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Power-Law Behavior of Power Spectra in Low Prandtl Number Rayleigh-Benard Convection

M. R. Paul·M. C. Cross·P. F. Fischer·H. S. Greenside
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Abstract

The origin of the power-law decay measured in the power spectra of low Prandtl number Rayleigh-Benard convection near the onset of chaos is addressed using long time numerical simulations of the three-dimensional Boussinesq equations in cylindrical domains. The power-law is found to arise from quasi-discontinuous changes in the slope of the time series of the heat transport associated with the nucleation of dislocation pairs and roll pinch-off events. For larger frequencies, the power spectra decay exponentially as expected for time continuous deterministic dynamics.

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M. R. Paul, M. C. Cross, P. F. Fischer, H. S. Greenside. 2001-05-02. Power-Law Behavior of Power Spectra in Low Prandtl Number Rayleigh-Benard Convection. https://doi.org/10.1103/physrevlett.87.154501

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