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arXiv · 1505.02465

On the solenoidal heat-flux in quasi-ballistic thermal conduction

Ashok T. Ramu·John E. Bowers
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Abstract

The Boltzmann transport equation for phonons is recast directly in terms of the heat-flux by means of iteration followed by truncation at the second order in the spherical harmonic expansion of the distribution function. This procedure displays the heat-flux in an explicitly coordinate-invariant form, and leads to a natural decomposition into two components, namely the solenoidal component in addition to the usual irrotational component. The solenoidal heat-flux is explicitly shown to arise by applying the heat-flux equation to a right-circular cylinder. These findings are important in the context of phonon resonators that utilize the strong quasi-ballistic thermal transport reported recently in silicon membranes at room temperature.

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Ashok T. Ramu, John E. Bowers. 2015-05-11. On the solenoidal heat-flux in quasi-ballistic thermal conduction. https://doi.org/10.1063/1.4931610

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