Turbulent convection with time-dependent forcing
نویسندگان
چکیده
A new technique is used to explore the structure of turbulent convecting flows. A sinusoidal temperature perturbation is superimposed on the bottom plate of a cylindrical convection cell filled with cryogenic helium gas and its decay is measured at the cell mid-height. The measurements allow the first dynamic estimate of the core part of the flow which conducts fluid effectively without any thermal resistance. The estimate is quantitatively consistent with recent numerical simulations.
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