Energies (Nov 2021)

Bragg Mirrors for Thermal Waves

  • Angela Camacho de la Rosa,
  • David Becerril,
  • María Guadalupe Gómez-Farfán,
  • Raúl Esquivel-Sirvent

DOI
https://doi.org/10.3390/en14227452
Journal volume & issue
Vol. 14, no. 22
p. 7452

Abstract

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We present a numerical calculation of the heat transport in a Bragg mirror configuration made of materials that do not obey Fourier’s law of heat conduction. The Bragg mirror is made of materials that are described by the Cattaneo-Vernotte equation. By analyzing the Cattaneo-Vernotte equation’s solutions, we define the thermal wave surface impedance to design highly reflective thermal Bragg mirrors. Even for mirrors with a few layers, very high reflectance is achieved (>90%). The Bragg mirror configuration is also a system that makes evident the wave-like nature of the solution of the Cattaneo-Vernotte equation by showing frequency pass-bands that are absent if the materials obey the usual Fourier’s law.

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