Jet pumps: device, application, operating principle

Pumping various liquids and substances the equipment is presented in the market in different versions. Developers seek to optimize the design in order to ensure high performance and adequate power. However, with increasing efficiency, the reverse process of rapid wear of working elements during operation is observed. In turn, jet pumps are spared from such drawbacks, since they do not have working components that would be subjected to intensive loads. To understand the other features and advantages of the units of this type, you should consider their construction in more detail.

Pump unit

The device does not provide for the presence of rotating elements, and structural parts and components are oriented to ensure the operation of functional fluids. The pump consists of four components, including a suction chamber, a nozzle, a mixing tank and a diffuser. Also, the device of the jet pump can provide a complete set with special nozzles intended for supply of working fluids. One model of the unit can be supplemented with different characteristics of the narrowing elements. The design is presented in different modifications and depending on the type of hydraulic carrier used. In particular, there are devices for working with liquid media, gaseous substances and hydrosmic mixtures.

How do inkjet pumps work?

Such devices operate on the basis of the kinetic energy transfer principle. The power charge is transmitted from the streams of functional fluids to the pumped medium. It is important to note that during the transfer process, mechanical devices and intermediate nodes are not involved. High power feedback is provided by the speed at which the working fluid is discharged from the nozzle under pressure. In the absence of moving components, the role of the vacuum chambers with which the jet pump is equipped increases. The principle of operation of the unit provides for the formation of free space in the reservoir, where the liquid is sucked in. That is, the carrier from the receiving chamber through the suction channels is sent to the reservoir, and then to the mixing compartment. In the process of the fusion of a functional fluid and a carrier, energy is exchanged, as a result of which the flow strength is weakened. The final point in the simplest systems is the collection capacity, into which the medium comes at a reduced speed, but with a saved head.

Performance Characteristics

Typically, such units, in which sparing, from the point of view of wear and tear of the structure, liquids are implemented, do not differ in high operational parameters. Part of the example of jet pumps confirms this, but in some application segments its capabilities are quite sufficient. For example, the performance of devices can reach 30 l / c. This indicator refers to professional equipment, and simplified designs provide an average of 15-17 l / c. With regard to the lifting height, the operation of the jet pump is calculated on a range of 8-15 m, although some modifications for specialized purposes can provide a 20-meter lift. But in this case, significantly reduced productivity and efficiency, so for such needs are often used alternative designs of pumps.

Types of pumps

As noted above, the designs differ in the type of liquid served. Now it is worthwhile to consider them in more detail. The most popular models work with water carriers and mixtures that do not have a destructive effect on the communication infrastructure of the unit. Such devices are called ejectors and operate on the principle of evacuation and suction in different chambers. Distributed and jet pumps, whose function is focused on servicing aggressive environments. These are airlifts used in wells and communication systems that ensure the transfer of chemically active mixtures and liquids with the presence of solid particles. Less popular, but in some cases, injectors are irreplaceable. These are devices that also work with liquids, but the functional medium in this case is steam.

Applications

A variety of design options determined the appropriate distribution of pumps of this type. In particular, they are used in the chemical industry for pumping acids, alkalis, oily carriers, salt mixtures and fuel oil. Technologists in this industry appreciate the mechanical endurance and durability, which distinguishes a jet pump. The use of such units in the domestic sphere is mainly oriented to raising water from wells. Some modifications are quite suitable for the formation of artesian sources. Also, high temperature resistance characteristics allow such equipment to be used in heating systems. For sewers, this solution is also beneficial, since the pump effectively copes with the removal of sediments in the form of silt and sand.

Advantages and disadvantages of jet aggregates

Among the main advantages of such units are a simple and reliable design, durability in operation, reliability and lack of sensitivity to aggressive environments. To a large extent, these advantages are due to the fact that jet pumps are spared from the presence of moving parts, which in other pumps quickly wear out. By the way, this same design feature allows to carry out pumps in small sizes, which also affects the minimization of maintenance costs. But there are drawbacks in such devices, among which there is a need for special preparation of working fluids and low performance indicators.

Conclusion

The principle of operation of jet aggregates determined their specific direction of operation. Such equipment is practically not used in traditional water supply and irrigation systems. But, due to the high wear resistance index, jet pumps have found their place in communication systems operating under conditions of high loads. Suffice it to say that the units effectively cope with the maintenance of chemicals and contaminated media, while maintaining the original performance. But to pay for such a weighty advantage to equipment owners have a modest power potential. Low productivity is not always the decisive factor in the selection of pumps, so the demand for jet devices remains.