Article
Mechanics
S. Ceballes, B. E. Saunders, A. Abdelkefi
Summary: The study focuses on extending the reliable reduced-order models of a carbon nanotube-based mass sensor using Timoshenko beam theory and Eringen's nonlocal theory. The discrepancies and limits of applicability between Timoshenko and Euler-Bernoulli models are deeply explored, showing that the nonlocal Timoshenko-based model is valuable for mass sensing applications, especially for short and stout structures. Researchers can utilize these findings for the design, modeling, and analysis of nanoscale sensors and resonators.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2022)
Article
Mechanics
Yu-Chi Su, Tse-Yu Cho
Summary: The free vibration of a single-walled carbon nanotube embedded in an elastic medium is studied using a nonlocal Timoshenko beam model. It is found that the nonlocal effect significantly influences the natural frequencies of the SWCNT in higher modes, especially when the SWCNT has a small slenderness ratio and is embedded in a soft elastic medium.
JOURNAL OF MECHANICS
(2021)
Article
Mathematics, Applied
Kalyan Boyina, Raghu Piska
Summary: This work investigates wave propagation in a viscoelastic Timoshenko nanobeam under the influence of surface stress and magnetic field effects. The study provides a mathematical model and closed-form solutions for such scenarios. The results indicate that the introduction of surface stress values increases the damping ratio of flexural and shear waves.
APPLIED MATHEMATICS AND COMPUTATION
(2023)
Article
Mechanics
H. M. Numanoglu, H. Ersoy, O. Civalek, A. J. M. Ferreira
Summary: This article examines the free thermal vibration analysis of nanobeams surrounded by an elastic matrix using nonlocal elasticity and Timoshenko beam theories. The equation of motion for free vibration is solved by analytical method, and a weighted residue-based finite element formulation is developed for boundary conditions other than simply supported nano beams. Numerical results show the high accuracy of the nonlocal finite element formulation and the effects of size dependency and environmental factors on the dynamic behavior of nanobeams are discussed in detail.
COMPOSITE STRUCTURES
(2021)
Article
Mathematics, Applied
Pei Zhang, P. Schiavone, Hai Qing
Summary: A nonlocal study of vibration responses of FG beams supported by a viscoelastic Winkler-Pasternak foundation is conducted, considering the damping responses of both the Winkler and Pasternak layers of the foundation. The bending deformation of the beams and the elastic and damping responses of the foundation are comprehensively considered by uniting differential formulations of strain-driven and stress-driven two-phase local/nonlocal integral models, addressing the stiffness softening and toughening effects. The GDQM is used to solve the complex eigenvalue problem, and benchmark results for vibration frequency are obtained.
APPLIED MATHEMATICS AND MECHANICS-ENGLISH EDITION
(2023)
Article
Mathematics, Applied
Hayri Metin Numanoglu, Hakan Ersoy, Bekir Akgoz, Omer Civalek
Summary: This study investigates the size-dependent thermo-mechanical vibration analysis of nanobeams by implementing Hamilton's principle and the stress equation of nonlocal elasticity theory. The finite element method is used to solve the eigenvalue problem and derive stiffness and mass matrices. Nonlocal finite element method is emphasized for analyzing the vibration behavior of nanobeams under different boundary conditions.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2022)
Article
Materials Science, Multidisciplinary
Hooman Danesh, Mahdi Javanbakht
Summary: This study investigates the free vibration behavior of nonlocal nanobeams using different kernel theories, finding a softening effect of the nonlocal parameter on natural frequencies. The 2D-NIET theory is more sensitive to the nonlocal parameter compared to NITBT.
MATHEMATICS AND MECHANICS OF SOLIDS
(2022)
Article
Mechanics
D. Wu, Y. Lei, Z. Wang, B. Yu, D. Zhang
Summary: The scale effect of carbon nanotubes (CNTs) in macro CNT-reinforced composites (CNTRCs) is analyzed, and the free vibration characteristics of a CNT-reinforced composite beam resting on a viscoelastic foundation were studied. A nonlocal EMT constitutive equation considering the scale effect of CNTs in the macro CNTRCs is proposed using the nonlocal theory and the EMT method. The governing equations and boundary conditions of the CNT-reinforced composite beam on a viscoelastic Pasternak foundation are obtained, and a solution for the free vibrations of the composite beam under simply supported boundary conditions is found, verifying the reliability of the model and solution method used through comparative analysis.
MECHANICS OF COMPOSITE MATERIALS
(2023)
Article
Mathematics, Applied
Maysam Naghinejad, Hamid Reza Ovesy
Summary: The viscoelastic buckling and nonlinear post-buckling behavior of nano-scaled beams were analyzed using the nonlocal integral elasticity theory. The study developed a finite element method and considered buckling related terms and viscoelastic effects. The results were compared with literature and the effects of nonlocal parameter, viscoelastic parameter, axial compressive load, and boundary conditions on the buckling and post-buckling behavior were investigated.
ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK
(2022)
Article
Physics, Condensed Matter
Jingjing Feng, Huajian Yu, Sai Ma, Shuying Hao, Ruiqin Wu
Summary: This paper examines the axial vibration behavior of mass sensors based on single-walled carbon nanotubes and establishes frequency equations and response relationships to describe their vibration characteristics. By combining theoretical analysis and molecular dynamics simulations, the influence of various physical factors on vibration behavior is studied, and methods to improve sensitivity are proposed.
PHYSICA B-CONDENSED MATTER
(2022)
Article
Materials Science, Multidisciplinary
Yu-Chi Su, Tse-Yu Cho
Summary: This article investigates wave propagation in embedded single-walled carbon nanotubes by modeling them as nonlocal Timoshenko beams. The analysis reveals that small scale effects smooth out transient responses and result in instantaneous wave propagation. The behavior of wave propagation is affected by the radius of the carbon nanotube, but not by its chirality. The dispersion relations with different small scale parameters are also examined.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2023)
Article
Mechanics
Farshad Khosravi, Seyyed Amirhosein Hosseini
Summary: This article investigates the forced and free dynamic torsional vibrations of single-walled carbon nanotubes embedded in a viscoelastic medium under a harmonic external torque. It introduces Eringen's nonlocal elasticity to consider the small size effect of nanostructures. The governing equation is simplified to an ordinary differential equation using the Galerkin method in the time domain. The study explores the effects of various parameters on the angular displacement, including the nonlocal parameter, damping ratio, damping coefficient, stiffness of the viscoelastic medium, excitation frequency, geometry, and mass moment of inertia. The results are validated using a finite difference method and compared with a previous study.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Mechanics
Hao Gao, Bingen Yang, Yegao Qu, Guang Meng
Summary: This paper proposes a new beam-moving rigid body model with distributed viscoelastic coupling to accurately describe the coupling between a structure and moving subsystems. Numerical simulations investigate the dynamic response of the beam structure and the effect of system configuration on its behavior.
Article
Chemistry, Multidisciplinary
Kun Huang, Wei Xu
Summary: Although the individual effects of small-scale effect and thermal stress on nanobeams have been studied, their combined effects and the temperature dependence of elastic parameters have not been thoroughly investigated. In this paper, a new nonlocal nonlinear Euler-Bernoulli theory is proposed to model the mechanical properties of nanobeams, considering both small-scale effect and thermal stress, as well as the temperature dependence of Young's modulus. The study demonstrates that thermal stress and temperature dependence have a significant influence on the mechanical properties of slender nanobeams, compared to the small-scale effect induced by the nonlocal effect. Neglecting the temperature effect may lead to qualitative errors in the analysis of slender nanobeams.
Article
Mathematics, Applied
Muhammad I. Mustafa
Summary: This paper investigates a Timoshenko system under the combined effect of frictional damping and viscoelastic damping, establishing explicit and optimal energy decay rates for the system for the first time. The result generalizes and improves upon earlier related findings in the literature.
MEDITERRANEAN JOURNAL OF MATHEMATICS
(2021)
Article
Acoustics
Kartheek Amaroju, Kiran Vijayan, Michael Friswell
Summary: This study aims to understand the modal interactions between a rotating flexible member and a stationary element using a conceptual model. Theoretical and simplified models were developed, and eigenvalue and bifurcation analyses were performed to identify the participating modes. The results from the theoretical model were validated experimentally.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Article
Engineering, Civil
Sudip Chowdhury, Arnab Banerjee, Sondipon Adhikari
Summary: This paper studies the optimal design of inertial amplifier base isolators (IABI) for mitigating the dynamic response of multi-storey buildings under base excitations. The H-2 optimization method is used to obtain closed-form expressions for the optimal design parameters of IABI. The effectiveness of these expressions is evaluated by comparing the frequency and time domain responses of isolated structures to those of uncontrolled structures. The results show that the response reduction capacity of the optimal inertial amplifier base isolator is increased by 50% to 60% compared to traditional base isolators.
INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
(2023)
Article
Acoustics
Masoud Rezaei, Roohollah Talebitooti, Wei-Hsin Liao, Michael Friswell
Summary: This paper investigates the potential of a tuned mass damper (TMD) with an integrated piezoelectric layer for simultaneous energy harvesting and vibration suppression. A linear model is validated and analyzed to prepare for future studies on a nonlinear vibration absorber and energy harvester.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Mechanical
Sudip Chowdhury, Arnab Banerjee, Sondipon Adhikari
Summary: This paper introduces a method of combining negative stiffness devices with inerters to traditional base isolators and tuned mass dampers. The optimal design parameters of these novel passive vibration dampers are derived using H2 and H & INFIN; optimization methods. The results show that the optimized negative stiffness inerter-based base isolators and tuned mass dampers outperform traditional base isolators and tuned mass dampers in terms of dynamic response reduction capacity.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Mechanics
Mehmet Selim Akay, Alexander D. Shaw, Michael I. Friswell
Summary: Time simulation is commonly used to study the nonlinear response of rotating machines, but it is computationally inefficient and incomplete. Numerical continuation method can provide a more systematic and efficient way to explore the nonlinear behavior of such systems. This study demonstrates the use of numerical continuation method to transform the bifurcation diagram of a simpler nonlinearity to a more complex one in order to investigate rotor-stator contact responses in a more structured manner.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2023)
Article
Acoustics
Sudip Chowdhury, Arnab Banerjee, Sondipon Adhikari
Summary: This paper introduces the inertial amplifier viscoelastic tuned mass dampers (IAVTMD) and presents the mathematical formulations for optimal design parameters. The dynamic response reduction capacity of IAVTMD is significantly superior to conventional tuned mass dampers, with an improvement ranging from 20.87% to 26.47% for H-2 optimization and 15.48% for H-8 optimization. In addition, the optimized IAVTMD outperforms tuned mass damper inerters (TMDI) with improved dynamic response reduction capacity by 6.94% for H-2 optimization and 23.29% for H-8 optimization. The closed-form expressions for optimal design parameters are effective for practical applications.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Article
Engineering, Mechanical
Zhu Tianxu, Zhang Genbei, Zang Chaoping, Cui Haitao, M. I. Friswell
Summary: Model updating using multivalued responses is crucial for constructing strongly nonlinear models. Recently, fixed frequency tests have been used to measure fully multivalued responses, including both stable and unstable branches. However, transforming the measured responses to equivalent swept frequency tests can introduce errors in the updating process. This paper proposes a novel method for strong nonlinear model updating using the results of fixed frequency tests, which directly handles stable and unstable responses.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Mechanics
Sudip Chowdhury, Arnab Banerjee, Sondipon Adhikari
Summary: This article introduces the concepts of additional inerter-based viscoelastic mass dampers (AIVMD) and additional viscoelastic mass damper inerters (AVMDI). H-2 and H-infinity optimization schemes are used to derive the optimal closed-form solutions for these dampers analytically. A parametric study is conducted to investigate the sensitivity of the optimal design parameters with other system parameters. The results suggest that higher damper mass ratio, inerter mass ratio, and stiffness ratio are recommended for designing optimal novel dampers with robust vibration reduction capacities.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Engineering, Mechanical
Tanmoy Chatterjee, Danilo Karlicic, Milan Cajic, Sondipon Adhikari, Michael I. Friswell
Summary: This study investigates the dynamics of one-dimensional inerter-based quasiperiodic lattices and the effects of parametric uncertainty. Multiple edge states are found in the bulk spectrum of the system. The study also shows that parameter variations have significant effects on the Hofstadter-like butterfly, band gaps, edge states, and frequency responses. These findings are important for the design optimization of vibration absorbers and energy harvesters.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Civil
Moustafa S. Taima, Tamer A. El-Sayed, Michael I. Friswell
Summary: This study presents a novel approach to investigate the thermal lateral vibration of cracked nanobeams using Reddy beam analysis-based solutions. The effects of various factors on the natural frequencies are explored, and the outcomes are compared with prior findings, showing a strong level of agreement.
THIN-WALLED STRUCTURES
(2023)
Article
Chemistry, Physical
Saeid Saberi, Hamid Nasiri, Omid Ghorbani, Michael I. I. Friswell, Saullo G. P. Castro
Summary: In this study, the influence of material properties, geometrical dimensions, and environmental conditions on the characteristics of bistable composite laminates is investigated using the SHAP approach. The SHAP method is employed to explain the contribution and importance of input features on curvatures and snap-through force. The results highlight the significant impact of the transverse thermal expansion coefficient and moisture variation on the model's output for curvatures and snap-through force.
Article
Multidisciplinary Sciences
Moustafa S. Taima, Mohamed B. Shehab, Tamer A. El-Sayed, Michael I. Friswell
Summary: This study investigates the free vibration behavior of rotating beams made of functionally graded materials with tapered geometry and compares three different beam theories. The results indicate that the Third-order Shear Deformation Theory (TSDT) performs better in accurately predicting the natural frequencies of rotating, tapered beams composed of FGMs.
SCIENTIFIC REPORTS
(2023)
Proceedings Paper
Engineering, Mechanical
Nidhal Jamia, Hassan Jalali, Michael I. Friswell, Hamed Haddad Khodaparast, Javad Taghipour
Summary: In jointed structures, the behavior of the contact interfaces affects both the stiffness and damping properties. The contact surface quality and interface pressure distribution are among the parameters that determine the overall behavior of the contact interface. Small changes in these parameters can significantly alter the physics of the contact interface and introduce variability in structural dynamics properties. This highlights the need for robust models of the joint contact interface to predict their performance in the structure.
NONLINEAR STRUCTURES & SYSTEMS, VOL 1
(2023)
Proceedings Paper
Engineering, Mechanical
Marwan Sherri, Ilyes Boulkaibet, Tshilidzi Marwala, Michael I. Friswell
Summary: In this paper, a probabilistic-based evolution Markov chain algorithm is used to update finite element models. Bayesian approaches are well-known for quantifying uncertainties in structural systems and other engineering domains. The proposed algorithm combines the Metropolis-Hastings method with the Scuffled Complex Evolution strategy to approximate the posterior distribution function by generating new samples through a multi-chain procedure. The algorithm is applied to the Bayesian finite element model updating problem and compared with other MCMC samplers.
MODEL VALIDATION AND UNCERTAINTY QUANTIFICATION, VOL 3
(2023)
Proceedings Paper
Engineering, Mechanical
Javad Taghipour, Nidhal Jamia, Michael I. Friswell, Hamed Haddad Khodaparast, Hassan Jalali
Summary: Investigating the dynamics of jointed structures remains challenging, and modelling the dynamic behavior of bolted joint contact interfaces is particularly difficult. This study uses the alternating frequency-time approach to identify the nonlinear model of a bolted joint structure and measure its dynamic response through vibration tests.
NONLINEAR STRUCTURES & SYSTEMS, VOL 1
(2023)
Article
Engineering, Multidisciplinary
Tohya Kanahama, Motohiro Sato
Summary: This study theoretically explains the effect of initial deflection and initial slope on self-buckling characteristics of heavy columns and proposes a formula characterizing the self-buckling problem. The results show that the greatest height is proportional to the 2/3 power of radius, and the formula can potentially predict the height of tree-like natural structures.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2024)
Article
Engineering, Multidisciplinary
Aps Selvadurai, Alexander P. Suvorov
Summary: This paper examines the torsion of a solid cylinder made of a fluid-saturated porous medium with a hyperelastic porous skeleton. It analyzes the mechanics of the twisted cylinder in both short-term and long-term behaviors, using numerical solutions and the ABAQUSTM finite element code.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2024)
Article
Engineering, Multidisciplinary
S. Kanaun
Summary: This study focuses on spherical radially transverse isotropic heterogeneous inclusions in homogeneous isotropic conductive host media. The volume integral equation for the field in the medium with an isolated inclusion subjected to a constant external field is solved using Mellin-transform technique. The method allows revealing tensor structure of the solution with precision to one scalar function of radial coordinate. The study also investigates the influence of neutral inclusions and conductivity coefficients on the effective conductivity of the composite material.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2024)
Article
Engineering, Multidisciplinary
Marinos Kattis, Vassilis Tsitsos, Vassilis Karatzaferis
Summary: The proposed model utilizes continuum mechanics to describe the mechanical behavior of a weakened interface between materials with microstructure, simulating the weakened interface using a surface elastic medium adhering on either side with bulk elastic continua. The model is able to investigate the effect of a weakened interface on stress concentration around inhomogeneities embedded in an unbounded matrix of Cosserat materials.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2024)
Article
Engineering, Multidisciplinary
Shixiang Zhao, Yu. V. Petrov, Yuyi Zhang, G. A. Volkov, Zejian Xu, Fenglei Huang
Summary: This paper theoretically studies the thermal softening related to stress relaxation using the incubation time approach and examines the temperature-time correspondence. The developed relaxation model of plasticity (RP model) is analyzed and compared with other constitutive models and artificial neural networks. The advantages and disadvantages of different models are discussed, and the differences between the ANN model and other constitutive models are examined.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2024)
Article
Engineering, Multidisciplinary
Ivan I. Argatov, Federico J. Sabina
Summary: This study models a seismic metabarrier as a cluster of single-degree-of-freedom resonator units and considers the scattering effects on pulsed Rayleigh waves caused by the vertical displacements of the resonators and the normal contact forces. The variation of the amplitude reduction factor due to the model parameters variation is studied in detail.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2024)
