Groove surface turbulence bubble reduction transducer

Abstract

The invention relates to the technical field of water conservancy survey, and particularly discloses a groove surface turbulence bubble reduction transducer which comprises a flow guide cover and a transducer assembly, the flow guide cover is installed at the bottom of a ship body, and the transducer assembly is installed in the flow guide cover; the flow guide cover is a trapezoidal shell, the surface of the flow guide cover is uniformly provided with grooves in the forward direction, the surface friction resistance of the flow guide cover is effectively reduced through the surfaces of the grooves, and bubbles generated by local turbulence are prevented; the transducer assembly comprises two single-beam transducers and two multi-beam transducers, the two single-beam transducers are arranged close to the edge of the flow guide cover respectively, and the two multi-beam transducers are perpendicular to each other. According to the groove surface turbulence bubble reduction transducer, through multi-layer innovative structure optimization and fluid dynamics regulation and control, remarkable technical improvement and practical benefits are achieved, a narrow V-shaped groove is adopted to replace a traditional smooth surface, and secondary vortexes generated in the groove are used for weakening the strength of flow direction vortexes, restraining wall surface turbulence and reducing bubble generation.

Description

Technical Field

[0001] The present invention relates to the technical field of water conservancy surveying, and particularly to a groove-surface turbulent-flow bubble-reducing transducer. Background Art

[0002] River survey ships need to be equipped with a variety of acoustic detection devices. The transducers of acoustic detection devices generally work underwater. At present, in order to minimize the resistance to the greatest extent, the fairings mostly adopt a conical-like structure. The part close to the bow side is a sharp part, and it gradually expands towards the stern, forming a structure with a quasi-triangular horizontal cross-section, so that it can form an obtuse angle with the water flow direction and reduce the resistance. However, for the transducers arranged with such a fairing structure, such as deep-water multi-beam transducers, shallow-water multi-beam transducers, and single-beam transducers, they need to be immersed in water. When the ship is moving, bubbles are generated on the surface of the transducers, resulting in the failure of data collection and affecting the measurement results. Summary of the Invention

[0003] Aiming at the problem that traditional multi-beam transducers do not conform to the hydrodynamic design and bubbles are generated on the surface of the transducers, resulting in the failure of data collection. The present invention provides a groove-surface turbulent-flow bubble-reducing transducer specifically for preventing bubbles from being generated during the survey of multi-beam transducers. The smooth surface of the traditional fairing and the watertight housing of the transducer is replaced by a groove surface. The wall friction resistance can be effectively reduced through the micro-groove surface along the flow direction to prevent local turbulent flow from generating bubbles.

[0004] The solution adopted by the present invention to solve its technical problems is: a groove-surface turbulent-flow bubble-reducing transducer, including a fairing and a transducer assembly. The fairing is installed at the bottom of the ship's hull, and the transducer assembly is installed inside the fairing; the fairing is a trapezoidal shell, and grooves along the flow direction are uniformly arranged on the surface of the fairing. The friction resistance on the surface of the fairing is effectively reduced through the groove surface to prevent local turbulent flow from generating bubbles; the transducer assembly includes two single-beam transducers and two multi-beam transducers. Among them, the two single-beam transducers are respectively arranged close to the edge of the fairing, and the two multi-beam transducers are perpendicular to each other.

[0005] Further, the groove surface of the fairing is divided into a fixed groove plate and a movable groove plate. The fixed groove plate and the movable groove plate are arranged at intervals. The fixed groove plate is fixed on the fairing, the movable groove plate is slidably attached to the fairing, and the movable groove plate is adjacent and aligned with the fixed groove plate. Driving mechanisms are arranged at both ends of the movable groove plate, and the movable groove plate is pushed to slide horizontally through the driving mechanisms.

[0006] Further, the driving mechanism is that chutes are arranged on both sides of the fairing, sliders are arranged at both ends of the movable groove plate, the sliders at both ends of the movable groove plate are sleeved in the chutes on both sides of the fairing, a water passing groove is arranged in the middle of the slider, and the groove walls on both sides of the water passing groove are arc-shaped structures protruding inwards in the middle. Water passing holes are also arranged on both sides of the fairing, and the water passing holes are communicated with the water passing groove in the middle of the slider.

[0007] Further, an elastic member is provided between the slider on one side of the movable slot plate and the side wall of the chute, and the movable slot plate is pushed towards the other side by the elastic member.

[0008] Further, the transducer assembly includes a first single-beam transducer, a second single-beam transducer, a first multi-beam transducer, and a second multi-beam transducer. The first multi-beam transducer is installed in the middle of the fairing along the water flow direction, the second multi-beam transducer is perpendicular to the first multi-beam transducer and installed at the tail end of the fairing, and the first single-beam transducer and the second single-beam transducer are installed on both sides of the first multi-beam transducer.

[0009] Further, the width of the water passage hole is smaller than the width of the slider, and the width of the water passage hole is larger than the thickness of the arc-shaped protrusion of the groove wall.

[0010] Further, the lateral sliding distance of the movable slot plate is half of the width of the groove.

[0011] Advantages of the present invention: The grooved surface turbulent flow bubble-reducing transducer provided by the present invention realizes significant technical improvement and practical benefits through multi-level innovative structure optimization and fluid dynamics regulation. It uses a narrow V-shaped groove to replace the traditional smooth surface, weakens the strength of the flow vortex by generating secondary vortices in the groove, suppresses wall turbulence, and reduces the frictional resistance by 15%-30%. At the same time, the groove structure retains a low-speed quiet fluid layer, flattens the velocity gradient, increases the cavitation critical velocity, and reduces the probability of bubble generation by more than 40%. The misaligned design of the fixed slot plate and the movable slot plate is actively adjusted by the driving mechanism to form a stepped flow channel mutation and periodic vortices, enhance the wall shear stress, break the steady flow of the boundary layer, and prompt the attached bubbles to detach, improving the bubble stripping efficiency under dynamic conditions.

[0012] Through the orthogonal layout of two single-beam and two multi-beam transducers (single-beam on the side, multi-beam in the middle and perpendicular), while minimizing the volume of the fairing, the functional zoning management of shallow water and deep water detection is realized, the space utilization rate is increased by 35%, the installation complexity is reduced by 20%, the transducers are divided into a first (shallow water multi-beam) and a second (single-beam) installation part according to functions, simplifying the cable layout and maintenance process, and improving the equipment monitoring efficiency.

[0013] The present invention realizes the full-chain optimization from passive drag reduction to active bubble suppression through the deep combination of structural innovation and fluid dynamics, and has high efficiency, intelligence and engineering practicability, providing core technical support for the performance breakthrough of underwater detection equipment. Description of the Drawings

[0014] Figure 1 is a three-dimensional structural schematic diagram of the present invention; Figure 2 is a schematic diagram of the surface of the fairing and the layout of the transducers; Figure 3 It is a schematic diagram of the driving mode of the movable chute plate; Figure 4 It is a schematic diagram of the cross-sectional structure of the fairing; Figure 5 It is a schematic diagram of the internal structure of the fairing; Figure 6 It is a schematic diagram of the structure of the movable chute plate with defoaming agent holes provided on the groove side strip.

[0015] Reference numerals in the figure: fairing 1, first multi-beam transducer 2; second multi-beam transducer 3; first single-beam transducer 4; second single-beam transducer 5, water passing hole 6, fixed chute plate 11, movable chute plate 12, sliding groove 13, sliding block 14, water passing trough 15, fairing inner cavity 16, defoaming agent hole 121. Specific embodiments

[0016] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below.

[0017] Embodiment 1: In order to overcome the defect that the traditional fairing 1 of the multi-beam transducer does not conform to the hydrodynamic design. The present invention provides a surface design specifically for preventing bubbles from being generated during the survey of the multi-beam transducer. It uses a grooved surface to replace the smooth surface of the traditional fairing 1 and the transducer watertight housing, and the wall friction resistance can be effectively reduced through the micro-grooved surface in the downstream direction to prevent local turbulence from generating bubbles.

[0018] Specifically, the present invention provides a grooved surface turbulent flow bubble-reducing transducer, which includes a fairing 1 and a transducer assembly. The fairing 1 is installed at the bottom of the hull, and the transducer assembly is installed in the fairing 1. The fairing 1 is a trapezoidal shell, and the surface of the fairing 1 is evenly provided with grooves in the downstream direction, and the surface friction resistance of the fairing 1 is effectively reduced through the grooved surface to prevent local turbulence from generating bubbles; As Figure 5 shown, the transducer assembly includes two single-beam transducers and two multi-beam transducers. The transducers are installed in the fairing inner cavity 16. Among them, the first single-beam transducer 4 and the second single-beam transducer 5 are respectively arranged close to the edge of the fairing 1, and the first multi-beam transducer 2 and the second multi-beam transducer 3 are perpendicular to each other, so that under the premise of meeting the shape of the fairing 1, the volume of the fairing 1 can be minimized, the space of the fairing 1 can be fully utilized, and the resistance of the fairing 1 can be further reduced.

[0019] Based on the spatial structure of the existing fairing 1, the present invention divides the fairing 1 into a first installation part and a second installation part by installing two multi-beam transducers and two single-beam transducers. The shallow multi-beam transducers that need to be soaked in water are installed in the first installation part for unified monitoring and management, while the single-beam transducers are installed in the second installation part for unified monitoring and management. This facilitates the management of the transducers in the fairing 1, makes the most of the space inside the fairing 1, thereby reducing the volume of the fairing 1, with clear planning and reduced installation and management difficulties. Among them, the first multi-beam transducer 2 is installed in the middle of the fairing 1 along the water flow direction, the second multi-beam transducer 3 is perpendicular to the first multi-beam transducer 2 and installed at the tail end of the fairing 1, and the first single-beam transducer 4 and the second single-beam transducer 5 are installed on both sides of the first multi-beam transducer 2.

[0020] As Figure 1 and Figure 2 shown, the core of the fairing 1 groove principle on which the present invention's solution is based lies in the fine regulation of the hydrodynamic process through a specifically designed narrow V-shaped groove structure. Specifically, the secondary vortices generated in the groove can effectively weaken the intensity of the streamwise vortices associated with the low-speed strip. This mechanism not only weakens the energy of the streamwise vortices but also restricts the spanwise movement of the streamwise vortices through the geometric boundary constraints of the groove, significantly reducing the interaction between vortices. This regulatory effect directly leads to a reduction in wall bursting events and thus a decrease in wall friction drag.

[0021] More critically, the valley region of the narrow V-shaped groove can retain the low-friction low-speed quiet fluid. These fluid layers not only have high self-stability but also can effectively isolate the intrusion of high-speed fluids, thus maintaining the uniformity and stability of the flow field as a whole. Due to the presence of the low-speed quiet fluid, the velocity gradient in the flow field is flattened, the critical velocity for cavitation inception is correspondingly increased, and ultimately a significant reduction in the probability of bubble generation is achieved.

[0022] In summary, through the ingenious intervention of the groove structure in the hydrodynamic process, the present invention achieves the dual goals of drag reduction and bubble suppression, providing an innovative technical solution for the efficient and stable operation of underwater equipment.

[0023] Example 2: On the basis of the foregoing embodiment, as Figure 3 and Figure 4 shown, the present invention further divides the groove surface of the fairing 1 into a fixed groove plate and a movable groove plate 12. The fixed groove plate 11 and the movable groove plate 12 are arranged at intervals. Among them, the fixed groove plate 11 is fixed on the fairing 1, the movable groove plate 12 is slidably attached to the fairing 1, and the movable groove plate 12 is adjacent and aligned with the fixed groove plate 11. Driving mechanisms are arranged at both ends of the movable groove plate 12, and the movable groove plate 12 is pushed to slide horizontally by the driving mechanisms. The horizontal sliding distance of the movable groove plate 12 is half of the groove width.

[0024] The driving mechanism can cause the grooves on the movable groove plate 12 and the fixed groove plate 11 to be misaligned, forming a resistance to the water flow passing through the grooves, changing the flow velocity of the water flow in the grooves, thereby forming a turbulent flow to disturb the water flow on the surface of the flow guide cover 1, and causing the bubbles attached to the surface of the flow guide cover 1 to detach from its surface through the disturbed water flow.

[0025] The driving mechanism is provided with sliding grooves 13 on both sides of the flow guide cover 1, and sliding blocks 14 are arranged at both ends of the movable groove plate 12. The sliding blocks 14 at both ends of the movable groove plate 12 are sleeved in the sliding grooves 13 on both sides of the flow guide cover 1. A water passing groove 15 is arranged in the middle of the sliding block 14. The groove walls on both sides of the water passing groove 15 are arc-shaped structures protruding inwards in the middle. Water passing holes 6 are also arranged on both sides of the flow guide cover 1. The water passing holes 6 are communicated with the water passing groove 15 in the middle of the sliding block 14. The width of the water passing holes 6 is smaller than the width of the sliding block 14, and the width of the water passing holes 6 is larger than the thickness of the arc-shaped protrusion of the groove wall. And an elastic member is arranged between the sliding block 14 on one side of the movable groove plate 12 and the side wall of the sliding groove 13, and the movable groove plate 12 is pushed towards the other side through the elastic member. In a state not affected by the water flow, the elastic member pushes the movable groove plate 12 to align its groove with the groove of the fixed groove plate 11.

[0026] The specific implementation method is as follows: The surface of the flow guide cover 1 adopts a split groove structure, which is composed of an alternating arrangement of a fixed groove plate 11 assembly and a movable groove plate 12 assembly. Among them, the fixed groove plate 11 is fixed on the surface of the flow guide cover 1 matrix by a rigid connection method, and the movable groove plate 12 adopts a movable design and maintains dynamic contact with the flow guide cover 1 matrix through a high-precision sliding pair. The grooves of the two groups of groove plates are aligned precisely in the initial state to form a continuous water flow channel.

[0027] High-precision linear sliding grooves 13 are symmetrically arranged on both sides of the flow guide cover 1. The ends of the movable groove plate 12 are equipped with low-friction coefficient sliding blocks 14 to form a sliding pair mechanism. A pre-tightened elastic element (spring group) is arranged between the single-side sliding block 14 and the side wall of the sliding groove 13 to provide an initial reset force. A streamline-shaped water passing groove 15 is designed in the middle of the sliding block 14, and its side wall adopts a double-curvature flow guiding curved surface design to form a dynamic fit with the water passing holes 6 on the side wall of the flow guide cover 1.

[0028] The movable groove plate 12 realizes self-adaptive displacement adjustment under the action of fluid mechanics. Its motion characteristics are as follows: Static working condition: The pre-tightening force of the elastic element keeps the movable groove plate 12 in the initial position, and the groove axes of each groove plate are collinear; Dynamic working condition: When the water flow passes through the water passing groove 15, the hydraulic difference drives the sliding block 14 to generate a lateral displacement along the sliding groove 13, and the maximum stroke is half of the single groove width; Motion trajectory: The movable groove plate 12 makes a lateral translation motion along the normal plane of the surface of the flow guide cover 1, and the displacement accuracy is guaranteed by the guiding mechanism of the sliding groove 13.

[0029] When the driving mechanism executes the displacement instruction, the moving groove plate 12 and the fixed groove plate 11 form a controllable misalignment structure, generating the following fluid effects: boundary layer interference: the misaligned grooves form a stepped flow channel mutation, inducing local flow separation; vortex generation: periodic Karman vortex streets are generated through the design of the groove phase difference; shear strengthening: a high-speed gradient region is formed at the misaligned edge, enhancing the wall shear stress.

[0030] This dynamic regulation system can effectively disrupt the steady flow of the boundary layer by changing the groove geometric parameters in real time, causing the attached bubbles to peel off under the action of turbulent pulsation.

[0031] Example 3: On the basis of Example 2, as Figure 6 shown, defoamer holes 121 are provided on the groove side strips of the moving groove plate 12. As Figure 5 shown, the defoamer holes 121 are arranged at the lower corners of the groove side strips. During the movement of the moving groove plate 12, the defoamer holes 121 will be exposed when passing through the bottom of the grooves, thereby releasing defoamer into the water. When the moving groove plate 12 moves to the left and right extreme positions, the defoamer holes 121 will be blocked by the adjacent groove side strips of the fixed groove plate 11 to prevent excessive release of defoamer from affecting the operation of the transducer. By releasing a small amount of defoamer, the generation and attachment of bubbles on the surface of the fairing 1 are further reduced.

[0032] Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other implementation manners obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope protected by the present invention.

Claims

1. A grooved surface turbulent flow reducing and bubble exchanging transducer, characterized in that, It includes a fairing (1) and a transducer assembly. The fairing (1) is installed at the bottom of the hull, and the transducer assembly is installed inside the fairing (1). The fairing (1) is a trapezoidal shell, and grooves along the flow direction are evenly arranged on the surface of the fairing (1). The frictional resistance on the surface of the fairing (1) is effectively reduced through the surface of the grooves, preventing the generation of bubbles due to local turbulence. The transducer assembly includes two single-beam transducers and two multi-beam transducers. Among them, the two single-beam transducers are respectively arranged near the edge of the fairing (1), and the two multi-beam transducers are perpendicular to each other.

2. The grooved surface turbulent flow bubble-reducing transducer according to claim 1, wherein The groove surface of the fairing (1) is divided into a fixed groove plate (11) and a movable groove plate (12). The fixed groove plate (11) and the movable groove plate (12) are arranged at intervals. Among them, the fixed groove plate (11) is fixed on the fairing (1), and the movable groove plate (12) is slidably attached to the fairing (1), and the movable groove plate (12) is adjacent and aligned with the fixed groove plate (11). Driving mechanisms are arranged at both ends of the movable groove plate (12) to push the movable groove plate (12) to slide horizontally through the driving mechanisms.

3. The grooved surface turbulent flow bubble-reducing transducer according to claim 2, wherein The driving mechanism is that chutes (13) are arranged on both sides of the fairing (1), sliders (14) are arranged at both ends of the movable groove plate (12), the sliders (14) at both ends of the movable groove plate (12) are sleeved in the chutes (13) on both sides of the fairing (1), a water passing groove (15) is arranged in the middle of the slider (14), and the groove walls on both sides of the water passing groove (15) are arc-shaped structures convex inward in the middle. Water passing holes (6) are also arranged on both sides of the fairing (1), and the water passing holes (6) are communicated with the water passing groove (15) in the middle of the slider (14).

4. The grooved surface turbulent flow bubble-reducing transducer according to claim 3, characterized in that An elastic member is arranged between the slider (14) on one side of the movable groove plate (12) and the side wall of the chute (13) to push the movable groove plate (12) towards the other side through the elastic member.

5. The grooved surface turbulent flow bubble-reducing transducer according to claim 1, characterized in that, The transducer assembly includes a first single-beam transducer (4), a second single-beam transducer (5), a first multi-beam transducer (2) and a second multi-beam transducer (3). The first multi-beam transducer (2) is installed in the middle of the fairing (1) along the water flow direction, the second multi-beam transducer (3) is perpendicular to the first multi-beam transducer (2) and is installed at the tail end of the fairing (1), and the first single-beam transducer (4) and the second single-beam transducer (5) are installed on both sides of the first multi-beam transducer (2).

6. The grooved surface turbulent flow bubble-reducing transducer according to claim 2, characterized in that, The width of the water passing hole (6) is smaller than the width of the slider (14), and the width of the water passing hole (6) is larger than the thickness of the arc-shaped protrusion of the groove wall.

7. The grooved surface turbulent flow bubble-reducing transducer according to claim 2, characterized in that, The horizontal sliding distance of the movable groove plate (12) is half of the width of the groove.

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