Largescale flow generation in turbulent convection
Abstract
In a horizontal layer of fluid heated from below and cooled from above, cellular convection with horizontal length scale comparable to the layer depth occurs for small enough values of the Rayleigh number. As the Rayleigh number is increased, cellular flow disappears and is replaced by a random array of transient plumes. Upon further increase, these plumes drift in one direction near the bottom and in the opposite direction near the top of the layer with the axes of plumes tilted in such a way that horizontal momentum is transported upward via the Reynolds stress. With the onset of this largescale flow, the largest scale of motion has increased from that comparable to the layer depth to a scale comparable to the layer width. The condiditions for occurence and determination of the direction of this largescale circulation are described.
 Publication:

National Academy of Sciences
 Pub Date:
 April 1981
 Bibcode:
 1981nas....78.1981K
 Keywords:

 Convective Flow;
 Flow Stability;
 Heat Flux;
 Rayleigh Number;
 Transition Flow;
 Turbulent Flow;
 Flow Distribution;
 Flow Geometry;
 Free Convection;
 Plumes;
 Thermal Conductivity;
 Fluid Mechanics and Heat Transfer