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Ultimate temperature of pulse tube cryocoolers
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Kittel, Peter |
| Copyright Year | 2009 |
| Description | An ideal pulse tube cryocooler using an ideal gas can operate at any temperature. This is not true for real gases. The enthalpy flow resulting from the real gas effects of He-3, He-4, and their mixtures in ideal pulse tube cryocoolers puts limits on the operating temperature of pulse tube cryocoolers. The discussion of these effects follows a previous description of the real gas effects in ideal pulse tube cryocoolers and makes use of models of the thermophysical properties of He-3 and He-4. Published data is used to extend the analysis to mixtures of He-3 and He-4. The analysis was done for pressures below 2 MPa and temperatures below 2.5 K. Both gases and their mixtures show low temperature limits for pulse tube cryocoolers. These limits are in the 0.5-2.2 K range and depend on pressure and mixture. In some circumstances, even lower temperatures may be possible. Pulse tube cryocoolers using the two-fluid properties of dilute 3He in superfluid He-4 appear to have no limit. |
| File Size | 297454 |
| Page Count | 8 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20100002761 |
| Archival Resource Key | ark:/13960/t41s1sd2c |
| Language | English |
| Publisher Date | 2009-06-26 |
| Access Restriction | Open |
| Subject Keyword | Fluid Mechanics And Thermodynamics Enthalpy Helium Isotopes Cryogenic Cooling Ideal Gas Real Gases Superfluidity Thermophysical Properties Low Temperature Operating Temperature Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
