1997 年 22 巻 1 号 p. 39-45
There are two methods to improve the volumetric efficiency of a high pressure liquid hydrogen pump operating in liquid hydrogen. One is to improve the suction efficiency and the other is to decrease the leakage through the clearance between the piston and the cylinder of the pump. A suction booster was applied to the high pressure liquid hydrogen pump to obtain much greater suction efficiency. And a piston ring sealing was also applied to obtain much smaller leakage. It has been found in our experimental study that the two methods have contributed to the increase of the volumetric efficiency to a large extent.