Periodic compression of an adiabatic gas: Intermittency enhanced Fermi   acceleration
  A gas of noninteracting particles diffuses in a lattice of pulsating scatterers. In the finite horizon case with bounded distance between collisions and strongly chaotic dynamics, the velocity growth (Fermi acceleration) is well described by a master equation, leading to an asymptotic universal non-Maxwellian velocity distribution scaling as v ~ t. The infinite horizon case has intermittent dynamics which enhances the acceleration, leading to v ~ t ln t and a non-universal distribution. 
Carl P. Dettmann and Edson D. Leonel
nlin.CD math-ph math.MP