title: Three-dimensional inverse energy transfer induced by vortex reconnections.
abstract: In low-temperature superfluid helium, viscosity is zero and vorticity takes the form of discrete vortex filaments of fixed circulation and atomic thickness. We present numerical evidence of three-dimensional inverse energy transfer from small length scales to large length scales in superfluid turbulence generated by a flow of vortex rings. We argue that the effect arises from the anisotropy of the flow, which favors vortex reconnections of vortex loops of the same polarity, and that it has been indirectly observed in the laboratory. The effect opens questions about analogies with related processes in ordinary turbulence.
authors.affiliation: School of Mathematics and Statistics, University of Glasgow, Glasgow, G12 8QW, United Kingdom.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Baggaley
authors.affiliation: Joint Quantum Centre Durham-Newcastle and School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom.
authors.forename: Carlo F
authors.initials: CF
authors.lastname: Barenghi
authors.affiliation: Joint Quantum Centre Durham-Newcastle and School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom.
authors.forename: Yuri A
authors.initials: YA
authors.lastname: Sergeev