During actual motion, there are inevitably clearances between the motion pairs of the mechanism, and the clearances will have a large impact on stability of the mechanism. Previous studies mainly focused on the dynamic response of simple mechanisms with single clearance and less on chaos. Even if chaos is studied, it mainly focused on the chaos of mechanisms and less on the chaos of clearance joints;

In this paper, a modified variational method is developed to study the free and forced vibration of coupled straight–curved beam systems with an arbitrary number of eccentric discontinuities (EDs). Based on the generalized shell theory, the kinetic and potential functional of the curved beam with arbitrary subtended angles is formulated. Since the shear and inertial (or radial–tangential–rotational

The thickness mistuning of coatings and blisks cannot be predicted before manufacturing process, and the mistuning patterns normally tend to be random, which has not been investigated in opened studies. A novel finite element model (FEM) is developed to incorporate variable thicknesses of the coatings and the blisks. The FEM requires only the sector-level node coordinates of the uncoated blisks and

A higher-order shear deformation theory is utilized to discuss the vibration of a laminated composite plate containing four magnetostrictive layers based on Pasternak’s foundations in the current article. Hamilton’s principle is used to derive the governing dynamic equations related to the vibration of present smart structure under velocity feedback control with constant gain distributed. Navier’s

Reed-type valve is widely used in refrigeration compressor; its dynamic performance directly affects the energy efficiency of compressors. In order to reveal the motion law of the reed-type valve of refrigeration compressor, a dynamic model based on vibration theory is established. According to the actual movement characteristics of the reed valve, the motion process of the reed is divided into two

In order to acquire efficient algorithms for complicated problems in structural dynamics, an improved integration algorithm with controllable numerical dissipation is developed based on a two-step explicit acceleration integration method. The improved method is a step-by-step integration scheme which is conditionally stable and robust in strongly nonlinear systems. The consistency, accuracy and the

Vibration suppression for marine structures has been an important concern for a long time. In this paper, a specifically designed continuous module that consists of an Euler beam, a preloaded bimorph beam and a coupled spring unit produces self-increasing damping and strongly suppresses the steady-state response near resonance. Based on Hamilton’s principle, we derive a two-degree-of-freedom coupled

The problem of estimating the time variant reliability of randomly parametered dynamical systems subjected to random process excitations is considered. Two methods, based on Monte Carlo simulations, are proposed to tackle this problem. In both the methods, the target probability of failure is determined based on a two-step approach. In the first step, the failure probability conditional on the random

Fluidelastic instability of a tube array is extremely important to the security of a nuclear power plant. Lots of experimental analyses were conducted on the fluidelastic instability of a tube array subjected to two-phase flow in the transverse direction. Streamwise fluid-elastic instability of a tube array has been ignored for a long time until recently observations of streamwise tube failure in a

Bounding surface plasticity has been widely used for capturing the stress–strain behaviour of geomaterials. However, it may require multiple sets of model parameters for constitutive modelling of sands with a wide range of initial states, because of the distinct critical state characteristics under low and high densities or pressures in the \(e-\ln {p}'\) plane. In this study, an enhanced bounding

The objective of this contribution is the numerical investigation of growth-induced instabilities of an elastic film on a microstructured soft substrate. A nonlinear multiscale simulation framework is developed based on the FE2 method, and numerical results are compared against simplified analytical approaches, which are also derived. Living tissues like brain, skin, and airways are often bilayered

Due to the large surface/interface-to-volume ratio, surface/interface effect in nanomaterials begins to play an important role in changing the constitutive law seen in classical elasticity theory. This work investigates the size-dependent elastic field of nano-inhomogeneity due to interface and interphase effect, respectively. Closed-form solution to the elastic field of nano-inhomogeneity with interface

Based on the Hamilton’s principle, a nonlinear mathematical model of the cantilever-type piezoelectric energy harvester with a tip mass is systematically derived under parametric and external excitations. The proposed model accounts for geometric and electro-mechanical coupling nonlinearities, damping nonlinearity and the inextensibility condition of beam. Using the Galerkin approach, the proposed

The problem of vibrations generated in a homogeneous and isotropic elastic half-space by spatially concentrated forces, known in Seismology as (part of) the Lamb problem, is formulated here in terms of Helmholtz potentials of the elastic displacement. The method is based on time Fourier transforms, spatial Fourier transforms with respect to the coordinates parallel to the surface (in-plane Fourier

In this paper, we investigate the problem for a classical piezoelectric vibration energy harvester. Exact theoretical solution to the problem is derived and compared to the solutions proposed in the literature. Asymptotic expansions of the solution are explored in the hope of finding a plausible simpler approximation of the solution and corresponding output performance measures. Dependence of the output

In this paper, we examine the transient response of two bonded dissimilar functionally graded magneto-electro-elastic (MEE) layers with multiple interfacial cracks under magneto-electro-mechanical impacts. Material properties of the MEE layers are assumed to vary exponentially in the thickness direction of the layers. However, the rate of material properties gradation are different. First, the analytical

This article investigates size-dependent nonlinear dynamic modeling and vibration analysis of nanomechanical resonators equipped with piezoelectric layers employing perturbation methods. For nonlinear dynamic modeling, the nanomechanical beam resonator is modeled based on the nonlocal elasticity theory and von-kármán type of nonlinear formulation. Then, the Hamilton’s principle is employed to derive

We obtain here a new fundamental solution for the harmonic vibration of asymmetric, laminated, anisotropic plates. The fundamental solution is derived via the Fourier transform and its final form is given in terms of definite integrals, which are evaluated numerically. Moreover, we present some of the higher order derivatives of the solution and their explicit spatial singularities, which are necessary

In this paper, the localized method of approximate particular solutions using polynomial basis functions is proposed to solve plate bending problems with complex domains. The closed-form particular solutions of fourth-order differential equations can be reduced to the linear combination of the particular solutions of Helmholtz and modified Helmholtz equations. To alleviate the difficulty of solving

All the previous studies on the cavity flow are confined to either the study of its 2D or its 3D configuration in isolation. In this study, we endeavour to gain some physical insight into the corner vortices from the perspective of the flow topology in the 2D vis a vis 3D driven cavity by employing some recent developments in the field of topological fluid dynamics. The computed flow is post-processed

This paper presents a quasi-static model of high-speed ball bearing, and the analytical expressions of dynamic stiffness are obtained. The action mechanism of centrifugal force and gyroscopic moment and its effect on kinematic and mechanical characteristics of bearing are studied. Results show that with the increase in rotational speed, centrifugal force increases continuously, while gyroscopic moment

The purpose of this paper is to provide a high-order finite element method (FEM) formulation of nonlocal nonlinear nonlocal graded Timoshenko based on the weak form quadrature element method (WQEM). This formulation offers the advantages and flexibility of the FEM without its limiting low-order accuracy. The nanobeam theory accounts for the von Kármán geometric nonlinearity in addition to Eringen’s

A new approach of coupling multibody dynamics and fluid dynamics is developed to model hydrodynamic lubrication of spherical clearance joints with thin fluid film and relative multidirectional motion. The model accounts for dynamics motion of articulating components as well as both squeeze- and wedge-film actions of the synovial fluid. Multibody dynamics methodology is employed to derive the motion

Free vibration response of a joined shell system including cylindrical and spherical shells is analyzed in this research. It is assumed that the system of joined shell is made from a functionally graded material (FGM). Properties of the shells are assumed to be graded through the thickness. Both shells are unified in thickness. To capture the effects of through-the-thickness shear deformations and

This paper investigates the frictional receding contact problem between a functionally graded (FG) layer resting on a homogeneous coated half-plane when the system indented by a rigid cylindrical punch. The shear modulus of the upper graded layer is assumed to vary exponentially in the depth direction. Upon loading, the advancing contact and receding contact occur between the FG layer and rigid punch

In the present study, a continuous-based thermo-electromechanic model has been developed by the Kirchhoff plate’s theory and the modified flexoelectric theory in order to study the size-dependent nonlinear free vibration of functionally graded flexoelectric nano-plate under the magnetic field. Using the Hamilton’s principle and variation method, the nonlinear governing differential equations of the

In this paper, a new analytical approach suitable for the stability analysis of multibody mechanical systems is introduced in the framework of Lagrangian mechanics. The approach developed in this work is based on the direct linearization of the index-three form of the differential-algebraic dynamic equations that describe the motion of mechanical systems subjected to nonlinear constraints. One of the

The solution to the classic so-called Couplet’s problem was provided more than a century ago, and recently, in the frame of limit equilibrium analysis, elliptical and pointed arches have also been carried out. Albeit triangular form of arches is the structural precursor of the mentioned ones, its mechanical behaviour has not been sufficiently researched. Therefore, the present paper elaborates in detail

Nonlinear flexural vibrations of rectangular atomic force microscope cantilever have been investigated by both the theoretical model and experimental works. As for the theoretical model, the Timoshenko beam theory which takes the rotatory inertia and shear deformation effects into consideration has been adopted. To increase the accuracy of the theoretical model, all necessary details for cantilever

The present paper studies the anti-plane shear motion of an inhomogeneous elastic five-layered plate amidst the four contrasting material setups. The asymptotic analysis method in regard to the various material parameters is adopted for the study. The respective displacements, stresses and the Rayleigh-Lamb dispersion relation corresponding to the antisymmetric anti-plane motion with perfect interlayer

Nano-sized batteries composed of nanostructured electrode materials stand as one of the most promising candidates for next-generation rechargeable charging devices which have been widely used in the energy storage systems for advanced power applications. Buckling analysis of nanobeam under non-uniform concentration is significantly important for the design of nano-sized batteries under the rapid charging

In this paper, the buckling and free vibration of a Mindlin plate with a side crack are presented considering a uniaxial in-plane compressive or tensile load. The side crack is through the thickness of the plate. In the Ritz method, a series of corner functions are incorporated into the admissible functions which consist of the modified characteristic functions. With this treatment, one can describe

This article presents the free vibration frequencies of composite plates reinforced with single-walled carbon nanotubes by using a refined simplified two-variable nth-higher-order theory. Four kinds of distribution of uniaxially aligned reinforcement material are presented. The most famous one is the uniform; in addition, three types of functionally graded distributions of carbon nanotubes in the through-thickness

The trajectory of a ball impacting with an angle on a rigid boundary is recorded with a high-speed camera and the dynamics is reconstructed in a computer. Several experiments are carried out in order to obtain statistical distributions of the trajectory. On the other hand, a continuum model of a viscoelastic material ball simulates the experiment. If the values of the constitutive parameters (e.g.

In this contribution, a constitutive model is proposed for filled rubber-like materials to describe hysteresis. The model is based on the network decomposition concept. Rubber matrix is decomposed into purely elastic and deformable networks. The Gent model is considered to model the purely elastic network. The deformable network is simulated by using the freely jointed chain concept, a probability

An efficient and nonlinear form-finding method is proposed for symmetric cable–strut structures with complex geometry or many nodes. Expressed in the symmetry-adapted coordinate system, the first block matrix of the symmetry-adapted tangent stiffness matrix is extracted using the full symmetry subspace, which is much smaller-sized and associated with the first irreducible representation of a symmetry

This paper focuses on the effects of the boundary wall thickness and the velocity power index parameters on a steady 2D mixed convection flow along a vertical semi-infinite moving plate with non-uniform thickness. The effects of diffusion on the velocity, temperature and concentration fields with power-law temperature and concentration distributions at the plate surface are also analyzed. A shooting

Instead of the traditional method of utilizing the extremal values of Rayleigh quotient, in this research we develop an upper bound theory to determine the natural frequencies in a linear space of boundary functions. The boundary function will have the following restrictions: boundary conditions are satisfied, fourth-order polynomial at least with unit leading coefficient. It proves that the maximum

Precise prediction of collapse pressure is a key role in structural integrity assessment of piping systems. The present study uses an \(\hbox {Al}{-}\hbox {Al}_{\mathrm {2}}\hbox {Cu}\) functionally graded (FG) pipe fabricated through horizontal centrifugal casting technique to empirically investigate its mechanical responses under hydrostatic pressure test. The evolutions of deformations correspond

This work proposes a new constitutive model that takes into account the asymmetry of Ti–6Al–4V, its microstructural state and its pronounced anisotropy in order to improve the use of this titanium alloy in biomechanics and aeronautics in particular. The choice of the stress directions and their effect on shaping procedures in light of accounting the effect of heat treatment on the behavior of Ti–6Al–4V

High-Q micromechanical resonators have been studied intensively because of the tunable performance and the associated potential applications. Nevertheless, some designs experience long relaxation times which hinder fast switching applications. We investigate an open-loop control, an intentional and confined time-periodic variation, that is capable of reducing the transient time allowing rapid switching

The paper presents a new method for the identification of joint friction, reductor self-locking and gear backlash parameters. The method was developed using an existing hexapod robot. During the process, the motor driving currents given by the model and measured on the real device were observed and compared. Initially, the current curves showed specific differences. After the analysis of these deviations

A new linear yield criterion in terms of principal stresses is developed for the purpose of overcoming the analytical difficulty of mechanical parameters when using the nonlinear Mises yield criterion. This developed yield criterion is established through the parabola interpolation method and the mathematical averaging method, which can be called as the mean influence factor yield criterion, or called

This paper presents a simple and effective analytical approach to investigate buckling behavior of carbon nanotube-reinforced composite (CNTRC) cylindrical shells and toroidal shell segments surrounded by elastic media and subjected to elevated temperature, lateral pressure and thermomechanical load. The properties of constituents are assumed to be temperature-dependent, and effective properties of

The purpose of this article is to develop a class of universal relations for an incompressible isotropic electro-magneto-elastic (hereafter EME) material in order to generalize the continuum concept to electro-magneto-elasticity. In line with that, we adopt an electro-magneto-elasticity theory following the second law of thermodynamics-based approach. More precisely, we first extend a thermodynamically

In this paper, the precise deployment dynamical behavior is studied for a planetary rover mast mechanism of spacecraft undergoing large attitude adjustment motion. In the conventional dynamic formulation, flexible appendages of mast attached to spacecraft are taken as linear deformations with isotropic material, and it can result in improper responses. Therefore, the present model takes into account

Bifurcation analysis of the nonlinear vibration of an inextensible cantilever beam is analyzed by using the nonlinear normal mode concept. Two flexural modes of the cantilever beam, one in each transverse plane is considered. Two degrees-of-freedom nonlinear model for the vibration in the transverse direction is obtained by the discretization of the governing equation using Galerkins method based on

The significance of velocity second slip model of non-Newtonian fluid on peristaltic pumping in existence of double-diffusivity convection in nanofluids and induced magnetic field is deliberated. Mathematical modelling of current problem is defined in fixed frame of reference and then abridges under well- known conjecture of long wavelength and low but finite Reynolds number approximation. Precise

The self-adaptive behavior of a clamped–clamped beam with an attached slider has been experimentally demonstrated by several research groups. In a wide range of excitation frequencies, the system shows its signature move: The slider first slowly moves away from the beam’s center, at a certain point the vibrations jump to a high level, then the slider slowly moves back toward the center and stops at

Electric trains rely on the pantograph and the overhead catenary system (OCS) to receive energy from the power main lines. The purpose of this article is to elaborate on the simulation of pantograph and catenary dynamic interaction. The main feature of this method is using a fast analytical approach in order to simulate the entire catenary and to avoid using the finite elements method. This method

Operational modal analysis (OMA) methods are frequently applied for obtaining information on structural dynamic parameters, such as natural frequencies and mode shapes. While synchronization between acceleration response data sets used in OMA is not a prerequisite for estimating natural frequencies, synchronization discrepancies may lead to non-negligible errors in the estimation of mode shapes. Synchronization

We present a numerical and experimental study on the static-divergence instability of an inverted cantilevered plate in an uniform axial subsonic airflow. The flow is assumed ideal and is confined by a rigid channel wall. The inverted cantilevered plate, unlike a conventional one, is with a clamped trailing edge and a free leading edge. The equation of the plate motion is solved by the finite-difference

A two-dimensional (2-D) elasticity solution is developed to investigate the time-dependent response of laminated functionally graded beam with viscoelastic interlayer. The elastic modulus in each functionally graded layer varies through the thickness following an exponential function, and the mechanical property of each layer is described by the exact 2-D elasticity equations. Viscoelastic property

This paper studies analytically the problem of the sudden failure of a number of stays through a suitable mathematical model, based on the analytical method exposed by authors in previous publications and extended in this study through a 3D analysis. The analysis is carried out by the modal superposition method, and the gathered equations of the problem are solved through the Galerkin procedure and

Studied in this paper is the surface tension-induced stress field around two nanoscale holes in an infinite, elastic matrix. The complex variable method is adopted to describe the assumed plane-strain deformation of the structure. The stress boundary conditions at the surfaces of the holes are formulated via the integral-type Gurtin–Murdoch model. The stress field is finally obtained with the aid of

The present paper takes up the underlying nonlinear initial value problem from a preceding author’s work about the dynamics of a single bubble in a highly viscous liquid medium under different pressure impacts. The arising ordinary differential equation is mainly based on the constitutive relation of a second-order liquid that in particular includes two non-Newtonian material constants. In this article

In recent years to overcome many limitations of drilling operations, composite drill strings as high-tech rotors with complex dynamic behavior are under development. In this research, the fully coupled nonlinear vibration of composite drill strings, which consist of orthotropic layers, is investigated using the Lagrangian approach and the finite element method. In addition to the main nonlinear terms

We consider the linear thermo-piezoelectric properties of a ceramic matrix with cylindrical empty pores distributed periodically. The asymptotic homogenization method is applied to an elliptical tensor-weighted boundary value problem in the Stress-Charge-Entropy formulation of the constitutive relations with rapidly oscillating coefficients and free boundary conditions on the surfaces of the pores

Vibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing and also to investigate the materials mechanical properties. The fluid medium surrounding the nanostructure is typically modeled as a Newtonian fluid. A novel approach based on the exact theory has been developed in this paper, to accurately predict the various vibration

A Legendre polynomial-based stochastic micromechanical framework is proposed to quantify the unbiased probabilistic behavior for the unsaturated concrete repaired by the electrochemical deposition method (EDM). By following the authors’ previous works, a deterministic micromechanical model with new multilevel homogenization scheme for the repaired unsaturated concrete is presented based on the material’s