ISSN Online: 2377-424X
ISBN Print: 978-1-56700-421-2
International Heat Transfer Conference 15
Experimental and Theoretical Study of Steady Non-Fourier Heat Conduction in Free-Standing Gold Nanofilm
要約
Fourier's law has been found to be violated for heat conduction in low-dimensional materials, but no fully
developed theoretical models have been proposed so far. Recently, a thermomass theory has been developed
by Guo based on Einstein's mass-energy relation. The momentum conservation equation of thermomass is
referred to as the general heat conduction law, which is capable of predicting the non-Fourier phenomena
under the extreme heat conduction conditions quantitatively and reduces to Fourier's law under the normal
heat conduction conditions. The violation of Fourier's law is revealed to be the consequence of nonnegligible
inertia term in the momentum conservation equation of thermomass. In the experiment, a freestanding
gold nanofilm is heated by a large current in the temperature range from 3 K to 60 K, while the
maximum heat flux exceeds 2×1010 W/m2. The measured average temperature of the gold film is remarkably
higher than the prediction of Fourier's law, but agrees well with the prediction of the general heat conduction
law without any adjustable parameters. Hence, the validity of the general heat conduction law has been
proved experimentally. Our results provide strong evidence for the existence of non-Fourier heat conduction
in steady states, and the general heat conduction law shows a great potential in accurate thermal design of
nanoelectric devises with ultra-high heat flux generation.