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Title: Is inertial-range intermittency of superfluid turbulence the same as classical?
Plain: Above about one kelvin, superfluid helium is a mixture of a superfluid and a normal fluid, and its turbulence shows the same average spectrum as water. Whether its rare violent fluctuations are also the same at every temperature is disputed.
Precise: In quasiclassical turbulence of 4He between about 1.2 K and $T_{\lambda}=2.17\,\mathrm{K}$, are the inertial-range velocity structure-function exponents $\zeta_p$ equal to the classical values for all superfluid fractions $\rho_s/\rho$, or does intermittency change where $\rho_s/\rho$ is small or close to 1? Answer: $\zeta_p(T)$ for p up to 6 with error bars.
Settled by: Probe measurements with characterized response resolving inertial-range increments at several temperatures in one flow, compared with two-fluid simulations.
Kind: well-posed
Answer type: yes-no
References: (empty)
Literature status: contested
Status note: Simulations since about 2013 report temperature-dependent intermittency, while probe experiments (about 2017) find none; the disagreement is unresolved.
Posed since: (empty)