Determining the effective thermal conductivity of a quasi-two-dimensional nonhomogeneous structure

1992 ◽  
Vol 61 (6) ◽  
pp. 2421-2425
Author(s):  
V. A. Chugunov ◽  
O. V. Yartsev
Keyword(s):  
Thermal Conductivity ◽  
Effective Thermal Conductivity ◽  
Two Dimensional ◽  
Nonhomogeneous Structure

Experimental and Numerical Research on Effective Thermal Conductivity of Granular Porous Media

2011 ◽  
Vol 320 ◽  
pp. 353-358
Author(s):  
Yu Feng Shi ◽  
Wen Ce Sun ◽  
Li Hua Shi ◽  
Jing Cui
Keyword(s):  
Thermal Conductivity ◽  
Porous Media ◽  
Effective Thermal Conductivity ◽  
Experimental System ◽  
Two Dimensional ◽  
Infinite Body ◽  
Fractal Method ◽  
Granular Porous Media ◽  
Unsteady Heat Conduction ◽  
Numerical Research

Effective thermal conductivity of granular porous media is investigated by experimental and numerical methods. Using the unsteady heat conduction formula of semi-infinite body, effective thermal conductivity is obtained by measuring temperature field of the experimental system. In this experiment, solid particle is pebble and pore fluid is water or brine with salinity of 20.2%. Granular porous media is not applicable for fractal method, therefore based on structural character of granular porous media; two-dimensional cylinder model is used to calculate effective thermal conductivity of granular porous media in this paper. The simulation results correspond well with the experimental results. This proves that calculating effective thermal conductivity of granular porous media by using this two-dimensional model is accurate. This model could be extrapolated to unsaturated porous media. Research shows that effective thermal conductivity increases logarithmically with the increasing of saturation.

scholarly journals Calculations of the Effective Thermal Conductivity in a Model of Syntactic Metallic Hollow Sphere Structures Using a Lattice Monte Carlo Method

2008 ◽  
Vol 273-276 ◽  
pp. 216-221 ◽  
Author(s):  
Thomas Fiedler ◽  
Andreas Öchsner ◽  
Irina V. Belova ◽  
Graeme E. Murch
Keyword(s):  
Thermal Conductivity ◽  
Monte Carlo ◽  
Monte Carlo Method ◽  
Effective Thermal Conductivity ◽  
Hollow Sphere ◽  
Cutting Planes ◽  
Two Dimensional ◽  
Adhesively Bonded ◽  
Lattice Monte Carlo ◽  
The Matrix

In this paper, a Lattice Monte Carlo method is used to determine the effective thermal conductivity in two dimensional models of adhesively bonded metallic hollow sphere structures (MHSS). In contrast to earlier approaches, more realistic distributions of spheres without the simplification of cubic symmetric arrangements are considered in this study. For the Monte Carlo analyses, two-dimensional periodic lattices representing different cutting planes through MHSS are generated. Therefore, an algorithm is used which sequentially fills the lattice by adding cut spherical shells and inclusions in the matrix. Another focus of this work is the analysis of the influence of different geometric circle distributions on the effective thermal conductivity. The findings of the random arrangements are also compared to a regular primitive cubic arrangement and with a Maxwell-type approach.

Effective Thermal Conductivity of Ordered Mesoporous Carbon CMK-3

2013 ◽  
Author(s):  
Daili Feng ◽  
Yanhui Feng ◽  
Xinxin Zhang ◽  
Ge Wang
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Effective Thermal Conductivity ◽  
Mesoporous Carbon ◽  
Two Dimensional ◽  
Hexagonal Array ◽  
Coupled Heat Transfer ◽  
Ordered Mesoporous ◽  
Carbon Rods ◽  
Conductivity Models

CMK-3 is a typical of carbon rods which are arranged in relatively regular two-dimensional hexagonal array. In our study, the effective thermal conductivity of CMK-3 composite is investigated. For the thermal conductivity of carbon rods, the equilibrium molecular dynamics (EMD) is performed with Tersoff potential. The influences of porosity and temperature are also considered. For the thermal conductivity of air confined in mesoporous can be estimated by the frequently used Kaganer model. Then, the effective thermal conductivity models developed for coupled heat transfer of air and solid are obtained by the unit cell method. ETCs along the X and Y directions are extremely poor, due to the overwhelming effect of air thermal resistance. However, in the Z direction, the ETC improves almost linearly as the porosity decreases, and the value is much higher than those of X and Y directions. This study is in attempts to explore the possibility of CMK-3 being a proper substrate for thermal usage.

Two-dimensional lattice Boltzmann modeling for effective thermal conductivity in carbon black filled composites

2017 ◽  
Vol 52 (15) ◽  
pp. 2047-2053 ◽  
Author(s):  
Yong-Jun Kim ◽  
Yu-Fei Tan ◽  
Sok Kim
Keyword(s):  
Experimental Data ◽  
Thermal Conductivity ◽  
Carbon Black ◽  
Effective Thermal Conductivity ◽  
Lattice Boltzmann ◽  
Volume Fraction ◽  
Effective Properties ◽  
Lattice Boltzmann Model ◽  
Two Dimensional ◽  
Boltzmann Model

Polymer composites filled with thermally conductive particles are widely used in thermo-electronic industry, and the prediction of effective properties is still important for design and use of composites. Thus, we propose a lattice Boltzmann model to predict the effective thermal conductivity of composites filled with carbon black. First, a method for reconstructing numerical material having filler distribution characteristic similar to that of actual material is introduced, and the process for obtaining the phase function and the volume fraction of grain filler is described. The energy transport governing equation is then solved through the two-dimensional discrete structure by using a lattice Boltzmann model. The effective thermal conductivity of two-phase composite is expressed by the conductivity of each phase and the temperature distribution in discrete rectangle. The resultant prediction is compared with theoretical and experimental data and indicates good agreement with experimental data.

In-Plane Effective Thermal Conductivity of Symmetric, Diamond-Weave Screen Laminates

2004 ◽  
Vol 127 (3) ◽  
pp. 353-356 ◽  
Author(s):  
Jun Xu ◽  
Richard A. Wirtz
Keyword(s):  
Thermal Conductivity ◽  
Specific Surface ◽  
Effective Thermal Conductivity ◽  
Surface Area ◽  
Specific Surface Area ◽  
Laboratory Experiments ◽  
Two Dimensional ◽  
Algebraic Models ◽  
Metal Fractions

Algebraic models of porosity, specific surface area, and in-plane effective thermal conductivity for stacked, two-dimensional symmetric diamond-weave screen laminations are developed and benchmarked with laboratory experiments. Diamond-weave laminations are found to have greater metal fractions and specific surface area than equivalent orthogonal-weaves. With the weave angle smaller than 90°, the structure also has a much higher effective thermal conductivity.

Sign in / Sign up

Export Citation Format

Share Document