1 / 17

Outlines

Adaptation of refrigeration compressors for Joule-Thomson cryocoolers fed with gas mixtures Agnieszka Piotrowska, Maciej Chorowski, Pawel Dorosz Wroclaw University of Technology, Poland CEC-ICMC 2015, June 29th, 2015. Outlines. Joule-Thomson coolers – open system

rblais
Télécharger la présentation

Outlines

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Adaptation of refrigeration compressors for Joule-Thomson cryocoolers fed with gas mixturesAgnieszka Piotrowska, Maciej Chorowski, Pawel DoroszWroclaw University of Technology, PolandCEC-ICMC 2015, June 29th, 2015

  2. Outlines • Joule-Thomson coolers – open system • Joule-Thomson coolers supplied with gas mixture – closed system • Refrigeration compressors • The possibility of the compressor cooling • Conclusions

  3. Joule-Thomson coolers – open system • Simple construction • No moving parts working at low temperatures • Short start-up time High workingpressure, min. 80 bar for N2, up to inversionpressure Lowthermodynamicefficiency Limited workingtime (need of pressure tank replacement)

  4. Joule-Thomson coolers J-T coolers Micro capacity below 1 W Low capacity up to 10 W Medium capacity up to 50 W Cooling power: Wroclaw University of Technology, Poland CLOSED SYSTEM REQUIRED (reduction of working pressure) University of Twente, Netherlands

  5. Joule-Thomson cooler – closed system NITROGEN HEAT EXCHANGER AZOT AFTERCOOLER JT VALVE HEAT EXCH. COMPRESSOR MIXTURE MIESZANINA

  6. J-T cooler with hermetic piston compressor COMPRESSOR ELEMENTS ELECTRIC MOTOR

  7. Compression process Poisson equation Nitrogenk = 1.40 Methanek = 1.31 Ethanek = 1.19 Propanek = 1.13 I-butanek = 1.10 Mixturek = (1.10 - 1.40)

  8. Compressor test stand aftercooler throttling valve compressor

  9. Test results Nitrogen Methane Ethane Propane I-butane 5-components mixture

  10. Solutions of the compressor cooling Compressor located in the stream of theafter-cooler air - refrigeration technology v

  11. Hermetic compressors Calculation results of the required compressor surface Compressors: Danfoss VTZ serie nitrogen mixture

  12. Solutions of the compressor cooling Process modification To decrease inlet temperature of the working mixture:

  13. DTexpected = 22K Process modification Test results: DTmeasured = 6 K

  14. Solutions of the compressor cooling Modification of the construction Additionalcooling of the oil Outlet temperatureof gas – no additionalcooling Outlet temperatureof gas – additionalcooling Temperatureof the compressorshell – no additionalcooling Temperatureof the compressorshell – additionalcooling

  15. J-T coolers designed, manufactured and tested at WUT CRYOGENIC SUB-SYSTEM REFRIGERATION SUB-SYSTEM CRYOGENIC SUB-SYSTEM REFRIGERATION SUB-SYSTEM

  16. Test results – min. temp. 84 K Nitrogen 20%, Methane 30%, Ethane 10%, Propane 20%, I-butane 20% Temperature, K Pressure, bar Time, min

  17. Summary • Laboratory tests confirm the possibility of using refrigeration compressors for Joule-Thomson coolers supplied with gas mixtures. • Temperature of oil (directly depending on the final temperature of compressionprocess) is main limit factor. • Depending on the volumetric efficiency, the hermetic refrigeration compressors can be used without any modifications (for low efficiencies), for high efficiencies the modifications are the must.

More Related