Aeration enhanced cavitation jet device and working method

Abstract

The invention discloses an aeration enhanced cavitation jet device and a working method in the field of cavitation, air enters from an air inlet and then enters a space between an upper cylindrical pore plate and a lower cylindrical pore plate from an air injection hole, and meanwhile, high-pressure water rushes into the space between the upper cylindrical pore plate and the lower cylindrical pore plate from a high-pressure water inlet and is preliminarily mixed with the air; air is fed into the lower aeration box by the air injection pipe, and a first-stage cavitation enhancement effect is completed between the upper cylindrical pore plate and the lower cylindrical pore plate by the high-pressure water and the air; the preliminarily mixed high-pressure water passes through a large cavitation nozzle and a small cavitation nozzle to complete a second-stage cavitation enhancement effect, and a propeller rotates to enable the water and the air to be mixed more sufficiently, so that a third-stage cavitation enhancement effect is completed; the high-speed jet flows to an outlet in the bottom of the aeration device through a bracket arm to finish a fourth-stage cavitation enhancement effect; multi-stage enhancement is adopted, enhancement is carried out at multiple positions, the cavitation intensity is made to change within a certain range, and the cavitation efficiency and controllability are improved.

Description

Technical Field

[0001] The invention relates to the technical field of cavitation, and in particular to a method and a device for enhancing cavitation effect through aeration and submerged cavitation nozzles. Background Art

[0002] In some industrial fields, cavitation technology can well meet the requirements of high efficiency and environmental protection. When the pressure of the fluid medium is lower than the saturated vapor pressure, a large number of bubbles will precipitate. When these bubbles enter the high-pressure area, they will quickly collapse and produce local high pressure, high temperature and high-speed jets. The temperature can reach 1900-5200K, the pressure can reach Gpa level, and the micro-flow speed can reach 100m / s. This is the cavitation effect. The energy generated by cavitation can quickly decompose organic matter and give plasticity to objects. Therefore, the cavitation effect is widely used in sewage treatment, metallurgy, etc., but the efficiency of cavitation directly using ordinary fluid media is not high.

[0003] At present, the commonly used methods for enhancing cavitation are: changing the structure of the centrifugal pump, artificially setting a low-pressure and high-speed state, and cooling, etc. These methods for enhancing cavitation are costly, have low cavitation efficiency, and fail to achieve environmental protection. The patent publication number is CN109824152A, and the name is "A cavitation jet ozone degradation oxygenation device for marine aquaculture", which includes a nozzle, an air suction chamber, an air suction pipe, a self-excited oscillation chamber, a throat and a diffuser, and the outside of the air suction chamber is provided with an air suction pipe and a liquid inlet, the nozzle is connected to the liquid inlet of the air suction chamber, the air suction chamber is connected to the inlet of the self-excited oscillation chamber, the throat is connected to the outlet of the self-excited oscillation chamber, the inlet of the diffuser is connected to the outlet of the throat, the water pump sucks the working water in the aeration tank, and the working water is pressurized and ejected from the nozzle, and ozone is sucked into the air suction chamber through the air suction pipe, mixed with water and enters the self-excited oscillation chamber to form a pulsed cavitation jet, and the self-excited oscillation chamber is used to convert the constant jet into a pulsed jet. This cavitation enhancement only occurs at a single location, and it is difficult to change the degree of enhancement for application in various occasions, and the controllability is low. Summary of the invention

[0004] The purpose of the present invention is to solve the above problems existing in the prior art and to provide an aeration-enhanced cavitation jet device and a working method, which adopts multi-stage enhancement and the enhancement effect occurs at multiple positions of the device to improve controllability.

[0005] The technical solution adopted by the aeration-enhanced cavitation jet device described in the present invention is: water in the water tank enters the aeration device after passing through a high-pressure water pump, and the air flow enters the aeration device after passing through an air compressor. The outlet opened at the bottom of the aeration device is connected to the inlet of a submerged cavitation nozzle, and the submerged cavitation nozzle is submerged above the water surface of the water tank. The aeration device includes a sealed cavity formed by an upper aeration box and a lower aeration box that are matched and sealed up and down, and an upper cylindrical orifice plate, an air injection pipe, a lower cylindrical orifice plate, a large cavitation nozzle and a small cavitation nozzle are arranged inside the sealed cavity; an air inlet is opened at the top of the upper aeration box, and the upper cylindrical orifice plate is located directly below the air inlet, and the outer wall of the upper cylindrical orifice plate is fixedly connected to the inner wall of the upper aeration box; the lower cylindrical orifice plate is located directly below the upper cylindrical orifice plate, and the space between the upper cylindrical orifice plate and the lower cylindrical orifice plate is 400 mm / s. A high-pressure water inlet is provided on the side wall of the upper aeration box between the cylindrical orifice plates; a plurality of circles of injection holes and injection pipes arranged in a circular array are provided on the upper cylindrical orifice plate, the injection holes penetrate the upper cylindrical orifice plate, the injection pipe passes downward through the lower cylindrical orifice plate and extends to the top of the lower aeration box, an air outlet hole in the lower aeration box is provided on the bottom side wall of the injection pipe, the bottom of the injection pipe is closed, and a plurality of circles of large cavitation nozzles and small cavitation nozzles distributed in a circular array are provided on the lower cylindrical orifice plate; a propeller is provided in the upper part of the lower aeration box, the propeller is connected to a vertical main shaft through a bearing, the main shaft is located on the central axis of the upper aeration box and the lower aeration box, the bottom end of the main shaft is fixedly connected to the inner wall of the lower aeration box through a bracket, the bracket is composed of three double-wing-shaped bracket arms, and the lower aeration box is a cone with a large top and a small bottom.

[0006] Furthermore, an anti-backflow device is provided in the air injection pipe near the top of the air outlet, and the anti-backflow device consists of a small steel ball, a spring and a baffle. The small steel ball can move up and down in the air injection pipe. The baffle is a through cone plate with a smaller upper hole and a larger lower hole. The lower end of the baffle is fixedly connected to the inner wall of the air injection pipe. The diameter of the upper hole is smaller than the diameter of the small steel ball. A spring is installed at the bottom of the air injection pipe, and the top of the spring is fixedly connected to the small steel ball. When the airflow compresses the spring downward, the bottom end of the small steel ball is always located above the center of the air outlet.

[0007] Furthermore, the cross section of the gas injection pipe decreases in a step-wise manner from top to bottom.

[0008] Furthermore, a backflow prevention device with a similar structure is provided at the bottom end of the air injection hole.

[0009] Furthermore, the large cavitation nozzle and the small cavitation nozzle are alternately arranged in the inner and outer directions, the two have the same height, and the inlets are connected to the contraction tube, the throat tube and the diffusion tube in sequence.

[0010] Furthermore, the inlet inner diameter of the large cavitation nozzle is 2-3 times that of the small cavitation nozzle, the maximum inner diameter of the contraction tube of the large cavitation nozzle is 2-3 times that of the small cavitation nozzle, the throat inner diameter of the large cavitation nozzle is 1.5 times that of the small cavitation nozzle, and the throat length of the small cavitation nozzle is longer than that of the large cavitation nozzle.

[0011] The technical solution adopted by the working method of the aeration enhanced cavitation jet device of the present invention comprises the following steps:

[0012] Step A): air enters from the air inlet and enters the space between the upper cylindrical orifice plate and the lower cylindrical orifice plate from the air injection hole. At the same time, high-pressure water rushes into the space between the upper cylindrical orifice plate and the lower cylindrical orifice plate from the high-pressure water inlet and is preliminarily mixed with the air. The air injection pipe sends the air into the lower aeration box. The high-pressure water and air complete the first stage of cavitation enhancement between the upper cylindrical orifice plate and the lower cylindrical orifice plate.

[0013] Step B): The preliminarily mixed high-pressure water passes through the large cavitation nozzle and the small cavitation nozzle to form high-speed jets and cavitation bubbles, completing the second-stage cavitation enhancement effect, so that the high-pressure water is evenly distributed in the lower aeration box;

[0014] Step C): The air passing through the air injection pipe passes through the upper cylindrical orifice plate and the lower cylindrical orifice plate to further mix with the high-pressure water. Under the action of the high-speed jet formed by the large cavitation nozzle and the small cavitation nozzle, the propeller rotates to make the water and air mix more fully, completing the third-stage cavitation enhancement effect;

[0015] Step D): The high-speed jet passes through the support arm, the flow rate increases, the pressure decreases, negative pressure is generated, and flows to the outlet at the bottom of the aeration device, completing the fourth stage of cavitation enhancement.

[0016] After the present invention adopts the above scheme, the beneficial effects are:

[0017] 1. The air injection pipe used in the device of the present invention utilizes the Bernoulli principle to reduce the water temperature automatically, rather than by artificial cooling, saving manpower and material resources, and the temperature reduction range can be controlled by increasing the number of air injection pipes and their diameter lengths, which is controllable. At the same time, it also creatively utilizes the principle of high air content at low water temperature, does not require too much energy input, greatly reduces costs, and improves cavitation efficiency.

[0018] 2. The propeller installed in the aeration device of the present invention can rotate at high speed without any power under the drive of high-speed jet, and at the same time, it also generates cavitation at the back of the blade while generating low pressure, and can also stir the high-pressure water to make it better mixed with air. The whole process does not require human participation, let alone any energy, and is highly efficient and energy-saving.

[0019] 3. The support structure in the device of the present invention imitates the principle of the wing and uses the Bernoulli principle to accelerate the flow rate of the high-speed jet when it flows through the support, generate low pressure, and generate cavitation at the same time. The lower aeration box is processed into a cone shape, which accelerates the convergence of cavitation, effectively reduces the problem that cavitation may break when moving, and enhances the cavitation effect.

[0020] 4. The device of the present invention adopts two different types of cavitation nozzles, large and small, and utilizes different throat inner diameters to make water jet speeds different, thereby allowing the water flow to be more evenly distributed in the lower aeration box, which can be better mixed with the air and can also better play the role of the propeller.

[0021] 5. The entire enhancement effect is divided into four-level cavitation enhancement and final cavitation, which is enhanced at multiple positions. The graded working structure allows the strength of cavitation to vary within a certain range, so that the device can be applied to more types of work that requires the use of cavitation.

[0022] 6. The final cavitation effect uses a submerged cavitation nozzle instead of an ordinary nozzle. A low-pressure vortex is generated through shearing action, and cavitation bubbles are generated from the low-pressure vortex through a chain reaction, eventually forming a cavitation cloud, which enhances the intensity of the final cavitation effect. The shearing action of the submerged nozzle can also deliver the cavitation bubbles to the work site faster and more safely. Its performance is far better than that of an ordinary nozzle.

[0023] 7. The present invention allows water flow to be mixed with air for aeration, thereby increasing the dissolved oxygen content in the water. The abundant bubbles can increase the contact area with water, improve the dissolved oxygen efficiency, and ultimately increase the gas content to achieve the purpose of enhancing cavitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0025] Figure 1 This is a schematic diagram of the overall structural connection of an aeration-enhanced cavitation jet device of the present invention;

[0026] Figure 2 for Figure 1 A magnified view of the internal structure of the aeration device;

[0027] Figure 3 for Figure 2 A magnified view of the three-dimensional structure of the upper cylindrical orifice plate, the gas injection pipe and the gas injection hole;

[0028] Figure 4 for Figure 3 A magnified view of the bottom structure of the middle injection pipe;

[0029] Figure 5 for Figure 2 A magnified view of the three-dimensional structure of the lower cylindrical orifice plate;

[0030] Figure 6 for Figure 2 The enlarged view of the large cavitation nozzle structure and some dimension markings;

[0031] Figure 7 for Figure 2The enlarged diagram of the small cavitation nozzle structure and the partially dimensioned diagram;

[0032] Figure 8 for Figure 2 A magnified view of the support structure;

[0033] Fig. 9 for Figure 2 Schematic diagram of the internal working status of the aeration device shown.

[0034] In the figure: 1. air compressor; 2. high-pressure air storage system; 3. air source distribution box; 4. aeration box; 5. vortex flowmeter; 6. pressure regulating valve; 7. high-pressure water pump; 8. filter; 9. return line; 10. water tank; 11. submerged cavitation nozzle; 12. external bracket; 13. air injection pipe; 14. small cavitation nozzle; 15. threaded hole of air injection pipe; 16. large cavitation nozzle; 17. upper cylindrical orifice plate; 18. upper aeration box; 19. air injection hole; 20. lower cylindrical orifice plate; 21. air Air inlet; 22. High-pressure water inlet; 23. Lower aeration box; 24. Bolts; 25. Upper propeller; 26. Lower propeller; 27. Upper bearing; 28. Lower bearing; 29. ​​Bracket; 30. Aeration device outlet; 31. Main shaft; 32. First-stage cavitation; 33. Second-stage cavitation; 34. Third-stage cavitation; 35. First-stage, second-stage and third-stage mixed cavitation; 36. Steel ball; 37. Baffle; 38. Spring; 39. Air outlet of air injection pipe; 41. Master control system; 42. Bracket arm. DETAILED DESCRIPTION

[0035] See also Figure 1The present invention discloses an aeration-enhanced cavitation jet device, which includes a water flow path, an air flow path, and an aeration device. The water flow path is a water tank 10, a filter 8, a high-pressure water pump 7, a pressure regulating valve 6, a vortex flowmeter 5, an aeration device 4, and a submerged cavitation nozzle 11 connected in sequence through a return line 9. The water flowing out of the water tank 10 first enters the filter 8 through the return line 9. After a filtering process, the water flows into the high-pressure water pump 7 for pressurization. The high-pressure water pump 7 compresses the water into high-pressure water and provides power for the high-pressure water to flow. The water reaches the pressure regulating valve 6. After receiving the current signal from the master control system 41, the pressure regulating valve 6 will drive the valve to change the cross-sectional area between the valve core and the valve seat, thereby controlling the flow rate, flow rate, and pressure of the water flow to achieve the desired purpose. The regulated high-pressure water then flows through the vortex flowmeter 5, which records the flow rate at this time and then enters the aeration device 4. The airflow path is connected to the air compressor 1, the high-pressure air storage system 2, the air source distribution box 3, the aeration device 4, the submerged cavitation nozzle 11 and the water tank 10 in sequence. The starting point of the air path is the air compressor 1, the outlet of the aeration device 4 is connected to the inlet of the submerged cavitation nozzle 11, and finally returns to the water tank 10 through the submerged cavitation nozzle 11, and the submerged cavitation nozzle 11 is submerged above the water surface. The air compressor 1 is divided into a volumetric type and a velocity type. After entering the air compressor 1, the air is compressed into high-pressure air, and the mechanical energy is converted into the pressure energy of the high-pressure air, providing the original power for the airflow path. After the high-pressure air is formed, it will reach the high-pressure air storage system 2, which is equipped with a one-way valve and a volume valve. The one-way valve prevents air from flowing back, and the volume valve controls the release of gas. After the air is stored for a period of time, it will be released and flow to the air source distribution box 3 for the last treatment. The air source distribution box 3 is equipped with a separation device and a filter device, which can achieve the functions of air decompression, water vapor separation and filtering of air impurities. The treated air will enter the aeration device 4 for the next step.

[0036] The master control system 41 is connected to the filter 8, the high-pressure water pump 7, the pressure regulating valve 6, the vortex flowmeter 5, the aeration device 4, the air compressor 1, the high-pressure air storage system 2 and the air source distribution box 3, and enables the entire process to operate automatically by transmitting signals.

[0037] See also Figure 2The aeration device 4 shown as having an enhanced effect comprises: an air injection pipe 13, a small cavitation nozzle 14, an air injection pipe threaded hole 15, a large cavitation nozzle 16, an upper cylindrical orifice plate 17, an upper aeration box 18, an air injection hole 19, a lower cylindrical orifice plate 20, an air inlet 21, a high-pressure water inlet 22, a lower aeration box 23, bolts 24, an upper propeller 25, a lower propeller 26, an upper bearing 27, a lower bearing 28, a bracket 29, an aeration device outlet 30 and a main shaft 31. The upper aeration box 18 and the lower aeration box 23 are matched and sealed to form a sealed cavity. The upper cylindrical orifice plate 17, the air injection pipe 13, the lower cylindrical orifice plate 20, the large cavitation nozzle 16 and the small cavitation nozzle 14 are arranged inside the sealed cavity.

[0038] The bottom of the lower aeration box 23 is provided with an aeration device outlet 30. An air inlet 21 is provided at the top of the upper aeration box 18, and the air inlet 21 is connected to the air source distribution box 3 through a pipeline. The high-pressure air compressed by the air compressor 1 enters the upper aeration box 18 downward from the air inlet 21 at the top. Directly below the air inlet 21 is an upper cylindrical orifice plate 21, the outer wall of which is consistent with the inner wall of the upper aeration box 18 and is fixedly connected to the inner wall of the upper aeration box 18. A space should be left between the upper cylindrical orifice plate 21 and the air inlet 21 for storing air.

[0039] Directly below the upper cylindrical orifice plate 17 is the lower cylindrical orifice plate 20, which is located at the connection between the upper aeration box 18 and the lower aeration box 23. The space volume between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20 is about two-thirds of the space volume of the upper aeration box 18. A high-pressure water inlet 22 is opened on the side wall of the upper aeration box 18 between the cylindrical orifice plate 17 and the lower cylindrical orifice plate 20. The high-pressure water inlet 22 is between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20, and the high-pressure water pressed by the high-pressure water pump 7 can directly enter the space between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20 from the high-pressure water inlet 22.

[0040] See also Figure 3, a plurality of gas injection holes 19 and gas injection pipes 13 arranged in a circular array are provided on the upper cylindrical orifice plate 17, and the central axis of the upper cylindrical orifice plate 17 is the innermost, and the gas injection holes 19 and the gas injection pipes 13 are alternately arranged in the inner and outer directions. The gas injection holes 19 penetrate the upper cylindrical orifice plate 17, and the gas injection holes 19 directly send the upper air downward into the space between the cylindrical orifice plate 17 and the lower cylindrical orifice plate 20 to be preliminarily mixed with the high-pressure water. The gas injection pipe 13 extends downward to connect and pass through the lower cylindrical orifice plate 20, and extends into the top of the lower aeration box 23. An air outlet 39 is opened at the bottom side wall of the air injection pipe 13, and the bottom of the air injection pipe 13 is closed. The air outlet 39 is in the lower aeration box 23, and the air injection pipe 13 directly sends the air into the lower aeration box 23 over the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20. The cross section of the gas injection pipe 13 decreases in steps from top to bottom, which utilizes the Bernoulli principle. The purpose is to increase the flow rate of the airflow as the cross section of the pipe decreases. The increase in the flow rate of the airflow will reduce the temperature of the pipe wall, and then reduce the temperature of the surrounding water through heat transfer, ultimately achieving the purpose of increasing the gas content.

[0041] See also Figure 4 In order to prevent the backflow of liquid and gas, an anti-backflow device is installed in the gas injection pipe 13 near the top of the gas outlet 39. The anti-backflow device consists of a small steel ball 36, a spring 38 and a baffle 37. The small steel ball 36 is a steel ball with a radius smaller than the minimum radius of the gas injection pipe 13, so that the small steel ball 36 can move up and down in the gas injection pipe 13 without affecting the air flow from top to bottom. The best position of the small steel ball 36 is in the last section of the tube cavity with the smallest radius at the bottom of the gas injection pipe. At the same time, a circle of baffles 37 is installed at the top of this section of the tube cavity. The lower end of the baffle 37 is fixedly connected to the inner wall of the gas injection pipe 13. The baffle 37 is a through cone plate with a smaller upper hole and a larger lower hole. The diameter of the upper hole is smaller than the diameter of the small steel ball 36, which can hold the small steel ball 36. A spring 38 is installed at the bottom of the gas injection pipe 13. The top of the spring 38 is fixedly connected to the small steel ball 36, and the bottom of the spring 38 is supported on the bottom wall of the gas injection pipe 13. In this way, when the airflow flows downward from the top of the air injection pipe 13, it passes through the baffle 37 downward, and the spring 38 is compressed downward by the airflow pressure, pushing the small steel ball 36 downward and disengaging the baffle 37, so that the airflow can flow out from the air outlet 39, and the airflow flows into the lower aeration box 23 from the air outlet 39. When there is too much water flow in the space of the lower aeration box 23, it will cause water to flow back into the air injection pipe 13. At this time, the small steel ball 36 needs to move upward under the thrust of the water flow, and finally be stuck by the baffle 37, so that the water flow is blocked from flowing back upward, effectively preventing the backflow. In order to achieve the ideal anti-backflow effect, the spring 38 is required to have an appropriate stiffness coefficient, so that the length of the compression when it is subjected to the upper air pressure is to make the bottom of the small steel ball 36 always located above the center of the air outlet 39, otherwise the water flow may pass over the small steel ball 36, which greatly weakens the anti-backflow effect.

[0042] Similarly, a backflow prevention device with a similar structure is installed at the bottom of the air injection hole 19. The radius of the small steel ball 36 in the backflow prevention device is slightly smaller than the radius of the bottom of the air injection hole 19, which prevents excessive water flow between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20 from causing water to flow back from the air injection hole 19 into the air storage space on the upper layer of the upper aeration box 18.

[0043] See also Figure 5 Like the upper cylindrical orifice plate 17, the lower cylindrical orifice plate 20 is provided with a plurality of large holes and small holes of different sizes distributed in a circular array. A large cavitation nozzle 16 is installed at the large hole, and a small cavitation nozzle 14 is installed at the small hole; the large cavitation nozzle 16 and the small cavitation nozzle 14 are arranged alternately in the inner and outer directions. The inner diameters of the large cavitation nozzle 16 and the small cavitation nozzle 14 are different. A gas injection pipe threaded hole 15 is provided between the large cavitation nozzle 16 and the small cavitation nozzle 14, the purpose of which is to fix the gas injection pipe 13 passing through the lower cylindrical orifice plate 20. Starting from the central axis of the lower cylindrical orifice plate 20, the small cavitation nozzle 14, the gas injection pipe threaded hole 15, and the large cavitation nozzle 16 are arranged alternately in the radial direction, and extend in the radial direction.

[0044] After the high-pressure water and air are preliminarily mixed between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20, they will pass through the large cavitation nozzle 16 and the small cavitation nozzle 14 on the lower cylindrical orifice plate 20 and enter the lower aeration box 23. Due to the different inner diameters of the large cavitation nozzle 16 and the small cavitation nozzle 14, the high-speed jet flow rate can be different, and then the spraying distance can be different, so that the mixing of air and water flow can be more uniform.

[0045] See also Figure 6 and Figure 7The large cavitation nozzle 16 and the small cavitation nozzle 14 shown have the same upper and lower heights, both L. The inlets of the large cavitation nozzle 16 and the small cavitation nozzle 14 are connected to the contraction tube, the throat and the diffusion tube in sequence. The inlet inner diameter of the large cavitation nozzle 16 is d11, the maximum inner diameter of its contraction tube is d12, the inner diameter of the throat is d13, the height of the throat is h1, and the maximum inner diameter of the diffusion tube is d14. The inlet inner diameter of the small cavitation nozzle 14 is d21, the maximum inner diameter of its contraction tube is d22, the inner diameter of the throat is d23, the height of the throat is h2, and the maximum inner diameter of the diffusion tube is d24. Among them, the inlet inner diameter d11 of the large cavitation nozzle 16 is 2-3 times the inlet inner diameter d21 of the small cavitation nozzle 14, the maximum inner diameter d12 of the contraction tube of the large cavitation nozzle 16 is also 2-3 times the maximum inner diameter d21 of the contraction tube of the small cavitation nozzle 14, the throat inner diameter d13 of the large cavitation nozzle 16 is 1.5 times the throat inner diameter 23 of the small cavitation nozzle 14, and the difference between the throat inner diameters of the large and small cavitation nozzles should not be too large, in order to make the flow difference of the water passing through the large and small cavitation nozzles not too large, so as to make the water flow reaching the lower aeration box 23 more evenly distributed. In addition, the throat length h2 of the small cavitation nozzle 14 is slightly longer than the throat length h1 of the large cavitation nozzle 16, in order to make the faster water flow rate therein more uniform.

[0046] The circumference of the large cavitation nozzle 16 and the small cavitation nozzle 14 is surrounded by threads and fixed on the lower cylindrical orifice plate 20 by threads, which is convenient for installation. In addition, the diffusion pipe is the outlet of the large cavitation nozzle 16 and the small cavitation nozzle 14, which is conical, in order to prevent the high-speed jet from exploding quickly when it flows out of the nozzle, resulting in a large reduction in the number of cavitation bubbles.

[0047] See also Figure 2 The lower cylindrical orifice plate 20 is at the boundary between the upper aeration box 18 and the lower aeration box 23, and the upper aeration box 18 and the lower aeration box 23 are fixedly connected by bolts 24. The lower aeration box 23 is a cone with a larger upper portion and a smaller lower portion.

[0048] A propeller is provided at the upper part of the lower aeration box 23, and the propeller is connected to a vertical main shaft 31 through a bearing. The main shaft 31 is located on the central axis of the upper aeration box 18 and the lower aeration box 23, and the bottom end of the main shaft 31 is fixedly connected to the inner wall of the lower aeration box 23 through a bracket 29. Preferably, the present invention adopts two upper and lower propellers, namely an upper propeller 25 and a lower propeller 26. The upper propeller 25 and the lower propeller 26 are connected to the vertical main shaft 31 through corresponding upper bearings 27 and lower bearings 28, respectively. Each propeller has three propeller blades, and the adjacent two propeller blades are 120 degrees. When the six blades are viewed from above, they are staggered in pairs at 60 degrees. The length of the propeller blade is about two-thirds of the radius of the lower cylindrical orifice plate 20. When the high-speed jet just flows into the lower aeration box 23, the upper propeller 25 and the lower propeller 26 will rotate rapidly under the impact of the high-speed jet. The propeller blades rotating at high speed will produce a large number of cavitations on the back of the blades, further increasing the number of cavitations. At the same time, high-speed rotation will produce a low-pressure environment to protect the cavitations from bursting and enhance water-gas mixing through high-speed stirring.

[0049] The main shaft 31 is located in the middle section of the lower aeration box 23, and its upper part is connected to the upper propeller 25 and the lower propeller 26 through the upper bearing 27 and the lower bearing 28, and its lower end is fixedly connected to the bracket 29. Figure 8 As shown, the structure of the bracket 29 is a symmetrical structure modeled after a double wing, and is composed of three double wing-shaped bracket arms 42. When water flows from top to bottom through the bracket arms 42, due to the wing principle, the water flow rate will be accelerated, negative pressure will be generated, and bubble rupture will be reduced. The cross-section of the bracket arm 42 is a symmetrical pattern, that is, the so-called double wing structure. The top of the bracket 29 is fixedly connected to the bottom end of the main shaft 31, and the lower part of the bracket 29 is fixedly connected to the inner wall of the lower aeration box 23 through the bracket arm 42. The upper aeration box 18 is connected to the lower aeration box 23 by bolts 24, and the shape of the lower aeration box 23 is conical, which allows the high-speed jet to quickly converge to the outlet 30 of the aeration device at the bottom. Because cavitation may rupture during movement, the conical structure can increase the movement speed of cavitation, thereby reducing cavitation losses.

[0050] The high-speed jet flowing out of the aeration device 4 will flow through the submerged cavitation nozzle 11, completing the last stage of cavitation, and the water will flow back to the water tank 10 to achieve water recycling. The nozzle of the submerged cavitation nozzle 11 is submerged above the water surface, and the peripheral static water can be sheared immediately when the high-pressure jet rushes out of the submerged cavitation nozzle 11. In comparison, ordinary non-submerged cavitation nozzles first impact the water surface of the water tank when the high-speed jet rushes out of the nozzle. The impact will reduce the water flow speed and force the water flow to explode, and the cavitation will also explode during the impact. Therefore, the submerged cavitation nozzle 11 has obvious advantages. Finally, materials such as metal blocks placed at the bottom of the water tank 10 will be shaped or cut under the cavitation effect.

[0051] When the aeration-enhanced cavitation jet device of the present invention is working, the master control system 41 controls the air compressor 1 and the high-pressure water pump 7 to work simultaneously. Under the action of the air compressor 1, air is sucked in and compressed into high-pressure air, and then transferred to the high-pressure air storage system 2 and stored therein. The stored high-pressure air enters the air source distribution box 3, under the action of which, the purest air source in the high-pressure air is screened out and finally enters the aeration device 4 through the pipeline. Under the action of the high-pressure water pump 7, the water in the water tank 10 flows out from one side of the water tank 10 through the return pipe 9 and flows through the filter 8 for a filtration. The filter 8 can remove most of the impurities in the water. The filtered water will then flow into the high-pressure water pump 7 along the pipeline. Under the action of the high-pressure water pump 7, the high-pressure water flows into the pressure regulating valve 6 through the pipeline, and the pressure of the water flow is adjusted to a suitable range. The high-pressure water with adjusted pressure quickly flows through the vortex flowmeter 5, and finally enters the aeration device 4 through the high-pressure water inlet 26. The vortex flowmeter 5 will record the flow of high-pressure water in real time.

[0052] See also Figure 8 The aeration device 4 is the core device, and its main function is to increase the air content in the water through aeration, further increase the number of cavitation bubbles, so as to achieve the effect of enhancing cavitation. In the aeration device 4, high-pressure water and high-pressure air will intersect and mix. After the air enters from the air inlet 21, it first briefly gathers in the upper space at the top of the upper aeration box 18, and then enters the air injection holes 19 and the air injection pipe 13 located on the upper cylindrical orifice plate 17. On the upper cylindrical orifice plate 17, the air injection holes 19 and the air injection pipe 13 are arranged in a circular array and are distributed at intervals. The air enters the space between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20, that is, the lower space of the upper aeration box 18 from the air injection holes 19. At the same time, the high-pressure water quickly rushes into the space between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20 from the high-pressure water inlet 22 on the side of the upper aeration box 18, and is preliminarily mixed with the air passing through the air injection holes 19 in this space. The bottom of the air injection pipe 13 is connected to the air injection pipe threaded hole 15 on the lower cylindrical orifice plate 20, and the air is directly sent into the lower aeration box 23. The cross-sectional area of ​​the air injection pipe 13 decreases in a step-by-step manner. According to the Bernoulli principle: when the airflow flows from a large aperture to a small aperture, the flow rate will become faster, and the temperature will decrease as the aperture decreases. Therefore, the air flow rate in the air injection pipe 13 will continue to increase, and the temperature of the pipe wall will also decrease. The pipe wall will also reduce the temperature of the surrounding space through heat conduction. At the same time, the pipe wall of the air injection pipe 13 reduces the water temperature around it. The lower the temperature, the higher the gas content of the water. In addition, the initial mixing of high-pressure water and air completes the first stage of cavitation enhancement.

[0053] After the high-pressure water and air complete the first stage cavitation enhancement between the upper cylindrical orifice plate 17 and the lower cylindrical orifice plate 20, they enter the lower aeration box 23 through the large cavitation nozzle 16 and the small cavitation nozzle 14 on the lower cylindrical orifice plate 20. When the high-pressure water flows through the two large and small cavitation nozzles 16 and 14, the speed increases sharply at the throat of the cavitation nozzle to form a high-speed jet. At this time, the water flow pressure is lower than the saturated vapor pressure, and a large number of cavitation bubbles will be formed. This is the second stage cavitation enhancement. The cavitation bubbles produced by the nozzle after the first and second stage cavitation enhancement are the first stage cavitation bubbles 32. At the same time, the throats of the large and small cavitation nozzles are different in thickness, and the high-speed jet speeds formed are different, so the distances of the high-speed jets will also be different, which makes the high-pressure water more evenly distributed in the lower aeration box 23. When the high-pressure water preliminarily mixed with air enters the lower aeration box 23 through the large and small cavitation nozzles 16 and 14, the other air at the top of the aeration box also directly passes through the two cylindrical orifice plates through the air injection pipe 13 to reach here, and is further mixed with the preliminarily mixed high-pressure water. The high-speed jet formed by the preliminarily mixed high-pressure water after passing through the cavitation nozzle has a high speed and strong impact force. Under the action of its strong impact force, the upper propeller 25 and the lower propeller 26 located at the upper part of the lower aeration box 23 begin to rotate at a high speed. The upper and lower propellers 25 and 26 will mix the water and air more fully when rotating. In addition, the high-speed rotation of the propeller will cause the pressure at the back of the blade to drop rapidly, thereby generating second-stage cavitation bubbles 33. These cavitation bubbles 33 will be thrown out in a very short time after being generated, and will mix with the first-stage cavitation bubbles 32, further increasing the number of cavitation bubbles in the high-speed jet, thus completing the third-stage cavitation enhancement effect. At the same time, the high-speed rotating propeller will form a low-pressure environment in the surrounding space. In the low-pressure environment, the cavitation is not easy to expand and rupture under the action of the pressure difference because its internal pressure is not much different from the surrounding low-pressure environment. In this way, the cavitation can be safely moved to the bottom of the lower aeration box 23 under the influence of the high-speed jet. And due to the conical structure of the lower aeration box 23, the high-speed jet will carry the primary and secondary mixed cavitations at a higher speed to converge to the bottom of the device. During the rapid movement, the high-speed jet also passes through the bracket 29 located at the bottom of the device. Due to the double-wing structure of the bracket 29, the water flow will accelerate when passing through the branch of the bracket, and the pressure will decrease, generating negative pressure and reducing the rupture of the cavitation. At the same time, the water flow flowing close to the bracket will quickly reduce its pressure due to its wing-type structure, and then cavitation will occur to produce the third-level cavitation 34. Then, in the low-pressure environment of the bracket, the high-speed jet passes quickly and flows to the outlet 30, thus completing the fourth-level cavitation enhancement. Finally, the high-speed jet having undergone the fourth-stage cavitation enhancement reaches the bottom of the lower aeration box 23 and flows out of the aeration device 4 through the outlet 30 along with the mixed cavities 35 of the first-stage, second-stage and third-stage cavities.

[0054] The high-speed jet flowing out of the aeration device 4 flows into the submerged cavitation nozzle 11 located in the water tank 10 through the pipeline for final cavitation. Different from ordinary cavitation nozzles, the main body of cavitation of submerged cavitation water jet is shear cavitation. When the high-speed jet passes through the submerged cavitation nozzle 11, the speed is the fastest at the throat, forming cavitation bubbles. Due to the inverted cone structure of the cavitation nozzle outlet, the high-speed jet will maintain a high-pressure water beam state when rushing out of the nozzle and is not easy to explode. The high-speed jet carrying cavitation bubbles will have a strong shearing effect with the static liquid in the water tank 10. The jet will entrain the surrounding water, forming a low-pressure vortex structure in the part where the high-speed jet is sheared, and a large number of cavitation bubbles will be bred in the low-pressure vortex area. The cavitation bubbles will gather to form a cavitation cloud and move downstream under the drive of the high-speed jet. During the movement, due to the reduction of the high-speed jet speed, the pressure inside the cavitation bubble increases, the cavitation bubble will continue to expand, and finally collapse, generating high pressure and high temperature. At this time, the components at the bottom of the water tank 10 can use the energy brought by the cavitation bubble rupture to complete the work.

[0055] High-pressure water and high-pressure air are regulated and screened before entering the aeration device 4, ensuring that the water source and air source entering the aeration device 4 have appropriate pressure and flow, and both are filtered to avoid the influence of impurities on cavitation. These processes effectively ensure the quality of cavitation and allow the enhancement to proceed smoothly. In the aeration device 4, the water and gas are mixed twice to complete the first-level enhancement, and then the second-level enhancement is completed through the large and small cavitation nozzles. After that, the third and fourth levels of enhancement are completed in the lower aeration box 23 through the propeller and the double-wing structure bracket respectively. In addition to the four-level enhancement, the device also has multi-level cavitation protection measures. The low-pressure environment formed by the rotation of the propeller and the bracket can well protect the cavitation, and the conical structure of the lower aeration box 23 reduces the loss of cavitation during movement. These protections ensure the effect of the enhancement and also make the device have strong stability. In addition to high efficiency and stability, the internal function of the device does not require human participation, reducing costs while also performing multi-level cavitation, which is environmentally friendly and controllable.

Claims

1. An aeration-enhanced cavitation jet device, wherein water in a water tank enters an aeration device (4) after passing through a high-pressure water pump, and air flows into the aeration device (4) after passing through an air compressor, and an outlet at the bottom of the aeration device (4) is connected to an inlet of a submerged cavitation nozzle (11), and the submerged cavitation nozzle (11) is submerged above the water surface of the water tank, characterized in that: The aeration device (4) comprises a sealed cavity formed by an upper aeration box (18) and a lower aeration box (23) which are joined and sealed together. An upper cylindrical orifice plate (17), an air injection pipe (13), a lower cylindrical orifice plate (20), a large cavitation nozzle (16) and a small cavitation nozzle (14) are arranged inside the sealed cavity. An air inlet (21) is provided at the top of the upper aeration box (8), and the upper cylindrical orifice plate is located directly below the air inlet (21). (21), the outer wall of the upper cylindrical orifice plate (21) is fixedly connected to the inner wall of the upper aeration box (18); the lower cylindrical orifice plate (20) is located directly below the upper cylindrical orifice plate (17), and a high-pressure water inlet (22) is opened on the side wall of the upper aeration box (18) between the upper cylindrical orifice plate (17) and the lower cylindrical orifice plate (20); the upper cylindrical orifice plate (17) is provided with a plurality of gas injection holes (19) and gas injection pipes (13) arranged in a circular array, and the gas injection holes (19) passes through the upper cylindrical orifice plate (17), the air injection pipe (13) passes downward through the lower cylindrical orifice plate (20) and extends to the top of the lower aeration box (23), the bottom side wall of the air injection pipe (13) is provided with an air outlet hole (39) in the lower aeration box (23), the bottom of the air injection pipe (13) is closed, and the lower cylindrical orifice plate (20) is provided with a plurality of large cavitation nozzles (16) and small cavitation nozzles (14) distributed in a circular array; A propeller is provided at the upper part of the lower aeration box (23), and the propeller is connected to a vertical main shaft (31) through a bearing. The main shaft (31) is located on the central axis of the upper aeration box (18) and the lower aeration box (23). The bottom end of the main shaft (31) is fixedly connected to the inner wall of the lower aeration box (23) through a bracket (29). The bracket (29) is composed of three double-wing-shaped bracket arms (42). The lower aeration box (23) is a cone with a larger upper part and a smaller lower part.

2. The aeration-enhanced cavitation jet device according to claim 1, characterized in that: The propeller comprises an upper propeller (25) and a lower propeller (26), which are respectively connected to the main shaft (31) through corresponding upper bearings (27) and lower bearings (28). Each propeller has three propeller blades, two adjacent propeller blades are 120 degrees apart, and the six blades are staggered in pairs at 60 degrees.

3. The aeration-enhanced cavitation jet device according to claim 1, characterized in that: An anti-backflow device is provided in the gas injection pipe (13) near the top of the gas outlet hole (39), and the anti-backflow device is composed of a small steel ball (36), a spring (38) and a baffle (37). The small steel ball (36) can move up and down in the gas injection pipe (13). The baffle (37) is a through cone plate with a smaller upper hole and a larger lower hole. The lower end of the baffle (37) is fixedly connected to the inner wall of the gas injection pipe (13), and the diameter of the upper hole is smaller than the diameter of the small steel ball (36). A spring (38) is installed at the bottom of the gas injection pipe (13), and the top end of the (spring 38) is fixedly connected to the small steel ball (36). When the spring (38) is compressed by the air flow, the bottom end of the small steel ball (36) is always located above the center of the gas outlet hole (39).

4. The aeration-enhanced cavitation jet device according to claim 1, characterized in that: The cross section of the gas injection pipe (13) decreases in a step-like manner from top to bottom.

5. The aeration-enhanced cavitation jet device according to claim 1, characterized in that: The bottom end of the air injection hole (19) is provided with an anti-backflow device with a similar structure.

6. The aeration-enhanced cavitation jet device according to claim 1, characterized in that: The large cavitation nozzle (16) and the small cavitation nozzle (14) are arranged alternately in the inner and outer directions, and both have the same height. The inlets are connected to the contraction tube, the throat tube and the diffusion tube in sequence.

7. The aeration-enhanced cavitation jet device according to claim 6, characterized in that: The inlet inner diameter of the large cavitation nozzle (16) is 2-3 times the inlet inner diameter of the small cavitation nozzle (14), the maximum inner diameter of the contraction tube of the large cavitation nozzle (16) is 2-3 times the maximum inner diameter of the contraction tube of the small cavitation nozzle (14), the throat inner diameter of the large cavitation nozzle (16) is 1.5 times the throat inner diameter of the small cavitation nozzle (14), and the throat length of the small cavitation nozzle (14) is longer than the throat length of the large cavitation nozzle (16).

8. The aeration-enhanced cavitation jet device according to claim 1, characterized in that: The lower cylindrical perforated plate (20) is located at the boundary between the upper aeration box (18) and the lower aeration box (23).

9. The aeration-enhanced cavitation jet device according to claim 1, characterized in that: A space is reserved between the upper cylindrical perforated plate (21) and the air inlet (21) for storing air.

10. A method for operating the aeration-enhanced cavitation jet device according to any one of claims 1 to 8, characterized in that The following steps are involved: Step A): air enters from the air inlet (21) and then enters the space between the upper cylindrical orifice plate (17) and the lower cylindrical orifice plate (20) from the air injection hole (19). At the same time, high-pressure water rushes into the space between the upper cylindrical orifice plate (17) and the lower cylindrical orifice plate (20) from the high-pressure water inlet (22) and is preliminarily mixed with the air. The air injection pipe (13) sends the air into the lower aeration box (23). The high-pressure water and air complete the first stage of cavitation enhancement between the upper cylindrical orifice plate (17) and the lower cylindrical orifice plate (20); Step B): The preliminarily mixed high-pressure water passes through the large cavitation nozzle (16) and the small cavitation nozzle (14) to form high-speed jets and cavitation bubbles, completing the second-stage cavitation enhancement effect, so that the high-pressure water is evenly distributed in the lower aeration box (23); Step C): the air passing through the air injection pipe (13) passes through the upper cylindrical orifice plate (17) and the lower cylindrical orifice plate (20) to be further mixed with the high-pressure water. Under the action of the high-speed jet formed by the large cavitation nozzle (16) and the small cavitation nozzle (14), the propeller rotates to make the water and air mix more fully, thus completing the third-stage cavitation enhancement effect; Step D): The high-speed jet flows through the support arm (42), the flow velocity is accelerated, the pressure is reduced, negative pressure is generated, and the jet flows to the outlet at the bottom of the aeration device (4), completing the fourth stage of cavitation enhancement.

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