Performance of an Inducer-Impeller Combination at or near Boiling Conditions for Liquid Hydrogen

Abstract

As early as 1945, there was evidence that, in addition to the flow parameters normally considered to affect the cavitation performance of a pump, there existed a further influence derived from the thermodynamic properties of the fluid being pumped[¹]. In the case of hot water, Stahl and Stepanoff[²] have shown a difference in performance from cold-water results with all other cavitation parameters being equal Similarly, Salemann[³] demonstrated a difference and effected a correlation between butane and water test results. In cryogenic liquids, Carter[⁴] has reported a small but definite effect for liquid oxygen and Caine et al.[⁵] have discussed thermodynamic effects in liquid hydrogen. Previously in an early report on pumping liquid hydrogen, Jacobs et al.[⁶] derived a “Cavitation Tendency” parameter based on thermodynamic properties, which predicted improved cavitation performance in liquid hydrogen.