Modeling of the Relationship between Pore Size Distribution and Thermal Conductivity of Corundum Based Castables

Four corundum based castables with different pore size distribution were prepared. Their apparent porosity, pore size distribution and thermal conductivity at 600 degrees C and 1000 degrees C were tested. Thermal conductivity of the castable specimens was predicted based on Maxwell model. Results show that there is a great difference between predicted value and experimental value. The Maxwell model was modified by the volume percent of micro pore. The model of the relationship among thermal conductivity, apparent porosity and pore size distribution was established, and then it was verified subsequently. The result shows that the predicted value from the modified model and experimental value shows good consistency. The deviation range between the predicted value and experimental value is about 7%similar to 25%. Radiation heat transfer is the main cause that leads to the above deviation.