The “adiabatic” piston at equilibrium: Spectral analysis and time-correlation function
Departamento de Física Aplicada, Facultad de Ciencias
Universidad de Salamanca - 37008 Salamanca, Spain
2 EPS de Zamora, Universidad de Salamanca - 49022 Zamora, Spain
Accepted: 31 May 2002
The power spectrum and the time-correlation function of the position of the “adiabatic” piston at equilibrium are investigated. The analysis is made by means of molecular dynamics simulations of two hard-disk gases at equilibrium separated by a movable piston without internal degrees of freedom. For different piston masses we obtain results for some of the main time scales involved in the problem. In particular we obtain an approximate expression for the mass dependence of the piston frequency, its damping constant, and the relaxation time from quasiequilibrium to global equilibrium, in agreement with recent nonequilibrium molecular dynamics simulations of the system.
PACS: 02.50.-r – Probability theory, stochastic processes, and statistics / 64.60.Cn – Order-disorder transformations; statistical mechanics of model systems
© EDP Sciences, 2002