On the Effective Thermal Diffusivity of Macroscopic Heterogeneous Two Phase Materials

  • B. Schulz


The idea of an effective diffusivity of a composite normally requires the assumption that the composite is quasihomogeneous, i.e. the size of the individual particles of the phases is small compared with the size of sample. Using the laser flash technique it is investigated to what extent this assumption has to be fulfilled in defining an effective thermal diffusivity for heterogeneous materials. Samples of the following geometry were examined: disc-shaped pores in metals, copper spheres in Plexiglass, Plexiglass discs in metals and molten materials in non-transparent capsules. The results are interpreted on the background of the model of the effective diffusivity, where the encapsulated phase is characterized by a shape factor and a definite orientation with respect to the heat flow in the sample.


Effective Diffusivity Effective Thermal Conductivity Heterogeneous Sample Laser Flash Molten Material 
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Copyright information

© Purdue Research Foundation 1985

Authors and Affiliations

  • B. Schulz
    • 1
  1. 1.Institut für Material — und FestkörperforschungKernforschungszentrum KarlsruheKarlsruheDeutschland

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