Thermon gas as the thermal energy carrier in gas and metals  

作　　者：WANG HaiDong GUO ZengYuan 

机构地区：[1]Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Engineering Mechanics Tsinghua Univer-sity, Beijing 100084, China

出　　处：《Chinese Science Bulletin》2010年第29期3350-3355,共6页

摘　　要：The thermon gas may be seen as the main thermal-energy carrier in heat conduction.Consider phonons,which are defined as the energy quanta for quantized lattice vibrationss,and the phonon gas,which consists of a large number of randomly moving phonons.In the same way,a thermon in gas and metal is defined as the equivalent mass of thermal energy of a gas molecule or an electron,respectively,and the thermon gas consists of a large number of randomly moving thermons.Like the phonon and the photon,the rest mass of a thermon is zero.Because the mass of a moving thermon changes continuously,the thermon may be regarded as a nonquantized quasiparticle.Thus,heat flux can be seen as the directional flow of the thermon gas due to a given temperature gradient.The thermon mass is mh=E/c2,where E is the thermal energy and c is the speed of light,and the thermon gas is actually a compressible gas flow with real mass.According to the principle of aerodynamics,the state equations of a thermon gas in either gas or metal are obtained by different statistical functions.Furthermore,Newtonian mechanics may be applied to obtain the momentum-conservation equation of a thermon gas,which is actually the general heat-conduction law,and which reduces to Fourier's law when thermal inertia is negligible.The general heat-conduction law is a damped wave equation that can be used to quantitatively investigate thermal wave phenomena caused by heating of thin metal films by ultrafast laser pulses.The numerical solution of the general heat-conduction law is obtained using a finite-difference method with double precision,and the results show that the thermal wave increases as the spatial inertia of the thermon gas increases.The thermon gas may be seen as the main thermal-energy cartier in heat conduction. Consider phonons, which are defined as the energy quanta for quantized lattice vibrationss, and the phonon gas, which consists of a large number of randomly moving phonons. In the same way, a thermon in gas and metal is defined as the equivalent mass of thermal energy of a gas molecule or an electron, respectively, and the thermon gas consists of a large number of randomly moving thermons. Like the phonon and the photon, the rest mass of a thermon is zero. Because the mass of a moving thermon changes continuously, the thermon may be regarded as a nonquantized quasiparticle. Thus, heat flux can be seen as the directional flow of the thermon gas due to a given temperature gradient. The thermon mass is mh=Elc2, where E is the thermal energy and c is the speed of light, and the thermon gas is actually a compressible gas flow with real mass. According to the principle of aerodynamics, the state equations of a thermon gas in either gas or metal are obtained by different statistical functions. Furthermore, Newtonian mechanics may be applied to obtain the momentum-conservation equation of a thermon gas, which is actually the general heat-conduction law, and which reduces to Fourier＇s law when thermal inertia is negligible. The general heat-conduction law is a damped wave equation that can be used to quantitatively investigate thermal wave phenomena caused by heating of thin metal films by ultrafast laser pulses. The numerical solution of the general heat-conduction law is obtained using a finite-difference method with double precision, and the results show that the thermal wave increases as the spatial inertia of the thermon gas increases.

关 键 词：金属材料 能源载体 天然气 热传导规律 气体分子 空气动力学原理 傅里叶定律 等效质量 

分 类 号：O552.3[理学—热学与物质分子运动论] TG14[理学—物理]