A Poiseuille Viscometer for Lattice Gas Automata

A b stra ct . Lattice gas automata have been recently proposed as a new technique for the numerical integration of the two-dimensional Nav ier-Stokes equation. We have accurately tes ted a stra ightforward var iant of the original model, due to Fr isch, Hasslacher, and Pomeau, in a simp le geometry equivalent to two-dimensional Poiseuille (Cha nnel) flow dr iven by a uniform body force. The momentum density profile produced by this simulation agrees well with the pa rabolic pro file predicted by the macroscopic descript ion of the gas given by Frisch et al. We have used the simulated flow to com pute t he shea r viscosity of the lat tice gas and have found ag reement with the results obtained by d 'Humieres et al. 110] using shear wave re laxation measurements , and, in t he low density limit , with theoretica l predictions obtained from the Boltzmann description of the gas [171 .