2. Progress at the large scale CO2 system,
Contents
Progress at the large scale CO2 system,
Results of the small scale CO2 system connected to the
large scale system.

3. Possible mass flow rate
CO2 - Large scale system
Location in 158:
Temperature range
-27°C to 25 °C,
Possible mass flow rate
g/s,
Self made accumulator,
Measurements with:
- CMS 5.5m tube and
- CL small scale system.
Joao Noite,
Lukasz Zwalinski,
Jihao Wu,
Petra Janickova,
Torsten Koettig

4. CO2 - Large scale system

5. CO2 - Large scale system

6. Large scale system in Bldg. 158 at CERN: Test section length: 5.5 m
CO2 – CMS 5.5 m tube
Large scale system in Bldg. 158 at CERN:
Test section length: 5.5 m
Jani Turunen and Joao Noite
Measurement of the temperature distribution along the tube in dependency of:
heat load
mass flow
comparison of the dependencies vs vapor quality

7. CO2 - Large scale system

8. CO2 - Large scale system

9. 5.5 m CMS tube, 1.424 mm diameter, varied heat input and mass flow
CO2 - Large scale system
5.5 m CMS tube, mm diameter, varied heat input and mass flow
Mass flow
(g/s)
Heat input
(W)
1.5
2.1 70
100
120
150

10. Small scale system in the cryolab CERN:
CO2 – Small scale system
Small scale system in the cryolab CERN:
Test section length: 300 mm, heated part: 150 mm
Petra Janickova, Jihao Wu and Torsten Koettig
Measurement of the heat transfer coefficient and pressure drop under variation of the following dependencies:
Vapor quality x
Mass flux G
Saturation temperature Tsat

11. CO2 - Small scale system

12. CO2 - Small scale system
Heat transfer coefficient – Comparison of different supply systems

13. CO2 - Small scale system
Pressure drop – Comparison of different supply systems

14. CO2 - Small scale system
Alternative pressure drop determination:
temperature difference T4-T8 in the two phase region => Δp4-8 Δp
outlet
inlet

15. CO2 - Small scale system

16. CO2 - Small scale system

17. CO2 – Small scale system
Heat transfer coefficient - Mass flux dependency
G= 502 kg/m2s
G= 628 kg/m2s
G= 816 kg/m2s
G= 1005 kg/m2s

18. CO2 – Small scale system
Pressure drop gradient - Mass flux dependency
G= 502 kg/m2s
G= 628 kg/m2s
G= 816 kg/m2s
G= 1005 kg/m2s

19. Paper is in review process Int. Journal of Heat and Mass Transfer
Resume
Large scale system in operation,
Small scale system is connected to the large scale system,
Deviation in heat transfer and pressure drop at different locations,
Possible influences of pressure oscillations created by the membrane-
pump.
Paper is in review process
Int. Journal of Heat and Mass Transfer

20. CO2 - Large scale s. incl. small scale s.
Top-lid dismounted and turned
CO2 heat exchanger spiral
Heat exchanger vessel
Small scale system connected
via flexible pipes

21. CO2 - Large scale s. incl. small scale s.
Electrical connection
box of the heater
Corrosion by inleaking water –
glykol mixture
3 heater loops - one failed => disconnected
Dummy load vessel - view from the bottom