Origin of the Temperature Oscillation in Turbulent Thermal Convection

Abstract

We report an experimental study of the three-dimensional spatial structure of the low frequency temperature oscillations in a cylindrical Rayleigh-Bénard convection cell. It is found that thermal plumes are not emitted periodically, but randomly and continuously, from the top and bottom plates. We further found that the oscillation of the temperature field does not originate from the boundary layers, but rather is a result of the horizontal motion of the hot ascending and cold descending fluids being modulated by the twisting and sloshing motion of the bulk flow field.

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References in corpus (3)

• Rotations and cessations of the large-scale circulation in turbulent Rayleigh-Benard convection
• A model of diffusion in a potential well for the dynamics of the large-scale circulation in turbulent Rayleigh-Benard convection
• Measured oscillations of the velocity and temperature fields in turbulent Rayleigh-Bénard convection in a rectangular cell