ISSN Online: 2377-424X
ISBN Print: 1-56032-797-9
International Heat Transfer Conference 11
THERMAL WAVE CHARACTERISTICS IN A FINITE MEDIUM
Resumo
Fourier's law of heat conduction has been applied in
solving conduction problems encountered in practice.
This law predicts instantaneous heat diffusion with
infinite propagation speed. Some recent experiments
show the reflections of thermal waves at the interface of
dissimilar materials at cryogenic temperature. In
situations involving transient heat flow in very short time
or at cryogenic temperature, the effects of finite speed of
heat propagation become important. The thermal wave
characteristics of damping and resonance are derived
from the thermal wave 'equation through both modified
heat flux equation and energy conservation law. The
thermal resonance and phase lags of heat flux in a finite
medium with thermal relaxation time are studied in this
work by Finite Fourier transform with respect to space.
As the result of the transformation with respect to space,
the resonance and phase lags on underdamped condition
are found when the modal frequencies in the medium
exceed a critical value. The relationship between the
modal frequencies to occur a resonance and the resonance
frequencies is obtained.