Home > Research > Publications & Outputs > Transition to turbulence for a quartz tuning fo...

Associated organisational unit

Electronic data

Text available via DOI:

View graph of relations

Transition to turbulence for a quartz tuning fork in superfluid He-4

Research output: Contribution to journalJournal article

<mark>Journal publication date</mark>09/2009
<mark>Journal</mark>Journal of Low Temperature Physics
Issue number3-6
Number of pages16
Pages (from-to)116-131
<mark>Original language</mark>English


We have studied the resonance of a commercial quartz tuning fork immersed in superfluid He-4, at temperatures between 5 mK and 1 K, and at pressures between zero and 25 bar. The force-velocity curves for the tuning fork show a linear damping force at low velocities. On increasing velocity we see a transition corresponding to the appearance of extra drag due to quantized vortex lines in the superfluid. We loosely call this extra contribution "turbulent drag". The turbulent drag force, obtained after subtracting a linear damping force, is independent of pressure and temperature below 1 K, and is easily fitted by an empirical formula. The transition from linear damping (laminar flow) occurs at a well-defined critical velocity that has the same value for the pressures and temperatures that we have measured. Later experiments using the same fork in a new cell revealed different behaviour, with the velocity stepping discontinuously at the transition, somewhat similar to previous observations on vibrating wire resonators and oscillating spheres. We compare and contrast the observed behaviour of the superfluid drag and inertial forces with that measured for vibrating wires.

Bibliographic note

The final publication is available at Springer via http://dx.doi.org/10.1007/s10909-009-9901-3