Ingeniero De Petroleos

ANA
ANA-VERFAHRENSTECHNIK GmbH • Postfach 1153 • D-06201 Merseburg

ANA-VERFAHRENSTECHNIK GmbH

Design and principle of operation of jet pumps
Jet pumps are used in nearly every branch ofindustry for conveying, mixing and compression of liquids or gases. Jet pumps have no movable parts, need no mechanical drive and are designed in a simple structure.

spin element in the driving nozzle.The resulting rotation of the liquid causes a better mixing between liquid and gas.
Jet pumps with gas or water vapour as driving medium have a “Laval” nozzle. This nozzle has first a decreasing,than an increasing cross section and accelerates the medium to supersonic speed.

The driving (motive) medium is expanded through a nozzle and generates a conveying effect. The change from pressureenergy to kinetic energy is combined with a decline of the static pressure, which has its lowest value directly after the nozzle. The suction medium inlet is in this part of the jet pump. The suctionstream is now mixed with the driving flow and the velocity increases. After mixing, the velocity of the mixing stream is reduced consequently. The pressure increases to the value of the counter pressure.A driving medium can be a gas or a fluid. The suction medium can also be a medium with impurities. The main parts of a jet pump, are the driving nozzle, mixing nozzle and diffusor. They are describedin the following passage: Driving nozzle:The driving nozzle is a flow canal with a circular cross section, designed in dependence on the kind of driving medium. If the driving medium is a liquid, thecross section decreases constantly in flow direction. Liquid jet pumps for conveying air or non condensable gas have an additional

Driving nozzles for steam jet heaters are designed in a way thatthe water travels through a very long and narrow cross section of the nozzle. The steam passes through lateral arranged bores and directly condenses in the water stream. Mixing nozzle:The mixing...