Karp, G. S.
Engineer, General Electric Co., Valley Forge, Pa.
Lankton, C. S.
Consulting engineer, General Electric Co., Valley Forge, Pa.
Pages: 12 Published: Jan 1967
A guarded-hot-plate apparatus is employed by the General Electric Spacecraft Department for measuring the thermal conductance of multilayer insulation under vacuum conditions. The physical arrangement of the test apparatus, the range of operating temperatures, the methods employed in achieving these temperatures, and the method of measurement of heat flow and the method of control, are described. The basic sources of error in the measurement of the effective thermal conductivity, primarily the effects of pressure, temperature gradients, and edge effects, are identified, and results are given for some insulation configurations. The effect of the use of slit and unslit insulation on the measurement accuracy, the criteria for an equilibrium condition, and techniques for reducing the required test time are evaluated.
thermal insulation, cryogenics, thermal conductivity, low temperature, guarded hot plate, vaccum, heat transfer
Paper ID: STP47216S