Mechanical pumps for superfluid helium transfer in space

✍ Scribed by M.G. Izenson; W.L. Swift

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 509 KB
• Volume: 28
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(88)90052-5

✦ Synopsis

Two alternate mechamcal pump concepts have been =dent)fled for the transfer of superflu~d hehum m space Both pumps prov)de flow at sufficient head and have operating charactenstics suitable for the Space Infrared Telescope Famhty (SlRTF) refill mission One pump operates at a relat)vely low speed and utd=zes mechamcal roller bearings, while the other operates at a h)gher rotational speed using either electromagnetic or tdtmg pad gas-dynamic bearings The use of gas bearings requires transfer of normal hehum so that the gas pressure w=thm the pump casing =s h=gh enough to operate the bearings The operating charactenst=cs of both pumps are pred)cted, the dlmenmons are estimated and major technology Issues are =dentff=ed The major msues for each pump design are cawtat)on performance and bearing development Roller beanngs reqmre quantff)ed rehabd)ty for operatmn in space wh)le electromagnet=c bearings requ)re basic development as well as a complex control system The low speed pump has s=gmficantly poorer hydrauhc effic=ency than the h=gh speed pump

Keywords helium, helium pumps, bearings, space eryogen,cs

Two alternate centrifugal pumps have been identified to satisfy the transfer requirements for hehum replenishment of the Space Infrared Telescope Facihty (SIRTF) The pump designs differ in rotational speed, impeller geometry, hydraulic efficiency and bearing types This Paper discusses how the requirements for the transfer of helium in space affect pump design The two alternate pumps are described and the major design trade-offs discussed Both pumps require technology development in the areas of He II cawtation and in journal bearing design or reliablhty *Paper presented at the Space Cryogemcs Workshop, Madison,