Statistical Measurement of Counterflow Turbulence in Superfluid Helium-4 Using $$\hbox {He}_2^*$$ Tracer-Line Tracking Technique

Abstract

We report preliminary results of a systematic study of the flow of normal fluid component in steady-state quantum turbulence in thermal counterflow of superfluid \(^{4}\hbox {He}\) using a high-precision flow visualisation technique based on the tracking of thin lines of \(\hbox {He}_2^{*}\) molecular tracers. Non-trivial profiles of mean velocity and turbulent fluctuation across the channel are observed with complicated temperature- and heat flux-dependencies. Mean turbulence intensity, however, depends on velocity only very weakly and is controlled primarily by the temperature.