A rational criterion for accuracy of modelling of periodic heat conduction in plane slabs

Abstract The temperature response of a slab wall to a sinusoidal heat flux input wave is expressed in dimensionless from and its behavior examined for two simple boundary conditions over a range of frequencies. A dimensionless parameter, w L2/K, is introduced and it is shown that its value governs the responses. A comparison is made between the response of the distributed case and that of a number of lumped equivalent models. The errors involved in using the lumped models are shown. Examples are given of applications of the results.