  We investigate a lattice model representing a granular gas in a thin channel.
We deduce the hydrodynamic description for the model from the microscopic
dynamics in the large system limit, including the lowest finite-size
corrections. The main prediction from hydrodynamics, when finite-size
corrections are neglected, is the existence of a steady "uniform longitudinal
flow" (ULF), with the granular temperature and the velocity gradient both
uniform and directly related. Extensive numerical simulations of the system
show that such a state can be observed in the bulk of a finite-size system by
attaching two thermostats with the same temperature at its boundaries. The
relation between the ULF state and the shocks appearing in the late stage of a
cooling gas of inelastic hard rods is discussed.

Soft Condensed Matter;Statistical Mechanics