Transfer equipment, cryogenic gases

It is felt that the analytical method presented here is distinctly superior to any of the empirical methods for estimating gas consumption, such as the so-called "saturation rule." Application of the analytical method, however, is somewhat more difficult. The method should be suitable for all tank systems that use cryogens (such as hydrogen, oxygen, nitrogen, fluorine, carbon monoxide and neon) and that are equipped with a gas diffuser to prevent direct jetting of the gas into the liquid. In addition, the method is set up so that large variations in system operation may be incorporated by a person reasonably well versed in the principles of thermodynamics and heat transfer. 

Because of this low bulk density and inherently low heat capacity of the materials used in the insulating system, the application of NRC insulation to cryogenic equipment or apparatus offers not only an efficient reduction of the heat leak, but also a remarkably low additional heat capacity, which results in drastic decrease of cool-down losses. At the same time, the low heat capacity makes it possible to reach thermal equilibrium in much shorter time than is possible with other types of multilayer insulations with bulk weights three to six times higher. This is of great importance in the consideration of air-borne or space-vehicle applications. The low thermal capacity of the insulation makes feasible and economically justifiable the use of this insulation in liquid-gas transfer lines. 

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