This article studied the potential thermal conductivity deviation of anisotropic materials using a numerical simulation. Anisotropic thermal conductivity may experience deviation due to its noncompliance of the theoretical assumption of the transient plane source (TPS) method. The TPS method was used to measure the in-plane and through-plane thermal conductivities of anisotropic materials where the volumetric heat capacity was known. It was found that the TPS method could be used to ...
The authors present a multiple-relaxation-time lattice Boltzmann model with an off-diagonal collision matrix for use in predicting the thermal conductivity of anisotropic heterogeneous materials with anisotropic components. Model accuracy was first confirmed through comparison with previous simulation results. In this paper the model was applied to measure the tranverse and longitudinal thermal conductivities of 3D4D braided composites. The TPS method was used to measure the conductivities experimentally for comparison ...
Currently, there is no research into the accuracy of the transient plane source (TPS) method for measuring the thermal conductivity of thin films. The purpose of this study is to use numerical simulation to determine the accuracy of thermal conductivity measurements of thin films, with the TPS method. The values produced from the TPS method closely resembled those of the numerical simulation. The deviations from the numerical model were caused ...
Proton exchange membranes (PEM) are important components of proton exchange membrane fuel cells (PEMFC) which could potentially substitute fossil energy. The purpose of this study was to theoretically and experimentally study how the thermal conductivity of the PEM, Nafion 117, is related to water content and temperature. A thermal analyzer measured the thermal conductivity of dry Nafion 117 using the transient plane source (TPS) method. Results showed that, as predicted, the thermal ...
Aerogels are nano-porous materials with impressive thermal insulation properties. This study uses a new theoretical model to predict the effective thermal conductivity of aerogels based on gas and solid conduction, as well as thermal radiation. A thermal constant analyzer measured the influence of gas pressure, atmosphere, and temperature on the thermal conductivity of nano-porous materials using the transient plane source (TPS) method. Results showed that the experimental thermal conductivity values ...
