A comparison of turbulent thermal convection between conditions of constant temperature and constant heat flux
نویسندگان
چکیده
We numerically investigate turbulent thermal convection driven by a horizontal surface of constant heat flux and compare the results with those of constant temperature. Below Ra≈ 10, where Ra is the Rayleigh number, when the flow is smooth and regular, the heat transport in the two cases is essentially the same. For Ra> 10 the heat transport for imposed heat flux is smaller than that for constant temperature, and is close to experimental data. We provide a simple dimensional argument to indicate that the unsteady emission of thermal plumes renders typical experimental conditions closer to the constant heat flux case.
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Comparison of turbulent thermal convection between conditions of constant temperature and constant flux.
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