CN212006287U - Self-excited microfluidic controlled multi-tube oscillator - Google Patents

Abstract

The utility model belongs to the technical field of pressure gas's efflux control engineering refrigeration, a relate to self-excitation microjet control multitube oscillator, be the gas jet control if the essential special type of refrigerating machine equips. The utility model discloses a from main efflux separation with main efflux total pressure equal with the gas source fluid from the outside introduction self-excitation oscillation chamber, carry out the self-excitation oscillation and produce periodic microjet to from perpendicular excitation mouth attaching the wall side and pushing away and pressing main efflux, make main efflux oscillation with the mode of pushing and pulling main efflux, thereby improve and last total pressure, finally reach continuous oscillation in succession, solved self-excitation efflux oscillation and caused the high problem of energy consumption. The utility model has the characteristics of simple structure, operation maintenance convenience etc, and need not external power, the operation is reliable and stable, is a self-excitation microjet control multitube oscillator who is suitable for handling high-pressure gas medium.

Description

Self-excited microfluidic controlled multi-tube oscillator

technical field

The utility model belongs to the technical field of compressed gas jet flow control engineering refrigeration, relates to a self-excited micro jet flow control multi-tube oscillator, and is a special equipment necessary for gas jet flow control such as refrigeration machinery.

Background technique

Jet is a special type of fluid motion. It is related to the problem of jet flow in the fields of aviation industry, hydraulic engineering, medical and health, and automatic control. Therefore, jet has become an important content of fluid mechanics research. The jet oscillator is based on the theory of jet flow. On the basis of the jet oscillation element, an additional feedback channel generates fluid oscillation, and the flow measurement is realized by measuring the oscillation frequency of the fluid. The theoretical analysis of the nature and characteristics of the jet is the prerequisite for the study of the jet oscillator, which lays the foundation for the study of the micro-channel jet oscillator.

The working medium of the fluidic element is fluid, which can be divided into different categories. According to the different flow mechanism of the fluid inside the element, it can be divided into three categories: turbulent flow, Coanda type and momentum exchange type. The so-called Coanda jet element refers to a jet element made by the main jet in a chamber of a specific shape, using the Coanda effect generated by the unbalance of fluid entrainment.

Compared with the moving equipment jet control device actuator, the static wall-mounted jet controller has the advantages of good reliability, small size, high power and low cost, and can adapt to harsh radiation, strong corrosion, strong vibration and strong impact. working environment, and there is no loss of interference. Therefore, in complex working conditions such as high radiation, strong magnetic field, flammable and explosive, or in pure fluid working systems, jet controllers are widely used, such as certain control systems in the nuclear industry, aerospace and other fields. At the same time, the Coanda jet has switchable characteristics, which can realize flow control and fluid measurement. Therefore, the jet controller is also applied to the hydraulic excitation of oil production and the jet flow meter. Bistable Coanda jet element is an important direction of its development.

The gas distribution unit in the static gas wave refrigerator, the Coanda oscillator, is used to generate the oscillating pulse jet, which is the embodiment of the Coanda bistable jet element in practical application. In the past, Coanda oscillators used the excitation method of splitting the main jet and returning it to the main jet, so that the main jet continuously switched the Coanda to form oscillation, which is called self-excited Coanda oscillator. According to the different feedback circuits, it can be divided into feedback type, sonic type, resonance type and load type. Self-excitation is easy to implement, but the disadvantage is that the energy loss of oscillation is mostly as high as one-third.

The self-excited Coanda oscillator acts as a gas distribution unit in a static gas wave machine, providing periodic oscillating jets for subsequent refrigeration. So far, there have been many studies on the three types of Coanda oscillators: feedback type, sonic type and resonance type. The sonic Coanda oscillator is introduced into a static gas wave refrigerator. The sonic Coanda oscillator opens both sides of the oscillator cavity and communicates with the sonic tube, and transmits the pressure change signal generated when the jet Coanda is switched to the other side. , the jet is switched back and forth, and the Coanda oscillation occurs. The sonic oscillation type jet wall-coated oscillation refrigerator has superior working performance than before. The geometric parameters of the sonic Coanda oscillator are studied in detail. However, the focus of its research tends to be the influence of geometric size on the vibrability of the oscillator, the analysis of the flow characteristics of the internal flow field of the oscillator and the influence of the oscillation frequency, and there are relatively few discussions on the energy efficiency. The total pressure retention rate K that defines the energy efficiency characteristics of the Coanda oscillator and the jet deflection characteristics Degradation and premature fading due to flow loss are the main causes of energy loss. However, only relying on the main jet shunt feedback excitation, no matter how it is realized, cannot meet the two conditions of increasing the total pressure of the excitation flow and providing a continuous excitation driving force.

Utility model content

In order to solve the problem of high energy consumption caused by the above self-excitation, the utility model provides a self-excitation with no moving elements, simple structure, convenient operation and maintenance, no need for external power (energy), stable and reliable operation, and suitable for processing high-pressure gas medium. Microfluidic controlled multi-tube oscillator.

The utility model adopts the same gas source fluid, which is separated from the main jet and equal to the total pressure of the main jet, and is introduced into a self-excited oscillation cavity from the outside, performs self-excited oscillation to generate periodic micro-jets, and pushes the main jet from the vertical excitation port on the side of the attached wall , the main jet is oscillated by means of push-pull main jet, thereby increasing and sustaining the total pressure. The self-excited oscillating cavity uses a sonic oscillating jet generator as the micro-jet jet controller of the present utility model, so that the main jet is distributed.

The principle of the oscillating jet generator is based on the bistable effect of the jet Coanda and the switching characteristics of the jet steady state disturbance. Since it is impossible for a static refrigerator to provide a periodic disturbance source from the outside, it must, like an electronic oscillation circuit, require self-excited conditions to generate self-excited oscillations. In the oscillator structure of the sonic wall-mounted oscillator, the control ports on both sides of the oscillating cavity are directly connected to form a closed pipeline, which is called a sonic tube (control tube). The control tube is an important part of the self-excited Coanda oscillator, and the difference of its structure and position determines the type and excitation principle of the self-excited oscillator. In the sonic Coanda oscillator, fluid entrainment occurs at the nozzle of the sonic tube, and a pressure difference is formed at the openings on both sides of the nozzle of the sonic tube. Under the action of the pressure difference, the jet periodically switches the Coanda to form an oscillating jet.

The total pressure loss of self-excited Coanda oscillators (positive feedback type, sonic type and resonance type) is large, and the total pressure of self-excited flow is reduced and prematurely decayed due to the loss of the flow channel, which is the main reason for the energy loss.

In the oscillating jet generator of the present utility model, the method corresponding to the problem of energy loss is to separate a small part of the same gas source fluid from the main jet, which is equal to the total pressure of the main jet, and introduce it into the self-excited oscillating cavity from the outside to carry out the self-excited oscillating jet. The oscillating microjet becomes the excitation source of the main jet, and the switching control of the main jet is carried out.

The technical scheme adopted by the utility model to solve its technical problems is:

The self-excited micro-fluidic controlled multi-tube oscillator mainly includes an oscillating body 18 and a cold air recovery device 21;

The oscillating body 18 includes a bottom plate, an upper cover 12, a micro-jet inlet pipe 13, an elbow 14, a tee 15, a main jet inlet pipe 16, an inlet pipe 17, a pipe fixer 24 and a receiving pipe 11; the upper surface of the bottom plate There are different cavities and flow channels, which are connected to each other to form the flow channel 19 of the oscillating body 18. The flow channel 19 is a left-right symmetrical structure, including the micro-jet flow into the oral cavity 1, the micro-jet nozzle flow channel 2, the sound wave control tube 3, and the split. Bifurcated flow channel 4, main jet inlet 5, main jet nozzle flow channel 6, jet control port 7, oscillation cavity 8, multi-tube bifurcated flow channel 9, exhaust port 10 and exhaust channel 20; the sonic control tube 3 is located in the The front end of the oscillating body 18 is surrounded by a square annular flow channel. The micro-jet flow into the oral cavity 1 and the micro-jet nozzle flow channel 2 are located in the square ring surrounded by the sonic control tube 3. One end of the micro-jet nozzle flow channel 2 is connected with the micro-jet flow into the oral cavity. 1 is connected, and the other end is connected with the middle position of one side of the sound wave control tube 3; the bifurcated flow channel 4 is a left-right symmetrical structure, enclosing a water drop-shaped annular flow channel, and the left and right parts respectively include a straight section and a curved section, and the straight section and the curved section The sections are connected end to end, and the outer ends of the two straight sections meet at the middle of one side of the sonic control tube 3, so that the bifurcated flow channel 4 is connected to the micro-jet inflow mouth 1 and the micro-jet nozzle flow channel 2. The outer end meets the jet control port 7; the main jet flow into the mouth 5 and the main jet nozzle flow channel 6 are located in the droplet-shaped ring surrounded by the bifurcated flow channel 4, and one end of the main jet nozzle flow channel 6 is communicated with the main jet flow into the oral cavity 5, The other end is communicated with the jet flow control port 7; the oscillating cavity 8 and the multi-tube bifurcated flow channel 9 are located at the rear end of the oscillating body 18, one end of the oscillating cavity 8 is communicated with the jet flow control port 7, and the other end is connected with the multi-tube bifurcated flow channel 9 The front end is connected; the tail of the oscillating body 18 is provided with a plurality of exhaust ports 10, and the exhaust ports 10 are respectively connected with each branch at the rear end of the multi-pipe branched flow channel 9; the receiving pipe 11 is installed from the outside of the tail of the oscillating body 18 On the exhaust port 10, and fixed by the pipe fixer 24;

The upper cover 12 is covered on the bottom plate, and the upper cover 12 is provided with two through holes, which correspond to the micro-jet inlet 1 and the main jet inlet 5 respectively, and the micro-jet inlet pipe 13 and the main jet are respectively installed on the through holes. The inlet pipe 16, the micro-jet inlet pipe 13 is communicated with the micro-jet inlet port 1, the main jet inlet pipe 16 is communicated with the main jet inlet port 5; the inlet pipe 17 is installed on the outside of the upper cover 12, and is The inlet pipe 17 communicates with the microjet inlet pipe 13 and the main jet inlet pipe 16;

The tail of the bottom plate is provided with a plurality of inclined exhaust channels 20 penetrating the bottom of the bottom plate, and the exhaust channels 20 correspond to the exhaust ports 10 and communicate with each other;

The cold air reclaimer 21 is installed at the bottom of the tail end of the oscillating body 18, and includes a cold air outlet 23 and a cold air outlet 22. The cold air outlet 23 is communicated with the cold air outlet 22; the plurality of exhaust channels 20 are all communicated with the cold air outlet 23. The cool air is discharged from the cool air outlet 22 .

The bottom plate, the upper cover 12 and the cold air recovery device 21 are fixed by bolts 25 .

The inclination angle of the exhaust passage 20 is 45°, and the angle between the branches of the multi-pipe branch flow passage 9 is 10°˜50°.

The material of the oscillating body 18 is acrylic plate or metal, which is processed by laser cutting, and slowly transitions to a circular section at the position of the rectangular section of the oscillating jet outlet.

The length of the extension section at the end of the receiving pipe 11 can be determined according to actual needs, and is connected to the outside with a pipe joint.

The beneficial effect of the utility model is that the main jet is controlled by the micro-jet without any moving parts being sealed, and the utility model has the advantages of good reliability, small volume, high power, low cost, and is suitable for the oscillator of the expansion refrigerator for processing high-pressure gas medium. And can adapt to harsh working environment such as strong radiation, strong corrosion, strong vibration and strong impact, and there is no electronic interference. Therefore, it can be widely used in complex working conditions such as high radiation, strong magnetic field, flammable and explosive, or in pure fluid working systems, such as some control systems in the nuclear industry, aerospace and other fields. At the same time, the Coanda jet has switchable characteristics, which can realize flow control.

Description of drawings

FIG. 1 is a schematic diagram of the device of the self-excited micro-fluidic control multi-tube oscillator of the present invention.

FIG. 2 is a top view of the self-excited micro-fluidic control multi-tube oscillator of the present invention.

FIG. 3 is a front view of the self-excited micro-fluidic control multi-tube oscillator of the present invention.

FIG. 4 is a side view of the self-excited micro-fluidic controlled multi-tube oscillator of the present invention.

In the picture: 1 jet into the oral cavity, 2 micro-jet nozzle flow channels, 3 sonic control tubes, 4 bifurcated flow channels, 5 main jet flow into the oral cavity, 6 main jet nozzle flow channels, 7 jet control ports, 8 oscillation chambers, 9 more Tube bifurcation flow channel, 10 exhaust port, 11 receiving tube, 12 upper cover, 13 micro-jet inlet tube, 14 elbow, 15 tee, 16 main jet inlet tube, 17 inlet tube, 18 oscillator body, 19 flow channel , 20 exhaust passages, 21 air recovery, 22 cold air outlet, 23 air outlet, 24 pipe fixer, 25 bolts.

Detailed ways

The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions.

A typical embodiment of the present invention is as follows:

The same gas source fluid separated from the main jet and equal to the total pressure of the main jet is introduced into the self-excited oscillation cavity from the outside, and the self-excited oscillation is carried out to generate periodic micro-jets, and the main jet is pushed from the vertical excitation port on the side of the wall. The way of pulling the main jet makes the main jet oscillate, thereby increasing and sustaining the total pressure. The self-excited oscillating cavity uses a sonic oscillating jet generator as the micro-jet jet controller of the present utility model, so that the main jet is distributed. The change of the length of the sonic control tube can change the switching frequency of the micro-jet Coanda.

As shown in FIG. 3 , the self-excited micro-fluidic controlled multi-tube oscillator of the present invention mainly includes an oscillating body 18 and a cold air recovery device 21 .

As shown in FIG. 2, the oscillating body 18 includes a bottom plate, an upper cover 12, a micro-jet inlet pipe 13, an elbow 14, a tee 15, a main jet inlet pipe 16, an inlet pipe 17, a pipe holder 24 and a receiving pipe 11; The upper surface of the bottom plate is provided with different cavities and flow channels, which are connected to each other to form the flow channel 19 of the oscillating body 18. The flow channel 19 is a left-right symmetrical structure, including the micro-jet flow into the oral cavity 1, the micro-jet nozzle flow channel 2, and the sound wave control tube. 3. Bifurcated flow channel 4 , main jet inflow mouth 5 , main jet nozzle flow channel 6 , jet control port 7 , oscillation cavity 8 , multi-pipe bifurcated flow channel 9 , exhaust port 10 and exhaust channel 20 .

As shown in FIG. 3 , the upper cover 12 is covered on the bottom plate, and the upper cover 12 is provided with two through holes for installing the microjet inlet pipe 13 and the main jet inlet pipe 16 ; the inlet pipe 17 is installed outside the upper cover 12 , the inlet pipe 17 is communicated with the micro-jet inlet pipe 13 and the main jet inlet pipe 16 through the elbow 14 and the tee 15; the tail of the bottom plate is provided with a plurality of inclined exhaust channels 20 running through the bottom of the bottom plate, and the exhaust channels 20 It communicates with the exhaust port 10 .

As shown in FIG. 4 , the cold air recovery device 21 includes a cold air outlet 23 and a cold air outlet 22 . The plurality of exhaust passages 20 are all communicated with the cold air outlet 23 , and the cold air is discharged from the cold air outlet 22 .

The working principle of the utility model is shown in Figure 1, and the details are as follows: the same gas source fluid with the total pressure of the main jet enters the micro-jet and flows into the oral cavity 1 from the inlet pipe 17 and the micro-jet inlet pipe 13, and then enters the micro-jet nozzle flow channel 2 , and then switch the pressure signal of the sonic control pipes 3 on both sides to make the micro-jet enter the bifurcated channel 4, and the micro-jet becomes the excitation source of the main jet; the main jet flows from the inlet pipe 17 and the main jet inlet pipe 16 into the oral cavity through the main jet 5 Enter the main jet nozzle flow channel 6, and then enter the oscillation cavity 8 through the jet control port 7. The jet control port is located at the front end of the oscillator 8 and the end of the main jet nozzle flow channel 6. The micro-jet injected by the jet control port 7 carries out the main jet. Push-pull makes the main jet oscillate, and then enters the multi-tube bifurcated flow channel 9 from the oscillating cavity 8 . The split-split angle structure with the acute angle at the front end of the multi-pipe branched flow channel 9 can ensure that all the jets of the Coanda wall flow into the corresponding flow channel. The oscillating jet generator corresponds to the jet wall on both sides, and extends out of 5 bifurcated flow channels. At the backward extension of the five flow channels, the position before the receiving tube 11 is symmetrically divided by 10° to 50°. The flow channel is passed to the cold air recovery device 21 through the exhaust channel 20 formed obliquely downward at 45°. The cold air is collected in the outlet cavity 23 , and then flows out from the cold air outlet 22 .

The high-pressure gas flows from the micro-jet into the oral cavity 1 and the main jet into the oral cavity 5 and enters the flow channel 19 at the same time. A pressure difference is formed at the openings on both sides of the mouth. Under the action of the pressure difference, the main jet periodically switches the Coanda, and the jet enters the two flow channels in turn.

The outlets of the two flow channels facing the oscillating jet generator are the jet control ports 7 . The oscillating jet generator corresponds to the jet wall on both sides, and extends out five bifurcated flow channels. At the backward extension of the five flow channels, there are corresponding five receiving tubes 11 at the ends corresponding to the gas wave tube, and the pulse jet cycle The gas is incident into the gas wave tube. Each pulse jet will compress the original gas in the tube, forming a contact surface between the two gases. In front of the contact surface, a series of compression waves will be generated, which will converge into shock waves due to the continuous increase of the local speed of sound. Forward. During the stroke swept by the shock wave, the gas pressure and temperature jump, that is, the jet is rapidly compressed, and the energy is transferred to the stagnant gas in the tube by means of the wave system, and is emitted to the environment through the tube wall. When the pulse jet stops, an expansion wave will be generated at the nozzle to move inward, sweeping the jet gas behind the contact surface, reducing its temperature and pressure and other parameters. Under the action of high pressure, the exhaust port 10 is provided at the lower end of the position of the multi-pipe branched flow channel 9 at the front end of the receiving pipe 11 at a 45° angle, and the exhaust port 10 flows through the exhaust channel 20 to the cold air outlet port 23 with relatively low pressure for collection. , and then flows out from the cold air outlet 22 to complete the cooling.

Claims (5)

1. The self-excitation micro-jet control multi-tube oscillator is characterized by comprising an oscillation machine body (18) and a cold air recoverer (21);

the oscillating machine body (18) comprises a bottom plate, an upper cover (12), a micro-jet inlet pipe (13), an elbow (14), a tee joint (15), a main jet inlet pipe (16), an inlet pipe (17), a pipe fixing device (24) and a receiving pipe (11); the upper surface of the bottom plate is provided with different cavities and runners, the runners (19) of the oscillating machine body (18) are formed after being communicated with each other, the runners (19) are of a bilateral symmetry structure and comprise a micro-jet inlet cavity (1), a micro-jet nozzle runner (2), a sound wave control tube (3), a bifurcation runner (4), a main jet inlet cavity (5), a main jet nozzle runner (6), a jet control port (7), an oscillating cavity (8), a multi-pipe bifurcation runner (9), an exhaust port (10) and an exhaust channel (20); the sound wave control tube (3) is positioned at the front end of the oscillating machine body (18) and is encircled into a square ring-shaped flow channel, the micro-jet inlet cavity (1) and the micro-jet nozzle flow channel (2) are positioned in a square ring encircled by the sound wave control tube (3), one end of the micro-jet nozzle flow channel (2) is communicated with the micro-jet inlet cavity (1), and the other end of the micro-jet nozzle flow channel is communicated with the middle position of one edge of the sound wave control tube (3); the forked flow channel (4) is of a bilaterally symmetrical structure and is enclosed into a drop-shaped annular flow channel, the left part and the right part respectively comprise a straight line section and a bent section, the straight line section and the bent section are communicated end to end, the outer side ends of the two straight line sections are intersected at the middle position of one edge of the sound wave control tube (3), so that the forked flow channel (4) is communicated with the micro-jet inlet cavity (1) and the micro-jet nozzle flow channel (2), and the outer side ends of the bent section are intersected at the jet control port (7); the main jet inlet cavity (5) and the main jet nozzle flow channel (6) are positioned in a drop-shaped ring enclosed by the forked flow channel (4), one end of the main jet nozzle flow channel (6) is communicated with the main jet inlet cavity (5), and the other end of the main jet nozzle flow channel is communicated with the jet control port (7); the oscillation cavity (8) and the multi-pipe bifurcation flow channel (9) are positioned at the rear end of the oscillation machine body (18), one end of the oscillation cavity (8) is communicated with the jet flow control port (7), and the other end of the oscillation cavity is communicated with the front end of the multi-pipe bifurcation flow channel (9); the tail part of the oscillating machine body (18) is provided with a plurality of exhaust ports (10), and the exhaust ports (10) are respectively communicated with each branch at the rear end of the multi-pipe branch flow passage (9); the receiving pipe (11) is arranged on the exhaust port (10) from the outer side of the tail part of the oscillating machine body (18) and is fixed through a pipe fixing device (24);

the upper cover (12) covers the bottom plate, two through holes are formed in the upper cover (12) and respectively correspond to the micro-jet inlet cavity (1) and the main-jet inlet cavity (5), a micro-jet inlet pipe (13) and a main-jet inlet pipe (16) are respectively installed on the through holes, the micro-jet inlet pipe (13) is communicated with the micro-jet inlet cavity (1), and the main-jet inlet pipe (16) is communicated with the main-jet inlet cavity (5); the inlet pipe (17) is arranged outside the upper cover (12), and the inlet pipe (17) is communicated with the micro-jet inlet pipe (13) and the main jet inlet pipe (16) through an elbow (14) and a tee joint (15);

the tail part of the bottom plate is provided with a plurality of inclined exhaust channels (20) which penetrate through the bottom of the bottom plate, the exhaust channels (20) correspond to the exhaust ports (10), and the exhaust channels and the exhaust ports are communicated with each other;

the cold air recoverer (21) is arranged at the bottom of the tail end of the oscillating machine body (18) and comprises a cold air outlet cavity (23) and a cold air outlet (22), and the cold air outlet cavity (23) is communicated with the cold air outlet (22); the plurality of exhaust channels (20) are communicated with a cold air outlet cavity (23), and cold air is exhausted from a cold air outlet (22);

the bottom plate, the upper cover (12) and the cold air recoverer (21) are fixed through bolts (25).

2. The self-excited microjet control multi-tube oscillator according to claim 1, wherein the inclination angle of the exhaust channel (20) is 45 °, and the angle between each bifurcation of the multi-tube bifurcated flow passage (9) is 10 ° to 50 °.

3. The self-excited microjet control multitube oscillator according to claim 1 or 2, wherein the material of the oscillating body (18) is an acrylic plate or a metal, processed by laser cutting, and slowly transits to a circular section at the position of the rectangular section of the oscillating jet outlet.

4. A self-exciting microjet control multi-tube oscillator according to claim 1 or 2, characterised in that the length of the terminal extension of the receiving tube (11) is determined by the actual requirements, with a pipe joint for external connection.

5. A self-exciting microjet control multi-tube oscillator according to claim 3, characterised in that the length of the terminal extension of the receiving tube (11) is determined by the actual requirements, with a pipe joint for external connection.

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