Quantitative method for measuring heat flux emitted from a cryogenic object
Abstract
The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined. The total heat flux from the heat-fluxing object is determined as a function of this difference between these temperatures. In certain applications, the technique can be used to optimize thermal design parameters of cryogenic electronics, for example, Josephson junction and infrared sensing devices.
- Inventors:
- Issue Date:
- OSTI Identifier:
- 6278578
- Patent Number(s):
- 5193909
- Application Number:
- PPN: US 7-881980
- Assignee:
- Dept. of Energy, Washington, DC (United States)
- DOE Contract Number:
- AC04-76DP00789
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 12 May 1992
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COOLING SYSTEMS; DESIGN; HEAT FLUX; MEASURING METHODS; JOSEPHSON JUNCTIONS; RADIATION DETECTORS; CRYOGENICS; HELIUM; INFRARED RADIATION; NOISE; OPTIMIZATION; POWER LOSSES; SUPERFLUIDITY; TEMPERATURE CONTROL; TEMPERATURE DEPENDENCE; TEMPERATURE MEASUREMENT; TRANSITION TEMPERATURE; CONTROL; ELECTROMAGNETIC RADIATION; ELEMENTS; ENERGY LOSSES; ENERGY SYSTEMS; FLUIDS; GASES; JUNCTIONS; LOSSES; MEASURING INSTRUMENTS; NONMETALS; PHYSICAL PROPERTIES; RADIATIONS; RARE GASES; SUPERCONDUCTING JUNCTIONS; THERMODYNAMIC PROPERTIES; 661210* - Cryogenics- (1992-)
Citation Formats
Duncan, R V. Quantitative method for measuring heat flux emitted from a cryogenic object. United States: N. p., 1993.
Web.
Duncan, R V. Quantitative method for measuring heat flux emitted from a cryogenic object. United States.
Duncan, R V. Tue .
"Quantitative method for measuring heat flux emitted from a cryogenic object". United States.
@article{osti_6278578,
title = {Quantitative method for measuring heat flux emitted from a cryogenic object},
author = {Duncan, R V},
abstractNote = {The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined. The total heat flux from the heat-fluxing object is determined as a function of this difference between these temperatures. In certain applications, the technique can be used to optimize thermal design parameters of cryogenic electronics, for example, Josephson junction and infrared sensing devices.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1993},
month = {3}
}