Analytical Methods for Heat Conduction in Composites and Porous Media
Analytical Methods for Heat Conduction in Composites and Porous Media
复制标题
复合材料和多孔介质中热传导的分析方法
DOI:
10.1002/9783527621408.ch5
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发表时间:
2008
影响因子:
0.8
通讯作者:
S. Rogosin
中科院分区:
文献类型:
--
作者:
V. Mityushev;E. Pesetskaya;S. Rogosin
The goal of this chapter is to describe analytical methods applied to the study of steady heat conduction in various types of composites and porous media. We present several analytical formulas for the effective (macroscopic) conductivity tensor which are deduced by using different approaches based on the recent results in the theory of partial differential equations and complex analysis. The study of effective characteristics has recently become a separate subject with its own philosophy and machinery. Composites and porous media differ by geometry and by the type of physical problems that appear. For composites, the most popular are problems of conductivity, elasticity, elastoplasticity and thermoelasticity (eg Refs.[1–4]), but for porous media, problems of fluid mechanics are mostly studied (eg Refs.[5–9]).The analytical approach to the study of heat conduction allows us to unify partly the theory of the effective thermal properties in composite materials and porous media. In the present chapter, pure steady conductivity problems are considered when the filler of pores (fluid or gas) is static. Such problems are benchmarks of heat and mass transfer problems of the mechanics of porous media [10]. The main attention throughout this chapter will be paid to analytic or constructive, or closed form solutions to the above mentioned problems. Different interpretations can be given to such a notion. For us to get an analytical solution means to find the formula which contains a finite set of elementary and special functions, compositions, integrals, derivatives and even series. Besides, all objects in such a formula have to have a precise meaning (for instance, the type of the convergence of integrals and series should be described). Last, the domains of parameters, as well as all functions, integrals, etc., have to be explicitly determined. It will also be shown also that they (or their intersections, if necessary) are nonempty. This approach is slightly nontraditional. In classic books, it is supposed that series do not form closed form solutions, but special functions do. It leads to certain misunderstandings since not