A Simple Realization Method for Predicting Thermal Conductivity of Periodic Composites by Progressive Homogenization

Abstract

The invention discloses a simple implementation method for predicting the periodical composite material thermal conductivity coefficient in a gradual and homogeneous manner. A unit cell finite element model is established through commercial finite element software; the material thermal conductivity coefficient of the unit cell finite element model is set; the unit cell finite element model is subjected to finite element mesh dividing to obtain node and unit information of the unit cell finite element model; an initial temperature field is determined according to node coordinate values of the unit cell finite element model; and the periodical composite material thermal conductivity coefficient is calculated. According to the simple implementation method, the performance predication for any complex periodical structure can be realized by the unit type and any combination provided by the commercial finite element software; an integration operation is required for each unit when a right end load of a temperature gradient field control equation is solved by the original homogenization method; the original homogenization method, different from a conventional finite element format, can be realized by requiring corresponding programming, so that the original homogenization method is relatively high in threshold in use; however, the simple implementation method provided by the invention enables the homogenization method to perform direct calculation through the existing commercial finite element software, so that the difficulty in use is greatly lowered.

Description

technical field

[0001] The invention relates to a new finite element formula for progressively homogenizing and predicting the thermal conductivity of periodic composite materials and a realization method based on commercial finite element software. It belongs to the field of performance characterization of composite materials. Background technique

[0002] Composite materials are widely used in the engineering field because of their excellent material properties. The design and use of composite material structures require us to have a full understanding of the properties of composite materials. Thermal conductivity is one of the important aspects. For the prediction of thermal conductivity of composite materials, there are usually methods such as analytical model, representative voxel method and homogenization. In order to obtain a relatively simple analytical expression, the analytical model usually needs to make some unrealistic assumptions, which will lead to large err...

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