Richard J.A.M. Stevens

Physics of Fluids · University of Twente

Publication 9 · Thermal convection

Flow reversals in thermally driven turbulence

K. Sugiyama, R. Ni, R.J.A.M. Stevens, T.S. Chan, S.-Q. Zhou, H.-D Xi, C. Sun, S. Grossmann, K.-Q. Xia, D. Lohse, Phys. Rev. Lett. 105, 034503 (2010).

Main finding

A diagonal main roll coexists with two counter-rotating corner rolls. Plume-fed corner rolls grow to a linear extent of about H/2, destroy the main roll, and establish the opposite circulation; some growth episodes instead decay without reversal. Mean reversal intervals rise rapidly above roughly Ra=2×10^8.

Temperature and velocity fields through a convection flow reversal, with the angular momentum trace
How to read the figure. (a-c, e-g) Temperature in colour with velocity vectors at successive instants spanning a reversal, showing a diagonal main roll flanked by two counter-rotating corner rolls. (d, h) Angular momentum over time with those instants marked: the corner rolls grow until the main roll is displaced and the circulation reverses. Open the full-resolution figure. Figure 1. K. Sugiyama et al. (2010). No separate licence is stated here; consult the original publication and credited source before reuse.

Why this matters

A diagonal main roll coexists with two counter-rotating corner rolls. Plume-fed corner rolls grow to a linear extent of about H/2, destroy the main roll, and establish the opposite circulation; some growth episodes instead decay without reversal.

Research context

The corner-roll takeover sequence is directly supported in the sampled rectangular cells and two-dimensional simulation. It does not establish the same mechanism for reversals in three-dimensional cylindrical convection.

Read the article View in the complete publication list Related thermal convection research