• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.105-105
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• 2003

• Advances in materials Research
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• v.6 no.1
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• pp.27-43
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• 2017

The transient thermo-mechanical behavior of a simply-supported beam made of a functionally graded material (FGM) under the effect of a moving heat source is investigated. The FGM consists of a ceramic part (on the top), which is the hot side of the beam as the heat source motion takes place along this side, and a metal part (in the bottom), which is considered the cold side. Grading is in the transverse direction, with the properties being temperature-dependent. The main steps of the thermo-elastic modeling included deriving the partial differential equations for the temperatures and deflections in time and space, transforming them into ordinary differential equations using Laplace transformation, and finally using the inverse Laplace transformation to find the solutions. The effects of different parameters on the thermo-mechanical behavior of the beam are investigated, such as the convection coefficient and the heat source intensity and speed. The results show that temperatures, and hence the deflections and stresses increase with less heat convection from the beam surface, higher heat source intensity and low speeds.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.125-130
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• 2001

Diagnosis or measurements using Infrared thermo-image hasn t been available. A quick diagnosis and thermal analysis can be possible when that kind of system is introduced to the investigation of each part. In this study, Infrared Camera, Thermo-vision 900 was used in order to investigate. Infrared Camera usually detects only Infrared wave from the light in order to illustrate the temperature distribution. Infrared diagnosis system can be applied to various field. Also, it is more effective to analyze temperature distribution on the machining center main-axis process.

• Journal of Mechanical Science and Technology
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• v.17 no.2
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• pp.171-180
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• 2003

One of the most significant problems in the processing of composite materials is residual stress. The high residual stress may cause cracking in the matrix without external loads and degrade the integrity of composite structures. In this study, thermo-viscoelastic residual stresses occurred in an aluminum liner-inserted polymer composite cylinder are investigated. This type of the structure is used for rocket fuselage due to the convenience to attach payloads and equipment to the metal liner by machining. The time and degree of cure dependent thermo-viscoelastic constitutive equations are developed and coupled with a thermo-chemical process model. These equations are solved with the finite element method to predict the residual stresses in the composite cylinder and also in the interface between the liner and the composite during cure.

• Solar Energy
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• v.18 no.2
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• pp.105-113
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• 1998

In general, the thermo-diode is a device designed to allow heat to be transferred only in one direction. However, the bidirectional thermo-diode devised to change the heat flow in the desired direction can be used for the reduction of the heating load in winter as well as the cooling load in summer. In this study, a solar heating system using loop-type bidirectional thermo-diodes is designed and set up, also it is successfully applied to an outdoor test cell for the verification of its usefulness.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03b
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• pp.261-264
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• 1999

An integrated finite element-based model is presented for the prediction of the three dimensional tran-sient thermo-mechanical behavior of the work roll in hot strip rolling. The model is comprised of basic finite element models which are incorporated into an iterative solution procedure to deal with the inter-dependence between the thermo-mechanical behavior of the strip and that of the work roll which arises from roll-strip contact as well as with the interdependence between the thermal and mechanical behav-ior Demonstrated is the capability of the model to reveal the detailed aspects of the thermo-mechanical behavior and to reflect the effect of various process parameters.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.6
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• pp.406-413
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• 1988

This paper is to investigate relationships between tree inception voltage, tree extension or treeing breakdown voltage and physical characteristics changing as parameter of the post-cured conditions of thermo-setting epoxy resin. According to the results in this paper, the optimal tree inception voltage and treeing breakdown voltage of the samples are obtained for the sample post cured for 15 hours at 100 'C. It can be noticed that these results are closely related with the state of interior molecule coupling and three-dimen sional cross-linked of thermo-setting epoxy resin. And tree inception, tree extension and treeing breakdown of the samples are affected significantly on the post-cured conditions and the cooling method after post-cured of thermo-setting epoxy resin. Moreover, the tree extension by ambient temperature are closely related with softening temperature of thermo-setting epoxy resin.

• Steel and Composite Structures
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• v.27 no.6
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• pp.761-775
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• 2018

In the present work, the recently developed non-polynomial shear deformation theories are assessed for thermo-mechanical response characteristics of laminated composite plates. The applicability and accuracy of these theories for static, buckling and free vibration responses were ascertained in the recent past by several authors. However, the assessment of these theories for thermo-mechanical analysis of the laminated composite structures is still to be ascertained. The response characteristics are investigated in linear and non-linear thermal gradient and also in the presence and absence of mechanical transverse loads. The laminated composite plates are modelled using recently developed six shear deformation theories involving different shear strain functions. The principle of virtual work is used to develop the governing system of equations. The Navier type closed form solution is adopted to yield the exact solution of the developed equation for simply supported cross ply laminated plates. The thermo-mechanical response characteristics due to these six different theories are obtained and compared with the existing results.

• Steel and Composite Structures
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• v.45 no.4
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• pp.535-546
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• 2022

The memory response of nonlocal systematical formulation size-dependent coupling of viscoelastic deformation and thermal fields for piezoelectric materials with dual-phase lag heat conduction law is constructed. The method of the matrix exponential, which constitutes the basis of the state-space approach of modern control theory, is applied to the non-dimensional equations. The resulting formulation together with the Laplace transform technique is applied to solve a problem of a semi-infinite piezoelectric rod subjected to a continuous heat flux with constant time rates. The inversion of the Laplace transforms is carried out using a numerical approach. Some comparisons of the impacts of nonlocal parameters and time-delay constants for various forms of kernel functions on thermal spreads and thermo-viscoelastic response are illustrated graphically.

• Advances in nano research
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• v.16 no.6
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• pp.601-613
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• 2024

A new analytical buckling solution of a thermo-electro-magneto-elastic (TEME) cylindrical nano-shell made of BiTiO₃-CoFe₂O₄ materials is obtained based on Hamiltonian approach. The Winkler and Pasternak elastic foundations as well as thermo-electro-magneto-mechanical loadings are applied, and two different types of edge conditions are taken into the investigation. According to nonlocal strain gradient theory (NSGT) and surface elasticity theory in conjunction with the Kirchhoff-Love theory, governing equations of the nano-shell are acquired, and the buckling bifurcation condition is obtained by adopting the Navier's method. The detailed parameter study is conducted to investigate the effects of axial and circumferential wave numbers, scale parameters, elastic foundations, edge conditions and thermo-electro-magnetic loadings on the buckling behavior of the nano-shell. The proposed model can be applied in design and analysis of TEME nano components with multi-field coupled behavior, multiple edge conditions and scale effect.