  We study some statistical properties for the behavior of the average squared
velocity -- hence the temperature -- for an ensemble of classical particles
moving in a billiard whose boundary is time dependent. We assume the collisions
of the particles with the boundary of the billiard are inelastic leading the
average squared velocity to reach a steady state dynamics for large enough
time. The description of the stationary state is made by using two different
approaches: (i) heat transfer motivated by the Fourier law and, (ii) billiard
dynamics using either numerical simulations and theoretical description.
