Characteristics of long distance superfluid helium heat transport

Long distance heat transport system with superfluid helium (He II) is required for future superconducting accelerator systems. Heat transport characteristics of pressurized He II (He IIp) system and saturated He II (He IIs) system have been investigated by numerical analysis. The tested model consists of two separated baths. The distance between the baths is fixed to 1 km. The baths are connected by a He II channel for the case of the He IIp system, while for the case of the He IIs system, the baths are connected by two channels, the upper one being for vapor flow and the lower one containing He II. Dominant factors which affect the cooling ability of the He IIp and He IIs systems are thermal resistance in the He II channel and pressure drop in the vapor flow channel, respectively. The heat generated in the He II bath can be removed by a relatively thinner channel with the He IIs system by using the latent heat of liquid. (author)