Abstract
The types of the oscillations of very low temperature circulation systems are reviewed.
Despite the considerable success of the techniques which were developed in '60s to analyse the dynamical and transient behaviors of cryogenic systems, the incompetence thereof to predict exactly the modes of oscilllations and instabilities of the He systems operated around the critical point now becomes gradually apparent. The chief aim of this review is to clarify where they fail and suggest how we can save them.
The evidences which show the abnormally swift diffusion of enthalpy along supercritical He channels are presented. The relationship between oscillation modes and inhomogenuities of temperature, density and velocity of He coolant is stressed.
