Numerical method for studying temperature regimes of an inhomogeneous, structured body

DOI: 10.34759/trd-2020-115-19

Аuthors

Maskaykin V. A.

e-mail: vladimir.maskaykin@mail.ru

Abstract

In the aviation industry, thermal insulation mineral, fiberglass and polymer materials are employed for operation in extremely low temperature conditions. In certain cases, the structures, which perform the function of absolute isolation of gases from the external thermal impacts, are being created to obtain thermal isolation. If thermal isolation materials are being considered, the thermal isolation life span of such materials does not always satisfy the needs for temperature retention, and being regarded as a secondary subject operating in temperature regimes. The presented work solves two dimensional thermal conductivity problem of the element serving as a thermal insulator. It includes as well the study of heat transfer at the interaction of various materials between each other and their structural distribution in the element.

To solve the set problem, let us consider a conventionally selected segment (element) of the heat-insulating sheathing. The requirement consists in ensuring thermal isolation of the specified element in conditions of low temperatures by means of various materials and their structural distribution in the element. This problem solution is being performed by creating mathematical model and solving it numerically based on an implicit difference scheme. Computations of the mathematical model include the thermal conductivity problems of homogeneous body, a heterogeneous body with the structure of materials stratification, and the structure of the chess distribution of materials.

The results of the study show that the interaction of different materials in the element and the structural distribution of materials in the element play an important role in increasing thermal insulation properties. Interaction in heterogeneous bodies of various heat-insulating materials with each other has a low thermal insulation index, in contrast to the interaction of a heat-insulating material with the other, having the opposite thermal conductivity characteristics. An increase in thermal insulation in such body is accompanied by thermal insulation of a material with high thermal conductivity properties. A mutual substitution, “balancing” of the processes of thermal conductivity of materials with each other occurs.

Keywords:

thermal insulation, heterogeneous body, non-stationary thermal conductivity, thermal insulation materials, materials structuring in the body

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