2005 年 30 巻 2 号 p. 16-22
Liquid hydrogen has properties of low temperature, low density, low viscosity, high compres-sibility, a high sensitivity of vapor pressure to temperature, etc.. The liquid hydrogen requires a high speed impeller because of its low density. Its low viscosity raises pump efficiency, on the othe hand , it often causes shaft vibrations of large amplitude due to small damping. To design and operate the liquid hydrogen pump, properties of liquid hydrogen shoud thoroughly be taken into consideration.