Anti-cavitation structure for pump blade inlet

Abstract

The application provides an anti-cavitation structure for a pump blade inlet, belonging to the technical field of fluid machinery anti-cavitation, and comprising a flexible film attached to the leading edge of the suction surface of the blade inlet and a plurality of bionic ribs distributed along the main fluid flow direction, the ribs being integrally formed with the film. The flexible film is fixed through embedded clamping grooves and a sealing glue layer, and covers 5%-15% of the chord length of the blade. The flexible film is made of polyurethane-based or polyether ether ketone-based composite material, with a thickness of 0.08-0.50 mm, and the rib height is 0.05-0.50 mm. When the liquid flows, the structure can induce the boundary layer to form an orderly disturbed flow, and absorb the impact energy of the bubble collapse through the elastic deformation of the flexible film layer, thereby reducing the negative pressure peak of the blade inlet, delaying the occurrence of cavitation, and having the advantages of simple installation, strong replaceability and wide application range.

Description

Technical Field

[0001] This invention relates to the field of anti-cavitation and performance optimization technology for fluid machinery, specifically to an anti-cavitation structure for pump blade inlets, which improves the local flow state at the impeller inlet, reduces negative pressure peaks and the probability of cavitation, and is applicable to impeller-type fluid machinery such as centrifugal pumps, double-suction pumps and mixed-flow pumps. Background Technology

[0002] During pump operation, the liquid is strongly accelerated at the impeller inlet, resulting in a significant drop in local pressure. When this pressure falls below the liquid's saturated vapor pressure, vaporization occurs, forming bubbles. These bubbles, carried by the fluid to the high-pressure zone, collapse rapidly, generating shock waves and microjets. This causes repeated erosion and fatigue damage to the impeller surface, leading to cavitation. Cavitation not only causes pitting, deformation, and noise vibration on the impeller material surface but also disrupts flow continuity, severely impacting the pump's hydraulic performance and service life. Therefore, improving the pump's cavitation resistance is an urgent need in pump design and manufacturing, and is of great significance for improving industrial production efficiency, energy efficiency, and environmental protection.

[0003] The inlet static pressure can be increased by increasing the radius of the blade inlet fillet, adjusting the installation angle, or installing an inducer at the inlet. These methods require a complete redesign of the impeller structure, are complex to manufacture, and, most importantly, have poor adaptability to existing pump equipment.

[0004] Jet orifices or air inlets can be created at the impeller inlet or on the pump casing to delay vaporization by altering the local flow field. However, this method increases the complexity of the flow channel, makes it difficult to control the jet direction and pressure, and is prone to clogging over long-term operation.

[0005] High-hardness metal or ceramic coatings can improve impact resistance, but these methods only enhance the material's corrosion resistance and cannot effectively improve the localized low-pressure distribution on the blade surface. Once impeller surface strengthening is achieved, maintenance or replacement costs are high.

[0006] Rigid protrusions, guide ridges, or protective ribs are incorporated into the leading edge or inlet region of the blades to alter the local flow field distribution and increase the static pressure on the blade surface. These structures are typically implemented by attaching fixed metal or composite material components to the suction surface or leading edge of the blade, causing a flow deflection or energy distribution before the incoming flow enters the blade channel, thus delaying cavitation. While this method improves the low-pressure characteristics of the blade inlet to some extent, its inherent rigidity prevents effective deformation to absorb impact energy during bubble collapse, and the erosion load is still directly transmitted to the blade matrix, easily leading to fatigue damage and surface erosion. Furthermore, rigid structures often employ permanent connections through welding, riveting, or integral casting, making disassembly and replacement difficult and resulting in high maintenance and modification costs. More importantly, the geometric dimensions of rigid protrusions are usually large, creating significant flow disturbances and additional resistance in the mainstream region, and even inducing new separation vortices, thus adversely affecting the pump's hydraulic performance. Summary of the Invention

[0007] To address the shortcomings of existing pump blades, such as cavitation in the inlet area, difficulty in maintenance and replacement, and excessively rigid protective structures with insufficient energy absorption, this invention provides an anti-cavitation structure for pump blade inlets. By setting an embedded groove on the suction surface of the blade inlet and installing a flexible film, modular replacement and maintenance can be achieved without changing the original impeller structure. At the same time, the flexible film can undergo micro-scale deformation during the impact of bubble collapse, absorbing and dissipating impact energy and reducing stress concentration on the blade surface. The biomimetic ribs on the surface of the flexible film can also form an ordered microflow within the inlet boundary layer, reducing local negative pressure peaks and delaying the occurrence of cavitation.

[0008] The present invention achieves the above-mentioned technical objectives through the following technical means.

[0009] A cavitation-resistant structure for pump blade inlets includes a flexible film attached to the front edge region of the suction face at the blade inlet, an embedded slot for fixing the flexible film, and a sealing layer. The length of the flexible film in the radial direction is 5% to 15% of the blade chord length, and the length of the flexible film in the axial direction is 30% to 50% of the circumferential length of the impeller inlet. Several biomimetic ribs are arranged on the outer surface of the flexible film along the mainstream fluid flow direction. The height H of the biomimetic ribs is 0.05 to 0.50 mm, and the distance S between two adjacent biomimetic ribs is 0.20 to 1.00 mm.

[0010] In the above scheme, the flexible film has a double-layer composite structure, wherein the inner layer is a highly elastic support layer with an elastic modulus of 5 to 25 MPa, the outer layer is a wear-resistant and cavitation-resistant layer with an elastic modulus of 50 to 150 MPa, the surface roughness of the outer layer Ra≤0.5μm, and the inner and outer layers are bonded together by an interface coupling agent; the outer layer is provided with biomimetic ribs.

[0011] In the above scheme, the flexible film and the biomimetic ribs are integrally formed by hot pressing; the thickness of the flexible film is 0.08 to 0.50 mm, the flexible film material is polyurethane-based or polyether ether ketone-based composite, the outer layer hardness is Shore A 80 to 95, and the elongation at break is ≥100%.

[0012] In the above scheme, the angle between the main axis of the bionic rib and the main direction of the fluid flow is 0° to 10°, the depth h of the bionic rib groove is 40% to 70% of the height H of the bionic rib, and the root of the bionic rib groove is provided with a transition fillet with a width of 0.02 to 0.10 mm.

[0013] In the above scheme, the bionic ribs are continuous corrugated or discontinuous ridge-shaped and distributed along the flow direction. The cross-section of the bionic ribs is arc-shaped or semi-elliptical, and the radius of the top arc of the bionic ribs is 0.02 to 0.15 mm.

[0014] In the above scheme, the arrangement density of the bionic ribs gradually decreases from the blade inlet edge to the radially outer side, with a change rate of 1 to 3 ribs per millimeter.

[0015] In the above scheme, the flexible film is fixed by an embedded slot arranged circumferentially, the depth of the embedded slot is 0.3 to 0.8 mm, and the depth of the embedded slot is 1.2 to 1.5 times the thickness of the flexible film; the embedded slot is provided with an elastic sealant layer, which is used to form a mechanical limit and a leak-proof seal.

[0016] In the above scheme, the flexible film can be disassembled and replaced independently. The edge of the flexible film is provided with a positioning flange with a height of 0.2 to 0.5 mm, which is used to realize repeated assembly and positioning fixation.

[0017] In the above scheme, the biomimetic ribs induce microscale turbulent flow along the flow direction, the minimum static pressure in the inlet area is increased by no less than 5%, and the cavitation initiation point on the blade surface is shifted by no less than 2 mm downstream relative to the blade without the installed structure.

[0018] The above solution is applicable to the impeller inlet of centrifugal pumps, double-suction centrifugal pumps, mixed-flow pumps and axial-flow pumps. After installation, the original impeller geometry does not need to be changed, and modular anti-cavitation modification can be achieved through disassembly and assembly.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. This invention enables modular replacement and maintenance without altering the original impeller structure by setting an embedded slot on the suction surface of the blade inlet and installing a flexible film. Simultaneously, the flexible film can undergo micro-scale deformation during the impact of bubble collapse, absorbing and dissipating impact energy and reducing stress concentration on the blade surface. Furthermore, the biomimetic ribs on the surface of the flexible film can form an ordered microflow within the inlet boundary layer, reducing local negative pressure peaks and delaying the occurrence time of cavitation.

[0021] 2. The flexible film and the embedded slot of this invention are detachably connected, allowing for installation and replacement without altering the impeller's main structure; the biomimetic rib structure in this invention optimizes boundary layer flow characteristics and suppresses local low-pressure areas; the flexible material has energy-absorbing properties, effectively mitigating the impact load of bubble collapse; the embedded slot connection method ensures reliable sealing and convenient maintenance.

[0022] 3. In this invention, the flexible film adopts a double-layer composite structure, with an inner layer being a highly elastic support layer and an outer layer being a wear-resistant and cavitation-resistant layer. The inner and outer layers are bonded together by an interfacial coupling agent. This double-layer composite structure maintains the flexible energy absorption characteristics while significantly improving the surface wear resistance and cavitation resistance, making it suitable for high-lift, high-speed fluid machinery.

[0023] 4. In this invention, the distribution density of the biomimetic ribs is optimized based on the distribution law of the blade inlet pressure gradient. The gradient distribution helps to form a stable boundary laminar flow and reduce flow separation.

[0024] 5. In this invention, the biomimetic ribs can induce the fluid to form a controlled disturbance flow in the boundary layer, improve the local pressure distribution and enhance the boundary layer adhesion stability, thereby reducing the possibility of cavitation.

[0025] 6. The structure of this invention can induce the formation of an ordered disturbance flow in the boundary layer when the liquid flows, and absorb the impact energy of bubble collapse through the elastic deformation of the flexible membrane, thereby reducing the peak negative pressure at the blade inlet and delaying cavitation. It has the advantages of easy installation, strong replaceability and wide applicability. Attached Figure Description

[0026] Figure 1 A schematic diagram of a flexible biomimetic ribbed film structure installed in the inlet area of ​​a pump blade.

[0027] Figure 2 This is a schematic diagram of the biomimetic rib arrangement on the surface of a flexible thin film.

[0028] Figure 3 A partial cross-sectional view of the biomimetic ribs integrated with a flexible film;

[0029] Figure 4 This is an enlarged schematic diagram of the connection structure between the flexible film and the leading edge of the blade;

[0030] Figure 5 This is a schematic diagram of microscale flow on the surface of a biomimetic rib.

[0031] Reference numerals: 1-Flexible film; 2-Embedded slot; 3-Sealing adhesive layer; 4-Bionic rib; 5-Blade substrate. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0033] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "axial," "radial," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In this invention, unless otherwise expressly specified and limited, the terms "installed," "connected," "joined," "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0034] A cavitation-resistant structure for pump blade inlets includes a flexible film 1 attached to the front edge region of the suction face at the blade inlet, an embedded slot 2 for fixing the flexible film 1, and a sealing layer 3. The length of the flexible film 1 in the radial direction is 5% to 15% of the blade chord length, and the length of the flexible film 1 in the axial direction is 30% to 50% of the circumferential length of the impeller inlet. Several biomimetic ribs 4 are arranged on the outer surface of the flexible film 1 along the mainstream fluid flow direction. The height H of the biomimetic ribs 4 is 0.05 to 0.50 mm, and the distance S between two adjacent biomimetic ribs 4 is 0.20 to 1.00 mm.

[0035] The flexible film 1 has a double-layer composite structure, wherein the inner layer is a highly elastic support layer with an elastic modulus of 5 to 25 MPa, and the outer layer is a wear-resistant and cavitation-resistant layer with an elastic modulus of 50 to 150 MPa. The surface roughness of the outer layer Ra≤0.5 μm. The inner and outer layers are bonded together by an interfacial coupling agent. The outer layer is provided with biomimetic ribs 4.

[0036] The flexible film 1 and the biomimetic rib 4 are integrally formed by hot pressing. The thickness of the flexible film 1 is 0.08 to 0.50 mm. The material of the flexible film 1 is polyurethane-based or polyether ether ketone-based composite. The outer layer has a Shore A hardness of 80 to 95 and an elongation at break of ≥100%.

[0037] The main axis of the bionic rib 4 has an angle of 0° to 10° with the main direction of the fluid flow. The depth h of the bionic rib groove is 40% to 70% of the height H of the bionic rib 4. The root of the bionic rib groove is provided with a transition fillet with a width of 0.02 to 0.10 mm.

[0038] The bionic rib 4 is a continuous corrugated or discontinuous ridge-like shape, distributed along the flow direction. The cross-section of the bionic rib 4 is arc-shaped or semi-elliptical, and the radius of the top arc of the bionic rib 4 is 0.02 to 0.15 mm.

[0039] The arrangement density of the biomimetic ribs 4 gradually decreases from the blade inlet edge to the radially outer side, with a change rate of 1 to 3 ribs per millimeter.

[0040] The flexible film 1 is fixed by an embedded slot 2 arranged circumferentially. The depth of the embedded slot 2 is 0.3 to 0.8 mm, and the depth of the embedded slot 2 is 1.2 to 1.5 times the thickness of the flexible film 1. An elastic sealant layer 3 is provided inside the embedded slot 2. The sealant layer 3 is used to form a mechanical limit and a leak-proof seal.

[0041] The flexible film 1 can be disassembled and replaced independently. The edge of the flexible film 1 is provided with a positioning flange with a height of 0.2 to 0.5 mm, which is used to achieve repeated assembly and positioning fixation.

[0042] The biomimetic rib 4 induces microscale turbulent flow along the flow direction, increases the minimum static pressure in the inlet area by no less than 5%, and shifts the cavitation initiation point on the blade surface downstream of the blade without the structure by no less than 2 mm.

[0043] It is suitable for the impeller inlet of centrifugal pumps, double-suction centrifugal pumps, mixed-flow pumps and axial-flow pumps. After installation, there is no need to change the original impeller geometry. Modular anti-cavitation modification can be achieved through disassembly and assembly.

[0044] Figure 1This is a schematic diagram of a flexible biomimetic ribbed film structure installed in the inlet area of ​​a pump blade, which is also a preferred embodiment of the present invention. The present invention provides an anti-cavitation structure for pump blade inlets, including a flexible film 1 attached to the leading edge region of the blade inlet suction face, an embedded slot 2 for fixing the flexible film 1, and a sealing layer 3. Several biomimetic ribs 4 are arranged on the outer surface of the flexible film 1 along the mainstream fluid flow direction, and the blade substrate is 5. The flexible film 1 is tightly fitted to the leading edge of the blade inlet suction face, covering 5%–15% of the blade chord length, and distributed along the impeller inlet circumference at 30%–50%. The flexible film 1 is an arc-shaped rectangular sheet to fit the curved surface of the blade leading edge. The thickness of the flexible film 1 is 0.08–0.50 mm, and the material is polyurethane-based or polyetheretherketone-based composite, with a surface hardness Shore A of 80–95 and an elongation at break of not less than 100%. The flexible characteristics of the film allow it to produce controllable micro-deformation under the impact load of bubble collapse, thereby absorbing part of the impact energy and reducing the damage of cavitation load to the blade substrate.

[0045] Combined with appendix Figure 2 and Figure 3 As shown, the biomimetic rib 4 and the flexible film 1 are integrally formed structures, and Figure 3 This is a preferred embodiment of the invention on a centrifugal pump blade. The biomimetic rib 4 extends along the mainstream fluid direction, with the angle between the main axis of the biomimetic rib 4 and the mainstream fluid direction at the blade inlet being 0°–10°. The height H of the biomimetic rib 4 is 0.05–0.50 mm, the spacing S between adjacent biomimetic ribs is 0.20–1.00 mm, the depth h of the biomimetic rib groove is 40%–70% of the height H of the biomimetic rib 4, the groove width is 0.15–0.80 mm, and the groove bottom has a rounded transition structure with a radius of 0.03–0.08 mm. The cross-section of the biomimetic rib 4 is arc-shaped or semi-elliptical with a radius of curvature of 0.05–0.20 mm, and the surface smoothness Ra ≤ 0.20 μm. The geometry of the biomimetic rib 4 is derived from the biomimetic principle of shark skin. Its surface microribs can induce the fluid to form a controlled disturbance flow in the boundary layer, improve the local pressure distribution and enhance the boundary layer adhesion stability, thereby reducing the possibility of cavitation.

[0046] The biomimetic rib 4 is formed directly on the outer surface of the flexible film 1 using a hot-press micro-molding process. The molding temperature is 120–150℃, and the molding pressure is 0.2–0.5 MPa. After cooling and solidification, it forms an integrated structure with the flexible film 1. A transition fillet with a radius of 0.03–0.08 mm is provided at the connection between the root of the biomimetic rib 4 and the flexible film 1 to avoid stress concentration and improve fatigue life.

[0047] Combined with appendix Figure 4As shown, the edge of the flexible diaphragm 1 is embedded in the recessed slot 2 at the leading edge of the blade. The recessed slot 2 has a depth of 0.5–1.0 mm and an opening angle of 30°–45°. The recessed slot 2 is filled with a sealant layer 3 to achieve both mechanical limiting and sealing fixation. After the edge of the flexible diaphragm 1 is polished, it is inserted into the recessed slot 2, and the sealant is cured to form a detachable sealed connection structure. This installation method facilitates the maintenance and replacement of the diaphragm in the future without changing the main structure of the impeller.

[0048] Combined with appendix Figure 5 As shown, when the liquid flows along the surface of the biomimetic rib 4, a microscale turbulent flow is formed between the biomimetic rib 4 and the biomimetic groove, creating a continuous micro-vortex region. This turbulent flow can maintain a certain adhesion layer thickness within the groove, thereby improving the local static pressure level. The microfluidic structure of the fluid in the groove has a buffering and dispersing effect on the flow energy, reducing the impact energy of bubble collapse. Through structural optimization, the minimum static pressure in the blade inlet area can be increased by approximately 3%–8%, and the cavitation initiation position is shifted downstream by approximately 2 mm relative to the unstructured blade, thus significantly improving the pump's anti-cavitation performance.

[0049] In such Figure 5 In another structural form, the flexible film 1 adopts a double-layer composite structure. The inner layer is a highly elastic support layer with an elastic modulus of 5–25 MPa; the outer layer is a wear-resistant and cavitation-resistant layer with an elastic modulus of 50–150 MPa. The inner and outer layers are bonded together by an interfacial coupling agent. This double-layer composite structure maintains the flexible energy absorption characteristics while significantly improving the surface wear resistance and cavitation resistance, making it suitable for high-lift, high-speed fluid machinery.

[0050] Furthermore, the distribution density of the biomimetic ribs 4 can be optimized based on the pressure gradient distribution pattern at the blade inlet. The rib spacing in the 0–5 mm region at the blade inlet leading edge is 0.20–0.40 mm, with a relatively high density; in the radially outward region of 5–15 mm, the rib spacing gradually increases to 0.80 mm, and the density decreases by 30%–50%. This gradient distribution helps to form stable boundary laminar flow and reduce flow separation.

[0051] This invention features a highly modular structure, allowing the diaphragm to be customized according to different pump types and media characteristics. Replacement is convenient and requires no structural modifications to the impeller body. Through the combined effects of flexible energy absorption, biomimetic micro-disturbance induction, and embedded slot fixation, the cavitation resistance and service life of the pump blades can be significantly improved, demonstrating promising engineering application prospects.

[0052] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0053] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A cavitation-resistant structure for pump blade inlet, characterized in that, The device includes a flexible film (1) attached to the front edge of the blade inlet suction face, an embedded slot (2) for fixing the flexible film (1), and a sealant layer (3); the length of the flexible film (1) in the radial direction is 5% to 15% of the blade chord length, and the length of the flexible film (1) in the axial direction is 30% to 50% of the impeller inlet circumferential length; several biomimetic ribs (4) are provided on the outer surface of the flexible film (1) along the main fluid flow direction, the height H of the biomimetic ribs (4) is 0.05 to 0.50 mm, and the distance S between two adjacent biomimetic ribs (4) is 0.20 to 1.00 mm.

2. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, The flexible film (1) is a double-layer composite structure, wherein the inner layer is a high-elasticity support layer with an elastic modulus of 5 to 25 MPa, the outer layer is a wear-resistant and cavitation-resistant layer with an elastic modulus of 50 to 150 MPa, the surface roughness of the outer layer Ra≤0.5 μm, and the inner and outer layers are bonded together by an interface coupling agent; the outer layer is provided with biomimetic ribs (4).

3. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, The flexible film (1) and the biomimetic rib (4) are integrally formed by hot pressing. The thickness of the flexible film (1) is 0.08 to 0.50 mm. The material of the flexible film (1) is polyurethane-based or polyether ether ketone-based composite. The outer layer hardness is Shore A 80 to 95 and the elongation at break is ≥100%.

4. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, The main axis of the bionic rib (4) has an angle of 0° to 10° with the main direction of the fluid flow. The depth h of the bionic rib groove is 40% to 70% of the height H of the bionic rib (4). The root of the bionic rib groove is provided with a transition fillet with a width of 0.02 to 0.10 mm.

5. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, The bionic rib (4) is a continuous corrugated or discontinuous ridge line distributed along the flow direction. The cross-section of the bionic rib (4) is arc-shaped or semi-elliptical, and the radius of the top arc of the bionic rib (4) is 0.02 to 0.15 mm.

6. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, The arrangement density of the biomimetic ribs (4) gradually decreases from the blade inlet edge to the radially outer side, with a change rate of 1 to 3 ribs per millimeter.

7. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, The flexible film (1) is fixed by an embedded slot (2) arranged circumferentially. The depth of the embedded slot (2) is 0.3 to 0.8 mm and the depth of the embedded slot (2) is 1.2 to 1.5 times the thickness of the flexible film (1). An elastic sealant layer (3) is provided inside the embedded slot (2). The sealant layer (3) is used to form a mechanical limit and a leak-proof seal.

8. The anti-cavitation structure for pump blade inlet according to claim 7, characterized in that, The flexible film (1) can be disassembled and replaced independently. The edge of the flexible film (1) is provided with a positioning flange with a height of 0.2 to 0.5 mm, which is used to achieve repeated assembly and positioning fixation.

9. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, The biomimetic rib (4) induces microscale disturbance flow along the flow direction, the minimum static pressure in the inlet area is increased by no less than 5%, and the cavitation initiation point on the blade surface is pushed downstream of the blade without the structure by no less than 2 mm.

10. The anti-cavitation structure for pump blade inlet according to claim 1, characterized in that, It is suitable for the impeller inlet of centrifugal pumps, double-suction centrifugal pumps, mixed-flow pumps and axial-flow pumps. After installation, there is no need to change the original impeller geometry. Modular anti-cavitation modification can be achieved through disassembly and assembly.

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