Determination of the heat conductivity of thermally insulated materials by the method of estimating the integrated temperature

1989 ◽  
Vol 32 (5) ◽  
pp. 454-456
Author(s):  
E. A. Belov ◽  
E. S. Platunov ◽  
G. Ya. Sokolov
Keyword(s):  
Heat Conductivity

Determination of heat conductivity of waste glass feed and its applicability for modeling the batch-to-glass conversion

2017 ◽  
Vol 100 (11) ◽  
pp. 5096-5106 ◽  
Author(s):  
Miroslava Hujova ◽  
Richard Pokorny ◽  
Jaroslav Klouzek ◽  
Derek R. Dixon ◽  
Derek A. Cutforth ◽  
...  
Keyword(s):  
Heat Conductivity ◽  
Waste Glass

Numerical Modeling of Heat and Mass Transport with Inner Heat Exchange in Unsaturated Porous Media

2020 ◽  
Vol 27 ◽  
pp. 166-176
Author(s):  
Jozef Kačur ◽  
Patrik Mihala
Keyword(s):  
Mathematical Model ◽  
Porous Media ◽  
Heat Exchange ◽  
Inverse Problems ◽  
Water Transport ◽  
Heat Conductivity ◽  
Unsaturated Porous Media ◽  
Heat Transmission ◽  
Matrix Heat

We are focused to the numerical modelling of heat, contaminant and water transport in unsaturated porous media in 3D. The heat exchange between water and porous media matrix is taken into the account. The determination of heat energy transmission coefficient and matrix heat conductivity is solved by means of inverse problem methods. The mathematical model represents the conservation of heat, contaminant and water mass balance. It is expressed by coupled non-linear system of parabolic-elliptic equations. Mathematical model for water transport in unsaturated porous media is represented by Richard's type equation. Heat transport by water includes water flux, molecular diffusion and dispersion. A successful experiment scenario is suggested to determine the required parameters including heat transmission and matrix heat conductivity coefficients. Additionally we investigate contaminant transport with heat transmission and contaminant adsorption. The obtained experiments support our method suitable for solution of direct and inverse problems. This problem we have discussed previously in 1D model, but preferential streamlines in 1D thin tubes shadow accurate results in determination of required parameters. In our presented setting we consider a cylindrical sample which is suitable in laboratory experiments for inverse problems.

Determination of the nonlinear heat-conductivity coefficient of tubular bodies by the method of functional identification

2006 ◽  
Vol 79 (6) ◽  
pp. 1070-1077
Author(s):  
V. T. Borukhov ◽  
V. I. Timoshpol’skii ◽  
G. M. Zayats ◽  
E. V. Kalinevich ◽  
V. A. Tsurko
Keyword(s):  
Heat Conductivity ◽  
Heat Conductivity Coefficient ◽  
Functional Identification ◽  
Tubular Bodies

Determination of Temperature-Dependent Heat Conductivity and Thermal Diffusivity of Waste Glass Melter Feed

2013 ◽  
Vol 96 (6) ◽  
pp. 1891-1898 ◽  
Author(s):  
Richard Pokorny ◽  
Jarrett A. Rice ◽  
Michael J. Schweiger ◽  
Pavel Hrma
Keyword(s):  
Thermal Diffusivity ◽  
Heat Conductivity ◽  
Waste Glass ◽  
Temperature Dependent ◽  
Glass Melter

scholarly journals The heat insulating properties of potato starch extruded with addition of chosen by- products of food industry

2014 ◽  
Vol 16 (4) ◽  
pp. 28-32 ◽  
Author(s):  
Ewa Zdybel ◽  
Ewa Tomaszewska-Ciosk ◽  
Gabriela Główczyńska ◽  
Wioletta Drożdż
Keyword(s):  
Heat Conductivity ◽  
Food Industry ◽  
Potato Starch ◽  
Raw Material ◽  
Insulating Materials ◽  
Potato Pulp ◽  
Insulating Properties ◽  
Heat Transition ◽  
By Products

Abstract The study was aimed at determination of time of heat transition through the layer of quince, apple, linen, rose pomace and potato pulp, as well as layer of potato starch and potato starch extruded with addition of above mentioned by-products. Additionally the attempt of creation a heat insulating barrier from researched raw material was made. The heat conductivity of researched materials was dependent on the type of material and its humidity. Extruded potato starch is characterized by smaller heat conductivity than potato starch extruded with addition of pomace. The obtained rigid extruded starch moulders were characterized by higher heat insulating properties than the loose beads. It is possible to use starch and by-products of food industry for production of heat insulating materials.

scholarly journals Reverse Task of Heat Conductivity for the Semilimited Bar

2019 ◽  
pp. 27-31
Author(s):  
O. Shevchenko
Keyword(s):  
Thermal Conductivity ◽  
Inverse Problem ◽  
Heat Exchange ◽  
Boundary Conditions ◽  
Heat Conductivity ◽  
Algebraic Equations ◽  
Newton's Law ◽  
Newton’S Law ◽  
Solid Bodies

The article concerns methods and formulas for the calculation of the coefficient of thermal conductivity of solid bodies using the known solutions of direct thermal conductivity tasks. The solution to the inverse problem of heat conductivity is based on the quite complicated methods including both hyperbolic functions and finite-difference methods. Under certain experimental conditions, the task is simplified at the regular thermal modes of 1, 2, or 3 types. Thus final formulas are simplified to algebraic equations. The simplification of the inverse problem of heat conductivity to algebraic equations is possible using other approaches. These me­thods are based on the analysis of the reference points, zero values of temperature distribution function, function inflection points, and its first and second derivatives. Here, we present formulas for the calculations of the temperature field on the assumption of the direct task solution for the half-bounded bar under the pulsed heating followed the re-definition of the boundary conditions. The article describes two methods in which solutions are reduced to simple algebraic formulas when using the specified points on hea­ting thermograms of test examples. These solutions allow algebraic deriving of simple relations for inverse problems of determination of thermophysical characteristics of solid bodies. The calculation formulas are given for the determination of the heat conductivity coefficient determination by two methods: by value of temperature, coordinate, and two moments at which this temperature is reached. The second method uses the values of two coordinates of the test sample in two different points where the equal temperature is reached at different points in time. The final solution of the equation is logarithmic. The analysis of known methods and techniques shows that experimental methods are oriented on the technical implementation and based on facilities of available equipment and instruments. Existing experimental techniques are based on specific constructions of measuring facilities. Simultaneously, there are well-studied methods of solution of thermal conductivity standard tasks set out in fundamental issues. The theoretical methods come from axioms, equations, and theoretical postulates, and they give the solution of inverse tasks of thermal conductivity. This work uses the solutions of direct tasks presented in the monograph by A.V.Lykov “The theory of heat conductivity”. These solutions have a good theoretical background and experts’ credit. The boundary conditions of the problem are next: the half-bounded thin bar is given. The side surface of the bar has a thermal insulation. At the initial moment, the instant heat source acts on the bar in its section at some distance from its end. Heat exchange occurs between the environment and the end of the bar according to Newton’s law. The initial (relative) temperature of the bar is accepted equal to zero. The heat exchange between the free end face of the bar and the environment is gone according to Newton’s law.

Determination of Thermo-Physical Properties of Rubber and its Effect on Curing Temperature Field of Tire

2011 ◽  
Vol 221 ◽  
pp. 533-539 ◽  
Author(s):  
Qing Ling Li ◽  
Lian Cui Fan ◽  
Tao Li
Keyword(s):  
Temperature Field ◽  
Physical Properties ◽  
Specific Heat ◽  
Heat Conductivity ◽  
Curing Temperature ◽  
Tire Rubber ◽  
Finite Element Software ◽  
Thermo Physical Properties ◽  
Different Parts

The main purpose of this paper was to determine the thermo-physical properties in different parts of tire rubber and analyze the influence of the thermo-physical properties with temperature variation on the curing temperature field of tire. Thermo-physical properties in different parts of tire rubber were measured by NanoflashTM in the curing process, the relation curve of thermo-physical properties on temperature was obtained, and the linear relations of heat conductivity and specific heat of rubber on temperature were obtained by the regression analysis. Using the finite element software to build a two-dimensional model of the tires, and curing temperature field distribution was predicted by simulating the tire vulcanization process .The temperature distribution and variation curve of temperature measuring points were obtained in the cueing process. The analysis result indicates that the thermo-physical properties have a significant impact on the temperature field, and the influence of the heat conductivity on temperature field is more obvious than that of specific heat.

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