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arXiv · 1602.00380

Reduction of the effective thermal conductivity by circulation of the quasi-ballistic heat-flux

Ashok T. Ramu·Carl D. Meinhart·John E. Bowers
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Abstract

For a thermal conductivity that is spatially uniform and independent of temperature, Fourier's law of heat transfer predicts a curl-free heat-flux. In the quasi-ballistic phonon transport regime, where the Fourier law breaks down, it has been proven starting from the Boltzmann transport equation that the constitutive relation for the heat-flux contains a solenoidal (circulatory) term with zero divergence and non-zero curl. In this paper we show how to reduce the effective thermal conductivity of a material with dimensions on the same scale as the phonon mean-free path, by exploiting the solenoidal term in the constitutive relation.

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Ashok T. Ramu, Carl D. Meinhart, John E. Bowers. 2016-02-01. Reduction of the effective thermal conductivity by circulation of the quasi-ballistic heat-flux. https://arxiv.org/abs/1602.00380

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