Diffusion

Abstract

A common example of diffusion is given by the heat conduction in a solid body. Conduction comes from molecular collision, transferring heat by kinetic energy, without macroscopic material movement. If the medium is homogeneous and isotropic with respect to the heat propagation, the evolution of the temperature is described by equation (2.1); f represents the intensity of an external distributed source. For this reason eq. (2.1) is also known as the heat equation.