A study of the diffusion analogy technique for the photoelastic determination of transient thermal stresses

1988 ◽  
Vol 23 (1) ◽  
pp. 33-45
Author(s):  
P Stanley ◽  
Y J Yip
Keyword(s):  
Heat Conduction ◽  
Temperature Distribution ◽  
Isotropic Material ◽  
Heat Conduction Equation ◽  
Thermal Stresses ◽  
Conduction Equation ◽  
Formal Similarity ◽  
Photoelastic Study ◽  
Transient Thermal

The formal similarity between the equation governing the diffusion of a substance through a “porous” isotropic material and the heat conduction equation for the temperature distribution in an isotropic homogeneous solid is examined, and its use as a basis for the photoelastic study of transient thermal stresses is explored.

Inverse determination of thermal conductivity in lumber based on genetic algorithms

Holzforschung ◽  
2016 ◽  
Vol 70 (3) ◽  
pp. 235-241 ◽  
Author(s):  
Jingyao Zhao ◽  
Zongying Fu ◽  
Xiaoran Jia ◽  
Yingchun Cai
Keyword(s):  
Thermal Conductivity ◽  
Genetic Algorithms ◽  
Heat Conduction ◽  
Heat Conduction Equation ◽  
Convective Heat Transfer Coefficient ◽  
Conduction Equation ◽  
New Equation ◽  
Volume Method ◽  
Good Agreement

Abstract A 3D numerical solution of the heat conduction equation is proposed based on the finite volume method to describe the heating of wood, where the thermal conductivity (ThC) is variable, and the convective heat transfer coefficient is constant. ThC parameters were found through an optimization process based on genetic algorithms. The objective function between measured and simulated curves is determined, and parameters with greatest correspondence between measured and estimated values were obtained. As a result, a new equation for ThC is proposed, which depends on moisture and temperature. The proposed coefficient is validated by experiments, and a good agreement was found between experimental heating curves and those obtained by simulation by means of the new heat conduction equation.

scholarly journals Determination of temperature and thermal stresses distribution in power boiler elements with use inverse heat conduction method

2011 ◽  
Vol 32 (3) ◽  
pp. 191-200 ◽  
Author(s):  
sławomir Grądziel
Keyword(s):  
Boundary Condition ◽  
Heat Conduction ◽  
Temperature Distribution ◽  
Thermal Stresses ◽  
Thermal Boundary Condition ◽  
Transient Temperature ◽  
Inverse Heat Conduction ◽  
Transient Temperature Distribution ◽  
Power Boiler

Determination of temperature and thermal stresses distribution in power boiler elements with use inverse heat conduction method The following paper presents the method for solving one-dimensional inverse boundary heat conduction problems. The method is used to estimate the unknown thermal boundary condition on inner surface of a thick-walled Y-branch. Solution is based on measured temperature transients at two points inside the element's wall thickness. Y-branch is installed in a fresh steam pipeline in a power plant in Poland. Determination of an unknown boundary condition allows for the calculation of transient temperature distribution in the whole element. Next, stresses caused by non-uniform transient temperature distribution and by steam pressure inside a Y-branch are calculated using the finite element method. The proposed algorithm can be used for thermal-strength state monitoring in similar elements, when it is not possible to determine a 3-D thermal boundary condition. The calculated temperature and stress transients can be used for the calculation of element durability. More accurate temperature and stress monitoring will contribute to a substantial decrease of maximal stresses that occur during transient start-up and shut-down processes.

Heat Conduction in Deformed Initially Isotropic Materials

1963 ◽  
Vol 30 (4) ◽  
pp. 628-629
Author(s):  
G. C. Sih ◽  
G. F. Smith
Keyword(s):  
Heat Conduction ◽  
Temperature Distribution ◽  
Heat Flow ◽  
Isotropic Material ◽  
Circular Cylinders ◽  
Isotropic Materials ◽  
Fourier Heat Conduction

A generalization of the Fourier heat-conduction law appropriate for heat flow in a deformed incompressible initially isotropic material is considered and applied to the determination of the temperature distribution in a uniformly extended plate and in thick-walled circular cylinders subjected to torsion and shear.

Boundary Control of Temperature Distribution in a Spherical Shell With Spatially Varying Parameters

2011 ◽  
Vol 134 (1) ◽  
Author(s):  
Hossein Rastgoftar ◽  
Mohammad Eghtesad ◽  
Alireza Khayatian
Keyword(s):  
Heat Flux ◽  
Heat Conduction ◽  
Steady State ◽  
Temperature Distribution ◽  
Spherical Shell ◽  
Heat Conduction Equation ◽  
Conduction Equation ◽  
Order Partial Differential Equation ◽  
Lyapunov’S Theorem ◽  
Spatially Varying

This paper presents a solution to the control (stabilization) problem of temperature distribution in spherical shells with spatially varying properties. The desired temperature distribution satisfies the steady-state heat conduction equation. For the spherical shell under consideration, it is assumed that material properties such as thermal conductivity, density, and specific heat capacity may vary in radial, polar, and azimuthal directions of the spherical shell; the governing heat conduction equation of the shell is a second-order partial differential equation. Using Lyapunov’s theorem, it is shown how to obtain boundary heat flux required for producing a desired steady-state distribution of the temperature. Finally, numerical simulation is provided to verify the effectiveness of the proposed method such that by applying the boundary transient heat flux, in-domain distributed temperature converges to its desired steady-state temperature.

Sign in / Sign up

Export Citation Format

Share Document