• CN: 11-2187/TH
  • ISSN: 0577-6686

›› 2009, Vol. 45 ›› Issue (3): 10-13.

• Article • Previous Articles     Next Articles

Thermal Mass

GUO Zengyuan;WU Jing;CAO Bingyang   

  1. Department of Engineering Mechanics, Tsinghua University
  • Published:2009-03-15

Abstract: Heat is the energy of molecules moving randomly. Based on the mass-energy relation in Einstein’s relativity theory, thermal energy has equivalent mass, which is referred to as thermal mass. The velocity of the motion of thermal mass can be extracted from the quantity of heat flux. The driving force of thermal mass motion is obtained by establishing the equation of state of a phonon gas (thermal mass gas). Since the heat conduction is just the motion of the thermal mass in a medium, the momentum conservation equation for thermal mass is a general heat conduction law which can unify the description of heat conductions under various conditions. When the heat flux is not very high, the general heat conduction law will reduce to Fourier’s law. When the heat flux is so high that the spatial inertial force cannot be ignored, the general law will reduce to CV (Cattaneo-Vernotte) model. The general heat conduction law will reduce to a steady state heat conduction law with a spatial inertial force item when the heat flux in a steady state heat conduction is extremely high, which indicates that non-Fourier phenomenon may take place even in steady state cases.

Key words: General law, Non-Fourier heat conduction, Thermal mass

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