International Journal of Non-Linear Mechanics最新文献

{"title":"Model reduction of a flexible nonsmooth oscillator recovers its entire bifurcation structure","authors":"Suparno Bhattacharyya,&nbsp;Joseph P. Cusumano","doi":"10.1016/j.ijnonlinmec.2025.105194","DOIUrl":"10.1016/j.ijnonlinmec.2025.105194","url":null,"abstract":"<div><div>We study the reduced order modeling of a piecewise-linear, globally nonlinear flexible oscillator in which a Bernoulli–Euler beam is subjected to a position-triggered kick force and a piecewise restoring force at its tip. The nonsmooth boundary conditions, which determine different regions of a hybrid phase space, can generally be expected to excite many degrees of freedom. With kick strength as parameter, the system’s bifurcation diagram is found to exhibit a range of periodic and chaotic behaviors. Proper orthogonal decomposition (POD) is used to obtain a single set of global basis functions spanning all of the hybrid regions. The reduced order model (ROM) dimension is chosen using previously developed energy closure analysis, ensuring approximate energy balance on the reduced subspace. This yields accurate ROMs with 8 degrees of freedom. Remarkably, we find that ROMs formulated using data from individual periodic steady states can nevertheless be used to reconstruct the entire bifurcation structure of the original system without updating. This demonstrates that, despite being constructed with steady state data, the ROMs model sufficiently small transients with enough accuracy to permit using simple continuation for the bifurcation diagram. We also find ROM subspaces obtained for different values of the bifurcation parameter are essentially identical. Thus, POD augmented with energy closure analysis is found to reliably yield effective dimension estimates and ROMs for this nonlinear, nonsmooth system that are robust across stability transitions, including even period doubling cascades to chaos, thereby greatly reducing data requirements and computational costs.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105194"},"PeriodicalIF":2.8,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144557423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation into energy harvesting from a non-linear aeroelastic system subjected to stochastic loads","authors":"Manan V. Jain ,&nbsp;Rajesh Senthil Kumar T. ,&nbsp;S. Narayanan ,&nbsp;J. Venkatramani","doi":"10.1016/j.ijnonlinmec.2025.105193","DOIUrl":"10.1016/j.ijnonlinmec.2025.105193","url":null,"abstract":"<div><div>There is growing interest to harvest energy from aeroelastic oscillations — with the goal of making several small power devices self-reliant. While a considerable success has been achieved in understanding the optimal range of parameters required for succinct aeroelastic energy harvesting, translating these developments to in-field conditions is fraught with difficulties. A prominent challenge that is ubiquitous in in-field conditions is the presence of ambient wind fluctuations. These wind fluctuations are often random and vary across different scales of spatial and temporal variables. Further, from an aerodynamic point of view, these stochastic wind fluctuations could either be axial, i.e., along the direction of the chord line of the airfoil, or could be in the vertical direction, i.e., perpendicular to the chord line of the airfoil. The former gives rise to a multiplicative noise, and the latter yields to be an additive noise to the existing dynamical system (airfoil). The energy harvesting potential under these stochastic wind gusts is minimally explored in the hitherto literature and are far from complete. Addressing this end-of-concern forms the pivotal focus of this study. To that end, a pitch–plunge airfoil with cubic hardening nonlinearity in the pitch stiffness is considered. A piezoelectric transducer (PZT) is attached to the elastic axis of the airfoil. A numerical approach is used to solve the aeroelastic system coupled with an energy harvesting mechanism undergoing stochastic wind fluctuations to determine the voltage output and the harvested power. As a first step, the deterministic bifurcation scenario, along with the energy harvesting potential, is presented. Subsequently, the energy harvesting potential under longitudinal turbulence, vertical turbulence, and combined longitudinal and vertical turbulence is provided. Results indicate that vertical turbulence, in particular, produces continuous oscillations even below the <em>so-called</em> flutter velocity, enabling effective energy harvesting capabilities unlike its longitudinal counterpart. Given the ubiquitous presence of vertical wind gusts and a variety of aeroelastic devices, the findings from this study underscore the impact of various turbulence components on power output, along with offering insights into optimizing energy harvesting for real-world applications.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105193"},"PeriodicalIF":2.8,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144549772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact response and optimization of reinforced concrete slabs under dynamic loading: A finite element analysis study","authors":"Md Jamirul Islam ,&nbsp;Mohd Abu Bakr ,&nbsp;Muhammad Farhan ,&nbsp;Md. Maqubool Hosain ,&nbsp;S.M.Mozammil Hasnain","doi":"10.1016/j.ijnonlinmec.2025.105200","DOIUrl":"10.1016/j.ijnonlinmec.2025.105200","url":null,"abstract":"<div><div>This study investigates the behaviour of reinforced concrete (RC) slabs under impact loading using Finite Element Analysis (FEA) in ABAQUS/CAE. A 760 mm × 760 mm × 76 mm RC slab model was developed with material properties calibrated for both linear and nonlinear behaviour using the Drucker-Prager plasticity model. Simulations were conducted across boundary conditions, impact velocities, and reinforcement configurations. Results revealed that maximum displacement occurred in slabs with one side fixed (12.4 mm) compared to fully fixed slabs (6.8 mm). Boundary conditions significantly influenced stress distribution, with maximum von Mises stress recorded at 38.5 MPa for the cantilever case and 25.2 MPa for fully fixed conditions. Increasing impact velocity from 4500 mm/s to 7200 mm/s increased displacement from 8.6 mm to 14.1 mm and stress from 22.4 MPa to 41.7 MPa, stabilizing beyond 6500 mm/s. Replacing traditional reinforcement with a steel plate reduced displacement by 22 % and improved stress distribution, while reducing the steel plate volume by 40 % resulted in a 15 % increase in displacement. These findings underscore the importance of boundary conditions, material non-linearity, and optimized reinforcement design for predicting RC slab responses under dynamic loads, offering key insights for improving structural resilience in high-impact scenarios.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105200"},"PeriodicalIF":2.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144535505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large amplitude vibrations and nonlinear dynamics characteristics of an autoparametric pendulum absorber-harvester","authors":"Ao Zhang ,&nbsp;Zhanxiang Gao ,&nbsp;He Li ,&nbsp;Ping Han ,&nbsp;Zhenting Song ,&nbsp;Wenda Yu","doi":"10.1016/j.ijnonlinmec.2025.105201","DOIUrl":"10.1016/j.ijnonlinmec.2025.105201","url":null,"abstract":"<div><div>This study investigates the nonlinear dynamics of a pendulum absorber-harvester system under large swing angle conditions, addressing the dual objectives of vibration absorption and energy harvesting. The dynamic model of the absorber-harvester system is established and the bifurcation characteristics and chaotic motion is analyzed by a numerical method. The results indicate that the system could exhibit three distinct motion patterns within the absorption bandwidth: stable periodic motion, quasi-periodic motion, and chaotic motion. Experiment validation is conducted to verify the different motion patterns and assess the system's vibration absorption efficiency and energy harvesting performance. Furthermore, the impact of key parameters on system's dynamic response is evaluated. The findings reveal that when chaotic motion occurs within the absorption bandwidth, the left stable region can reduce the vibration amplitude of the main system, while the right stable region could increase the vibration amplitude of the main system. Also, multiple chaotic motion regions would occur under certain parameters, which could be beneficial for energy harvesting but not conducive to vibration absorption. A stable full-circle rotation motion region of the pendulum exists between two chaotic regions, and this region is beneficial for both vibration absorption and energy harvesting. The nonlinear dynamic characteristics of the absorber-harvester system exhibit significant parameter dependence, enabling practical adjustments to meet specific application requirements.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105201"},"PeriodicalIF":2.8,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lie symmetry and variational analysis of a blood flow model with body forces","authors":"Debendra Prasad Panda,&nbsp;Manoj Pandey","doi":"10.1016/j.ijnonlinmec.2025.105191","DOIUrl":"10.1016/j.ijnonlinmec.2025.105191","url":null,"abstract":"<div><div>This work presents a comprehensive analysis of a one-dimensional nonlinear blood flow model that incorporates a body force term, using both Eulerian and Lagrangian descriptions. By introducing Lagrangian coordinates, the system is reformulated as a single second-order partial differential equation derived from a variational principle. Lie symmetry analysis is performed in both coordinate systems, leading to the construction of one-dimensional optimal systems and exact invariant solutions. Variational symmetries satisfying Noether’s criterion are identified, and the associated conservation laws are obtained using Noether’s theorem. Finally, the evolution of weak discontinuity waves is investigated using an exact solution, revealing important nonlinear effects such as wave steepening and shock formation. The results highlight the role of symmetries and conservation laws in understanding wave behavior in physiological flow models.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105191"},"PeriodicalIF":2.8,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling the finite deformation of thermoplastic polymers via hyperinelasticity, Part II: An amorphous polymer with varying rubber content-, rate- and temperature-dependency","authors":"Afshin Anssari-Benam ,&nbsp;Fahmi Zaïri","doi":"10.1016/j.ijnonlinmec.2025.105182","DOIUrl":"10.1016/j.ijnonlinmec.2025.105182","url":null,"abstract":"<div><div>In Part I we presented the application of the <em>hyperinelasticity</em> modelling approach to the large elastic and inelastic deformations of semi-crystalline polymers. In this sequel we extend the application of this model to the finite strains of amorphous polymers, by studying Poly(methyl methacrylate), i.e., PMMA, and rubber-toughened PMMA (RT-PMMA) polymer systems. The effects of variation in rubber particle content, temperature and deformation rate on the elastic and inelastic mechanical behaviour of the specimens will be examined and modelled, under large uniaxial compression. The <em>core</em> model will be calibrated using base-line behaviours (i.e., quasi-static deformation, zero particle content, ambient temperature etc.), and the <em>augmented</em> model will be shown to favourably capture the effects of the foregoing inelasticity-inducing factors on the deformation behaviour of the samples. The augmentation of the core model is achieved by considering a linear evolution of the core model parameters, as the function of, e.g., particle content, deformation rate, temperature etc. <em>Predictions</em> of the elastic and inelastic behaviours at intermediary values of temperature/rubber content etc will also be made, and will be verified against experimental data to demonstrate the close match between the two. Given the success of the modelling approach in these applications and in Part I, this two-part contribution concludes a <em>unified</em> modelling tool for application across various thermoplastic polymers, from semi-crystalline to amorphous polymer types. Such a model allows exploration and prediction of the shift in the material response of semi-crystalline polymers from a thermoplastic-like to a rubber-like behaviour, and the reshaping of the amorphous matrix response in the presence of inelasticity-inducing effects for amorphous polymers, using a unified modelling approach.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105182"},"PeriodicalIF":2.8,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144557422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soliton inspired hybrid active vibration control method for shock-induced transient vibrations: Numerical perspective","authors":"Serkan Guler","doi":"10.1016/j.ijnonlinmec.2025.105198","DOIUrl":"10.1016/j.ijnonlinmec.2025.105198","url":null,"abstract":"<div><div>A novel hybrid control approach has been designed with the primary objective of minimizing vibration amplitude as quickly and effectively as possible, particularly in response to mechanical shocks. The control approach taken in this study is a hybrid methodology based on the integration of the soliton-inspired wave and the conventional Proportional-Integral-Derivative (PID) control technique. The proposed hybrid control approach is compared with the conventional PID control technique considering two-DOF, four-DOF and five-DOF vibratory systems. Mathematical models of these vibratory systems are established and simulated numerically. In these simulations, it was found that the presented control technique further mitigates vibrations than conventional PID. Moreover, to investigate the applicability of the hybrid control methodology in this research to real engineering systems, a half-vehicle model and bolted cantilever beams are considered. Numerical simulation studies are carried out for these two different engineering systems. Through numerical simulation studies conducted on these systems, it was revealed that the proposed hybrid control approach exhibits superior active vibration control performance to the conventional PID method.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105198"},"PeriodicalIF":2.8,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Free vibration and large deformation characteristics of metamaterial thickness-deformable plates with initial geometrical imperfection","authors":"Behrouz Karami ,&nbsp;Mergen H. Ghayesh ,&nbsp;Shahid Hussain","doi":"10.1016/j.ijnonlinmec.2025.105190","DOIUrl":"10.1016/j.ijnonlinmec.2025.105190","url":null,"abstract":"<div><div>A geometrically imperfect third-order auxetic metamaterial thickness- and shear-deformable plate is considered, and both the non-linear bending as well as the free vibrations are analysed. Distribution of the effective material properties from plate’s top surface to the bottom one follows a functionally graded form; material properties are effectively approximated via genetic programming-assisted micromechanics models from previous studies. Without ignoring geometrical non-linearities, the fourfold coupled axial, transverse, rotational, and stretching non-linear motion equations are formulated for a geometrically imperfect third-order auxetic metamaterial thickness- and shear-deformable plate using Hamilton’s principle. The generalised differential quadrature method is implemented to discretise the motion equations; the discretised motion equations are then solved for both the non-linear bending as well as the linear free vibrations. For partial validation, the model is compared with available data from the open literature for simplified cases (i.e., single-layer homogeneous plates without metamaterial characteristics) and with a single-layered isotropic rectangular perfectly straight plate modelled in ANSYS. The complex non-linear mechanics and linear free vibration of the metamaterial system are analysed for different geometrical parameters, graphene origami contents, folding degrees, and geometrical imperfections, and also for both the symmetric and asymmetric distribution patterns of graphene origami. The results reveal that the geometric imperfections reduce the transverse deflection, and metamaterial plates with asymmetric graphene origami distributions consistently have the largest non-linear deflections among all the graphene origami distributions studied.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105190"},"PeriodicalIF":2.8,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144513728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear buckling analysis of helicoidal composite panels with curvilinear stiffeners","authors":"Xin Lian ,&nbsp;Haotian Wei ,&nbsp;Weidong Zhang ,&nbsp;Yuming Mao ,&nbsp;Dongjie Jiang ,&nbsp;Zhefeng Yu","doi":"10.1016/j.ijnonlinmec.2025.105195","DOIUrl":"10.1016/j.ijnonlinmec.2025.105195","url":null,"abstract":"<div><div>This study introduces a semi-analytical method designed to efficiently and accurately analyze the nonlinear buckling response of complex curvilinear stiffened panel structures, addressing the computational challenges associated with such designs. The proposed method establishes displacement compatibility conditions to couple stiffeners and base plate, while employing Legendre polynomials to expand displacement fields, thereby enhancing robustness and accuracy. The Ritz method is utilized to solve the nonlinear buckling equations, yielding equilibrium path deviations consistently below 5 % compared to finite element method results while achieving a 61.43 % reduction in computation time. Parametric studies conducted under uniaxial and biaxial compressive loads confirm the capability of the method to accurately capture the nonlinear buckling behavior of curvilinear stiffened panels. The findings reveal a reduction in nonlinear critical loads, approximately 20 % lower than those predicted by linear buckling analysis, emphasizing the necessity of nonlinear analysis for accurate system evaluation. The study underscores the potential of the proposed semi-analytical method as a reliable and computationally efficient tool for nonlinear buckling analysis in complex stiffened structures.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105195"},"PeriodicalIF":2.8,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144670708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geometrically nonlinear oscillations of composite sandwich cylindrical shell with honeycomb core under axial time periodic force","authors":"B. Uspensky ,&nbsp;K. Avramov ,&nbsp;S. Malyshev ,&nbsp;O. Nikonov","doi":"10.1016/j.ijnonlinmec.2025.105196","DOIUrl":"10.1016/j.ijnonlinmec.2025.105196","url":null,"abstract":"<div><div>Cylindrical composite sandwich shell, which consists of two outer layers and thick honeycomb core, is considered. The outer thin layers are manufactured from composite orthotropic material and honeycomb core is manufactured from orthotropic plastic.</div><div>Parametric nonlinear oscillations of cylindrical shell under the action longitudinal time periodic force are considered. The honeycomb core is homogenized. As a result, orthotropic solid continuum is obtained. Stressed state of every layer is described by higher order shear theory, which uses five generalized displacements (three displacements projections and two rotations angles of normal to middle surfaces). The assumed-mode method is applied to obtain the system of nonlinear ordinary differential equations with respect to the generalized coordinates to describe the sandwich structure vibrations.</div><div>The shooting technique and continuation method are applied jointly to analyze the nonlinear oscillations, their stability and bifurcations. The geometrically nonlinear oscillations are considered in the principal parametric resonances with account of internal resonances. Stability and bifurcations of periodic motions are shown on the frequency response, which describes the structure nonlinear dynamics in principle parametric resonances.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"178 ","pages":"Article 105196"},"PeriodicalIF":2.8,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144511063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}