Particle simulation of three-dimensional convection patterns in a Rayleigh-Bénard system

Abstract

The transition of convection patterns in the three-dimensional Rayleigh-B{acute e}nard system is simulated using the direct simulation Monte Carlo method. The simulation region is a rectangular box with an aspect ratio of 8:8:1, and the number of simulation particles is 2.048{times}10{sup 7}. A hexagonal flow pattern is observed in the convection state with the Rayleigh number slightly higher than the critical value. It is found that the hexagonal flow pattern evolves into a roll pattern with an increase in the Rayleigh number. A hysteresis is seen in the transition between the hexagonal and roll patterns. {copyright} {ital 1997} {ital The American Physical Society}