Determination of thermal conductivity and diffusivity by transient heating of a thin slab

Abstract

Transient heat conduction through a thin slab which is initially at a constant temperature, and subsequently heated by free convection in a thermal bath, is a well established theory. From the theory, it is deduced that a thickness to length ratio of 0.2 is adequate to achieve one-dimentional heat flow in the middle of a square slab. Using the theory, the non-dimensional temperature-time history for the midpoint of the slab is obtained. From these non-dimensional plots, a statistical scheme of finding the best fit between experimental data and the theory is described. By obtaining the best fit, the most probable values of the thermal conductivity and diffusivity are obtained directly. © 1992.