Stability of flow and the transition to turbulence around a quartz tuning fork in superfluid He-4 at very low temperatures

Bradley, D. I. and Fear, M. J. and Fisher, Shaun and Guenault, A. M. and Haley, R. P. and Lawson, C. R. and Pickett, G. R. and Schanen, R. and Tsepelin, V. and Wheatland, L. A. (2014) Stability of flow and the transition to turbulence around a quartz tuning fork in superfluid He-4 at very low temperatures. Physical review B, 89 (21). ISSN 1098-0121

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Abstract

We have studied the transition between pure potential flow and turbulent flow around a quartz tuning fork resonator in superfluid He-4 at millikelvin temperatures. Turbulent flow is identified by an additional drag force on the fork prongs due to the creation of quantized vortices. When driven at a constant driving force amplitude, the transition to turbulence causes an abrupt decrease in the velocity amplitude of the prongs. For a range of driving forces, continuous switching is observed between the two flow states. We have made a statistical study of the switching characteristics and of the lifetimes of the unstable states. We find a characteristic velocity nu(star) which separates quasistable turbulent flow at higher velocities and quasistable potential flow at lower velocities. We show that the potential-to-turbulent flow transition is driven by random processes involving remanent vortices pinned to the prongs.

Item Type:
Journal Article
Journal or Publication Title:
Physical review B
Additional Information:
Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Published by the American Physical Society
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ID Code:
70110
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Deposited On:
25 Jul 2014 09:25
Refereed?:
Yes
Published?:
Published
Last Modified:
03 Jun 2020 02:24