Consideration on Heat Transfer Mechanism and Thermal Conductivity of Thermal Insulation Brick

摘要

The objects of this study are to estimate the thermal conductivity of thermal insulation brick and to examine heat transfer mechanism in it. The specimen to be considered is high aluminum oxide (Al_2O_3) insulation brick having 0.2 volume fraction of pore. The standard (actual) value for comparison with predicted values is 0.858 [W/(mK)] at 350[℃]. The recommended values of thermal conductivity of Al_2O_3 and gases filled in bricku27s pore are obtained by TPRC and JSME Heat Transfer Handbook, respectively. The predict equations of thermal conductivity selected in this paper are the ones containing spherical particle into the matrix. There are considerable differences between predicted values and actual data. Therefore, two dimensional simple model as first approximation is proposed to investigate on bending and narrow down phenomena of heat flow. The numerical analysis based on finite difference method is used to obtain the solution of heat conduction equation. The results acquired by this scheme are not enough in quantitatively, but a few interest knowledge are found for next report.