Heat conduction - Sinusoidal thermal modulation through the heterogeneous cover of an infinite wall

The author considers the case of a heterogeneous wall consisting of a succession of finite walls except the final downstream wall, which is of infinite thickness, and analyzes with the aid of sinusoidal S functions the effects of a thermal modulation applied continuously at the upstream surface. This corresponds to the case of a homogeneous ground with composite cover exposed to the diurnal or annual temperature variation. The 'backwards computation' technique is set forth for calculating flux density and temperature components.