Tracer particle generation in superfluid helium through cryogenic liquid injection for particle image velocimetry (PIV) applications

This paper reports the first experimental study of liquid neon injection into superfluid helium (He II) through a plain orifice atomizer to explore different means of introducing micron-size tracer particles into a He II bath for particle image velocimetry (PIV) applications. The obtained results verify that the direct injection of liquid neon into He II introduces seed particles into the He II bath. It is also demonstrated that the particle sizes can be controlled by changing the pressure above the injected liquid. Additionally, the size distribution of the particles is calculated from the PIV results through the use of the correlations to the standard drag curve.