2006/12/13 by Eric Brown, Guenter Ahlers, Brown, Eric +1
Engineering · Physics and Astronomy · #Fluid Dynamics and Turbulent Flows #physics.flu-dyn
paper · pdf · doi:10.48550/arxiv.physics/0612120
Submitted to Physical Review Letters. 4 pages, 3 figures
arxiv created 2006/12/13 · arxiv updated 2009/12/01
A model for the large-scale circulation (LSC) dynamics of turbulent Rayleigh-Benard convection is presented. It consists of two stochastic ordinary differential equations motivated by the Navier-Stokes equation, one each for the strength and the azimuthal orientation of the LSC. Stochastic forces represent phenomenologically the action of the turbulent fluctuations on the LSC. Without adjustable parameters, the model yields a meandering LSC with occasional rotations, and with more rare cessations that occur a few times per day -- differing only by about a factor of two from experiment. Also as in experiments, the distribution of LSC orientation-change is uniform for cessations and a power law for rotations.