Inter-vortex spacing in superfluid turbulence: temperature and Reynolds number dependences

Philippe-Emmanuel Roche (1) , Simone Babuin (2) , Emmanuel Lévêque (3) , Emil Varga (4)

1 NEEL - HELFA - Hélium : du fondamental aux applications
2 Institute of Physics
3 LMFA - Laboratoire de Mecanique des Fluides et d'Acoustique
4 UK - Univerzita Karlova [Praha, Česká republika] = Charles University [Prague, Czech Republic]

The typical spacing between superfluid vortices in an isothermal turbulent tangle is proportional to the integral scale H rescaled by the quantum Reynolds number Reκ = H · V · κ −1 to the power of 3/4, where κ is the quantum of circulation around of single vortex [1]. This empirical relation can be seen as the quantum-turbulence version of the corresponding well-know equation giving Kolmogorov dissipative scale in classical turbulence. In 2014, we studied the temperature dependence of the numerical factor δ/H × Re 3/4 κ in 4 He by joint numerical and experimental analysis of steady state turbulence over a wide temperature interval (1.2-2.16 K) [2]. Agreement between the two analyses was found good except at the very ends of this temperature interval. We will discuss this issue by presenting additional experimental data obtained by post-processing of superfluid experiments published between 1975 and 1998 [3, 4, 5].

Domaines: Autre [cond-mat.other]

Philippe-Emmanuel Roche, Simone Babuin, Emmanuel Lévêque, Emil Varga. Inter-vortex spacing in superfluid turbulence: temperature and Reynolds number dependences. 15th EuropeanTurbulence Conference, Aug 2015, Delft, Netherlands. ⟨hal-01528319⟩