Figure 1

Cartoon illustrates the experimental configuration of the current study. The Rayleigh-Bénard system at steady-state is set up by heating a thin film of viscous liquid from the bottom (\(\dot{Q}\)). The temperature difference between T_bottom and T_top gives rise to convection rolls. While at steady-state, T_bottom is constant, real-time thermal imaging of the top layer is performed to extract the spatial and temporal distribution of T_top. The line cut of the thermal profile \({T}_{top}({\bf{r}},t)\) is also shown. As the goal was to have convection cells over as wide as an area possible for the thermal imaging to yield significant temperature statistics, a large diameter to thickness ratio of the apparatus (\(2R/{l}_{z}\simeq 225\,mm\)/\(5\,mm\sim 45\)) yielded a stable convection cell pattern \(\gtrsim \,150\,mm\) in diameter and stable for as long as the power was applied.