The TSF-f facility

Reynolds numbers of up to Re ~ 2 10 7 have been obtained on the test line in the 1.5 m long 30 mm inner diameter pipe with a mean flow velocity of 8 m/s. Stability better than 0.05K has been maintained over more than one hour. The R l achieved with the grid used in earlier experiments was about 400. The test line is presented below: it is equipped with hotwire anemometer, second sound vortex probe, acoustic scattering vorticity sensors and miniature pressure transducer. This line is today inserted at one end of the cold box of the refrigerator. The potential user can perform modifications to this line, and bring a new grid for example, or new sensors, for testing different turbulence properties

The TSF facility
The TSF facility enables to work in superfluid as well as in normal liquid helium. This is a large cryostat connected to the 400 Watt/1.8K refrigerator providing Re in the 10 7 range. *The 400W/1.8K Refrigerator* is in operation since 2004, when it achieved its nominal performances, namely 400W at 1.8K. The refrigeration power available ranks from 120W at 1.5K to 800W at 4.5K. All the temperature levels in between have been fully explored, and temperature can be adjusted in the range of 1.5 to 4.5 K continuously. Noisy screw compressors are located in a separate building, while the cold box stays in the main hall at the vicinity of the 26 m2 control room. Compared to the refrigerators available at CERN in the EuTuCHe@CERN, it offers the possibility to operate below the superfluid transition, down to 1.6K.

Refrigerator cold box (left) and warm compressor station (right)
Reynolds numbers of up to Re ~ 2 10 7 have been obtained on the test line in the 1.5 m long 30 mm inner diameter pipe with a mean flow velocity of 8 m/s. Stability better than 0.05K has been maintained over more than one hour. The R l achieved with the grid used in earlier experiments was about 400. The test line is presented below: it is equipped with hotwire anemometer, second sound vortex probe, acoustic scattering vorticity sensors and miniature pressure transducer. This line is today inserted at one end of the cold box of the refrigerator. The potential user can perform modifications to this line, and bring a new grid for example, or new sensors, for testing different turbulence properties

The experimental line @ TSF, with the grid (right), (bottom right) and the acoustic vorticity sensors	The future TSF cryostat and the refrigerator (top left)
In a very near future (mid 2009), the facility will be upgraded to bring more flexibility: A new cryostat will be installed, of larger dimensions and totally independent of the refrigerator. The space available in this upgraded TSF cryostat will roughly fit in a cylinder of 4m in height and 2 m in inner diameter. Lines providing liquid helium (normal or superfluid) and return pumping line and connections to cryogenic circulating pump are located at the bottom of this virtual cylinder, ensuring easy access for assembly of experimental inserts. An additional 20 000 liters liquid helium reservoir can be used during transient to boost the performances. This cryostat is presented above, with its connection to the refrigerator. Measurements available: the line is basically equipped with the detectors mentioned above, together with the electronics. Sensors dedicated to helium flow characterization are very small, which puts a heavy constraint on the mechanical and robustness aspects: all helium facilities will certainly take a great benefit from the results obtained in the JRA sto improve the sensors under cryogenic conditions. Users wishing to install new types of sensors in the TSF facility will need to test these sensors under similar cryogenic conditions before inserting their sensor in the TSF facility, which requires validation of the sensor before it is inserted in the extreme flow conditions in the test line. The second facility – the TSF-f (for TSF flexible) facility may help them to quickly validate these sensors.