Equivalent linearization technique in non-linear stochastic dynamics of a cable-mass system with time-varying lengthH. Weber, R. Iwankiewicz & S. Kaczmarczyk
In this paper the transverse vibrations of a vertical cable carrying a concentrated mass at its lower end and moving slowly vertically within the host structure are considered. It is assumed that longitudinal inertia of the cable can be neglected, with the longitudinal motion of the concentrated mass coupled with the lateral motion of the cable. An expansion of the lateral displacement of a cable in terms of approximating functions is used. The excitation acting...
Second-order two-temperature model of heat transfer processes in a thin metal film subjected to an ultrashort laser pulseE. Majchrzak & J. Dziatkiewicz
Thermal processes in domain of thin metal film subjected to an ultrashort laser pulse are considered. A mathematical description of the process discussed is based on the system of four equations. Two of them describe the electrons and lattice temperature, while third and fourth equations represent the generalized Fourier law, it means the dependencies between the electrons (lattice) heat flux and the electrons (lattice) temperature gradient. In the generalized Fourier law the heat fluxes are...
n-sided polygonal hybrid finite elements involving elementboundary integrals only for anisotropic thermal analysisR.F. Cao, X.J. Zhao, W.Q. Lin & H. Wang
As a combination of the traditional finite element method and boundary element method, the n-sided polygonal hybrid finite element method with fundamental solution kernels, named as HFS-FEM, is thoroughly studied in this work for two-dimensional heat conduction in fully anisotropic media. In this approach, the unknown temperature field within the polygon is represented by the linear combination of anisotropic fundamental solutions of problem to achieve the local satisfaction of the related governing equations, but not...
Results of numerical calculations of reinforced concrete (RC) beams are presented. Based on experimental results on longitudinally reinforced specimens of different sizes and shapes are investigated. Four different continuum constitutive laws with isotropic softening are used: one defined within continuum damage mechanics, an elasto-plastic with the Rankine criterion in tension and the Drucker–Prager criterion in compression, a formulation coupling elasto-plasticity and damage mechanics and the concrete damaged plasticity (CDP) model implemented in Abaqus. In a...
Two imperfectly bonded half-planes with an arbitrary inclusion subject to linear eigenstrains in anti-plane shearL.J. Sudak
An analytic solution to the anti-plane problem of an arbitrary inclusion within an elastic bimaterial under the premise of linear eigenstrains is developed. The bonding along the bimaterial interface is considered to be homogeneously imperfect. The boundary value problem is reduced to a single nonhomogeneous first order differential equation for an analytic function prescribed in the lower half-plane where the inclusion is located. The general solution is given in terms of the imperfect interface parameter...
The contour method is one of the promising techniques for the measurement of residual stresses in engineering components. In this method, the cut surfaces deform, owing to the relaxation of residual stresses. The deformations of the two cut surfaces are then measured and used to back calculate the 2-dimensional map of original residual stresses normal to the plane of the cut. Thus, it involves four main steps; specimen cutting, surface contour measurement, data analysis and...
Probabilistic solutions of a stretched beam discretized with finite difference scheme and excited by Kanai–Tajimi ground motionG.-K. Er, V. P. Iu & H.-E. Du
The probabilistic solutions of the elastic stretched beam are studied under the excitation of Kanai–Tajimi ground motion. Finite difference scheme is adopted to formulate the nonlinear multi-degree-of-freedom system about the random vibration of the beam. The state-space-split is employed to make the high-dimensional Fokker–Planck–Kolmogorov equation reduced to 4-dimensional Fokker–Planck–Kolmogorov equations which are solved by the exponential polynomial closure method for the probabilistic solutions of the system responses. The rules for selecting the state variables are...
Elastic hysteretic damping is defined as the dissipation of energy at a rate that is weakly dependent on frequency of vibration. In this article, we propose that the elastic hysteretic damping can be achieved by a simple modification to the viscous damping model. The proposed modification is based on computing an instantaneous correction factor that recursively depends on the state variables of the system. This correction factor is related to the rate by which the...
Static Stability Analysis of Mass Sensors Consisting of Hygro-Thermally Activated Graphene Sheets Using a Nonlocal Strain Gradient TheoryRajendran SELVAMANI, Madasamy MAHAVEER SREEJAYAN & Farzad EBRAHIMI
This paper develops a nonlocal strain gradient plate model for buckling analysis of graphene sheets under hygro-thermal environments with mass sensors. For a more accurate analysis of graphene sheets, the proposed theory contains two scale parameters related to the nonlocal and strain gradient effects. The graphene sheet is modeled via a two-variable shear deformation plate theory that does not need shear correction factors. Governing equations of a nonlocal strain gradient graphene sheet on the elastic...
Investigation on Machining Characteristics of Banana Fiber and Silicon Carbide Reinforced Polymer Matrix CompositesVenkatachalam GOPALAN, Vignesh PRAGASAM, Hitesh Byatarayanapura NARAYANASWAMY, Gokula Krishnan BALASUBRAMANIAN & Pandivelan CHINNAIYAN
In this study, machining characteristics of polymer composite consisting of banana fiber and silicon carbide (SiC) as reinforcements and epoxy resin as matrix are investigated. Reinforcement phases consist of raw banana fiber powder sieved to 100 microns size of 1% (w/w) and SiC powder of 1% (w/w). The conventional machining process is carried out on the fabricated composite samples by considering the depth of cut, feed rate and speed as influential parameters. The central composite...
The Effect of Strength Differential on Material Effort and Lifetime of Steam Turbine Rotors Under Thermo-Mechanical LoadMariusz BANASZKIEWICZ, Waldemar DUDDA & Janusz BADUR
The paper presents the results of experimental tests and numerical simulations related with the strength differential effect. Tensile and compression tests on 2CrMoV low-alloy steel are performed to evaluate the magnitude of the yield stress difference in tension and compression. The strength differential parameter is then used in the formula for equivalent stress proposed by Burzynski. The material effort calculated using Burzynski and Huber-Mises-Hencky hypotheses was compared for different start-stop cycles. Analytical notch stress-strain correction...
Research on Influence of TiSi(N) Reflective Coating Thermal Resistance on Energy Absorption of Fireproof Textile Coupled with Auxetic FabricDanuta MIEDZIŃSKA, Michał STANKIEWICZ, Roman GIELETA & Konstanty MARSZAŁEK
The research presented in the paper deals with the improvement of firemen protective clothing. The proposed modification of the special textile PROTON is based on the application of TiSi(N) nanocomposite reflective layer, which improves the thermal resistance of the coated material. The second improvement deals with the implementation of auxetic textile into the protective clothing structure. Such material is characterized with the very good blast wave resistance. In the paper both phenomena were studied. The...
Performance Evaluation and Frequency Response Analysis of a Two Stage Two Spool Electrohydraulic Servovalve with a Linearized ModelNitesh MONDAL & Biswanath DATTA
This article focuses on the performance study and frequency response analysis with the state space model of a linearized two stage two spool non-conventional electrohydraulic servovalve from a set of nonlinear state equations. The performance of this valve depends on many valve geometries and fluid parameters. This non-conventional electrohydraulic servovalve is controlled by a pressure controlled pilot, which generates a differential pressure between the upper and lower chambers of two spools. This differential pressure acts...
Poznań University of Technology7
Phetchabun Rajabhat University2
AGH University of Science and Technology2
Cracow University of Technology2
Vellore Institute of Technology University2
Silesian University of Technology2
University of Architecture, Civil Engineering and Geodesy2
An-Najah National University1