Coanda effect-based focused water jet injection enhancing device

Abstract

The invention provides a focused water jet injection enhancing device based on the coanda effect. Comprising an enhanced ejector, a main pump, an auxiliary pump, a main pump diverter valve, an auxiliary pump diverter valve, a five-way valve and a water tank. The main pump provides high-pressure water flow to drive the enhanced ejector to generate high-speed water flow, the auxiliary pump provides low-speed water flow and distributes the low-speed water flow to the enhanced ejector through the five-way valve, contact between the high-speed water flow and the inner wall of the nozzle is reduced, and the influence of a boundary layer is eliminated. The enhanced ejector comprises a water inlet connecting pipe, a flow stabilizer and a Coanda flow guide nozzle, the flow stabilizer guides water flow through an axial flow guide rib plate, and vortex and flow instability are reduced; the coanda flow guide nozzle guides water flow to stably flow along the inner wall of the nozzle through the coanda effect, the jet divergence angle is reduced, and the jet concentration ratio and the energy density are enhanced. The inner flow channel of the enhanced ejector is combined with the cycloid flow guide area, the straight column flow guide area and the contraction flow guide area, and by optimizing the dynamic behavior of water flow, vortex and instability are reduced, and the stability and impact force of jet flow are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of mechanical engineering, such as water jet cleaning, water jet cutting, water jet propulsion, etc., and in particular to a focused water jet spray enhancement device based on the Coanda effect. BACKGROUND

[0002] In the field of water jet cleaning, water jet cutting, etc., the energy density requirement of water jet is getting higher and higher, that is, water jet must have higher concentration and stronger long-distance impact force to achieve more efficient and more accurate work. However, in the traditional water jet application, a relatively simple nozzle design is usually adopted, which is difficult to effectively control the focusing of the water flow, resulting in a large divergence angle of the spray flow, rapid energy diffusion, and rapid weakening of the impact force. This is mainly due to the defects of the nozzle design in fluid dynamics, energy transmission, and spray stability, thereby restricting its performance and application range. The main defects in the prior art are as follows:

[0003] (1) The divergence angle of the spray flow is too large, and the jet concentration is poor

[0004] The traditional spray device, especially the conventional nozzle design, usually relies on a circular or simplified flow channel shape. Such design cannot effectively limit the divergence angle of the spray flow during fluid flow, resulting in uneven energy distribution of the jet. The large divergence angle of the jet will cause the energy to rapidly diffuse during the spraying process, thereby reducing the spraying effect. In applications that require precise control of the spraying position and direction, the large divergence angle will cause the jet to be unable to concentrate in the target area, affecting the working efficiency and cleaning and cutting accuracy of the system. Especially in complex surface cleaning or precision cutting applications with high requirements, the concentration and precision of the jet directly affect the completion quality of the task.

[0005] (2) The spray speed decays rapidly, and the long-distance spray effect is poor

[0006] In the existing jet device, the spray pressure is usually achieved through the traditional nozzle geometry and flow regulation. However, this design method causes the kinetic energy and impact force of the fluid to decay exponentially during the spraying process due to the increase in spraying distance, resulting in a significant decrease in spraying effect, especially in long-distance spraying, the cliff-like decline in spraying effect is more obvious. The existing technology cannot effectively optimize the balance between the spraying pressure and the decay of the spraying speed without increasing energy consumption, resulting in low device efficiency and difficulty in meeting the industrial demand for long-distance spraying.

[0007] (3) Instability and non-uniformity of the jet fluid

[0008] The current jet device common jet fluid instability problem from the flow channel design inaccuracy, nozzle shape irregularity and the phenomenon of bubble, vortex flow generated in the process of jet. In high pressure water jet, the stability of the fluid is very important, especially in the cleaning and cutting process, the fluid inhomogeneity will lead to the fluctuation of cleaning effect, even appear local unable to effectively remove impurities. Flow instability and vortex flow will not only make the jet intensity and direction deviation, but also may cause damage to the target surface, reduce the working precision and reliability of the jet device.

[0009] (4) Fluid and nozzle interface interaction problem

[0010] The interaction between the nozzle and fluid flow in the jet device, especially in the high-speed water jet system, the friction between the fluid and the inner surface of the nozzle, the formation of bubbles and the fluid adhesion force often lead to the obstacle of fluid motion. These phenomena may exacerbate the wear and corrosion of the nozzle during long-term operation, affecting the long-term stability and reliability of the jet device. In addition, due to the friction between the fluid and the inner surface of the nozzle and the inhomogeneity of the flow, it may lead to the reduction of jet efficiency and energy waste. SUMMARY

[0011] The technical problem to be solved by the present application is to provide a focused water jet jet enhancement device based on the Coanda effect, which solves the above-mentioned defects in the prior art. Through the guiding effect of the Coanda effect, the flow trajectory of high-speed water flow is optimized, the divergence angle of the fluid during the jet process is kept smaller, and the concentration and energy density of the jet are significantly improved. At the same time, by using the physical effect of the boundary layer formed by the fluid on the inner surface of the nozzle, low-speed water flow is introduced when high-speed jet is about to leave the nozzle, reducing the direct contact between high-speed fluid and the inner wall of the nozzle, and promoting the separation of the boundary layer. This design effectively reduces the flow resistance and improves the stability and impact force of the water jet. The device not only can improve the precision of the jet, but also can significantly reduce the energy loss and improve the overall performance of the equipment, thereby solving the problems of large jet divergence angle, energy waste and rapid decay of long-distance impact force in the traditional technology.

[0012] The application provides a focusing water jet injection enhancement device based on the Coanda effect, which comprises an enhanced injector, a main pump, a main pump shunt valve, an auxiliary pump, an auxiliary pump shunt valve, a five-way valve and a water tank; the main pump is connected with the inlet end of the enhanced injector, the main pump is connected with the water tank through the main pump shunt valve, the auxiliary pump is connected with the inlet end of the five-way valve, the auxiliary pump is connected with the water tank through the auxiliary pump shunt valve, and the outlet end of the five-way valve is connected with the outlet end of the enhanced injector. The main pump provides high-pressure and high-speed water flow for the enhanced injector. The main pump shunt valve is used for adjusting the output flow of the main pump, ensuring that the stable high-pressure water flow flows into the enhanced injector, so that the flow and injection intensity in the enhanced injector are maintained. The auxiliary pump provides high-pressure and low-speed water flow, and the auxiliary pump shunt valve is used for adjusting the flow of the low-speed water flow. The low-speed water flow is mixed with the main flow at the outlet end of the enhanced injector, and the jet effect is optimized through precise design. The five-way valve is connected with the auxiliary pump, and the main function is to uniformly distribute the low-speed water flow from the auxiliary pump into four parts and send them into different parts of the enhanced injector. Through this shunt mechanism, the low-speed water flow can form a buffer layer inside the enhanced injector, reduce the direct contact of the high-speed water flow with the inner wall of the nozzle of the enhanced injector, and effectively eliminate the influence of the boundary layer. The water tank provides sufficient water source, ensuring the continuous water supply and stable operation of the system.

[0013] Preferably, the enhanced injector comprises a water inlet pipe, a flow stabilizer and a Coanda guide nozzle; the inlet end of the enhanced injector is provided with the water inlet pipe, the outlet end of the enhanced injector is provided with the Coanda guide nozzle, and the flow stabilizer is arranged between the water inlet pipe and the Coanda guide nozzle; one end of the water inlet pipe opposite to the flow stabilizer is connected with the main pump, and the Coanda guide nozzle is connected with the outlet end of the five-way valve. The water inlet pipe is connected with the main pump, ensuring that the system stably receives water flow and smoothly introduces it. The flow stabilizer is arranged between the water inlet pipe and the Coanda guide nozzle, is responsible for dividing the water flow, eliminating vortex and reducing flow instability, the Coanda guide nozzle utilizes the Coanda effect to guide the water flow to flow smoothly along the inner wall of the nozzle, reduces the jet divergence angle, enhances the concentration and energy density of the jet, and can introduce high-pressure and low-speed water flow, reduces the direct contact of the high-speed water flow with the inner wall of the nozzle, and effectively eliminates the influence of the boundary layer. These components are connected through thread screwing, and are provided with sealing rings to ensure the sealing property of the system.

[0014] Preferably, the flow stabilizer has a plurality of axial guide ribs, and the head and tail of the guide rib are in arc-shaped structures, which can effectively inhibit the vortex generated by the high-speed water flow at the interface mutation.

[0015] Preferably, the conical nozzle is sequentially arranged along the direction from the inlet end of the enhanced injector to the outlet end of the enhanced injector: a first trochoidal flow guide region, a first straight column flow guide region, a first converging flow guide region, a second straight column flow guide region, a second trochoidal flow guide region, a third straight column flow guide region, a second converging flow guide region, a nozzle outlet straight column section, and a high-pressure low-speed water flow inlet section. Specifically, the high-pressure low-speed water flow inlet section is composed of four channels, which are inclined along the jetting direction of the high-speed water flow to optimize the flow coordination between the low-speed water flow and the high-speed water flow. Each flow guide region optimizes the dynamic characteristics of the water flow through multi-stage flow guidance, ensuring smooth flow of the fluid in the conical nozzle and forming a highly concentrated jet at the nozzle outlet.

[0016] The application also provides a parameter setting of a focused water jet injection enhancement device based on the Coanda effect, which includes the proportional relationship between the main pump pressure P z and the auxiliary pump pressure P f , the proportional relationship between the main pump flow Q Z and the auxiliary pump flow Q f , and the proportional relationship between multiple key parameters with the nozzle outlet straight column section outlet diameter D as the size reference, specifically including: the trochoidal generating circle diameter A1 of the first trochoidal flow guide region, the trochoidal generating circle diameter A2 of the second trochoidal flow guide region, the diameter D1 of the first straight column flow guide region , the diameter D2 of the second straight column flow guide region , the diameter D3 of the third straight column flow guide region , the diameter D4 of the high-pressure low-speed water flow inlet section , the water inlet connector passage diameter D5 , and the flow stabilizer passage diameter D6 In addition, the method also gives the contraction angle β of the first converging flow guide region and the second converging flow guide region, and the inclination angle δ of the high-pressure low-speed water flow inlet section and the nozzle axis. The setting and control of these parameters help to optimize the flow trajectory and jetting effect of the fluid, ensuring smooth transition of the high-pressure water flow and the low-speed water flow, thereby improving the stability, concentration, and energy density of the water jet.

[0017] The beneficial effects of the application at least include:

[0018] (1) Improving jet concentration and energy density: optimizing the flow trajectory of the jetting fluid through the Coanda effect, enhancing the concentration and impact force of the jet.

[0019] (2) Improving jetting accuracy and stability: eliminating part of the boundary layer of the high-speed water flow by introducing low-speed water flow, improving the stability and accuracy of the water jet.

[0020] (3) Reducing energy loss and improving work efficiency: optimizing water flow kinetic energy transmission, reducing energy waste, and improving equipment efficiency.

[0021] (4) Flexible flow and pressure adjustment: By precisely controlling the proportional relationship between the main pump and the auxiliary pump, flexible flow and pressure adjustment is achieved to meet different application requirements. BRIEF DESCRIPTION OF DRAWINGS

[0022] A more complete understanding of the present application and the attendant advantages and features thereof will be more fully understood by considering the following detailed description in conjunction with the accompanying drawings, in which:

[0023] Figure 1 The overall structure schematic diagram of the focusing water jet spray enhancement device based on the Coanda effect according to the preferred embodiment of the present application is schematically shown.

[0024] Figure 2 The structure schematic diagram of the water inlet pipe is schematically shown.

[0025] Figure 3 The structure schematic diagram of the flow stabilizer is schematically shown.

[0026] Figure 4 The structure schematic diagram of the axial flow guide rib plate is schematically shown.

[0027] Figure 5 The structure schematic diagram of the Coanda flow guide nozzle is schematically shown.

[0028] Figure 6 The size parameter schematic diagram of the Coanda flow guide nozzle is schematically shown.

[0029] BRIEF DESCRIPTION OF DRAWINGS

[0030] Enhanced sprayer 1; main pump 2; main pump shunt valve 3; auxiliary pump 4; auxiliary pump shunt valve 5; five-way valve 6; water tank 7; water inlet pipe 1-1; flow stabilizer 1-2; Coanda flow guide nozzle 1-3; flow guide rib plate 1-2-1; flow guide rib plate tail structure 1-2-2; flow guide rib plate head structure 1-2-3; first cycloid flow guide area 1-3-1; first straight column flow guide area 1-3-2; first contraction flow guide area 1-3-3; second straight column flow guide area 1-3-4; second cycloid flow guide area 1-3-5; third straight column flow guide area 1-3-6; second contraction flow guide area 1-3-7; nozzle outlet straight column section 1-3-8; high-pressure low-speed water flow inlet section 1-3-9; first cycloid flow guide area cycloid generating circle diameter A1; second cycloid flow guide area cycloid generating circle diameter A2; first straight column flow guide area diameter Second straight column flow guide area diameter Third straight column flow guide area diameter High-pressure low-speed water flow inlet section diameter Water inlet pipe diameter Flow stabilizer diameter The first contraction flow area and the second contraction flow area have a contraction angle β; the high-pressure low-speed water flow inlet section and the nozzle axis have an inclination angle δ.

[0031] It should be noted that the drawings are used to illustrate the present application, not to limit the present application. Note that the drawings showing the structure may not be drawn to scale. And in the drawings, the same or similar elements are marked with the same or similar reference numerals. DETAILED DESCRIPTION

[0032] In order to make the content of the present application more clear and easy to understand, the content of the present application is described in detail below in combination with specific embodiments and drawings.

[0033] As Figures 1-6 shown, the present application provides a focused water jet enhanced spraying device based on the Coanda effect, comprising: an enhanced sprayer 1, a main pump 2, a main pump shunt valve 3, an auxiliary pump 4, an auxiliary pump shunt valve 5, a five-way valve 6, a water tank 7. The main pump 2 is connected with the inlet end of the enhanced sprayer 1, and the main pump 2 is connected with the water tank 7 through the main pump shunt valve 3; the auxiliary pump 4 is connected with the inlet end of the five-way valve 6, and the auxiliary pump 4 is connected with the water tank 7 through the auxiliary pump shunt valve 5; the outlet end of the five-way valve 6 is connected with the outlet end of the enhanced sprayer 1. When working, the main pump 2 provides high-pressure high-speed water flow for the enhanced sprayer 1. The main pump shunt valve 3 is used to adjust the output flow of the main pump 2, to ensure that the stable high-pressure high-speed water flow flows into the enhanced sprayer 1, thereby maintaining the water flow and spraying intensity in the enhanced sprayer 1. The auxiliary pump 4 provides high-pressure low-speed water flow, and the auxiliary pump shunt valve 5 is used to adjust the flow of the high-pressure low-speed water flow. These low-speed water flows are mixed with the main flow at the outlet end of the enhanced sprayer 1, and the jet effect is optimized through precise design. The five-way valve 6 is connected with the auxiliary pump 4, and the main function is to evenly distribute the low-speed water flow from the auxiliary pump 4 into 4 parts, and send them into different parts of the enhanced sprayer 1 respectively. Through this shunt mechanism, the low-speed water flow can form a buffer layer inside the enhanced sprayer 1, reducing the direct contact of high-speed water flow with the inner wall of the nozzle, effectively eliminating the influence of the boundary layer. The water tank 7 provides sufficient water source to ensure the continuous water supply and stable operation of the system.

[0034] The enhanced injector 1 comprises a water inlet pipe 1-1, a flow stabilizer 1-2, and a Coanda guide nozzle 1-3. The water inlet pipe 1-1 is located at the inlet end of the enhanced injector 1 and is connected to the main pump 2 to ensure stable water flow and smooth introduction. The flow stabilizer 1-2 is arranged between the water inlet pipe 1-1 and the Coanda guide nozzle 1-3, responsible for dividing the water flow, eliminating vortex, and reducing flow instability. The Coanda guide nozzle 1-3 is located at the outlet end of the enhanced injector 1, which uses the Coanda effect to guide the water flow along the inner wall of the nozzle, reducing the jet divergence angle, enhancing the concentration and energy density of the jet, and introducing high-pressure low-speed water flow to reduce the direct contact between high-speed water flow and the inner wall of the nozzle, effectively eliminating the influence of the boundary layer. These components are connected by screwing and are equipped with sealing rings to ensure the sealing of the system.

[0035] The flow stabilizer 1-2 is internally designed with an axial guide rib plate 1-2-1, which is arranged along the axis of the water flow and plays an important role in flow guiding. Through the structural design of the axial guide rib plate 1-2-1, the water flow is effectively guided when flowing through the flow stabilizer 1-2, and the axial guide rib plate 1-2-1 helps to evenly distribute the fluid and reduces the vortex and unstable flow that may occur during flow. The presence of the axial guide rib plate 1-2-1 enhances the axial component of the water flow and reduces the generation of vortex by guiding the direction of the water flow, ensuring that the fluid remains stable before entering the Coanda guide nozzle 1-3. At the same time, the axial guide rib plate 1-2-1 is designed as an arc at the tail 1-2-2 and the head 1-2-3, which can guide the fluid to smoothly transition to the Coanda guide nozzle 1-3, ensuring that the water flow can be smoothly guided when flowing on its surface, eliminating the disturbance of the fluid due to uneven flow velocity.

[0036] The first trochoidal flow guide area 1-3-1, the first straight column flow guide area 1-3-2, the first contraction flow guide area 1-3-3, the second straight column flow guide area 1-3-4, the second trochoidal flow guide area 1-3-5, the third straight column flow guide area 1-3-6, the second contraction flow guide area 1-3-7, the nozzle outlet straight column section 1-3-8, and the high-pressure low-speed water flow inlet section 1-3-9 are sequentially arranged along the enhanced injector inlet end to the enhanced injector outlet end direction of the Coanda flow guide nozzle 1-3. Specifically, the high-pressure low-speed water flow inlet section 1-3-9 is composed of four passages, which are uniformly distributed around the nozzle outlet straight column section 1-3-8, and the four passages are inclined along the jet direction of the high-speed water flow to optimize the flow coordination of the low-speed water flow and the high-speed water flow. The Coanda flow guide nozzle 1-3 utilizes the Coanda effect to guide the water flow to flow smoothly along the inner wall of the Coanda flow guide nozzle 1-3. When the water flow gradually contacts the first trochoidal flow guide area 1-3-1, the first straight column flow guide area 1-3-2, the first contraction flow guide area 1-3-3, the second straight column flow guide area 1-3-4, the second trochoidal flow guide area 1-3-5, the third straight column flow guide area 1-3-6, and the second contraction flow guide area 1-3-7, the water flow tends to adhere to and flow along the surface due to the inertial effect, thereby forming a smooth flow path. In the Coanda flow guide nozzle 1-3, the internal flow channel combines the structure and layout of the trochoidal flow guide area (including the first trochoidal flow guide area 1-3-1 and the second trochoidal flow guide area 1-3-5), the straight column flow guide area (including the first straight column flow guide area 1-3-2, the second straight column flow guide area 1-3-4, and the third straight column flow guide area 1-3-6), and the contraction flow guide area (including the first contraction flow guide area 1-3-3 and the second contraction flow guide area 1-3-7) to optimize the kinetic behavior of the water flow. The trochoidal flow guide area fully utilizes the progressive and adaptive nature of the trochoidal curve through its unique geometric characteristics. When the water flow flows along the curve, the inertia of the fluid can be utilized to guide the fluid to flow smoothly along the surface, thereby reducing the vortex effect and instability of the fluid. This characteristic of the trochoid makes the flow of the fluid within the Coanda flow guide nozzle 1-3 more concentrated, and as the fluid flows along the curve, the change in its flow velocity is relatively smooth, avoiding energy loss caused by sharp turns. This continuous flow path reduces the lateral disturbance of the fluid and reduces the energy loss, thereby improving the concentration and energy density of the jet. The straight column flow guide area further ensures that the flow of the fluid within the Coanda flow guide nozzle 1-3 remains stable by providing a stable straight flow channel, and irregular design does not cause flow velocity fluctuations or eddy currents, ensuring accurate control and jetting effect of the water flow. The contraction flow guide area accelerates the speed of the fluid by contracting the cross-section of the flow channel of the Coanda flow guide nozzle 1-3. According to the principles of fluid mechanics, the fluid will accelerate in the contraction flow channel, satisfying the continuity equation and Bernoulli equation. At the same time, the Coanda flow guide nozzle 1-3 can introduce high-pressure low-speed water flow through the four high-pressure low-speed water flow inlet sections 1-3-9, reducing the direct contact of the high-speed water flow with the nozzle outlet straight column section 1-3-8.By designing four fluid channels, the low-speed water flow forms a buffer zone in the Coanda guide nozzle 1-3, reducing the friction between the high-pressure high-speed water flow and the wall surface of the straight column section 1-3-8 of the Coanda guide nozzle 1-3 outlet, and reducing the formation of the boundary layer. The boundary layer is a low-speed area formed due to the gradual decrease of flow velocity when fluid flows on the surface of a solid, which usually affects the stability and speed of the fluid. The introduction of high-pressure low-speed water flow separates the "boundary layer" and eliminates the direct contact between the high-pressure high-speed water flow and the wall surface of the straight column section 1-3-8 of the Coanda guide nozzle 1-3 outlet, thereby avoiding the frictional resistance caused by the boundary layer, further improving the focusing, stability, speed and impact force of the jet.

[0037] In summary, the beneficial effects of the present application include at least:

[0038] 1) Improve jet concentration and energy density: optimize the flow trajectory of the jet fluid through the Coanda effect, enhance the concentration and impact force of the jet.

[0039] (2) Improve jet accuracy and stability: eliminate part of the boundary layer of high-speed water flow by introducing low-speed water flow, improve the stability and accuracy of water jet.

[0040] (3) Reduce energy loss and improve work efficiency: optimize water flow energy transfer, reduce energy waste and improve equipment efficiency.

[0041] (4) Flexible flow and pressure adjustment: accurately control the proportional relationship between the main pump and the auxiliary pump to achieve flexible flow and pressure adjustment to meet different application requirements.

[0042] Now referring to the accompanying drawings, the parameter settings of the above-mentioned focused water jet based on the Coanda effect of the preferred embodiment of the present application are described as follows.

[0043] The proportional relationship between the main pump pressure P z and the auxiliary pump pressure P f :

[0044] 0.92p f ≤ P z ≤ 0.98p f

[0045] This proportional relationship, derived from extensive experimental testing, describes a strict proportional constraint between the pressure of the main pump 2 and the auxiliary pump 4, ensuring their dynamic synergy during operation. The main pump 2 provides a high-pressure, high-velocity water flow to drive the enhanced injector 1, generating sufficient jet energy. The auxiliary pump 4 provides a high-pressure, low-velocity water flow, primarily reducing direct contact between the high-pressure, high-velocity water flow and the straight section 1-3-8 at the nozzle outlet, thereby eliminating the boundary layer, stabilizing fluid flow, and optimizing jet performance. This proportional relationship is based on the principle of energy optimization in fluid mechanics. A reasonable pressure difference ensures synergy between the two pumps, avoiding system failure or energy loss due to pressure mismatch. If the pressure of the main pump 2 is too high, unnecessary energy waste may occur, leading to fluid dynamic instability and affecting jet accuracy. Conversely, if the pressure of the main pump 2 is too low, it may fail to provide sufficient impact force, resulting in unsatisfactory jet performance. By strictly controlling the pressure ratio between the main pump 2 and the auxiliary pump 4, mutual matching between them during operation can be ensured, thereby reducing pressure fluctuations, optimizing energy transfer, improving jet stability, and achieving efficient and stable fluid dynamic performance.

[0046] Main pump flow rate Q Z With auxiliary pump flow rate Q f The proportional relationship between them:

[0047] 12Q f ≤Q z ≤15Q f

[0048] This ratio was derived from extensive experimental testing. The displacement of the main pump 2 is 12 to 15 times larger than that of the auxiliary pump 4. This is primarily because the main pump 2 is responsible for providing the high-pressure, high-speed water flow required by the system, while the auxiliary pump 4 provides a high-pressure, low-speed water flow to eliminate the boundary layer and ensure the stability of the jet fluid. Generating a high-pressure, high-speed water flow requires a large displacement to meet the high energy density and concentration requirements of the jetting device, while ensuring sufficient impact force and jetting accuracy. Since the main function of the main pump 2 is to maintain the high-pressure, high-speed fluid flow in the system, while the auxiliary pump 4's role is limited to providing a low-speed water flow to reduce the contact between the high-pressure, high-speed water flow and the nozzle's inner wall, the displacement of the main pump 2 must be much larger than that of the auxiliary pump 4 to ensure the stability and efficiency of the water jet. By optimizing the displacement ratio of the main pump 2 and the auxiliary pump 4, the needs of high-pressure, high-speed fluid and high-pressure, low-speed fluid can be balanced at different operational stages.

[0049] The nozzle outlet straight column section outlet diameter Using dimensional references, the diameters of the cycloidal generating circles in the first cycloidal guide region (A1), the second cycloidal guide region (A2), and the first cylindrical guide region (diameter) are defined as follows: Diameter of the second straight column drainage area Third straight column drainage area diameter High pressure low speed water flow inlet section diameter Water inlet pipe passage diameter Steady flow device passage diameter The proportional relationship is:

[0050] A1 = 1.56 φD0

[0051] A2 = 0.94 φD0

[0052] φD1 = 4.0 φD0

[0053] φD2 = 3.2 φD0

[0054] φD3 = 1.3 φD0

[0055]

[0056] φD j = φD k = (7 ~ 8) φD0

[0057] The proportional relationship is obtained according to a large number of numerical calculations and experimental tests. In the application, the geometric structure design of the Coanda guide nozzle 1-3 optimizes the flow characteristics of the water flow by precisely controlling the diameter ratio of each part, and comprehensively improves the performance of the jet device from the perspective of fluid mechanics, Coanda effect and boundary layer theory. In the framework of fluid dynamics, the different regions of the Coanda guide nozzle 1-3 adjust the velocity distribution and pressure gradient of the water flow through appropriate size ratios, so as to realize the smooth transition of the water flow. Specifically, the design of the contraction guide area (including the first contraction guide area 1-3-3 and the second contraction guide area 1-3-7) is based on the continuity equation and Bernoulli equation. When the fluid passes through the contraction guide area, the velocity of the fluid will accelerate with the contraction of the flow passage. This design ensures that the fluid has enough kinetic energy at the nozzle outlet straight column section 1-3-8 to meet the requirements of high-precision jetting and high-impact force. The Coanda effect guides the fluid to flow smoothly along the surface of the nozzle inner wall through the curvature of the nozzle inner wall. When the water flow contacts the cycloid guide area (including the first cycloid guide area 1-3-1 and the second cycloid guide area 1-3-5), the fluid adheres to the surface due to the inertial effect, greatly reduces the divergence angle of the fluid, and reduces the energy loss caused by unstable flow, ensuring the high concentration and stability of the water jet. Mathematically, this effect can be described by the Navier-Stokes equation. The momentum transfer and velocity gradient of the fluid when contacting the curved surface determine the stability and impact force of the fluid. In addition, in order to further optimize the jet performance, the high-pressure low-speed water flow inlet section 1-3-9 is introduced in the design. By forming a buffer flow area inside the nozzle outlet straight column section 1-3-8, the contact between high-speed water flow and the inner wall of the nozzle outlet straight column section 1-3-8 is effectively reduced, and the formation of the boundary layer is inhibited. The boundary layer theory shows that the flow velocity of the fluid near the solid surface gradually decreases. If the thickness is not effectively managed, it will lead to unstable flow and energy loss. Therefore, by precisely controlling the design of the high-pressure low-speed water flow inlet section 1-3-9, the kinetic behavior of the water flow inside the nozzle outlet straight column section 1-3-8 is optimized, the influence of the boundary layer is minimized, and finally the stability, speed and impact force of the jet are improved.

[0058] The design values of the first contraction guide area and the second contraction guide area contraction angle β, and the high-pressure low-speed water flow inlet section and the nozzle axis inclination angle δ are:

[0059] β = 12° ~ 13°

[0060] δ = 30° ~ 40°

[0061] The two angle settings, including the contraction angle β of the first and second contraction flow guide zones and the inclination angle δ of the high-pressure low-speed water flow inlet section and the nozzle axis, are determined according to the principles of fluid dynamics and the requirements of nozzle design. A too large contraction angle β will result in too sharp fluid flow, generating greater flow instability and vortex, thereby affecting the jetting effect; while a too small contraction angle will result in insufficient fluid acceleration, and the energy of the jetted fluid cannot be fully concentrated. Therefore, an angle design of 12° to 13° can effectively balance the fluid acceleration and stability. As for the inclination angle δ, the inlet section of the high-pressure low-speed water flow needs to maintain an appropriate angle with the nozzle axis, so as to guide the low-speed fluid to smoothly enter the nozzle, avoiding the formation of backflow or vortex, and a design of 30° to 40° can ensure the smooth transition of the fluid and reduce the interference to the jetted fluid.

[0062] The parametric equation of the cycloid of the first cycloid flow guide zone 1-3-1 is:

[0063] where θ = π

[0064] The parametric equation of the cycloid of the second cycloid flow guide zone 1-3-5 is:

[0065] where θ = π

[0066] It can be understood that although the present application has been disclosed as above with preferred embodiments, the above embodiments are not intended to limit the present application. For any person skilled in the art, many possible changes and modifications, or equivalent embodiments of the above disclosed technical content can be made to the technical solution of the present application without departing from the scope of the technical solution of the present application. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application, without departing from the content of the technical solution of the present application, shall still fall within the scope of protection of the technical solution of the present application.

Claims

1. A focusing water jet enhancement device based on the Coanda effect, characterized in that, The system includes an enhanced injector, a main pump, a main pump diversion valve, an auxiliary pump, an auxiliary pump diversion valve, a five-way valve, and a water tank. The main pump is connected to the inlet end of the enhanced injector, and the main pump and the enhanced injector are connected to the water tank through the main pump diversion valve. The auxiliary pump is connected to the inlet end of the five-way valve, and the auxiliary pump and the five-way valve are connected to the water tank through the auxiliary pump diversion valve. The outlet end of the five-way valve is connected to the outlet end of the enhanced injector.

2. The focusing water jet enhancement device based on the Coanda effect according to claim 1, characterized in that, The enhanced injector is equipped with a water inlet pipe at its inlet end and a Coanda flow guide nozzle at its outlet end. A flow stabilizer is installed between the water inlet pipe and the Coanda flow guide nozzle. The end of the water inlet pipe opposite to the flow stabilizer is connected to the main pump, and the Coanda flow guide nozzle is connected to the outlet end of the five-way valve.

3. The focusing water jet enhancement device based on the Coanda effect according to claim 2, characterized in that, The Konda flow guide nozzle is arranged sequentially along the direction from the inlet end of the enhanced ejector to the outlet end of the enhanced ejector as follows: first cycloidal flow guide zone, first straight column flow guide zone, first contraction flow guide zone, second straight column flow guide zone, second cycloidal flow guide zone, third straight column flow guide zone, second contraction flow guide zone, nozzle outlet straight column section, and high-pressure low-speed water flow inlet section.

4. The focusing water jet enhancement device based on the Coanda effect according to claim 3, characterized in that, There are four high-pressure, low-speed water flow inlet sections, which are evenly distributed around the nozzle outlet straight column section. Each high-pressure, low-speed water flow inlet section is connected to the outlet end of the five-way valve.

5. The focusing water jet enhancement device based on the Coanda effect according to claim 2, characterized in that, The flow stabilizer is equipped with axial flow guide ribs. There are multiple axial flow guide ribs that are evenly distributed around the inside of the flow stabilizer. The head and tail of the axial flow guide ribs are arc-shaped.

6. The focusing water jet enhancement device based on the Coanda effect according to claim 1, characterized in that, Main pump pressure P z With auxiliary pump pressure P f The proportional relationship between them is 0.92p f ≤P z ≤0.98p f Main pump flow rate Q Z With auxiliary pump flow rate Q f The ratio between them is 12Q f ≤Q z ≤15Q f 7. The focusing water jet enhancement device based on the Coanda effect according to claim 3, characterized in that, The nozzle outlet straight column section outlet diameter Using dimensional references, the diameters of the cycloidal generating circles in the first cycloidal guide region (A1), the second cycloidal guide region (A2), and the first cylindrical guide region (diameter) are defined as follows: Diameter of the second straight column drainage area Diameter of the third straight column drainage area High-pressure, low-velocity water flow inlet section diameter Inlet pipe diameter Stabilizer duct diameter The proportional relationship is: A1=1.56φD0 A2=0.94φD0 φD1=4.0φD0 φD2=3.2φD0 φD3=1.3φD0 φD j =φD k =(7~8)φD0 8. The focusing water jet enhancement device based on the Coanda effect according to claim 3, characterized in that, The contraction angle β between the first and second contraction drainage zones; the design value of the inclination angle δ between the high-pressure, low-velocity water flow inlet section and the axis of the Coanda guide nozzle: β＝12°～13° δ = 30°~40° 9. The focusing water jet enhancement device based on the Coanda effect according to claim 3, characterized in that, Cycloidal parameter equations for the first cycloidal guide region: Whereθ=π Cycloidal parameter equations for the second cycloidal guide region: Whereθ=π

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