91 research outputs found
A Constitutive Formulation for the Linear Thermoelastic Behavior of Arbitrary Fiber-Reinforced Composites
Get PDFThe linear thermoelastic behavior of a composite material reinforced by two independent and inextensible fiber families has been analyzed theoretically. The composite material is assumed to be anisotropic, compressible, dependent on temperature gradient, and showing linear elastic behavior. Basic principles and axioms of modern continuum mechanics and equations belonging to kinematics and deformation geometries of fibers have provided guidance and have been determining in the process of this study. The matrix material is supposed to be made of elastic material involving an artificial anisotropy due to fibers reinforcing by arbitrary distributions. As a result of thermodynamic constraints, it has been determined that the free energy function is dependent on a symmetric tensor and two vectors whereas the heat flux vector function is dependent on a symmetric tensor and three vectors. The free energy and heat flux vector functions have been represented by a power series expansion, and the type and the number of terms taken into consideration in this series expansion have determined the linearity of the medium. The linear constitutive equations of the stress and heat flux vector are substituted in the Cauchy equation of motion and in the equation of conservation of energy to obtain the field equations.</jats:p
On Magneto-Viscoelastic Behavior of Fiber-Reinforced Composite Materials Part I: Anisotropie Matrix Material
No full textOn Magneto-Viscoelastic Behavior of Fiber-Reinforced Composite Materials Part - II: Isotropic Matrix Material
No full textA Continuum Formulation for Fiber-Reinforced Viscoelastic Composite Materials With Microstructure PART - I: ANISOTROPIC MATRIX MATERIAL
No full textA Mathematical Model for Thermomechanical Behavior of Arbitrary Fiber Reinforced Viscoelastic Composites - II
No full textDynamic Analysis of a Piezoelectric Motor in ANSYS
Get PDFBu çalışmada model olarak, lineer bir ultrasonik motor tipi olan Piezolegs-LL1011A piezoelektrik motor
seçilmiştir. Bu motorun modellemesi yapıldıktan sonra modal ve harmonik analizleri sonlu elemanlar
paket programı olan ANSYS ile çözdürülmüştür. Yapılan bu analizler neticesinde Piezolegs motora ait
modal frekans değerleri elde edilmiştir. Elde edilen bu modal frekans sonuçlarından harmonik analizde
kullanılabilecek ve sürücü ucun rotor hareketini sağlayacak en uygun frekans aralığı tayin edilmiştir.
Piezolegs motora uygulanan yükler doğrultusunda harmonik analizi yapılarak elde edilen frekanslara
göre motordaki sürücü uç hareketleri gözlemlenmiştir.In this study, Piezolegs-LL1011A which is linear piezoelectric motor type has been selected as a model.
After modelling has been done of this motor, modal and harmonic analysis of same motor have been
obtained with finite element package program ANSYS. As a result of these analysis, natural frequency
values have been obtained of Piezolegs motor. An appropriate frequency range for motion of drive tip is
obtained for harmonic analysis. In according to applied forces, harmonic analysis is done and drive tip
motion of motor is observed
The Effects of Shear on the Deflection of Simply Supported Composite Beam Loaded Linearly
No full textA Mathematical Model for Thermomechanical Behavior of Arbitrary Fiber Reinforced Viscoelastic Composites - I
No full textHegzagonal Simetriye Sahip Viskoelastik Fiber-takviyeli Piezoelektrik Ortamlar İçin Matematiksel Bir Model
Get PDFKonferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2008Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2008Bu çalışma, fiber takviyeli viskoelastik ve piezoelektrik özellikler taşıyan ortamların elektrotermomekanik davranışlarını temsil eden bünye denklemlerine ait matematiksel bir modelin oluşturulması amacını taşımaktadır. Biyolojik doku ve yapı elemanları bu matematiksel modelde bahsedilen özellik ve davranışları tamamen veya kısmen bünyesinde bulundurmaktadır. Modern sürekli ortamlar mekaniğinin temel ilke ve aksiyomları, bu çalışmanın gerçekleştirilmesinde yol gösterici ve belirleyici olmuştur. Ele alınan malzemenin matris kısmı viskoelastik ve piezoelektrik anizotropiye sahip olup buna ilave olarak fiber takviyesi nedeniyle de malzeme tüm ortam olarak anizotropik bir yapıya sahip olacaktır. Bu bağlamda cisim davranış olarak kendisini elastik gerilme, disipatif gerilme, ve elektriksel polarizasyon alanları tarzında ifade etmektedir. Elde edilen bünye denklemlerinden, elastik gerilmenin ve polarizasyonun, işlemler içinde tanımlanan bir termodinamik potansiyelden türetildiği, dissipatif gerilme ise kendi argümanlarına bağlı tansörel bir fonksiyon olarak ortaya çıktığı görülmüştür. Gerilme potansiyeli ve dissipatif gerilme fonksiyonları bağlı oldukları argümanlarına göre bir kuvvet serisi ile temsil edilerek bünye denklemleri ortaya konulmuştur.Main objective of this study is construct a mathematical model belong to constitutive equations which represent electro-themomechanical behavior of viscoelastic and piezoelectric media, where the material was brought to a composite state by fiber reinforcing. Physical properties and behaviours mentioned in this mathematical model have been comprised wholly or partially in the biological tissue elements. Fundamental principles and axioms of modern Continuum Mechanics have been used as a guide. In addition to the strong anisotropy being caused by distribution of fibers in an otherwise isotropic material, we have assumed here that the matrix material is also by itself anisotropic with piezoelectric property. In this context the material will respond by means of elastic stress, dissipative stress and electric polarization as relevant constitutive response functions. In this general approach elastic stress and polarization is derived from a thermodynamic potential (elastic stress potential), while dissipative stres is expressed as a tensorial function in terms of its relevant arguments. After necessary information was obtained on the constitutive functions, power series expansions were made based on the assumption that such functions are analytic
A Mathematical Model for the Electrothermomechanical Mechanical Behavior of Viscoelastic Piezoelectric Body having Hexagonal Symmetry
No full text- …
