liao ,&nbsp;Yu Feng ,&nbsp;Kai Wu ,&nbsp;Shaolei Wu ,&nbsp;Qi Chen ,&nbsp;Wei Wang","doi":"10.1016/j.ijmecsci.2025.110052","DOIUrl":"10.1016/j.ijmecsci.2025.110052","url":null,"abstract":"<div><div>Under high-speed and high-temperature current-carrying conditions, turbulence in the metal liquefaction layer significantly influences friction interface performance, especially in a magneto-thermal shock environment. The interplay between turbulence and interface roughness complicates the dynamic behavior of hybrid lubrication and electrical contact. To explore the underlying mechanisms, this study constructs a turbulent melt lubrication model by integrating magnetic, temperature, and tribological calculations using the finite difference method (FDM). The findings reveal that armature velocity variations notably affect interface heat distribution, causing melt waves to propagate along the contact interface. As working conditions change, the primary heat source at the interface shifts from Joule heat to a combination of viscous and Joule heat (63.81 % and 36.19 %, respectively), demonstrating the complexity of the energy conversion process. Notably, the formation of a metal liquefied layer reduces the coefficient of friction and alters the lubrication state, which is crucial for optimizing the performance of electromagnetic launching system (EMLs).</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"289 ","pages":"Article 110052"},"PeriodicalIF":7.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of multiple cavitations near plate structures in underwater explosions","authors":"Yifan Zhang ,&nbsp;Liangtao Liu ,&nbsp;Jinxiang Wang ,&nbsp;Kun Liu ,&nbsp;Xiwen Chen ,&nbsp;Niannian Liu","doi":"10.1016/j.ijmecsci.2025.110047","DOIUrl":"10.1016/j.ijmecsci.2025.110047","url":null,"abstract":"<div><div>Multiple cavitations generated by near-field underwater explosions can cause significant structural damage, and its generation mechanisms and evolutionary characteristics are still unclear. Therefore, the characteristics of multiple cavitations near plates in underwater explosions are investigated experimentally and numerically. Multiple cavitations near air-backed plates with varying impedances are explored experimentally through a cavitation apparatus, and the effectiveness of Arbitrary Lagrangian–Eulerian method considering multiple cavitations in underwater explosions is validated by the experimental results. Based on the numerical method, the generation processes and evolutionary characteristics of multiple cavitations near air-backed plates at different detonation distances and near water-backed plates with different impedances are analyzed, where the influences of the explosion shock wave and bubble dynamics on evolutionary characteristics of multiple cavitations are commendably elucidated. On the basis of the liquid pressure and structural velocity, the generation mechanisms of multiple cavitations near the structure have also been well revealed. The results indicate that: Ⅰ. The first cavitation is mainly caused by rarefaction wave reflections or transmissions from the structure, which collapses quickly. The second cavitation is driven by negative pressure from liquid stretching due to structural oscillations, which collapses more slowly. Ⅱ. For air-backed plates, decreasing structural impedance increases the first cavitation diameter and delays second cavitation. Smaller detonation distances result in larger diameters and longer durations for cavitations. Ⅲ. For water-backed plates, when impedance is lower than water, cavitation diameters and durations increase as impedance decreases. However, when impedance exceeds water's, cavitation generation becomes difficult. Ⅳ. The third cavitation follows similar generation and evolution patterns as the second. These findings provide theoretical and technical support for revealing the complex mechanical mechanisms in near-field underwater explosions.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110047"},"PeriodicalIF":7.1,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deposition mechanism of microscopic impacting droplets on flexible porous substrates","authors":"Yankang Zhang ,&nbsp;Zhe Li ,&nbsp;Lin Li ,&nbsp;Chengyan Wang ,&nbsp;Jiafeng Wu ,&nbsp;Yuanshen Xie ,&nbsp;Zichao Yin ,&nbsp;Dapeng Tan","doi":"10.1016/j.ijmecsci.2025.110050","DOIUrl":"10.1016/j.ijmecsci.2025.110050","url":null,"abstract":"<div><div>Flexible and breathable porous pressure sensors are gaining attention due to their potential in wearable devices for human motion monitoring. The controllable deposition and transport of droplets on porous surfaces are critical for achieving high - conductivity printing in flexible and wearable sensors, as well as in electronic applications. Due to the intricate microstructure of porous layers, accurately dynamically tracking alterations in droplet morphology and the detailed characterization of multiphase-coupled transport present significant challenges. To address these issues, this study employs a microscopic multiphase-coupled transport dynamics model based on the volume-of-fluid smoothing correction and the Kistler dynamic contact angle model (VOFS-KCA). The aim is to investigate the evolution of droplet transport on both the external surface and internal pore spaces of porous media. Furthermore, it reveals the correlation between the structural characteristics of porous media and the mass transfer process in multiphase flow. Results show that the wettability of porous surfaces is a pivotal factor in droplet clusters' dispersion and mobility. The effect of porosity on droplet penetration is nonlinear. Appropriate porosity is conducive to droplet penetration on the porous surface, while excessive porosity leads to lateral diffusion in the cavity. A smaller fiber diameter leads to an approximately circular and uniform distribution of droplets on the porous surface and reduces permeability, which is conducive to maintaining the linewidth of the printed circuit and improving the conductivity. This study systematically explores how surface wettability, porosity, and fiber structure affect droplet dispersion and infiltration, providing new insights into the design of high-performance porous systems. This work lays the foundation for the high-precision manufacturing of flexible sensors with porous surfaces, with applications in energy storage, filtration, and biomedical systems.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110050"},"PeriodicalIF":7.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Locally activated 4D printing with programmable shapes and properties","authors":"Xueli Zhou ,&nbsp;Chubang Tian ,&nbsp;Jifeng Zhang ,&nbsp;Luquan Ren ,&nbsp;Lei Ren","doi":"10.1016/j.ijmecsci.2025.110038","DOIUrl":"10.1016/j.ijmecsci.2025.110038","url":null,"abstract":"<div><div>This study innovatively proposes a locally activated magnetically responsive 4D printing strategy to solve the problem of local deformation of magnetic shape memory composites. The local activation scheme is designed to precisely regulate the thermal activation area and magnetic field parameters, and the deformation behavior of the composites can be finely controlled. In addition, the strategy is applied to the shape tuning of the dome and chiral structures, which realizes the intelligent programming of structural energy absorption properties. This study opens up new avenues for the design and fabrication of adaptive and reconfigurable active mechanical metamaterials, minimally invasive medical implantable devices, and flexible electronic devices.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110038"},"PeriodicalIF":7.1,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stepwise self-oscillation of a photo-oscillator via time delay","authors":"Zhuangzhuang Zhang,&nbsp;Xinyan Jiang,&nbsp;Yunlong Qiu,&nbsp;Kai Li","doi":"10.1016/j.ijmecsci.2025.110046","DOIUrl":"10.1016/j.ijmecsci.2025.110046","url":null,"abstract":"<div><div>Self-oscillating systems, characterized by ambient-energy-supply and self-control, can absorb energy from steady environment to sustain continuous motion, whereas traditional self-oscillations rely on inertia and require rapid response to excitations. This study introduces a time-delay mechanism to experimentally design a photo-oscillator based on liquid crystal elastomers (LCEs), demonstrating stepwise self-oscillation without requiring a rapid response of the LCE to stimuli. The time delay is realized using a bistable seesaw system and is explained through the time history of the stepwise self-oscillation. Through quasi-static analysis, critical positions determined by geometric conditions are calculated, revealing the photo-oscillator alternates continuously between two stable states. Furthermore, the influence of system parameters on the critical contraction and period is investigated. Unlike many existing self-oscillating systems, the proposed photo-oscillator features a simple structure, a wide controllable oscillation period, and minimal requirements, relying only on small-area line illumination. The findings of this study hold promise for expanding design concepts applicable to soft robotics, sensors, and energy harvesters.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110046"},"PeriodicalIF":7.1,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of modular deployable structure with programmable multistability","authors":"Fengrui Liu ,&nbsp;Tatsuro Terakawa ,&nbsp;Ji Lin ,&nbsp;Masaharu Komori","doi":"10.1016/j.ijmecsci.2025.110037","DOIUrl":"10.1016/j.ijmecsci.2025.110037","url":null,"abstract":"<div><div>Origami-inspired deployable structures have extreme compactness and design flexibility, suitable for aerospace structures, disaster relief robots, and medical devices. However, due to the lack of rigid-foldability, many origami applications rely on soft materials, limiting their load-bearing capacity and range of applications. To address this issue, this study proposes an origami design called Foldable Cube origami (FC-ori), which allows a cube to be rigidly folded into a square. By adding a translational degree of freedom along the rotational axis on some creases, FC-ori effectively mitigates the effects of thickness while preserving both rigid and flat foldability. By attaching various magnets and springs, an FC-ori unit can exhibit programmable multistability. Utilizing these units, we designed a modular, deployable mobile robot that can adapt to various terrains and tasks by transforming its configuration, demonstrating the potential of FC-ori in rigid origami applications.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110037"},"PeriodicalIF":7.1,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micro-mechanism of mechanical enhancement of NiTiAl amorphous-crystal nanomultilayers","authors":"Yuanwei Pu ,&nbsp;Yongchao Liang ,&nbsp;Yu Zhou ,&nbsp;Qian Chen ,&nbsp;Tinghong Gao ,&nbsp;Lili Zhou ,&nbsp;Zean Tian","doi":"10.1016/j.ijmecsci.2025.110020","DOIUrl":"10.1016/j.ijmecsci.2025.110020","url":null,"abstract":"<div><div>Amorphous-crystal nanomultilayers (ACNMs) exhibit outstanding mechanical properties, but the micro-mechanisms responsible for the enhancement of their mechanical performance remain incompletely understood. Molecular dynamics (MD) simulations were performed on the tensile processes of NiTiAl ACNMs to examine the microstructure evolutions during deformation in crystals, amorphous (MGs), and crystal-amorphous interfaces (CAIs). ACNMs increase in strength and decrease in plasticity with decreasing interface spacing. The MGs layer can accommodate larger strains. The intense competition among shear transformation zones (STZs) mitigates strain localization in MGs and boosts the plasticity of ACNMs. In the crystal layer, the main plastic deformation mechanism is that FCC clusters are disrupted and converted into other MGs clusters. As the interface spacing decreases, the geometrically constrained dispersion of STZs boosts material strength. The self-developed Largest Standard Cluster Analysis (LaSCA) method was employed to accurately depict the microstructure evolution of CAIs. The CAIs are responsible for strain transmission and induce dislocation accumulation in their vicinity, leading to localized strain. This study elucidates the microstructural changes in ACNMs during tensile deformation, offering insights for optimizing their mechanical properties through interface spacing design.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110020"},"PeriodicalIF":7.1,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic modeling and analysis for dielectric elastomer tube actuators","authors":"Yuqing Guo ,&nbsp;Liang Li ,&nbsp;Dingguo Zhang ,&nbsp;Wei-Hsin Liao","doi":"10.1016/j.ijmecsci.2025.109994","DOIUrl":"10.1016/j.ijmecsci.2025.109994","url":null,"abstract":"<div><div>Dielectric elastomer tubular actuators (DETA) as a new type of smart material actuator, has attracted wide attention in recent years. Its basic working principle is to use the deformation generated by dielectric elastomers (DEs) under the electric field to achieve the actuation function. Compared with the traditional actuators, DETA has the advantages of high energy density, fast response, simple structure, lightweight, soft and large deformation. In engineering applications, good structural design can improve the efficiency of actuation, reduce energy loss and prolong service life. The purpose of this paper is to explore the electromechanical coupling principle of DETA. Based on the Absolute Nodal Coordinate Formulation (ANCF), we use the electromechanically coupled 8-node hexahedral element, and consider the viscoelastic properties of the material to derive the dynamic equations of the flexible system containing DETA. Subsequently, the static and dynamic behaviors of the system are studied, and the correctness and validity of the method proposed in this work are verified by comparing with the experimental results. The research in this paper not only enriches the modeling and theoretical analysis of DEs, but also provides new ideas and methods for its application.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 109994"},"PeriodicalIF":7.1,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vibro-acoustic suppression in metamaterial sandwich plate using compressional-torsional coupling resonator","authors":"Rui Zhang ,&nbsp;Wei Ding ,&nbsp;Hao Liu ,&nbsp;Peicheng Feng ,&nbsp;Weizhe Ding ,&nbsp;Tianning Chen ,&nbsp;Jian Zhu","doi":"10.1016/j.ijmecsci.2025.110039","DOIUrl":"10.1016/j.ijmecsci.2025.110039","url":null,"abstract":"<div><div>Reducing low-frequency vibration and sound radiation in lightweight sandwich structures remains a significant challenge due to the inherently long wavelength of low-frequency waves. In this study, we proposed a novel metamaterial sandwich plate with compressional-torsional coupling inertial amplification resonators to effectively attenuate low-frequency vibration and suppress sound radiation. The sandwich plate is integrally fabricated by 3D printing technology. A theoretical model for bandgap prediction is developed using Hamilton's principle. Theoretical, numerical, and experimental results converge to demonstrate that the proposed metamaterial sandwich plate exhibits superior low-frequency bandgap performance while ensuring the lightweight and compactness of the structure. The bandgap starting frequency of the compressional-torsional coupling resonator is 45 % lower than that of the conventional resonator, despite having identical mass and stiffness. Moreover, for the same bandgap starting frequency and stiffness, its mass is only 30 % of that of the conventional counterpart. Crucially, it also occupies significantly less space compared to the lever-type inertial amplification local resonator. This work introduces a promising strategy for the reduction of low-frequency vibration in engineering applications.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110039"},"PeriodicalIF":7.1,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Snap-through behaviors of bistable composite panel in centrifugal environments","authors":"Pengpeng Liu,&nbsp;Jie Tang,&nbsp;Yang Guo,&nbsp;Yinghui Li","doi":"10.1016/j.ijmecsci.2025.110036","DOIUrl":"10.1016/j.ijmecsci.2025.110036","url":null,"abstract":"<div><div>In this paper, a cross-well dynamics model of bistable composite panels in centrifugal environments is proposed. The external excitation applied at the four corners is assumed to be a uniformly distributed harmonic acceleration. Nonlinear equations are derived by combining geometric nonlinearity, thermal stresses, and centrifugal effects with the first-order shear deformation theory, and are expressed in terms of curvature. Additionally, the maximum Lyapunov exponent is used to classify vibration types. Observations of periodic and chaotic snap-throughs are categorized into vibration type domains. To facilitate understanding, bifurcation diagrams, phase portraits, time histories, and Poincaré maps are presented for representative operating conditions. The effects of centrifugal environments, external excitation amplitude, and frequency on snap-through behavior are thoroughly investigated. The results show that there exists a critical static angular velocity, beyond which the panel cannot maintain bistability, and indicate that snap-through behavior in bistable panels is caused by negative stiffness due to residual thermal stresses. Bistable composite panels exhibit both forward and backward bouncing. Furthermore, three types of frequencies are identified: upper Stable I frequency, lower Stable II frequency, and snap-through frequency. It is also noted that the impact of angular velocity on these frequencies is not uniform. When the external excitation frequency approaches one stable state frequency, it can destabilize the configuration, causing vibrations to occur in the other configuration.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"288 ","pages":"Article 110036"},"PeriodicalIF":7.1,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143295505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}