Manipulating Heat Flow through 3 Dimensional Nanoscale Phononic Crystal Structure

Abstract

In this project, we have studied, through computer simulation, how the three dimensional (3D) phononic crystal structures can confine phonon and thus reduce thermal conductivity significantly leading to an enhancement of efficiency of energy conversion in thermoelectric applications. In particular, we have studied a nanoscale 3D Si phononic crystal (PnC) with spherical pores, which can reduce thermal conductivity of bulk Si by a factor up to 10,000 times at room temperature. The phonon participation ratio spectra demonstrate that more phonons are localized as the porosity increases. The thermal conductivity is found insensitive to the temperature changes from room temperature to 1,100K. The effect of period length and mass ratio on thermal conductivity is also studied.

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Document Details

Document Type
Technical Report
Publication Date
Jun 02, 2014
Accession Number
ADA602272

Entities

People

  • Baowen Li

Organizations

  • National University of Singapore

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Abstracts
  • Climate Change
  • Computer Simulations
  • Conductivity
  • Crystal Structure
  • Crystals
  • Department Of Defense
  • Energy Conversion
  • Heat Transmission
  • Information Operations
  • Simulations
  • Singapore
  • Thermal Conductivity
  • Three Dimensional

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Nanocomposite Materials Science
  • Thermal Physics or Thermal Science.