24 citations · 61 across the 7 of their papers we have counts for
7 papers
On the Transition from Potential Flow to Turbulence Around a Microsphere Oscillating in Superfluid ^4He
Michael Niemetz, Risto Hänninen, Wilfried Schoepe
The flow of superfluid He around a translationally oscillating sphere, levitating without mechanical support, can either be laminar or turbulent, depending on the velocity ampl…
Kelvin waves from vortex reconnection in superfluid helium at low temperatures
R. Hänninen
We report on the analysis of the root mean square curvature as a function of the numerical resolution for a single reconnection of two quantized vortex rings in superfluid helium.…
Comment on "Reconnection of quantized vortex filaments and the Kolmogorov spectrum"
R. Hänninen
In this Comment we would like to emphasize that in Phys. Rev. B 90, 104506 (2014) the calculated energy spectrum takes into account only the small interaction (cross) term and, add…
Dissipation enhancement from a single vortex reconnection in superfluid helium
R. Hänninen
We investigate a single vortex reconnection event in superfluid helium at finite temperatures using the vortex filament model. The reconnection induces Kelvin waves which strongly…
Steady-state spectrum of Kelvin waves on a quantized vortex at finite temperatures
R. Hänninen
We determine numerically the steady-state spectrum for Kelvin waves on a superfluid 4He vortex that is driven by shaking its end points and damped by mutual friction. The relaxatio…
Frequency Dependence of the Critical Velocity of a Sphere Oscillating in Superfluid Helium-4
R. Hänninen, W. Schoepe
It is shown that the critical velocity of a small sphere oscillating in superfluid helium increases with the square root of the oscillation frequency. This behavior can be describe…
Model of Inhomogeneous Impurity Distribution in Fermi Superfluids
R. Hänninen, E. V. Thuneberg
The standard treatment of impurities in metals assumes a homogeneous distribution of impurities. In this paper we study distributions that are inhomogeneous. We discuss in detail t…