Spontaneous and stochastic reversal of large scale flow structure is an intriguing and crucial phenomenon in turbulent Rayleigh-Bénard type natural convection. This paper proposes a new control approach to eliminate the reversals through stabilising the corner flows using two small sidewall controllers. Based on a series of direct numerical simulations, it is shown that the control can successfully stop the growth of corner vortices and suppress the reversal of large-scale circulation, if the width of sidewall controllers installed within or near the top of corner vortices is large enough. When the controllers are located around the centre, they can easily break up the large-scale structures or even divide the single roll mode into a double-roll mode for very large widths. Moreover, the influence of sidewall controllers on the heat transport is studied. It is shown that the heat transport efficiency can be slightly enhanced or suppressed when the proper location and width are chosen. The present findings provide a new idea to control the large-scale flow structure and reversals in thermally driven convection through sidewall controlling.

大规模流动结构的自发和随机逆转是湍流 Rayleigh-Bénard 型自然对流中一个有趣且关键的现象。本文提出了一种新的控制方法，通过使用两个小侧壁控制器稳定角流来消除逆转。一系列直接数值模拟表明，如果安装在角涡顶部内或附近的侧壁控制器的宽度较大，该控制可以成功地阻止角涡的增长并抑制大规模环流的逆转。足够的。当控制器位于中心附近时，它们可以很容易地分解大型结构，甚至可以将单辊模式划分为非常大宽度的双辊模式。而且，研究了侧壁控制器对传热的影响。It is shown that the heat transport efficiency can be slightly enhanced or suppressed when the proper location and width are chosen. 目前的发现为通过侧壁控制来控制热驱动对流中的大规模流动结构和逆转提供了一种新思路。