Abstracts
I3.1
Statistics of quantum turbulence
Victor S. L’vov and Anna Pomyalov
Dept. of Chemical Physics, Weizmann Institute of Science, Rehovot 17600, Israel
Based on the current understanding of statistics of quantum turbulence in
4
He and
3
He as well as on the results of its ongoing analytical, numerical and experimental
studies, we discuss the following problems in the large-scale, space-homogeneous,
steady-state turbulence: Energy spectra of the normal and superfluid velocity
components; Cross-correlation function of the normal and superfluid velocities;
Energy dissipation by mutual friction and viscosity; Energy exchange between
the normal and superfluid components; High-order statistics and intermittency
effects. The statistical properties will be discussed for different types of turbulent
flows: coflow of
4
He; flow of
3
He-B with laminar normal fluid; pure superflow
and counterflow of
4
He.
I3.2
Quantum turbulence in
4
He studied using the SHREK facility
Yury Mukharsky(5), C. Baudet(1,2), M. Bon Mardion(3,4), P. Bonnay(3,4), F.
Chill`a(6), L. Chevillard(6), F. Daviaud(5), P. Diribarne(3,4), B. Dubrulle(5), D.
Faranda(5), B. Gallet(5), M. Gibert (7,8), A. Girard(3,4), J.M. Poncet(3,4), J.-P.
Moro(9), P.-E. Roche(7,8), B. Rousset(3,4), E. Rusaou¨en(7,8), J. Salort(6), E-W.
Saw(5), S. Nazarenko(10), A. Golov(11)(SHREK collaboration)
SHREK collaboration
1. Univ. Grenoble Alpes, LEGI, Grenoble, France
2. CNRS, LEGI, Grenoble, France
3. Univ. Grenoble Alpes, INAC-SBT, Grenoble, France
4. CEA, INAC-SBT, Grenoble, France
5. SPEC, CEA-CNRS, Universite Paris-Saclay
6. Laboratoire de Physique de l’ ´ENS de Lyon, CNRS/Universit´e Lyon, Lyon,
France
7. Univ. Grenoble Alpes, Institut NEEL, Grenoble, France
8. CNRS, Institut NEEL, Grenoble, France
9. CEA, DEN-DANS-DM2S-STMF-LIEFT, Grenoble, France
10. Warwick Uniwersity, Inst. of Mathematics, UK
11. Manchester University, School of Physics and Astronomy, UK.
We will present recent results from SHREK collaboration. Different sensors were
used to characterize the turbulence: hot wire anemometer, Pitot tubes, flexible
cantilever anemometer and second-sound absorption. The Pitot tubes have new
design which allows for potentially wider frequency range. I will also present a
novel noise-reduction method of spectral averaging. The method allows to average
down to zero almost all sources of sensor and preamplifier noise, including thermal
noise.
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