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تسجيل مستخدم جديدVelocity Distributions of Tracer Particles in Thermal Counterflow in Superfluid $^4$He
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Quantum turbulence accompanying thermal counterflow in superfluid $^4$He was recently visualized by the Maryland group, using micron-sized tracer particles of solid hydrogen (J. Phys. Soc. Jpn. {bf 77}, 111007 (2008)) . In order to understand the observations we formulate the coupled dynamics of fine particles and quantized vortices, in the presence of a relative motion of the normal and superfluid components. Numerical simulations based on this formulation are shown to agree reasonably well with experimental observations of the velocity distributions of the tracer particles in thermal counterflow.
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We report on a combined theoretical and numerical study of counterflow turbulence in superfluid $^{4}$He in a wide range of parameters. The energy spectra of the velocity fluctuations of both the normal-fluid and superfluid components are strongly an
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In the thermally driven superfluid He-4 turbulence, the counterflow velocity $U_{rm ns}$ partially decouples the normal and superfluid turbulent velocities. Recently we suggested [J. Low Temp. Phys. 187, 497 (2017)] that this decoupling should tremen
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