Wave concepts in the theory of heat
Wave concepts in the theory of heat
复制标题
热理论中的波概念
DOI:
10.1016/0017-9310(76)90110-1
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发表时间:
1976
影响因子:
5.2
通讯作者:
V. Bubnov
中科院分区:
文献类型:
--
作者:
V. Bubnov
The known fundamental solution of the heat-conduction equation in the form of Poisson's integral is obtained by summing-up particular similarity solutions derived with the help of a similarity group. As these similarity solutions do not satisfy the initial data, then the integral condition is obtained from which the arbitrary constant of a general solution is determined. Then the solution in the form of Poisson's integral is shown to satisfy approximately the initial condition in the form of the discontinuous step function approximating the initial function. This is one of the drawbacks of the fundamental solution of the classical heat-conduction equation.The paradox on an infinite “heat propagation velocity” is discussed.Analysing the isotherm behaviour and using Green's theorem, the general non-linear wave equation is derived here in which the speed of isotherm propagation along the normal is used as an experimental parameter. The relationship between this speed and thermal diffusivity is shown. The different particular cases of this wave equation are studied. Some wave equation solutions are shown to correspond to those of the non-linear parabolic equation.Then, the derivation is given of the wave heat conduction equation from the point of view of molecular kinetic considerations. The conception on time relaxation is generalized using the Maxwell method and taking into account the correlation between components of a heat velocity of atoms of molecules.