Thermal insulation for high temperature use, (2)

Concerning the internal insulator used at high temperature such as high-temperature gas cooled reactors, the gas evolved from insulator is first described. Then, the instances of the internal insulation structure and also their thermal insulation characteristics are explained. Finally, the desirable insulation structures are presented. Rise in the thermal conductivity of insulation structures is caused by natural convection and bypass flow in the gap, as well as radiation heat. So, the countermeasures to them are necessary. (Mori, K.)