Author(s)

N. Simões, I. Simões, A. Tadeu, C. Vasconcellos & W. Mansur

Abstract

This paper analyses heat transfer across multilayer systems when boundary conditions are unsteady. The results of analytical simulations and experimental tests were compared in order to validate the analytical formulation. The formulation that is proposed to solve this problem uses Green’s functions to handle the conduction phenomena. The Green’s functions are established by imposing the continuity of temperatures and heat fluxes at the interfaces of the various layers. The technique used to deal with the unsteady state conditions consists of first computing the solution in the frequency domain (after the application of time and spatial Fourier transforms along the two horizontal directions), and then applying (fast) inverse Fourier transforms into space-time. The thermal properties of the multilayer system materials have been previously defined experimentally. For the experimental measurements the multilayer system was mounted on a guarded hotplate capable of imposing a controlled heat variation at the top and bottom boundaries of the system. Temperatures were recorded using a thermocouple set connected to a data logger system. Comparison of the results showed that the analytical solutions agree with the experimental ones. Keywords: experimental validation, transient heat conduction, Green’s functions formulation, frequency domain.

Keywords

experimental validation, transient heat conduction, Green’s functions formulation, frequency domain