Performance in He II of a centrifugal pump with a jet pump inducer
Abstract
The tendency of turbopumps operating in He II to cavitate makes their use in zero gravity questionable because of the zero net positive suction head ( NPSH) available at the pump inlet. We investigated a jet pump, positioned at the inlet of a centrifugal pump with a screw inducer, as a means of operating a centrifugal pump at zero or lower NPSH. Pump performance in He II was measured as a function of NPSH for six different combinations of primary and secondary nozzles. Suction heads down to -91 mm were measured for a 3% reduction in developed head. These are referenced to the leading edge of the screw inducer, which is 100 mm above the jet pump inlet. Because cavitation at the primary jet always precedes cavitation in the jet pump secondary nozzle, we also tested reverse (pressure driven) flow through a porous plug as a means of obtaining a subcooled primary jet. These brief tests were inconclusive.
- Publication:
-
Cryogenics
- Pub Date:
- May 1989
- DOI:
- 10.1016/0011-2275(89)90108-2
- Bibcode:
- 1989Cryo...29..563D
- Keywords:
-
- Cavitation Flow;
- Centrifugal Pumps;
- Jet Pumps;
- Liquid Helium 2;
- Performance Tests;
- Weightlessness;
- Infrared Telescopes;
- Mission Planning;
- Nasa Space Programs;
- Superfluidity;
- Engineering (General)