Title: Nonequilibrium phase transition in a 2D isobaric granular fluid

Author (Talk): Rohit Ingale, Pall Life Sciences

Abstract:

We present experimental evidence for a first-order freezing/melting phase transition in a nonequilibrium system ---an oscillated two-dimensional isobaric granular fluid. The steady-state transition occurs between a gas and a crystal and is characterized by a discontinuous change in both density and temperature. The phase transition shows rate-dependent hysteresis and free energy/entropiclike features analogous to those developed for equilibrium phase transition studies. We thus propose a phenomenological model analogous to Ginzburg-Landau free energy functional to explain the observed behavior of the system in the vicinity of the phase transition. In addition, we measure the equation of state both above and below the phase transition which compares well with theory.