Related Experiment Video
Updated: Jul 13, 2026

Thermocapillary Convection Space Experiment on the SJ-10 Recoverable Satellite
Published on: March 11, 2020
Cessations and reversals of the large-scale circulation in turbulent thermal convection
1Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
Abstract:
We present an experimental study of cessations and reversals of the large-scale circulation (LSC) in turbulent thermal convection in a cylindrical cell of aspect ratio (Gamma) 1/2 . It is found that cessations and reversals of the LSC occur in Gamma = 1/2 geometry an order-of-magnitude more frequently than they do in Gamma=1 cells, and that after a cessation the LSC is most likely to restart in the opposite direction, i.e., reversals of the LSC are the most probable cessation events. This contrasts sharply to the finding in Gamma=1 geometry and implies that cessations in the two geometries are governed by different dynamics. It is found that the occurrence of reversals is a Poisson process and that a stronger rebound of the flow strength after a reversal or cessation leads to a longer period of stability of the LSC. Several properties of reversals and cessations in this system are found to be statistically similar to those of geomagnetic reversals. A direct measurement of the velocity field reveals that a cessation corresponds to a momentary decoherence of the LSC.
Related Concept Videos
Reversible and Irreversible Processes
Turbulent Flow
Reynolds Transport Theorem
Control Volume and System Representations
The control volume approach considers a stationary region in space through which fluid flows. This region is bounded by a control surface. For instance, in the case of water flowing...
Laminar and Turbulent Flow
Joule-Thomson Effect
This experiment forces high-pressure gas through a throttle valve or a porous plug to a lower-pressure region. The gas expands as it passes through to...

