Heat transfer and flow of He II in narrow channels

✍ Scribed by T. Suekane; M. Sekiguchi; S. Hirai; T. Okamura

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 263 KB
• Volume: 43
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/s0011-2275(03)00050-x

✦ Synopsis

Heat transfer and fluid flow of He II in a long, narrow channel connected to a bath that supplies a constant supply of heat have been investigated by numerical simulations by using the simplified model of Kitamura et al. [Cryogenics 37 (1) (1997) 1]. Such channels are used to cool compact, stable, low-temperature magnets. The fluid flow is driven by natural convection and the mutual friction between the normal fluid and the superfluid.

In this model, the thermomechanical effect and the Goter-Mellink mutual friction balance each other. A consequence of this balance is that the velocity and temperature distributions of He II can be characterized by a dimensionless, dependent parameter equal to the ratio of the fluid speeds of internal convection to the total fluid flow. After a sudden application of heat flux, the internal convection dominates over the total fluid flow until the establishment of steady-state temperature gradients. This predicts that the time required to set up the steady-state total fluid flow is proportional to the total heat capacity in the channel.