Hydrodynamics and heat transfer in a superfluid helium at high heat fluxes

The ability of helium to preserve a liquid state down to absolute zero makes it possible to use it in cryostats in the temperature range below 2.172 K. The unique properties of He-II - its superfluidity and high effective thermal conductivity - offer certain advantages for systems involving He-II-cryostats over other versions of cooling systems. In the years to come it is anticipated that the range of practical applications of He-II will expand. At present, investigations of heat transfer in He-II are carried out along the following three lines: steady-state heat transfer in large volumes in the region of high heat loads; heat transfer in He-II under conditions of internal convection and forced flow in channels; and unsteady-state heat transfer and non-linear acoustics. The aim of the paper is to survey recent achievements of Soviet scientists in this field