COUPLED MAP LATTICE MODEL FOR CONVECTION

A coupled map lattice model for convection is proposed, which consists of Eulerian and Lagrangian procedures. Simulations of the model repro duce wide-ranged phenomena in Benard convection experiments: For a sma ll aspect ratio, formation of convective rolls, their oscillation, and many routes to chaos are found, with the increase of Rayleigh number. For a large aspect ratio, spatiotemporal intermittency is observed. F or a high Rayleigh number, transition from soft to hard turbulence is confirmed, as is characterized by the temperature distribution change from Gaussian to exponential. The roll formation in a three-dimensiona l convection is also simulated, which reproduces experiments well.