Heat conductivity by a shared piston

Abstract

We study the heat transfer between two reservoirs, filled with hard disks (mass m) at different temperature, resulting from the collisions with a common piston (mass M). The predictions of a linear Langevin equation are found to be in very good agreement with molecular-dynamics simulations for both a dense Enskog and a dilute Boltzmann gas for a mass ratio M/m as low as 10. Results based on the Boltzmann equation and on an exactly solvable one-dimensional model describe well the case M = m of equal masses.