Time-of-Flight Experiments of Vortex Rings Propagating from Turbulent Region of Superfluid 4He at High Temperature
- 69 Downloads
We report the time-of-flight of quantized vortex rings generated by a vibrating wire in superfluid 4He which contains normal fluid component. A cover box of vibrating wires and slow cooling of superfluid reduce the number of vortices attached to wire surfaces, enabling us to study vortex rings propagating from a turbulent region. Using two vibrating wires as a generator and a detector of vortices, the time-of-flight of vortices propagating a distance of 0.88 mm was measured at 1.25 K. We find that the time-of-flights distribute from 0.06 s to 27.4 s, much larger than the lifetimes of circular vortex rings limited in the size of a generator amplitude. These results imply that large vortex rings with non-circular shape or vortex tangles are created by the generator, propagating slowly and colliding with the detector before complete disappearance.
KeywordsQuantized vortex Quantum turbulence Oscillatory flow Superfluid helium
Unable to display preview. Download preview PDF.
- 1.L. Skrbek, W.F. Vinen, in Progress in Low Temperature Physics, vol. 16, ed. by W.P. Halperin, M. Tsubota (North-Holland, Amsterdam, 2008), p. 195 Google Scholar
- 15.R.J. Donnelly, Quantized Vortices in Helium II (Cambridge University Press, Cambridge, 1991) Google Scholar
- 19.S. Yamamoto, H. Adachi, M. Tsubota, Transition to quantum turbulence and the propagation of vortex loops at finite temperatures. J. Low Temp. Phys., in these proceedings Google Scholar