The temperature function for the integral emissivity of certain materials below 300� K

Effective thermal conductivity of multilayer vacuum insulation as a function of its thickness

“…To check this assumption, we conducted a series of experiments on two calorimeters, one of which was described in [7], while the second is shown schematically in Fig. i.…”

“…The experiments required particularly high accuracy; accordingly, measures were taken to create identical conditions for all the specimens with respect to packing density and the level of the vacuum in the calorimetric cavity (2-4 9 10 -5 N/m2), while on the calorimeter of [7] the temperature at the guard ring was kept close to the temperature distribution in the specimen and the same annular gap was preserved between the specimen and the g~dard ring. We used the free packing density for insulation of type I and type III, namely, 28 sheets of foil per cm and 16 layers per cm, 5"…”

“…1. Diagram of calorimeter used for investigating insulation on model vessels: 1) vacuum chamber; 2) to pumping system; 3) cylindrical vessel (20 l ); 4) temperature compensators; 5) test insulation; 6)thermal insulation; 7) guard vessel; 8) screen; 9) to gas flow measuring system [7]. (free packing--7 sheets per cm).…”

“…The insulation of type II was tested at a packing density of I0 sheets per cm (free packing--7 sheets per cm). The insulation of types I and II was tested on the flat calorimeter of [7], that of type III on the calorimeter shown in Fig. i.…”