TABLE OF CONTENTS RICHARD G. CUNNINGHAM
The jet pump transfers energy from a liquid or gas primary fluid to a secondary fluid. The latter may be a liquid, a gas, a two-phase gas-in-liquid mixture, or solid particles transported in a gas or a liquid. Examples of all these combinations have been reported in the technical literature. Reference 1, the major bibliography in this field, contains over 400 abstracts. Although the terms "ejector" and "ejector" are also applied, the term "jet pump" will be used here. The jet pump offers significant advantages over mechanical pumps: no moving parts for improved reliability, adaptability to installation in remote or hazardous environments, simplicity, and low cost. The primary drawback is efficiency: both frictional losses and unavoidable mixing losses are incurred. Nevertheless, careful design can produce pumps with efficiencies on the order of 30-40%. The jet pump in Figure 1 is typical of liquid-jet pumps and low Mach-number gas-jet/gas pumps. Compressible-flow pumps, for example, steam-jet ejectors, employ converging-diverging nozzles for full expansion of the jet.
| A | = | area, ft 2 (m 2) |
| A w | = | throat wall area, ft 2 (m 2) |
| C | = | velocity of sound, ft/sec (m/s) |
| CR | = | cavitation resistance |
| D | = | diameter, ft (m) |
| E | = | energy rate, ft lb/sec (joule/s) |
| K | = | friction loss coefficient |
| K | = | absolute temperature, Kelvin |
| LJL | = | liquid-jet liquid pump |
| LJG | = | liquid-jet gas compressor |
| LJGL | = | liquid-jet... |
