English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Previous studies have predicted the failure of Fourier's law of thermalconduction due to the existence of wave like propagation of heat with finitepropagation speed. This non-Fourier thermal transport phenomenon can appear inboth the hydrodynamic and (quasi) ballistic regimes. Hence, it is not easy toclearly distinguish these two non-Fourier regimes only by this phenomenon. Inthis work, the transient heat propagation in homogeneous thermal system isstudied based on the phonon Boltzmann transport equation (BTE) under theCallaway model. Given a quasi-one or quasi-two (three) dimensional simulationwith homogeneous environment temperature, at initial moment, a heat source isadded suddenly at the center with high temperature, then the heat propagatesfrom the center to the outer. Numerical results show that in quasi-two (three)dimensional simulations, the transient temperature will be lower than thelowest value of initial temperature in the hydrodynamic regime within a certainrange of time and space. This phenomenon appears only when the normalscattering dominates heat conduction. Besides, it disappears in quasi-onedimensional simulations. Similar phenomenon is also observed in thermal systemswith time varying heat source. This novel transient heat propagation phenomenonof hydrodynamic phonon transport distinguishes it well from (quasi) ballisticphonon transport.

A novel transient heat conduction phenomenon to distinguish the hydrodynamic and (quasi) ballistic phonon transport