Venturi cavitation based on swirl-orifice coupling effect

Abstract

This invention proposes a Venturi cavitation device based on the swirling-orifice coupling effect, relating to the field of fluid cavitation technology. It includes an inlet section, throat, and expansion section of the Venturi tube body, with hollow spiral guide vanes on the inner wall of the inlet section. The spiral guide vanes cause the fluid near the inner wall to rotate at high speed, forming a stable rotation effect and inducing a local low-pressure zone in the expansion section. This effectively counteracts the pressure rise caused by cavitation bursting, shortens the cavitation cycle interval, and enhances the continuity of the cavitation process. The hollow flow channel regulates and accelerates the fluid in the central region, effectively increasing the throat velocity and improving cavitation intensity. This invention has a compact structure, is easy to manufacture, and can simultaneously improve cavitation intensity and continuity. It is widely applicable to various fields such as wastewater degradation, sterilization and disinfection, industrial emulsification, and oil-water mixing treatment, showing good application prospects and economic and social benefits.

Description

Technical Field

[0001] This invention belongs to the technical field of fluid cavitation equipment, specifically relating to a Venturi cavitation device based on the swirling-orifice plate coupling effect. Background Technology

[0002] Hydraulic cavitation technology has been widely applied in wastewater treatment, wastewater degradation, and sterilization. Among these applications, the Venturi cavitation device is widely recognized for its simple structure, low cost, and ease of maintenance. However, traditional Venturi cavitation devices suffer from a simple structure and insufficient fluid velocity gradient, resulting in low cavitation intensity. Furthermore, the significant pressure rebound after cavitation bubble bursts leads to poor cavitation continuity. While multi-stage Venturi, orifice plate-Venturi coupled structures, and vortex-enhanced Venturi tubes have improved cavitation effects to some extent, they still suffer from limitations such as complex structures, increased resistance, and unstable cavitation effects, making it difficult to fully meet the needs of practical industrial applications. Therefore, it is necessary to develop a Venturi cavitation device with a superior 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] To address the problems of insufficient cavitation intensity and poor cavitation continuity in existing Venturi cavitators, this invention provides a Venturi cavitator based on the swirling-orifice coupling effect. It improves cavitation intensity by coupling swirling flow with central convergence and forms a swirling low-pressure zone in the expansion section to counteract the pressure rise generated when cavitation bubbles burst, shorten the cavitation cycle time interval, and effectively enhance the continuity of the cavitation process.

[0004] A Venturi cavitation device based on the swirling-orifice coupling effect includes a Venturi tube body and a hollow spiral guide vane. The Venturi tube body sequentially includes an inlet section, a throat, and an expansion section. The inlet section is provided with a spiral guide vane that fits against the inner wall of the Venturi tube, and a central flow channel is formed at the center of the spiral guide vane. The peripheral fluid is guided by the spiral guide vane to generate swirling motion and enters the throat and expansion section in a spiral flow state. The fluid in the central flow channel enters the throat after rectification and convergence, thereby achieving the purpose of improving the fluid velocity gradient and cavitation intensity in the throat region.

[0005] The expansion section structure utilizes 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 within the expansion section, effectively offsetting some of the high-pressure fluctuations generated when cavitation bursts, shortening the cavitation cycle time interval, and enhancing 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 by matching the contraction angle of the Venturi inlet section. The width of the spiral guide vane is set according to the size of the central flow channel and adjusted in combination with the equipment size and fluid conditions to ensure the best balance between swirling intensity and cavitation effect, thereby improving system adaptability and cavitation efficiency.

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

[0008] The cross-sectional shape of the flow channel can be varied, such as square, triangle, tapered or expanding cylinder, to meet the flow field rectification requirements of different processes.

[0009] The ratio of the central flow channel diameter to the throat diameter is 0.3 to 1. If the central 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 central flow channel diameter is too large (exceeding the throat diameter), the effect of the spiral fluid will be weakened, and the swirling flow will be disturbed by the high-speed axial fluid converging in the central flow channel before reaching the throat, thereby reducing the cavitation intensity and affecting the overall cavitation effect.

[0010] The invention works by the following principle: after the fluid enters through the inlet section, the peripheral fluid is induced to generate high-speed swirling motion by the spiral guide vanes, forming a radial pressure gradient and reducing the pressure in the throat and the central region of the expansion section; the central flow channel converges and rectifyes the axial fluid, making the central fluid pass through the throat faster; the coupling effect of radial swirling and axial convergence reduces the local pressure in the throat region and increases the velocity gradient, thereby increasing the number of cavitation bubbles generated by the Venturi cavitation cavitation duct, i.e., the cavitation intensity; the fluid then enters the expansion section, where the stable low-pressure zone generated by the swirling effectively slows down the pressure rise after the cavitation bubbles burst, shortens the cavitation cycle time interval, and enhances the continuity of the cavitation phenomenon.

[0011] Compared with traditional Venturi cavitation devices, the technical solutions provided in this application improve both cavitation intensity and continuity. Compared with new-type Venturi cavitation devices, they have a simpler structure and are easier to manufacture and maintain. The hollow spiral guide vanes in the inlet section increase the velocity gradient of the fluid entering the throat region, effectively enhancing cavitation intensity through the swirling-orifice coupling effect. Simultaneously, the swirling fluid in the expansion section forms a stable low-pressure zone, offsetting some of the pressure rise caused by cavitation bursting, thus optimizing the poor cavitation continuity of traditional Venturi tubes. This invention further improves equipment performance while maintaining the structural advantages of Venturi cavitation devices, expanding its application scope in wastewater treatment, sterilization, industrial emulsification, oil-water mixing, and agricultural irrigation water treatment, demonstrating broad application prospects and economic benefits. Attached Figure Description

[0012] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the Venturi cavitation condenser invention based on the swirling-orifice coupling effect and, together with the description, serve to explain the principles of the invention.

[0013] To clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 A schematic diagram of a Venturi cavitation device structure based on the swirl-orifice plate coupling effect provided in an embodiment of this application.

[0015] Figure 2 A schematic diagram of the hollow spiral guide vane and central flow channel provided in the embodiments of this application.

[0016] Figure 3 The accompanying drawings are abstracts of embodiments provided in this application.

[0017] 1. Inlet section; 2. Throat; 3. Expansion section; 4. Hollow spiral guide vane; 5. Central flow channel. Detailed Implementation

[0018] To clearly illustrate the objectives, technical solutions, and advantages of this invention, the embodiments of the invention are described in full with reference to the accompanying drawings. These embodiments are part, but not all, of this invention. Components in the drawings may be configured differently. The following description is only for illustrating selected embodiments and is not intended to limit the scope of protection of this invention. Adjustments or optimizations made by those skilled in the art without inventive effort still fall within the scope of protection of this invention.

[0019] For ease of understanding, the following provides a detailed description of a Venturi cavitation device based on the swirl-orifice plate coupling effect provided in this application; such as... Figure 1 and Figure 2 As shown, the device includes a venturi tube body and a hollow spiral guide vane. The venturi tube body is composed of an inlet section 1, a throat 2, and an expansion section 3. A hollow spiral guide vane 4 is disposed inside the inlet section 1. The spiral guide vane is attached to the inner wall of the venturi tube, and the hollow guide vane forms 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 expanding cylinder, or other shapes, to meet the flow field rectification requirements of different processes; in this embodiment, a cylindrical shape is preferred.

[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-section to the diameter of the throat 2 is 1.

[0022] The hollow spiral guide vane 4 has a variable number of spiral turns, which can be adjusted according to the actual equipment size. In this embodiment, it is preferably 3 turns. The pitch of the guide vane can be a constant pitch or a variable pitch. When the pitch is variable, the pitch gradually decreases as the inlet section contracts, so as to enhance the swirling 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 has a gradually expanding structure with a diffusion angle α of 1° to 18°, which is 6° in this embodiment. Both the contraction and expansion angles are adjustable.

[0024] During operation, liquid enters the Venturi cavitator through the inlet section. The peripheral fluid rotates at high speed under the action of the spiral guide vanes 4, forming a significant radial pressure gradient, effectively reducing the central pressure in the throat region 2. Simultaneously, the fluid in the central flow channel 5, after being converged and rectified, enters the throat 2 at an even higher velocity, further reducing the pressure in the central region. The radial swirling flow and axial convergence couple at the throat, increasing the fluid velocity gradient and enhancing the cavitation intensity of the Venturi cavitator.

[0025] The mixed fluid enters the expansion section 3, where the swirling fluid continues to form a stable low-pressure region. This delays the cavitation bursting time in the expansion section and effectively counteracts the pressure rise caused by the bursting of some cavitation bubbles, shortening the cavitation cycle interval, improving cavitation continuity, and avoiding problems such as poor continuity caused by pressure rise in traditional Venturi tubes.

[0026] Compared to traditional Venturi cavitators, the embodiments described in this application have significant advantages in terms of structural optimization and performance improvement. By guiding the swirling flow with helical guide vanes, a larger velocity gradient and pressure drop are formed in the throat region, enhancing cavitation intensity. The optimized helical design creates a stable low-pressure zone in the expansion section, effectively buffering the pressure rise caused by cavitation bubble bursts and enhancing the continuity of the cavitation process. Optimizing the parameters of the helical guide vanes, the morphology of the central flow channel, and the structure of the expansion section reduces problems such as poor continuity due to pressure rise, improving the stability and service life of the equipment. While maintaining a simple structure and convenient manufacturing and maintenance, the improved cavitation performance makes it widely applicable in wastewater treatment, sterilization and disinfection, industrial emulsification, and agricultural irrigation water treatment, offering significant socio-economic benefits.

Claims

1. A Venturi cavitation device based on the swirl-orifice plate coupling effect, characterized in that, The device includes a venturi tube body and a hollow spiral guide vane. The venturi tube body includes an inlet section, a throat, and an expansion section in sequence along the fluid flow direction. The hollow spiral guide vane is fitted to the inner wall of the inlet section, and a cylindrical central flow channel is formed at its center. The ratio of the diameter of the cylindrical central flow channel to the diameter of the throat is 0.3 to 1. The diffusion angle of the expansion section is 1° to 18°. The peripheral fluid forms a swirling flow through the hollow spiral guide vane and enters the throat and expansion section. The central fluid is rectified and converged through the cylindrical central flow channel before entering the throat, thereby increasing the velocity gradient and cavitation intensity of the fluid in the throat region. The swirling effect forms a stable low-pressure zone in the expansion section to buffer the pressure rise generated when cavitation bubbles burst, shorten the cavitation cycle time interval, and improve cavitation continuity.

2. The Venturi cavitation device based on the swirl-orifice plate 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; the pitch of the hollow spiral guide vane is either a constant pitch or a variable pitch, wherein when the pitch is variable, the pitch gradually decreases along the contraction direction of the inlet section.

3. The Venturi cavitation device based on the swirl-orifice plate coupling effect according to claim 1, characterized in that, The hollow spiral guide vane has a cylindrical central flow channel that gradually narrows along the direction of fluid flow.

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