摘要
提出了超常热、质传递过程的“瞬态薄层”模型———在超常热、质传递条件下 ,紧靠介质内受热或质扰动的位置 ,存在一“薄层”区域 ,该薄层内的热传导或质量传递必须考虑非经典 (非傅立叶或非费克 )传递效应 ,在薄层外、介质内其他部分的热、质传递仍近似符合经典热、质传递定律 (傅立叶和费克定律 ) ;“瞬态薄层”内的非经典传递效应只可能在热、质扰动过后的极短瞬时存在 .在分析介质内的非傅立叶导热行为的同时 ,根据热、质传递的可类比性得到非经典质量传递“瞬态薄层”的厚度与质松驰时间、质扩散系数以及质量扰动的强度和瞬时性强弱的定性相关关系 .
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.
出处
《中国科学院研究生院学报》
CAS
CSCD
2000年第1期28-35,共8页
Journal of the Graduate School of the Chinese Academy of Sciences
基金
国家自然科学重点基金! (5 9736 130 )
中国科学院"九五"基础性研究重大项目基金! (KJ95 1 B1 70 4)
国家重点基础研究发展规划项
