Turbulence in He II Generated by Superflow

We report experimental investigations of He II turbulence and its decay, generated by pure superflow through a channel of square crossection. Both ends of the channel are covered by sintered‐silver superleaks, which prevent any net normal fluid flow through the channel. The steady‐state turbulence is generated by applying a power to the heater immersed in He II in a volume adjacent to one of the superleaks having an outlet above the helium bath level in the glass cryostat. When the power is switched off, the superflow through the channel and the vortex line density in the middle of the channel decay. The steady‐state vortex line density and the form of its decay is continuously measured by second sound attenuation and analyzed within available theoretical models.