Venturi cavitator based on rotational flow-pore plate coupling effect

Abstract

The invention provides a Venturi cavitator based on a rotational flow-pore plate coupling effect, and relates to the technical field of fluid cavitation, the Venturi cavitator comprises an inlet section, a throat part and an expansion section of a Venturi tube body, and a hollow spiral flow deflector is arranged on the inner wall of the inlet section. The spiral flow deflectors enable peripheral fluid close to the inner side wall surface to generate high-speed rotation, a stable rotation effect is formed, and a local low-pressure area is induced in the expansion section, so that pressure recovery caused by cavitation burst is effectively counteracted, the cavitation period interval is shortened, and the continuity of the cavitation process is enhanced; the hollow flow channel reorganizes and accelerates the fluid in the central area, the flow velocity of the throat is effectively improved, and the cavitation intensity is improved. The device is compact in structure and easy to manufacture, can improve cavitation intensity and continuity at the same time, is widely applicable to multiple fields such as sewage degradation, sterilization and disinfection, industrial emulsification, oil-water mixing treatment and the like, and has good application prospects and economic and social benefits.

Description

Technical Field

[0001] The invention belongs to the technical field of fluid cavitation equipment, and in particular relates to a Venturi cavitator based on a swirl-orifice plate coupling effect. Background Art

[0002] Hydraulic cavitation technology has been widely used in sewage treatment, wastewater degradation, sterilization and disinfection, among which Venturi cavitators are widely recognized for their simple structure, low cost and easy maintenance. The traditional Venturi cavitator has a single structure and insufficient fluid velocity gradient, resulting in low cavitation intensity; and the pressure rises significantly after the cavitation bubble bursts, resulting in poor cavitation continuity. At present, although the multi-stage Venturi, orifice-Venturi coupling structure and vortex-enhanced Venturi tube have improved the cavitation effect to a certain extent, they still have limitations such as complex structure, increased resistance, and unstable cavitation effect, which makes it difficult to fully meet the actual industrial application needs. Therefore, it is necessary to develop a Venturi cavitator with better structure, higher cavitation intensity and better continuity to further improve the application effect and economic benefits of hydraulic cavitation technology. Summary of the invention

[0003] In view of the problems of insufficient cavitation intensity and poor cavitation continuity in the existing Venturi cavitators, the present invention provides a Venturi cavitator based on the swirl-orifice coupling effect, which utilizes the coupling of swirl and central flow to improve the cavitation intensity and form a swirl low-pressure zone in the expansion section to offset the pressure rise caused by cavitation bubble bursting, shorten the cavitation cycle time interval, and effectively enhance the continuity of the cavitation process.

[0004] A venturi cavitator based on swirl-orifice coupling effect comprises a venturi tube body and a hollow spiral guide vane, wherein the venturi tube body comprises an inlet section, a throat and an expansion section in sequence; a spiral guide vane fitted to the inner wall of the venturi tube is arranged inside the inlet section, and a central flow channel is formed at the center of the spiral guide vane; peripheral fluid is guided by the spiral guide vane to generate swirl motion, and enters the throat and the expansion section in a spiral flow state, and the fluid in the central flow channel enters the throat after rectification and concentration, so as to achieve the purpose of improving the fluid velocity gradient and cavitation intensity in the throat area.

[0005] The expansion section structure uses swirling fluid to form a stable low-pressure zone. The diffusion angle α of the expansion section is 1° to 18°, which further induces cavitation development in the expansion section, effectively offsets part of the high-pressure fluctuations generated when the cavitation bursts, shortens the cavitation cycle time interval, and enhances the continuity of the cavitation effect.

[0006] The number of spiral turns of the hollow spiral guide vane can be adjusted according to the equipment size and application requirements, the spiral angle is optimized according to the contraction angle of the Venturi inlet section, the width of the spiral guide vane is set according to the center flow channel size, and is adjusted in combination with the equipment size and fluid working conditions to ensure the best balance between the swirl intensity and the cavitation effect, and improve the system adaptability and cavitation efficiency.

[0007] The pitch of the spiral guide vane can be a constant pitch or a variable pitch, wherein in the case of a variable pitch, the pitch gradually decreases as the inlet section contracts, so as to enhance the swirl acceleration effect and optimize the velocity distribution of the fluid entering the throat.

[0008] The shape of the flow channel cross section can be variable, such as square, triangle, tapered or expanded cylinder, etc., to meet the flow field rectification requirements of different processes.

[0009] The ratio of the center flow channel diameter to the throat diameter is 0.3 to 1. If the center flow channel diameter is too small, the inlet resistance will increase, causing the fluid pressure to be too high before entering the throat, resulting in a large energy loss; if the center flow channel diameter is too large (exceeding the throat diameter), the effect of the spiral fluid will be weakened, causing the swirl to be disturbed by the high-speed axial fluid gathered in the center flow channel before reaching the throat, thereby reducing the cavitation intensity and affecting the overall cavitation effect.

[0010] The working principle of the invention is that after the fluid enters through the inlet section, the peripheral fluid is induced to generate high-speed swirl motion by the spiral guide vane, forming a radial pressure gradient, reducing the pressure in the throat and central area of ​​the expansion section; the central flow channel gathers and rectifies the axial fluid, so that the speed of the central fluid through the throat is accelerated; the coupling effect of radial swirl and axial convergence reduces the local pressure in the throat area and increases the velocity gradient, thereby increasing the number of cavitations generated in the Venturi cavitator, that is, the cavitation intensity; the fluid then enters the expansion section, and the stable low-pressure zone generated by the swirl effectively slows down the pressure recovery after the cavitation burst, shortens the cavitation cycle time interval, and enhances the continuity of the cavitation phenomenon.

[0011] Compared with the traditional Venturi cavitator, the above technical solution provided by the embodiment of the present application has improved cavitation intensity and continuity; compared with the new Venturi cavitator, it has a simple structure and is easy to manufacture and maintain; the velocity gradient of the fluid entering the throat area is increased by the hollow spiral guide vane arranged in the inlet section, and the cavitation intensity is effectively improved by utilizing the swirl-orifice coupling effect; at the same time, a stable low-pressure zone is formed by the swirl fluid in the expansion section, which offsets part of the pressure recovery caused by the cavitation burst, and optimizes the shortcomings of the poor cavitation continuity of the traditional Venturi tube. The present invention further improves the performance of the equipment on the basis of maintaining the structural advantages of the Venturi cavitator, expands its application range in the fields of sewage treatment, sterilization and disinfection, industrial emulsification, oil-water mixing, and agricultural irrigation water treatment, and has broad application prospects and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings herein are incorporated in and constitute a part of the specification, show embodiments of the invention of the Venturi cavitator based on the swirl-orifice plate coupling effect, and together with the description are used to explain the principles of the invention.

[0013] In order to clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 Schematic diagram of the structure of a Venturi cavitator based on the swirl-orifice coupling effect provided in an embodiment of the present application.

[0015] Figure 2 Schematic diagram of the hollow spiral guide vane and central flow channel provided in an embodiment of the present application.

[0016] Figure 3 The following is a summary of the embodiments of the present application.

[0017] 1. Inlet section; 2. Throat; 3. Expansion section; 4. Hollow spiral guide vane; 5. Center flow channel. DETAILED DESCRIPTION

[0018] In order to clearly explain the purpose, technical solution and advantages of the present invention, the embodiments of the present invention are fully described in conjunction with the accompanying drawings. The embodiments are part of the present invention, not all of it. The components in the accompanying drawings may adopt different configurations. The following description is only used to illustrate the selected embodiments, but not to limit the scope of protection of the present invention. Those skilled in the art may adjust or optimize it without creative work, which still falls within the scope of protection of the present invention.

[0019] For ease of understanding, a Venturi cavitator based on the swirl-orifice plate coupling effect provided in the example of this application is described in detail below; Figure 1 and Figure 2 As shown, it includes a venturi tube body and a hollow spiral guide vane, wherein the venturi tube body is sequentially composed of an inlet section 1, a throat 2 and an expansion section 3. A hollow spiral guide vane 4 is arranged inside the inlet section 1, and the spiral guide vane is attached to the inner wall of the venturi tube, and the guide vane is hollow to form a central flow channel 5.

[0020] The cross-sectional shape of the central flow channel 5 can be a square, a triangle, a tapered or expanded cylinder or other shapes to meet the flow field rectification requirements of different processes; a cylindrical shape is preferred in this embodiment.

[0021] The cross-sectional dimensions of the central flow channel 5 are variable. In this embodiment, the ratio of the diameter of the cylindrical cross-sectional area to the diameter of the throat 2 is 1.

[0022] The number of spiral turns of the hollow spiral guide vane 4 is variable and can be adjusted according to the actual equipment size. In this embodiment, 3 turns are preferred. The guide vane pitch can be a constant pitch or a variable pitch. When the pitch is variable, the pitch gradually decreases as the inlet section shrinks to enhance the swirl acceleration effect and optimize the velocity distribution of the fluid entering the throat.

[0023] The inlet section 1 adopts a contraction structure, which is preferably 22.5° in this embodiment; the expansion section 3 is a gradual expansion structure, and the diffusion angle α is 1° to 18°, which is 6° in this embodiment. Both the contraction and expansion angles are adjustable.

[0024] During the working process, the liquid enters the Venturi cavitator through the inlet section, and the peripheral fluid rotates at high speed under the action of the spiral guide vane 4, forming a significant radial pressure gradient, effectively reducing the central pressure in the throat 2 area; at the same time, the fluid in the central flow channel 5 enters the throat 2 at a higher speed after the flow concentration and rectification process, further reducing the pressure in the central area. The radial swirl and axial flow concentration are coupled in the throat, increasing the velocity gradient of the throat fluid, so that the cavitation intensity of the Venturi cavitator is enhanced.

[0025] The mixed fluid enters the expansion section 3, and the swirling fluid continues to form a stable low-pressure area in the expansion section, which delays the rupture time of some cavitation bubbles in the expansion section and effectively offsets the pressure rise caused by the bursting of some cavitation bubbles, shortens the interval of cavitation cycles, improves cavitation continuity, and avoids problems such as poor continuity caused by pressure rise in traditional Venturi tubes.

[0026] Compared with the traditional Venturi cavitator, the embodiment of the present application has significant advantages in structural optimization and performance improvement. The spiral guide vane guides the swirl flow, so that the fluid forms a larger velocity gradient and pressure drop in the throat area, thereby improving the cavitation intensity; the spiral optimization design enables the swirl fluid to form a stable low-pressure area in the expansion section, effectively buffering the pressure rise caused by the cavitation bubble burst and enhancing the continuity of the cavitation process; by optimizing the parameters of the spiral guide vane, the shape of the central flow channel and the expansion section structure, the problems such as poor continuity caused by the pressure rise are reduced, and the stability and service life of the equipment operation are improved; on the basis of maintaining a simple structure, convenient manufacturing and maintenance, the performance of the cavitator is improved, so that it has broad application prospects and social and economic benefits in the fields of sewage treatment, sterilization and disinfection, industrial emulsification and agricultural irrigation water treatment.

Claims

1. A Venturi cavitator based on swirl-orifice coupling effect, characterized in that: include: The venturi tube body comprises an inlet section, a throat, an expansion section and a hollow spiral guide vane; a cylindrical flow channel is formed in the center of the hollow spiral guide vane, and the central flow channel rectifies and converges the fluid before entering the throat, thereby increasing the velocity gradient and cavitation intensity of the fluid in the throat area; the peripheral fluid generates a swirl through the spiral guide vane, enters the throat and extends to the expansion section, and forms a stable low-pressure zone through the swirl effect, which is used to buffer the pressure recovery generated when the cavitation bubble bursts, shorten the cavitation cycle time interval, and improve the cavitation continuity.

2. The Venturi cavitator based on the swirl-orifice coupling effect according to claim 1, characterized in that: The hollow spiral guide plate is arranged on the inner wall of the inlet section of the venturi tube.

3. The Venturi cavitator based on the swirl-orifice coupling effect according to claim 1, characterized in that: The ratio of the center flow channel diameter to the throat diameter is 0.3 to 1. If the center flow channel diameter is too small, the inlet resistance will increase, causing the fluid pressure to be too high before entering the throat, resulting in a large energy loss; if the center flow channel diameter is too large (exceeding the throat diameter), the spiral fluid effect will be weakened, causing the swirl to be disturbed by the high-speed axial fluid gathered in the center flow channel before reaching the throat, reducing the cavitation intensity and affecting the overall cavitation effect.

4. The Venturi cavitator based on swirl-orifice coupling effect according to claim 1, characterized in that: The spiral angle and number of spiral turns of the hollow spiral guide vane are adjustable and can be matched according to the equipment size and fluid working conditions to ensure the optimal balance between the swirl intensity and the cavitation effect; the spiral guide vane pitch can be a constant pitch or a variable pitch, wherein the pitch gradually decreases with the contraction of the inlet section when the pitch is variable to enhance the swirl acceleration effect and optimize the velocity distribution of the fluid entering the throat.

5. The Venturi cavitator based on swirl-orifice coupling effect according to claim 1, characterized in that: The diffusion angle of the expansion section is 1° to 18°, wherein a smaller diffusion angle can enhance the swirl effect, so that the swirl fluid forms a more stable low-pressure zone in the expansion section, so as to effectively reduce the pressure rise caused by cavitation bursting and improve the cavitation continuity; if the diffusion angle is too small, it may lead to insufficient pressure rise and affect the collapse and regeneration of cavitation, while if it is too large, it will weaken the swirl stability and reduce the cavitation intensity. Therefore, the diffusion angle can be optimized and adjusted within this range according to the fluid working conditions to take into account both the swirl enhancement and the cavitation process.

6. The Venturi cavitator based on swirl-orifice coupling effect according to claim 1, characterized in that: The central flow channel is preferably a cylindrical hollow flow channel, and the cross-sectional shape of the flow channel can be variable, such as square, triangle, gradually converging or gradually expanding cylinder, etc., to meet the processing requirements of different fluids and working conditions.

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