Physics – Fluid Dynamics
Scientific paper
2010-02-15
J. Fluid Mech., Volume 655 (2010) 152-173
Physics
Fluid Dynamics
17 pages, 11 Postscript figures (in parts downscaled), accepted for J. Fluid Mech
Scientific paper
10.1017/S0022112010000820
The heat transport and corresponding changes in the large-scale circulation (LSC) in turbulent Rayleigh-B\'{e}nard convection are studied by means of three-dimensional direct numerical simulations as a function of the aspect ratio $\Gamma$ of a closed cylindrical cell and the Rayleigh number $Ra$. For small and moderate aspect ratios, the global heat transfer law $Nu=A\times Ra^{\beta}$ shows a power law dependence of both fit coefficients $A$ and $\beta$ on the aspect ratio. A minimum Nusselt number coincides with the point where the LSC undergoes a transition from a single-roll to a double-roll pattern. With increasing aspect ratio, we detect complex multi-roll LSC configurations. The aspect ratio dependence of the turbulent heat transfer for small and moderate $\Gamma$ is in line with a varying amount of energy contained in the LSC, as quantified by the Proper Orthogonal Decomposition analysis. For $\Gamma\gtrsim 8$ the heat transfer becomes independent of the aspect ratio.
Bailon-Cuba Jorge
Emran Mohammad S.
Schumacher Joerg
No associations
LandOfFree
Aspect ratio dependence of heat transfer and large-scale flow in turbulent convection does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Aspect ratio dependence of heat transfer and large-scale flow in turbulent convection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aspect ratio dependence of heat transfer and large-scale flow in turbulent convection will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-146302