Role of cryogenic helium in classical fluid dynamics: Basic research and model testing

Abstract

Publisher Summary This chapter elaborates the basic research and model testing of the role of cryogenic helium in classical fluid dynamics. The physical properties of helium gaseous state near the critical point vary rather sensitively with pressure and one can attain a vast range of Reynolds and Rayleigh numbers in an apparatus of fixed size and design. The use of helium allows dynamic similarity to be attained simultaneously in more than one parameter such as in Reynolds and Froude numbers. The operation of a helium tunnel is no different in principle from that of a water tunnel, but the advantage of a helium I tunnel is the small size. The properties of liquid helium, especially helium II, vary rapidly with temperature. These variations can be used to advantage in modeling the motion of ships or waves on a free surface. Operating in helium gives greater flexibility for matching similarity parameters. The superfluid helium and the hypothesis of vortex-coupled superfluidity are also elaborated.