Storage and transfer of cryogenic liquid require very low heat leaks so as to prevent evaporation loss of cryogen for various low-temperature applications including cryogenic fuel storage for space missions as propellant. Multilayer insulation provides the most effective thermal protection available for cryogenic storage and transfer systems. Heat is transferred across the annular space of a vacuum-insulated vessel mainly by radiation from the outer vessel at room temperature to the inner vessel at cryogenic temperature as an annular space vacuum prevents heat transfer by solid conduction and gaseous convection.

In this context, an attempt has been made to study the performance of aluminized mylar sheets with fiberglass paper as spacers for the multilayer insulation system. The paper described relevant heat transfer equations for computing heat loss and the optimum number of layers of radiation shields required for cryogenic storage vessels. A 3-liter cryogen vessel is developed by wrapping the inner vessel with 32 layers of aluminized sheets with nonconducting spacers and evacuating the space between the inner vessel and the outer jacket. The indigenously built cryogenic Dewar vessel is filled with liquid nitrogen and the evaporating rate is studied. The results are encouraging in terms of holding time.