A jet pump with adjustable area ratio

Abstract

The invention relates to a jet pump with an adjustable area ratio. The jet pump is characterized in that a nozzle of the jet pump is an adjustable nozzle, wherein the adjustable nozzle comprises a nozzle annular hinge mechanism and an annular locking device; the nozzle annular hinge mechanism comprises a curved blade, a rotating shaft sleeve, a sealing strip and a rotating shaft; the annular locking device comprises a locking bolt, a locking ring, an adjusting nut and an abutting piece; the locking ring sleeve of the annular locking device is arranged on the surface of the curved blade of the nozzle annular hinge mechanism in a sleeving manner; the annular locking device is used for adjusting the opening of the locking ring through the interaction of the locking bolt, the adjusting nut and the abutting piece; the locking bolt is provided with scales which represent the reading of the area ratio.

Description

technical field [0001] The invention relates to a jet pump with adjustable area ratio, in particular to a jet pump which can adjust the nozzle contraction angle of the jet pump through a locking device without disassembling the jet pump to adjust the cross-sectional area of ​​the nozzle. Background technique [0002] The jet pump uses liquid as the working medium, and through the turbulent diffusion of fluid particles, it transfers energy to a fluid mechanical device to be pumped; the jet pump is composed of a nozzle, a throat, a suction chamber and a diffusion tube; the throat and The nozzle area ratio is the most important size parameter of the jet pump, which directly affects the performance of the jet pump; when the ratio of the throat area of ​​a jet pump to the nozzle area is fixed, even if the other dimensions change within a certain range, the performance curve of the jet pump will be affected. Changes are very limited. [0003] However, it is difficult for the jet ...

AI Technical Summary

Problems solved by technology

[0003] However, it is difficult for the jet pump to work stably in the high-efficiency area when it is working. Changes in the head flow of the working hydraulic power source and the water level of the suction liquid will cause the jet pump to deviate from the original working point; and the jet pump is often designed according to the supporting power machine. , if used alone or with other power machines, it is difficult for the jet pump to operate in the design working area, which not only greatly reduces the efficiency of the jet pump, but also is more prone to cavitation; therefore, the use of a jet pump with a fixed area ratio has a great advantage Limitation, in order to meet the needs of different workplaces, replacing a new jet pump is not only time-consuming and laborious, but also will greatly increase the cost

[0004] Therefore, it is of great practical significance to develop a jet pump with an adjustable area ratio. At present, most of the existing adjustable jet pumps are adjustable annular jet pumps (201310141547.9), which consist of rectifying components, mixing tubes, throats, diffusers, The outlet pipes are connected sequentially, and the rectifier pipe is connected with the working fluid pipe. One end of the rectifier pipe is provided with an end cap, and the suctioned fluid pipe passes through the end cap and moves axially relative to the end cap. The area ratio is adjustable, and the performance can be adjusted according to the working conditions. Adjustment, however, the jet loss of annular jet is larger than that of center jet pump, and its structure is suitable for the transportation of solid particles such as minerals, live fish, capsules, potatoes and onions; while the existing adjustable center jet pumps (90109386.6, 201020526369.3) are all It is achieved by replacing the nozzle. The nozzle is threaded through the boss on the main body of the jet pump and the main body of the jet pump, and the nozzle is replaced through the threaded connection, thereby achieving the purpose of adjusting the area ratio; not only additional nozzles are required to provide a variety of required areas ratio, and the pump must be stopped and replaced every time, which is time-consuming and laborious; irrigation and drainage machinery "Numerical Simulation of Adjustable Jet Pump Performance" (No. 6, 2008) proposed a thimble type variable area ratio jet pump, and its working principle is Adjusting the thimble installed behind the nozzle and concentric with the nozzle changes the flow area of ​​the nozzle to adjust the area of ​​the jet pump; however, because the thimble occupies the center flow channel of the jet pump, the working fluid flow channel forms a ring and destroys the jet flow. The flow field in the core area not only causes resistance loss, but also makes the jet flow field turbulent, which affects the normal operation of the jet pump

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