Active Thermal Insulation of High-Temperature Surfaces of Technological Equipment Based on Packed Beds

Models of heat transfer in infiltrated packed beds of large low-heat conducting particles that are used as active thermal insulation of high-temperatures surfaces of technological equipment have been developed. A criterion of active thermal insulation involving main geometrical and thermal parameters of the infiltrated packed bed has been introduced. The effect of packed bed nonisothermicity and gas compressibility on the resistance of active thermal insulation has been investigated. An approximation dependence of the resistance of the bed on its geometrical, hydrodynamic, and thermal characteristics has been obtained. Cooling of a cap gas distributer via active insulation has been studied.