This example is a classic one-dimensional transient heat diffusion problem where a solid rod of unit length is kept at fixed temperature at the right end, T = 25, and losing heat from a constant outward heat flux qn = 1 at the other end. After the simulation the computed results can be compared with the analytic reference solution
$$ T_{ref} = (24+x) + \sum_{n=1}^\infty 8/(1-2n)^2/\pi^2cos((n-1/2)\pi x)e^{-((n-1/2)^2\pi^2)t}$$
This model is available as an automated tutorial by selecting Model Examples and Tutorials… > Heat Transfer > Transient Heat Diffusion in a Rod from the File menu, and also as the MATLAB simulation m-script example ex_heattransfer1. Step-by-step tutorial instructions to set up and run this model are linked below.