Fluid dynamic limit for a modified Broadwell system

This report discusses a new approach to the resolution of the fluid dynamic limit for the Broadwell system modeling gas dynamics. The main idea is to replace the Knudsen number ε in the Broadwell model by εt , t the time variable to obtain self similar solutions in ξ=x/ t and then let ε → 0+. The limit thus obtained is a solution of the Riemann problem for the fluid dynamic limit equations.