Models of fluidized granular materials: examples of non-equilibrium stationary states
نویسندگان
چکیده
We review some models of granular materials fluidized by means of external forces such as: random homogeneous forcing with viscosity, vibrating plates, flow in an inclined channel and flow in a double well potential. All such systems show the presence of density correlations and non-Gaussian velocity distributions. These models are useful to understand the role of a kinetically defined “temperature” (in this case the so-called granular temperature) in a non-equilibrium stationary state. In the homogeneously randomly driven gas the granular temperature is different from that of the driving bath. Moreover two different granular materials mixed together may stay in a stationary state with different temperatures. At the same time, granular temperature determines (as in equilibrium systems) the escape time from a well in a double well potential. Models of fluidized granular materials 2
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