Single sidewall cooling modulation on Rayleigh–Bénard convection

We experimentally explored the effect of single-sidewall cooling on Rayleigh–Bénard (RB) convection. Canonical RB was also studied to aid insight. The scenarios shared tank dimensions and bottom top wall temperatures; single sidewall had temperature. Turbulence at two canonical Rayleigh numbers, $Ra=1.6\times 10^{10}$ $Ra=2\times 10^9$ under Prandtl number $Pr=5.4$ . Particle image velocimetry described vertical planes parallel perpendicular cooling. $Ra$ reveal pronounced changes in flow structure large-scale circulation (LSC) due density gradient induced by led asymmetric descending ascending flows irregular LSC. Flow statistics departed from case, exhibiting lower buoyancy effects, represented an effective with height dependent distance lateral Velocity spectra show scalings, $\varPhi \propto f^{-5/3}$ Kolmogorov (KO41) f^{-11/5}$ Bolgiano (BO59) larger ; latter not present smaller set-up. BO59 scaling appears higher frequencies than its counterpart, suggesting weaker effects. LSC core motions allowed us identify a characteristic time scale order vortex turnover associated distinct modes. velocity oscillation along principal axis showed _c for cooling, which dominant closer there. It did occur evidencing modulation flow.