Identifying a Superfluid Reynolds Number via Dynamical Similarity

Reeves, M.T.; Billam, T.P.; Anderson, B.P.; Bradley, A.S.

Abstract

The Reynolds number provides a characterization of the transition to turbulent flow, with wide application in classical fluid dynamics. Identifying such a parameter in superfluid systems is challenging due to their fundamentally inviscid nature. Performing a systematic study of superfluid cylinder wakes in two dimensions, we observe dynamical similarity of the frequency of vortex shedding by a cylindrical obstacle. The universality of the turbulent wake dynamics is revealed by expressing shedding frequencies in terms of an appropriately defined superfluid Reynolds number, Res, that accounts for the breakdown of superfluid flow through quantum vortex shedding. For large obstacles, the dimensionless shedding frequency exhibits a universal form that is well-fitted by a classical empirical relation. In this regime the transition to turbulence occurs at Res≈0.7, irrespective of obstacle width.

Citation

Reeves, M., Billam, T., Anderson, B., & Bradley, A. (2015). Identifying a Superfluid Reynolds Number via Dynamical Similarity. Physical Review Letters, 114(15), Article 155302. https://doi.org/10.1103/physrevlett.114.155302

• Journal Article Type: Article
• Acceptance Date: Mar 3, 2015
• Publication Date: Apr 16, 2015
• Deposit Date: Jun 26, 2015
• Publicly Available Date: Jun 30, 2015
• Journal: Physical Review Letters
• Print ISSN: 0031-9007
• Electronic ISSN: 1079-7114
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 114
• Issue: 15
• Article Number: 155302
• DOI: https://doi.org/10.1103/physrevlett.114.155302
• Public URL: https://durham-repository.worktribe.com/output/1435369
• Related Public URLs: http://arxiv.org/abs/1411.5742