Thermal Energy Storage Demonstration Unit for Vuilleumier Cryogenic Cooler.
Abstract
A thermal energy storage unit for a High Capacity (Hi-Cap) Vuilleumier Cryogenic Cooler was designed, built and performance tested. The unit was specified to have a sufficient thermal energy storage capacity for supplying one hot cylinder of the Hi-Cap Cryogenic cooler for 18 minutes with 650W of power at a maximum power loss of 5 percent through the insulation. The discharge of the unit was to take place at a nominal temperature of 1250 F + or - 25 F. A thermal energy storage (TES) unit with the hot cylinder of the Vuilleumier cooler was designed with a total thermal capacity of 737100 joules. The thermal energy is stored in the form of latent heat of fusion in the eutectic salt composed of lithium fluoride, magnesium fluoride and potassium fluoride. The unit was insulated with a multiple radiation shield super-insulation consisting of alternate layers of 0.020-inch thick Fiberfrax paper without binder and 0.001-inch Nickel foil. The insulation is maintained in a vacuum inside of an insulation container. The TES unit is instrumented for temperature control with two chromel alumel thermocouples. The single resistance temperature detector (RTD) failed during testing and is inoperative. All specified goals for the operation of the TES unit were achieved except for the maximum thermal loss through the insulation which exceeded the goal by 8W. This deviation could easily be corrected by interposing a condution insulation at the thermal ring of the unit. The report presents all pertinent design and fabrication information.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1977
- Accession Number
- ADA054466
Entities
People
- Robert Richter
Organizations
- Xerox