1 / 20

Contents

Contents. Progress at the large scale CO 2 system, Results of the small scale CO 2 system in the cryolab. CO 2 - Large scale system. Joao Noite, Lukasz Zwalinski, Torsten Koettig. CO 2 - Large scale system. CO 2 - Large scale system. CO 2 - Large scale system.

almira
Download Presentation

Contents

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. Contents • Progress at the large scale CO2 system, • Results of the small scale CO2 system in the cryolab.

  2. CO2 - Large scale system Joao Noite, Lukasz Zwalinski, Torsten Koettig

  3. CO2 - Large scale system

  4. CO2 - Large scale system

  5. CO2 - Large scale system • Location in 158: • - Commissioning of the system at 25°C, • Possible mass flow rate 1...15 g/s, • Run only at ambient temperature • at the moment, • Next step => accumulator to vary Tsat. Joao Noite, Lukasz Zwalinski, Torsten Koettig

  6. CO2 – Small scale system Small scale system in the cryolab CERN: Test section length: 300 mm, heated part: 150 mm • Measurement of the heat transfer coefficient and pressure drop under variation of the following dependencies: • Vapor quality x • Heat flux q • Mass flux G • Saturation temperature Tsat Jihao Wu, Daniel Helmer

  7. CO2 - Small scale system Heat transfer coefficient in the flow map (Tsat=263 K, G=300 kg/m2s, q=15kW/m2)

  8. CO2 - Scanning the two-phase region Pressure drop in the flow map (Tsat=263 K, G=300 kg/m2s, q=15kW/m2) Pressure drop [mbar] Mass flux [kg/m2s] Vapor quality x

  9. CO2 - Scanning the two-phase region • Measurement of the heat transfer coefficient and pressure drop under variation of the following dependencies: • Vapor quality x • Heat flux q • Mass flux G • Saturation temperature Tsat

  10. CO2 - Scanning the two-phase region Heat flux dependency of the heat coefficient (T=263 K, G=400 kg/m2s)

  11. CO2 - Scanning the two-phase region Heat flux dependency of the pressure drop(T=263 K, G=400 kg/m2s)

  12. CO2 - Scanning the two-phase region • Measurement of the heat transfer coefficient and pressure drop under variation of the following dependencies: • Vapor quality x • Heat flux q • Mass flux G • Saturation temperature Tsat

  13. CO2 - Scanning the two-phase region Mass flux dependency of the heat coefficient (T=263 K, q=7.5 kW/m2)

  14. CO2 - Scanning the two-phase region Mass flux dependency of the pressure drop (T=263 K, q=7.5 kW/m2)

  15. CO2 - Scanning the two-phase region • Measurement of the heat transfer coefficient and pressure drop under variation of the following dependencies: • Vapor quality x • Heat flux q • Mass flux G • Saturation temperature Tsat

  16. CO2 - Scanning the two-phase region Temperature dependency of the heat coefficient (q=15 kW/m2, G=300 kg/m2s)

  17. CO2 - Scanning the two-phase region Temperature dependency of pressure drop (q=15 kW/m2, G=300 kg/m2s)

  18. Resume • Reliable test setup to determine heat transfer and pressure drop, • Measurements in the whole two phase region are done, • Influences of mass flux, heat flux and saturation temperature. Paper will be submitted to Int. Journal of Heat and Mass Transfer

  19. CO2 - Small scale system Instabilities Observed instabilities: J-T expansion into subcooled liquid or x<3% oscillations occur Oscillations are amplified reaching the dryout at around 75 % vapor quality Temperatures below -34 °C

More Related