An experiment to study forced flow superfluid helium (He II) at high Reynolds
number has been recently developed at the NHMFL. The liquid is pushed from a
bellows pump through a 1 m long, 9.8 mm inside diameter smooth tube test section
to attain a maximum velocity of 18 m/s and a Reynolds number up to 2 x 10-7.
The test section is instrumented with eight bare chip thermometers, a heater and
a differential pressure transducer. Measurements of pressure drop have been
performed to determine the friction factor for Reynolds number exceeding 10-7.
These are compared to results from previous forced flow experiments at lower
velocities and to some existing correlations. The temperature rise in He II forced
flow, due to the isenthalpic expansion in the test section, has also been measured
for velocities between 0.5 m/s and 16 m/s. These temperature profiles are related
to the Joule-Thomson coefficient. The heater, positioned in the middle of the test
section, allows heat transfer measurements and can be used as a thermal flow
meter.
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