Solid-like heat transfer in confined liquids

Michael Frank, Dimitris Drikakis

Research output: Contribution to journalArticle

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Abstract

The aim of this research is to identify possible mechanisms that govern heat transport at a solid-liquid interface using molecular dynamics. The study reveals that, unlike its bulk analogue, a liquid in a nanochannel sustains long-lived collective vibrations, phonons, which propagate over longer timescales and distances. The larger phonon mean free path in nanochannels is attributed to the greater structural order of the liquid atoms and to the larger liquid relaxation time–the time in which the liquid structure remains unchanged and solid-like. For channels of height less than 10σ, long-range phonons are the dominant means of heat transfer in the directions parallel to the channel walls. The present findings are in agreement with experiments, which have observed significantly increased liquid relaxation times for the same range of channel heights. Finally, it is argued that confinement introduces additional transverse modes of vibration that also contribute to the thermal conductivity enhancement.
Original languageEnglish
Article number148
Number of pages6
JournalMicrofluidics and Nanofluidics
Volume21
Issue number9
Early online date24 Aug 2017
DOIs
Publication statusPublished - 30 Sep 2017

Fingerprint

heat transfer
Heat transfer
Liquids
liquids
Phonons
phonons
Relaxation time
relaxation time
liquid-solid interfaces
mean free path
vibration mode
thermal conductivity
Molecular dynamics
Thermal conductivity
analogs
molecular dynamics
heat
vibration
augmentation
Atoms

Keywords

  • heat transfer
  • thermal conductivity
  • confined liquid
  • phonons
  • density of states
  • relaxation time

Cite this

Frank, Michael ; Drikakis, Dimitris. / Solid-like heat transfer in confined liquids. In: Microfluidics and Nanofluidics. 2017 ; Vol. 21, No. 9.
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Solid-like heat transfer in confined liquids. / Frank, Michael; Drikakis, Dimitris.

In: Microfluidics and Nanofluidics, Vol. 21, No. 9, 148, 30.09.2017.

Research output: Contribution to journalArticle

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