Non-fourier is applied in the research of thermal shock,with the finite speed of heat propagation is considered in the situations involving very short times or extreme thermal gradients,an effective method is presented for gaining the distribution of the temperature field and the exact solution for the transient waves caused by thermal shock,the response and distribution of thermodynamic stresses in a hollow cylinder are also solved by means of the analytical method.
This study simulates the effects of different temperature pulse inlet conditions on non Fourier heat conduction problem, and numerically predicts different non Fourier heat conduction characters produced by different pulse types and different pulse frequencies, respectively.
The mathematical model of universal Fourier heat conduction law has been discussed in this paper,which is based on the hyperbolic heat conduction equation of non\|Fourier heat conduction law,and an analytical solution of a semi\|infinite body has been derived under the first boundary condition.
Hyperbolic non Fourier heat conduction in a spherical medium under time varying pulse heating was analyzed. The nondimensional forms of heat conduction equation, boundary conditions and initial conditions of such a rapid transient heat conduction problem were proposed. The analytical expression of transient temperature distribution in the sphere was obtained using Laplace transform technique. As an example, the propagation of temperature in the sphere under square wave heat pulse was simulated. The results...
Hyperbolic non Fourier heat conduction in a spherical medium under time varying pulse heating was analyzed. The nondimensional forms of heat conduction equation, boundary conditions and initial conditions of such a rapid transient heat conduction problem were proposed. The analytical expression of transient temperature distribution in the sphere was obtained using Laplace transform technique. As an example, the propagation of temperature in the sphere under square wave heat pulse was simulated. The results show that such a rapid transient heat conduction problem has the following characteristics compared with the common Fourier case:(1) There is a time lagging response in temperature from the surface to the interior. (2) The variation of temperature inside the sphere is discontinuous due to the discontinuous time varying surface heat flux.(3) The surface heat pulse will cause the peak pulse of temperature in the interior of the materials.(4) The significance of non Fourier effects in heat conduction mainly depends on the thermal imposed time, the thermal relaxation time and characteristic length of the materials.
An“instantaneous thin layer”model for transnormal heat or mass transfer is brought forward in this paper.For transnormal heat or mass transfer,there is an interface existing in the medium,which divides the object into two parts:the “instantaneous thin layer”,which is a thin Layer region around the heat or mass disturbance position,and the other part of the object. Heat or mass transfer in the “thin layer”is governed by the transnormal law (non Fourier or non Fick law)and that in the other part is still complied...
An“instantaneous thin layer”model for transnormal heat or mass transfer is brought forward in this paper.For transnormal heat or mass transfer,there is an interface existing in the medium,which divides the object into two parts:the “instantaneous thin layer”,which is a thin Layer region around the heat or mass disturbance position,and the other part of the object. Heat or mass transfer in the “thin layer”is governed by the transnormal law (non Fourier or non Fick law)and that in the other part is still complied with the traditional law (Fourier or Fick law) approximatively.Heat or mass transfer at the boundary surface of the“thin layer”region is satisfied to the continuous boundary condition(i.e.the fourth kind boundary condition).An example of one dimensional transnormal heat conduction,resulted from a rectangular pulsed energy souce,is presented in this paper.The hyperbolic non Fourier heat conduction equation is employed to describe this transnormal thermal case and the finite diference method (FDM)combined with MacCormack's predictor corrector scheme is used to solve it.The correlativity of the thickness of the thermal“instantaneous thin layer”to the thermal relaxation time,thermal diffusivity and the thermal disturbing source(including its strength and instantaneity) is obtained.Moreover,according to the analogy of the mass and heat transfer,the correlativity of the thicknes of the mass“instantaneous thin layer”to the mass relaxation time,mass diffusivity and the mass disturbing source is obtained too.
Mathematical model of laser beam irradiates the surface of a water-containing porous materials is presented, and related numerical method is used to solve the equations. The results indicate that heat and mass transfer is different from the description of classical heat and mass transfer theories, non-Fickian effects is more obvious than non-Fourier effects and should be taken into account as higher power laser beam irritates the surface of higher moisture content materials.
非傅立叶
non-fourier
查询“非傅立叶”译词为用户自定义的双语例句
相关查询
2008 CNKI－中国知网