O. Benois, R. Esposito, R. Marra Navier-Stokes limit for a thermal stochastic lattice gas (479K, Postscript) ABSTRACT. We study a stochastic particle system on the lattice whose particles move freely according to simple exclusion process and change velocities during collisions preserving energy and momentum. In the hydrodynamic limit, under diffusive space-time scaling, the local velocity field $u$ satisfies the incompressible Navier-Stokes equation, while the temperature field $\t$ solves the heat equation with drift $u$. The results are also extended to include a suitably rescaled external force.