arXiv subjects

K. L. Henderson

Publications and source records attributed to K. L. Henderson.

2 recordsLinked to original sources

arXiv2004

Vortex waves and the onset of turbulence in $^3$He-B

In a recent experiment Finne et al. discovered an intrinsic condition for the onset of quantum turbulence in $^3$He-B, that q=alpha/(1-alpha')<1, where alpha and alpha' are mutual friction parameters. The authors argued that this condition corresponds to Kelvin waves which are marginally damped, so for q>1 Kelvin waves cannot grow in amplitude and trigger vortex reconnections and turbulence. By analysing both axisymmetric and non-axisymmetric modes of oscillations of a rotating superfluid, we confirm that in the long axial wavelength limit the simple condition q=1 is indeed the crossover between damped and propagating Kelvin waves.

cond-mat↗

arXiv2003

Transition from Ekman flow to Taylor vortex flow in superfluid helium

By numerically computing the steady axisymmetric flow of helium II confined inside a finite aspect ratio Couette annulus, we determine the transition from Ekman flow to Taylor vortex flow as a function of temperature and aspect ratio.We find that the low-Reynolds number flow is quite different to that of a classical fluid, particularly at lower temperatures.At high aspect ratio our results confirm the existing linear stability theory of the onset of Taylor vortices, which assumes infinitely long cylinders.

cond-mat↗