Water spraying coupling spray head

Abstract

The invention discloses a water spraying coupling spray head which comprises a water inlet cavity, a water spraying nozzle, a probe, a reverse flow channel and a partition structure plate. The probe is embedded into an inner cavity of the water spray nozzle to form an annular gap; the reverse flow channel comprises a water inlet section, a corner section and an outlet section which are sequentially communicated, and the outlet section is eccentrically communicated with the inner cavity in the radial direction; the partition structure plate is arranged in the annular gap and divides the annular gap into a rotational flow area and a standing area, and the axial distance between the tail end of the corner section and the starting end of the closing-in structure is not smaller than half of the internal hole diameter. After liquid is subjected to primary bubble separation through the reverse flow channel corner section, the liquid enters the rotational flow area through the eccentric outlet section to form rotational flow to expel bubbles, the separation structure plate prevents the bubbles from entering the standing area, the bubbles in the standing area fully escape, and finally the bubbles are shrunk into a laminar stable water column through the closing-in structure. Bubbles can be efficiently removed in the spray head, a stable laminar flow water column is generated, and the ultrasonic flaw detection precision is improved.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic nondestructive testing technology, and more specifically, to a water spray coupling nozzle. Background Technology

[0002] Water-coupled nozzles are widely used in the field of ultrasonic non-destructive testing. Their core function is to form a continuous, uniform, and bubble-free coupling water layer between the probe and the workpiece under test. The quality of the coupling water layer directly determines the transmission efficiency of ultrasonic waves and the stability of the detection signal, thus affecting the accuracy and reliability of the flaw detection results.

[0003] In existing technologies, common water-jet coupling nozzles typically employ a straight-through or simple curved pipe flow channel structure. The coupling liquid (usually water) enters the nozzle's internal cavity through the inlet, flows directly over the probe surface, and is then ejected from the nozzle outlet. While this type of nozzle has a simple structure and low manufacturing cost, it suffers from significant technical drawbacks in practical applications. Specifically, air bubbles inevitably mix into the liquid during transport and flow. These bubbles, entering the nozzle's internal cavity along with the liquid, easily adhere to the probe surface or remain suspended in the coupling water layer, causing ultrasonic signal attenuation, scattering, or even interruption, severely impacting detection quality.

[0004] To address the bubble problem, some existing nozzles incorporate independent bubble separation devices, such as sedimentation tanks, filters, or vacuum degassing equipment, before the liquid enters the nozzle to reduce the gas content in the liquid. However, this pretreatment method increases the overall complexity and size of the system and makes it difficult to eliminate newly generated or residual microbubbles during the flow process inside the nozzle.

[0005] Furthermore, some improved nozzles attempt to incorporate labyrinthine or spiral flow channels internally to achieve natural bubble buoyancy by extending the liquid flow path or altering the flow direction. However, such structures often lead to a significant increase in channel resistance, and the swirling or turbulent flow itself easily breaks up bubbles and entrains them into the deeper layers of the liquid, thus increasing the difficulty of bubble separation. More importantly, after passing through the complex internal flow channels, the outlet water column typically exhibits turbulent or jet-like flow, making it difficult to form a stable laminar water column. The turbulent water column, upon impacting the workpiece surface, easily draws in external air, further exacerbating the bubble problem within the coupled water layer.

[0006] On the other hand, the nozzle structure at the nozzle outlet has a decisive influence on the final shape of the water column. In existing technologies, the selection of the nozzle angle often relies on experience or simple geometric relationships, lacking a systematic matching with factors such as the nozzle's internal orifice diameter and flow channel structure. This leads to uneven velocity distribution and boundary layer separation during water column contraction, resulting in divergent or pulsating water columns, which cannot meet the stringent requirements of high-precision ultrasonic testing for the uniformity and stability of the coupled water layer.

[0007] In summary, existing water jet coupling nozzles still have shortcomings in terms of bubble suppression, water column stability, and structural integration. There is an urgent need for a water jet coupling nozzle that can achieve efficient bubble separation and generate a stable laminar water column without adding complex external equipment. Summary of the Invention

[0008] To overcome the above-mentioned defects of the prior art, embodiments of the present invention provide a water spray coupling nozzle.

[0009] To achieve the above objectives, the innovative aspects of this invention are as follows:

[0010] Water inlet chamber;

[0011] The water nozzle has an internal cavity and an outlet end. The outlet end is provided with a tapered constriction structure with a constriction angle θ.

[0012] The probe is axially embedded into the internal cavity from the rear end of the nozzle, and an annular gap is formed between the probe and the inner wall of the nozzle.

[0013] The reverse flow channel includes an inlet section, a corner section, and an outlet section connected in sequence. The inlet section is connected to the inlet chamber, and the outlet section is connected to the internal cavity along the radial direction of the nozzle. The connection point between the outlet section and the internal cavity is offset from the axis of the internal cavity.

[0014] The partition structure plate is set in the annular gap, located between the end of the outlet section and the beginning of the converging structure. It extends from the inner wall of the nozzle towards the probe. A flow channel is formed between the partition structure plate and the outer wall of the probe. The partition structure plate divides the annular gap axially into a swirling area near the outlet section and a stationary area near the converging structure.

[0015] The liquid enters the reverse flow channel through the inlet chamber, changes its flow direction and is buffered at the corner section, and then enters the internal cavity radially through the outlet section, forming a swirling flow in the swirling zone, which partially submerges the probe and causes the bubbles to escape to the rear end of the internal cavity.

[0016] The end of the corner section is the connection between the outlet section and the internal cavity, and the beginning of the constriction structure is the junction between the internal cavity and the constriction structure. The axial distance L between the end of the outlet section and the beginning of the constriction structure and the internal aperture D of the internal cavity satisfy: L≥0.5D, so that the liquid can obtain sufficient settling time in the settling zone.

[0017] The constriction structure is used to shrink the bubble-free liquid after it has been allowed to stand into a laminar, bubble-free, stable water column.

[0018] Furthermore, the outlet section is connected to the internal cavity along the tangential direction of the nozzle.

[0019] Furthermore, the internal aperture D of the internal cavity is larger than the outer diameter of the probe, and the closing angle θ is linearly inversely proportional to the internal aperture D.

[0020] Furthermore, the closing angle θ and the internal aperture D satisfy the following relationship: 110°+900°×mm / D≤θ≤110°+1300°×mm / D, where D is in millimeters.

[0021] Furthermore, the corner segment can be a right-angle corner or a rounded corner.

[0022] Furthermore, the spray nozzle is made of acrylic material, and the surface finish of its inner wall is no higher than Ra1.6.

[0023] Furthermore, the present invention also includes at least one sealing ring disposed between the probe and the inner wall of the nozzle.

[0024] Furthermore, the water inlet chamber and the spray nozzle are integrally formed or can be detachably connected by threads.

[0025] Furthermore, when the nozzle is used for ultrasonic testing, after the stable water column impacts the workpiece surface, a coupling water layer is formed between the probe and the workpiece. The thickness of this coupling water layer is determined by the distance between the nozzle outlet and the workpiece surface, and the stability of the stable water column ensures the uniformity of the coupling water layer and the consistency of the ultrasonic testing signal.

[0026] Furthermore, the partition structure plate is a ring-shaped plate or an arc-shaped plate, arranged circumferentially along the inner wall of the spray nozzle.

[0027] The technical effects and advantages of this invention are as follows:

[0028] 1. This invention achieves efficient and compact bubble separation inside the nozzle through the synergistic arrangement of a reverse flow channel, an eccentrically positioned outlet section, a partition structure plate, and a specific axial distance configuration. Specifically, the liquid undergoes a sudden change in flow direction at the corner section of the reverse flow channel, achieving initial bubble separation; subsequently, it enters the swirling zone radially in an eccentric manner, where centrifugal force drives the bubbles to the upper part of the annular gap; the partition structure plate physically blocks the bubbles in the swirling zone, ensuring that the liquid entering the settling zone is bubble-free; simultaneously, by limiting the axial distance L between the end of the corner section and the beginning of the closing structure to no less than half the internal aperture D, sufficient settling time is provided for the liquid in the settling zone, allowing residual bubbles to completely escape. This structure eliminates the need for an external independent degassing device, achieving efficient bubble suppression and removal inside the nozzle, significantly simplifying the system configuration and reducing equipment costs and maintenance difficulty.

[0029] 2. This invention, through optimized matching of the constriction angle and internal aperture, combined with the aforementioned bubble removal structure, can generate a laminar, bubble-free water column with highly stable flow direction. Specifically, the bubble-free liquid, after being allowed to settle and degassed, enters the constriction structure. The constriction angle θ and the internal aperture D satisfy the preferred relationship of 110+900 / D≤θ≤110+1300 / D, ensuring uniform flow velocity distribution and a stable boundary layer during the contraction process. This avoids turbulence caused by excessively steep contraction or water column dispersion caused by excessively slow contraction. The resulting stable laminar water column, after impacting the workpiece surface, forms a uniform and continuous coupled water layer between the probe and the workpiece, effectively ensuring the consistency and reliability of the ultrasonic flaw detection signal and significantly improving detection accuracy and repeatability. Attached Figure Description

[0030] Figure 1 This is a side cross-sectional view of an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the liquid flow path in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram showing the relationship between the closing angle θ and the internal aperture D in an embodiment of the present invention.

[0033] Explanation of the labels in the diagram:

[0034] 1-Inlet chamber; 2-Spray nozzle; 11-Annular gap; 21-Internal cavity; 22-Constriction structure; 23-Outlet end; 3-Probe; 4-Reverse flow channel; 41-Inlet section; 42-Corner section; 43-Outlet section; 5-Sealing ring; 6-Stabilized water column; 7-Workpiece; D-Internal aperture; L-Axial distance between the end of the outlet section and the beginning of the constriction structure; θ-Constriction angle; 8-Separation structure plate; 12-Swirl zone; 13-Stationary zone. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1

[0037] like Figure 1 As shown, this embodiment provides a water spray coupling nozzle, which mainly includes a water inlet chamber 1, a water nozzle 2, a probe 3, and a reverse flow channel 4.

[0038] Specifically, the nozzle 2 has an internal cavity 21 and an outlet end 23. The outlet end 23 is provided with a tapered constriction structure 22, which has a specific constriction angle θ. The probe 3 is axially embedded into the internal cavity 21 from the rear end of the nozzle 2. The outer diameter of the probe 3 is smaller than the internal aperture D of the internal cavity 21, so that an annular gap 11 is formed between the probe 3 and the inner wall of the nozzle 2.

[0039] The reverse flow channel 4 is one of the core structures of this invention, comprising an inlet section 41, a corner section 42, and an outlet section 43 connected in sequence. The inlet section 41 is connected to the inlet chamber 1 and is used to receive the coupling liquid (such as water) supplied from the outside. The outlet section 43 is connected to the internal cavity 21 along the radial direction of the nozzle 2, and the connection point between the outlet section 43 and the internal cavity 21 (i.e., the end of the outlet section 43) is offset from the axis of the internal cavity 21. In this embodiment, the connection point is located at the upper part of the internal cavity 21 to achieve eccentric liquid inlet.

[0040] like Figure 1 and Figure 2 As shown, a partition plate 8 is provided within the annular gap 11. This partition plate 8 is located between the end of the outlet section 43 and the beginning of the converging structure 22, extending from the inner wall of the nozzle 2 towards the probe 3. A gap is maintained between the partition plate 8 and the outer wall of the probe 3, forming a flow channel. The partition plate 8 clearly divides the annular gap 11 axially into two functional zones: a swirling zone 12 near the outlet section 43 and a stationary zone 13 near the converging structure 22.

[0041] The working principle and process of this invention are as follows, which can be referred to in detail. Figure 2 The liquid flow path in the image (shown by the solid black arrow):

[0042] First, the coupling liquid enters the inlet section 41 of the reverse flow channel 4 from the inlet chamber 1. When the liquid flows through the corner section 42, the flow direction changes drastically, forming a preliminary stabilization and bubble separation effect. Some large bubbles are initially suppressed here due to inertia.

[0043] Subsequently, the liquid is injected radially and eccentrically into the swirling zone 12 of the internal cavity 21 at high speed through the outlet section 43. Due to the eccentric setting of the outlet section 43, the liquid forms a strong swirling flow within the annular gap 11. Under the centrifugal force generated by the swirling flow, residual air bubbles in the liquid are effectively driven to the upper part of the annular gap 11 (i.e., the area near the inner wall of the nozzle 2), achieving efficient separation of air bubbles from the liquid. At the same time, the swirling flow partially immerses the probe 3 in the liquid, ensuring the coupling effect of the probe 3.

[0044] Next, the liquid continues to flow in the swirling zone 12. When it reaches the partition plate 8, the bubbles that have accumulated in the upper part of the swirling zone 12 are physically blocked by the partition plate 8 and cannot enter the downstream. The bubble-free liquid flows smoothly into the settling zone 13 through the flow channel between the partition plate 8 and the outer wall of the probe 3.

[0045] Within the settling zone 13, the liquid is no longer disturbed by the swirling flow and enters a laminar flow state. At this point, any tiny residual bubbles have ample time to rise and escape. Figure 1 As shown, in this embodiment, the axial distance L between the end of the outlet section 43 and the beginning of the constriction structure 22 (i.e., the junction of the internal cavity 21 and the constriction structure 22) is designed to be greater than or equal to 0.5 times the internal aperture D (i.e., L≥0.5D). This dimensional relationship ensures that the liquid has sufficient settling time in the settling zone 13, allowing the bubbles to escape fully.

[0046] Finally, the bubble-free liquid, after settling and complete degassing, enters the converging structure 22. The converging structure 22, with its specific converging angle θ, smoothly contracts and guides the liquid, ultimately ejecting a laminar, bubble-free, and highly stable water column 6 from the outlet end 23. In ultrasonic testing applications, after this stable water column 6 impacts the surface of the workpiece 7, a uniform coupling water layer is formed between the probe 3 and the workpiece 7. The thickness of this coupling water layer is determined by the distance between the outlet end 23 of the nozzle 2 and the surface of the workpiece 7, and the stability of the stable water column 6 directly ensures the uniformity of the coupling water layer and the consistency and reliability of the ultrasonic testing signal.

[0047] Example 2

[0048] This embodiment optimizes the connection between the outlet section 43 of the reverse flow channel 4 and the internal cavity 21, based on Embodiment 1. Specifically, the outlet section 43 is connected to the internal cavity 21 along the tangential direction of the nozzle 2. Compared with the ordinary radial connection, this tangential connection can impart a larger tangential velocity component to the liquid entering the swirling zone 12, thereby generating a stronger swirling effect and further improving the efficiency of bubble separation.

[0049] Example 3

[0050] This embodiment specifies the parameters of the constriction structure 22. The internal aperture D of the internal cavity 21 is larger than the outer diameter of the probe 3, which is the basis for forming the annular gap 11. Through extensive computational fluid dynamics (CFD) simulations and physical sample experiments, the inventors discovered that there is a synergistic relationship between the constriction angle θ and the internal aperture D, specifically a linear inverse relationship. To obtain the best flow stabilization effect and avoid turbulence or divergence of the water column, the constriction angle θ and the internal aperture D should satisfy the following preferred relationship:

[0051] 110°+900°×mm / D≤θ≤110°+1300°×mm / D

[0052] The unit of D is millimeters (mm).

[0053] like Figure 3 As shown in the figure, this optimal relationship is clearly illustrated. Figure 3 The horizontal axis represents the internal aperture D (unit: mm), and the vertical axis represents the taper angle θ (unit: °). In the figure, the dashed line represents the lower limit curve 110° + 900° × mm / D, another dashed line represents the upper limit curve 110° + 1300° × mm / D, and the solid line in the middle is the reference curve θ = 110° + 1200° × mm / D. The gray shaded area between the curves represents the preferred range of the taper angle θ.

[0054] For example, when the internal orifice diameter D is 80 mm, the preferred range for the closing angle θ is approximately 121.25° to 126.25°. Point A in the figure (D=80 mm, θ≈125°) falls within this preferred range, suitable for high flow rate conditions. When the internal orifice diameter D is 100 mm, point B (D=100 mm, θ≈122°) is close to the reference curve, suitable for commonly used orifice diameter ranges, and provides optimal water column stability. When the internal orifice diameter D is 140 mm, point C (D=140 mm, θ≈118.6°) remains within the upper limit curve, suitable for low flow rate, high flow rate conditions. The design guidelines provided in this figure enable those skilled in the art to quickly determine the optimal closing angle θ based on the actual internal orifice diameter D, without repeated trials.

[0055] Example 4

[0056] This embodiment provides a specific implementation of the corner section 42 in the reverse flow channel 4. The corner section 42 is set as a right-angle corner. This structure is simple to manufacture and can cause a sharp 90° change in the liquid flow direction, thereby achieving efficient preliminary bubble separation.

[0057] Example 5

[0058] As an alternative to Embodiment 4, the corner segment 42 in this embodiment is set as a rounded corner. The rounded corner can reduce the local resistance loss of liquid flow, and while ensuring the bubble separation effect, it provides a smoother flow transition, which is suitable for application scenarios that are sensitive to pressure loss.

[0059] Example 6

[0060] This embodiment specifies the material and surface quality of the spray nozzle 2. The spray nozzle 2 is made of transparent acrylic material, and the surface finish of its inner wall is no higher than Ra1.6. Acrylic material facilitates observation of the internal flow state, while the high-precision surface finish (Ra≤1.6) greatly reduces the frictional resistance of the liquid flow, helps maintain the laminar flow state of the water column, and prevents turbulence caused by rough wall surface.

[0061] Example 7

[0062] To ensure a tight seal between probe 3 and nozzle 2, and to prevent liquid leakage from the rear end, such as... Figure 1 As shown, in this embodiment, at least one sealing ring 5 is provided between the probe 3 and the inner wall of the nozzle 2. The sealing ring 5 can effectively isolate the high-pressure area and ensure that all liquids are sprayed out from the outlet end 23 through the reverse flow channel 4 and the internal cavity 21.

[0063] Example 8

[0064] This embodiment provides a connection method between the water inlet chamber 1 and the spray nozzle 2. Both can be designed as a single molded structure to improve overall structural strength and reduce leakage points. Alternatively, they can be detachably connected by threads, which facilitates cleaning and maintenance of the spray nozzle 2's interior and allows for replacement of different specifications of the spray nozzle 2 according to different operating conditions.

[0065] Example 9

[0066] This embodiment further defines the specific structural form of the partition plate 8. The partition plate 8 can be an annular plate, that is, a complete annular protrusion is provided around the inner wall of the nozzle 2 to form a 360° barrier, which has the best effect in blocking air bubbles. Alternatively, the partition plate 8 can also be multiple arc-shaped plates, which are spaced apart around the inner wall of the nozzle 2. This structure can provide more liquid flow channels while ensuring the blocking of air bubbles.

[0067] In summary, this invention achieves efficient online bubble separation and suppression through the synergistic effect of multiple structures, including the reverse flow channel 4, the eccentrically positioned outlet section 43, the partition structure plate 8, and the parameter-optimized closing structure 22, ultimately producing a stable laminar water column. The aforementioned embodiments optimize the technical features from different perspectives, comprehensively and powerfully supporting the scope of protection defined by claims 1-10.

[0068] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0069] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0070] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A water spray coupling nozzle, characterized in that: Its structure includes: Water inlet chamber; A water nozzle, wherein the water nozzle has an internal cavity and an outlet end, the outlet end is provided with a tapered constriction structure, the constriction structure having a constriction angle θ; The probe is axially embedded into the internal cavity from the rear end of the nozzle, and an annular gap is formed between the probe and the inner wall of the nozzle. A reverse flow channel, comprising an inlet section, a corner section, and an outlet section connected in sequence, wherein the inlet section is connected to the inlet cavity, and the outlet section is connected to the internal cavity along the radial direction of the nozzle, and the connection point between the outlet section and the internal cavity is offset from the axis of the internal cavity. A partition structure plate is disposed within the annular gap, located between the end of the outlet section and the beginning of the converging structure, extending from the inner wall of the nozzle toward the probe. A flow channel is formed between the partition structure plate and the outer wall of the probe. The partition structure plate axially divides the annular gap into a swirling zone near the outlet section and a stationary zone near the converging structure. The liquid enters the reverse flow channel through the inlet chamber, changes its flow direction and is buffered at the corner section, and then enters the internal cavity radially through the outlet section, forming a swirling flow in the swirling zone, which partially submerges the probe and causes the air bubbles to escape towards the rear end of the internal cavity. The end of the corner section is the connection between the outlet section and the internal cavity, and the starting end of the constriction structure is the junction between the internal cavity and the constriction structure. The axial distance L between the end of the outlet section and the starting end of the constriction structure and the internal aperture D of the internal cavity satisfy: L≥0.5D, so that the liquid can obtain sufficient settling time in the settling area. The constriction structure is used to shrink the bubble-free liquid after it has been allowed to stand into a laminar, bubble-free, stable water column.

2. The water spray coupling nozzle according to claim 1, characterized in that: The outlet section communicates with the internal cavity along the tangential direction of the nozzle.

3. A water spray coupling nozzle according to claim 1, characterized in that: The internal aperture D of the internal cavity is larger than the outer diameter of the probe, and the closing angle θ is linearly inversely proportional to the internal aperture D.

4. A water spray coupling nozzle according to claim 1, characterized in that: The closing angle θ and the internal aperture D satisfy the following relationship: 110°+900°×mm / D≤θ≤110°+1300°×mm / D, where D is in millimeters.

5. A water spray coupling nozzle according to claim 1, characterized in that: The corner segment is either a right-angle corner or a rounded corner.

6. A water spray coupling nozzle according to claim 1, characterized in that: The spray nozzle is made of acrylic material, and the surface finish of its inner wall is no higher than Ra1.

6.

7. A water spray coupling nozzle according to claim 1, characterized in that: It also includes at least one sealing ring disposed between the probe and the inner wall of the nozzle.

8. A water spray coupling nozzle according to claim 1, characterized in that: The water inlet chamber and the water nozzle are integrally formed or can be detachably connected by threads.

9. A water spray coupling nozzle according to claim 1, characterized in that: When the nozzle is used for ultrasonic testing, the stable water column forms a coupling water layer between the probe and the workpiece after impacting the workpiece surface. The thickness of the coupling water layer is determined by the distance between the nozzle outlet and the workpiece surface, and the stability of the stable water column ensures the uniformity of the coupling water layer and the consistency of the ultrasonic testing signal.

10. A water spray coupling nozzle according to claim 1, characterized in that: The partition structure plate is an annular plate or an arc-shaped plate, and is arranged circumferentially along the inner wall of the spray nozzle.

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