Mixed-flow pump impeller rotatable inner shroud with bionic fine scales and design method thereof

Abstract

The application discloses a mixed delivery pump impeller rotatable inner rim with bionic fine scales, which comprises a fixed rim, and an annular groove is formed in the inner surface of the fixed rim; the cross section of the groove is T-shaped, and the groove is divided into a narrow groove part and a wide groove part; a movable rim is clamped in the groove, the movable rim comprises a rim wide part and a rim narrow part, the rim wide part is embedded in the wide groove part, and the rim narrow part is embedded in the narrow groove part; and the inner surface of the movable rim is provided with a plurality of bionic areas. The application further discloses a design method of the mixed delivery pump impeller rotatable inner rim with bionic fine scales. The mixed delivery pump impeller rotatable inner rim with bionic fine scales has the characteristics of active crushing and flow guiding of air masses, effective inhibition of gas phase coalescence, and improvement of the operation efficiency and stability of the pump.

Description

Technical Field

[0001] This invention belongs to the field of gas-liquid mixed transport fluid machinery technology, specifically relating to a rotatable inner rim of a mixed transport pump impeller with biomimetic fine scales. This invention also relates to a design method for the aforementioned rotatable inner rim of a mixed transport pump impeller with biomimetic fine scales. Background Technology

[0002] In recent years, the efficient movement of organisms in nature, such as owls, tuna, sharks, and sailfish, utilizing their unique low-resistance surface structures, has provided rich inspiration for biomimetic flow control research. Among these, the regularly arranged fine scales on shark skin have been proven to effectively suppress turbulence, mitigate flow separation, and promote the breaking up of microbubbles and vortices near the wall, thereby significantly reducing fluid resistance. In engineering biomimetic applications, to balance manufacturing processes and functional realization, the complex original shark skin scale structure is simplified into basic geometric units with similar flow control characteristics, promoting the application of biomimetic technology in various fluid machinery and engineering scenarios.

[0003] In deepwater oil and gas extraction, gas-liquid mixed-transfer pumps are critical equipment. Due to processing, assembly, and wear, unavoidable radial clearances exist between the impeller, blades, blade tips, and rim. Within this clearance region, accompanied by the mainstream complex gas-liquid two-phase flow, microbubbles are prone to collision and coalescence under high pressure differential and strong shear, potentially forming local gas films or gas clusters. These gas-phase aggregates significantly alter the flow structure within the clearance, exacerbating the instability of leakage vortices. This not only drastically reduces the pump's volumetric efficiency and pressure rise but also triggers strong unsteady pressure pulsations and rotor vibrations, seriously threatening the reliability of the unit's operation. To control leakage from complex flows (leakage vortices, leakage flow, etc.) within the blade tip clearance, existing technologies mainly focus on macroscopic geometric adjustments and passive sealing, such as optimizing clearance values ​​and using honeycomb bushings or shroud structures. However, these methods only passively alleviate leakage problems through static geometric sealing or flow channel diversion. They cannot actively intervene in the dynamically changing gas phase accumulation behavior within the gap, nor do they have the means to finely control the gas-liquid two-phase flow at the microscale of the rim wall. Therefore, they are only effective in dealing with complex and variable working conditions and cannot meet the stringent requirements of deep-water oil and gas extraction for efficient, stable, and long-cycle operation of equipment. New technical approaches are urgently needed to break through the existing limitations. Summary of the Invention

[0004] The purpose of this invention is to provide a rotating inner rim of a mixing pump impeller with biomimetic fine scales, which has the characteristics of actively breaking up and guiding the flow of air masses, effectively inhibiting gas aggregation, and improving the pump's operating efficiency and stability.

[0005] Another object of the present invention is to provide a design method for the rotatable inner rim of the impeller of the above-mentioned mixed-transport pump with biomimetic fine scales.

[0006] The technical solution adopted in this invention is a rotatable inner rim of a mixed-transfer pump impeller with biomimetic fine scales, including a fixed rim, the inner surface of which has an annular groove; the groove has a T-shaped cross-section, divided into a narrow part and a wide part; a movable rim is engaged in the groove, the movable rim including a wide part and a narrow part, the wide part of the rim being fitted into the wide part of the groove, and the narrow part of the rim being fitted into the narrow part of the groove; the inner surface of the movable rim is provided with multiple biomimetic areas.

[0007] The invention is further characterized by:

[0008] Each biomimetic zone covers the projection area of ​​the impeller blade on the inner surface of the movable rim, and extends a preset distance along the upstream direction of the fixed rim, the downstream direction of the fixed rim, the leading edge direction of the blade, and the trailing edge direction of the blade, respectively; each biomimetic zone is provided with multiple sets of biomimetic fine scale units, and each set of biomimetic fine scale units is composed of multiple biomimetic fine scale structures.

[0009] The biomimetic fine scale structure is hemispherical with a radius of r; the biomimetic fine scale structure is vertically fixed to the inner surface of the movable rim in the area.

[0010] Each biomimetic region extends 10r along the upstream and downstream directions of the fixed rim; each biomimetic region extends 5r along the leading and trailing edges of the blade; when the biomimetic region near the upstream and / or downstream of the movable rim extends less than 10r along the upstream and downstream directions of the fixed rim, it extends to the boundary of the upstream and / or downstream of the movable rim. Multiple sets of biomimetic fine scale units are arranged along the axial direction and completely cover the biomimetic area; the axial spacing between two adjacent sets of biomimetic fine scale units is equal to 5r. Inside each group of biomimetic microscale units, multiple biomimetic microscale structures are evenly arranged along the horizontal direction from the leading edge to the trailing edge of the blade. The circumferential spacing between two adjacent biomimetic microscale structures is 5r. The number of biomimetic microscale structures completely covers the impeller blade at the corresponding position.

[0011] The movable rim covers 20% to 100% of the axial length of the fixed rim along the fluid flow direction, from the upstream part to the downstream part of the fixed rim; the movable rim completely covers the fixed rim along the circumferential direction of the impeller blade, from the leading edge to the trailing edge of the blade.

[0012] The thickness of the fixed rim ranges from 10 to 50 mm, while the thickness of the movable rim ranges from 5 to 15 mm. The width of the narrow part of the groove is smaller than the width of the wide part of the rim.

[0013] Another technical solution adopted in this invention is a design method for a rotatable inner rim of a mixing pump impeller with biomimetic fine scales, comprising: Step 1: Design and construct a movable rim; Step 2: Design of a single biomimetic fine scale structure; Step 3: Establish multiple biomimetic fine scale structure arrangement rules.

[0014] Another feature of the technical solution of this invention is that: Step 1.1: The upstream section of the fixed rim is circular. Taking the dot of the circle as the origin, the z-axis points vertically to the downstream section of the fixed rim, the x-axis points horizontally to the end of the blade leading edge closest to the upstream section of the fixed rim, and the y-axis points to the trailing edge of the blade. The curved surface of the movable rim is formed by rotating a circular arc, and the equation of the circular arc is:

[0015] In the formula, These are the coordinates of the arc along the z-axis. It is the coordinate value of the arc along the x-axis. The impeller inlet diameter is The impeller outlet diameter is It represents the angle starting from the positive y-axis, ranging from 0 to 0.154π; Step 1.2: After determining the range of the movable rim on the inner surface of the fixed rim, determine the dimensions of the rim width and rim narrow section of the movable rim. The thickness of the rim narrow section is 0.1 to 0.3 times that of the rim width. An annular groove, T-shaped, is provided on the inner surface of the fixed rim, which is divided into a groove width and a groove narrow section and fits into the movable rim.

[0016] Step 2 involves the design of a single biomimetic fine-scale structure, specifically as follows: Step 2.1: In the spatial rectangular coordinate system, x o -y o Plane defines a circle P 1 P 2 P 3 P 4, P 1 P 3 is along y o The endpoints of the shaft, P 2 P 4 is along x o The endpoints of the axis are defined with the center of the circle as the origin O of the coordinate axis. o ; Step 2.2: In the spatial rectangular coordinate system, x o -z o Plane defines a semicircle P 1 P 3 P 5, P 5 is along z o The endpoints of the shaft; Step 2.3: Construct the hemispherical function equation in a spatial rectangular coordinate system to obtain a single biomimetic fine-scale structure. The hemispherical function equation is expressed as follows:

[0017] In the formula, , r Indicates the radius of the biomimetic fine phosphorus structure; Point P 1 to P The coordinate values ​​of 5 are determined as follows: point P 1 = ( x o1 , y o1 , z o1 coordinates of ) x o1 , y o1 , z o1 They are respectively:

[0018] point P 2 = ( x o2 , y o2 , z o2 coordinates of ) x o2 , y o2 , z o2 They are respectively:

[0019] point P 3 = ( x o3 , y o3 , z o3 coordinates of ) x o3 , y o3 , z o3 They are respectively:

[0020] point P 4 = ( x o4 , y o4 ,z o4 coordinates of ) x o4 , y o4 , z o4 They are respectively:

[0021] point P 5 = ( x o5 , y o5 , z o5 coordinates of ) x o5 , y o5 , z o5 They are respectively: .

[0022] Step 3, establishing the arrangement rules for multiple biomimetic fine-scale units, is performed within the spatial coordinate system established in step 1.1, and specifically includes: Step 3.1: Set multiple biomimetic areas on the inner surface of the movable rim. Each biomimetic area covers the projection area of ​​the impeller blade on the inner surface of the movable rim and extends 10r along the upstream direction and downstream direction of the fixed rim, and 5r along the leading edge direction and trailing edge direction of the blade, respectively. When the extension distance along the upstream part of the fixed rim and the downstream part of the fixed rim is less than 10r, it extends to the boundary of the upstream part and / or the downstream part of the movable rim. Step 3.2: Each group of biomimetic fine scale units is arranged sequentially along the z-axis curve in its respective biomimetic region, and the axial spacing between two adjacent groups of biomimetic fine scale units is equal to 5r; Step 3.3: Each group of biomimetic scale units arranges multiple biomimetic scale structures along the y-axis in its biomimetic area, and the circumferential spacing between two adjacent defensive scale structures is equal to 5r; Step 3.4: Taking the circular bottom point of the first biomimetic scale structure near the leading edge of the blade in each group of biomimetic scale units as the origin, denote the center point of the base of each biomimetic scale structure as... O i,j ,in i Indicates the group number. j This indicates the number of the biomimetic fine-scale structure within the group. O i,j = (x, y, z); Step 3.5: The radius of each group of biomimetic fine-scale units on the xy plane of the spatial coordinate system. for:

[0023] In the formula, The angle between the upstream portion of the movable rim and the upstream portion of the fixed rim in step 1.1; The impeller inlet diameter is The impeller outlet diameter; Step 3.6: The center point of the base of each biomimetic scale structure in the first group of biomimetic scale units. O i,j = (x1, y1, z1), where the coordinates x1, y1, and z1 are respectively:

[0024] In the formula, B is the distance between the upstream part of the movable rim and the upstream part of the fixed rim on the z-axis; The value obtained by dividing the circumferential distance of the first biomimetic fine scale structure in each group from the x-axis by 5r; Step 3.7: The center point of the base of each biomimetic scale structure in the second group of biomimetic scale units. O i,j = (x2, y2, z2), where the coordinates x2, y2, and z2 are respectively:

[0025] Step 3.8: The center point of the base of each biomimetic scale structure in the third group of biomimetic scale units. O i,j = (x3, y3, z3), where the coordinates x3, y3, and z3 are respectively:

[0026] Step 3.9: By analogy, in the formula between each group of biomimetic fine scale units, the x and y coordinates are controlled by the position of the first biomimetic fine scale structure, and the z coordinate is controlled by the number of groups, thus obtaining the arrangement rules of multiple biomimetic fine scale structures.

[0027] The beneficial effects of this invention are: This invention relates to a rotatable inner rim of a mixing pump impeller featuring biomimetic fine scales. The rim is divided into a movable rim and a fixed rim, and the excellent characteristics of shark skin scales are simplified into a regularly arranged hemispherical biomimetic structure, which is then integrated onto the surface of the movable rim. This design aims to actively intervene in the formation and coalescence of air masses through the synergistic effect of the movable rim and the biomimetic fine scale structure. The combined effect of rim rotation and the micro-protrusion structure promotes the breaking and dispersion of air masses, thereby inhibiting the formation of an air film and improving flow stability within the gap. Attached Figure Description

[0028] Figure 1This is a schematic diagram of the rotating inner rim impeller structure of the mixed-transport pump impeller with biomimetic fine scales according to the present invention. Figure 2 This is a partial structural schematic diagram of the rotatable inner rim of the impeller of the mixing pump with biomimetic fine scales according to the present invention; Figure 3 This is a schematic diagram of a single biomimetic fine scale structure on the rotatable inner rim of the mixing pump impeller of the present invention, which has biomimetic fine scales. Figure 4 This is a schematic diagram of the arrangement of the biomimetic fine scale structure on the rotatable inner rim of the mixing pump impeller of the present invention. Figure 5(a) is a streamline diagram of complex turbulent kinetic energy flow within the tip clearance of the original model in Embodiment 6 of the present invention; Figure 5(b) is a streamline diagram of complex turbulent kinetic energy flow within the blade tip gap of the rotatable inner rim of the biomimetic fine phosphorus structure in Embodiment 6 of the present invention; Figure 6 This is a comparison chart of pressure rise and efficiency in embodiments of the present invention.

[0029] In the diagram, 1 is the fixed rim; 2 is the movable rim; 3 is the impeller blade; 4 is the upstream part of the fixed rim; 5 is the downstream part of the fixed rim; 6 is the leading edge of the blade; 7 is the trailing edge of the blade; and 8 is the biomimetic area. Detailed Implementation

[0030] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0031] Example 1 This embodiment provides a rotatable inner rim of a mixing pump impeller with biomimetic fine scales, combined with... Figure 1 and Figure 2 As shown, the device includes a fixed rim 1 with an annular groove on its inner surface. The groove has a T-shaped cross-section, divided into a narrow section and a wide section. A movable rim 2 is fitted into the groove. The movable rim 2 is integrally molded and includes a wide section and a narrow section. The wide section fits into the wide section of the groove, and the narrow section fits into the narrow section of the groove, forming a T-shaped fit similar to a traditional mortise and tenon structure. The width of the narrow section of the groove is smaller than the width of the wide section of the rim. Through this T-shaped cross-section design, the movable rim 2 is engaged with the groove, allowing it to rotate bidirectionally within the groove, both clockwise and counterclockwise. This bidirectional rotation further enhances the shearing and breaking effect of the biomimetic fine-scale structure on air masses, especially in leaky vortices carrying gas. Through the synergistic effect of the rotation adjustment gap and the protruding structure, it effectively breaks up air masses, improves gas-liquid distribution, and enhances flow capacity, while maintaining structural stability and achieving adjustable gap functionality.

[0032] The fixed rim 1 includes an upstream portion 4 and a downstream portion 5 of the fixed rim; The impeller of the gas-liquid mixed transport pump includes impeller blades 3, and the impeller blades 3 include a leading edge 6 and a trailing edge 7. Multiple biomimetic areas 8 are provided on the inner surface of the movable rim 2.

[0033] Each biomimetic region 8 covers the projection area of ​​the impeller blade 3 on the inner surface of the movable rim 2, and extends a predetermined distance along the upstream part 4 of the fixed rim, the downstream part 5 of the fixed rim, the leading edge 6 of the blade, and the trailing edge 7 of the blade, respectively; each biomimetic region 8 is provided with multiple sets of biomimetic fine scale units, and each set of biomimetic fine scale units is composed of multiple biomimetic fine scale structures.

[0034] The movable rim 2 and the biomimetic region 8 with biomimetic fine scale structure designed in this embodiment achieve active breaking and flow guidance of air masses through dynamic control of the rim surface and synergistic effect of microstructure, thereby effectively inhibiting gas aggregation and improving the pump's operating efficiency and stability.

[0035] Example 2 Combination Figure 2 and Figure 3 As shown, the biomimetic fine scale structure is hemispherical with a radius of r; the biomimetic fine scale structure is vertically fixed to the inner surface of the movable rim 2 in its region. The hemispherical protrusion of a single biomimetic fine scale structure generates local micro-vortices and shearing action in the flow, which, in conjunction with the rotation of the movable rim, effectively breaks up the air mass in the blade tip gap, prevents the formation of an air film, and improves the gas-liquid two-phase flow structure.

[0036] Based on Example 1, combined with Figure 2 , Figure 4 The specific arrangement of the biomimetic fine scale structure within biomimetic zone 8 is as follows: Each bionic region 8 extends 10r along the upstream part 4 and downstream part 5 of the fixed rim, respectively; each bionic region 8 extends 5r along the leading edge 6 and trailing edge 7 of the blade, respectively; when the bionic region 8 near the upstream and / or downstream part of the movable rim 2 extends less than 10r along the upstream part 4 and downstream part 5 of the fixed rim, it extends to the boundary of the upstream and / or downstream part of the movable rim 2. Multiple sets of biomimetic fine scale units are arranged along the axial direction and completely cover the biomimetic area 8; the axial spacing between two adjacent sets of biomimetic fine scale units is equal to 5r; Inside each group of biomimetic fine scale units, multiple biomimetic fine scale structures are evenly arranged along the horizontal direction from the leading edge 6 to the trailing edge 7 of the blade. The circumferential spacing between two adjacent biomimetic fine scale structures is 5r. The number of biomimetic fine scale structures completely covers the impeller blade 3 at the corresponding position.

[0037] The biomimetic fine-scale structure designed in this invention can promote the leakage vortex in the blade tip region and the flow trajectory of the broken airflow away from the pressure surface of adjacent blades, thereby enhancing the flow capacity. The pressure rise of the gas-liquid mixed-transfer pump is significantly improved. The regular arrangement of the biomimetic fine-scale structure creates a continuous flow control region, which, combined with the rotation of the movable impeller rim, works synergistically on the air mass within the blade tip gap to achieve continuous air mass breakup and flow optimization.

[0038] Example 3 The movable rim 2 covers 20% to 100% of the axial length of the fixed rim 1 along the fluid flow direction, from the upstream portion 4 to the downstream portion 5 of the fixed rim; the movable rim 2 also achieves complete circumferential coverage of the fixed rim 1 along the circumferential direction of the impeller blade 3, from the leading edge 6 to the trailing edge 7 of the blade. The movable rim 2 has sufficient coverage area in the complex flow within the blade tip gap to actively intervene in the dynamically changing gas phase accumulation behavior within the gap.

[0039] Example 4 The thickness of the fixed rim 1 ranges from 10 to 50 mm, the thickness of the movable rim 2 ranges from 5 to 15 mm, the thickness of the leading edge 6 of the blade ranges from 2 to 5 mm, and the length of the trailing edge 7 of the blade ranges from 25 to 100 mm.

[0040] Example 5 This embodiment provides a design method for a rotatable inner rim of a mixing pump impeller with biomimetic fine scales, specifically including the following steps: Step 1: Design and construct the movable rim 2; Step 1.1: The cross-section of the upstream part 4 of the fixed rim is circular. Taking the dot of the circle as the origin, the z-axis is perpendicular to the downstream part 5 of the fixed rim, the x-axis is horizontally pointing to the end of the blade leading edge 6 closest to the upstream part 4 of the fixed rim, and the y-axis points to the direction of the blade trailing edge 7. The surface of the movable rim 2 is formed by rotating a circular arc, and the equation of the circular arc is:

[0041] In the formula, These are the coordinates of the arc along the z-axis. It is the coordinate value of the arc along the x-axis. The impeller inlet diameter is The impeller outlet diameter is It represents the angle starting from the positive y-axis, ranging from 0 to 0.154π; Step 1.2: After determining the range of the movable rim 2 on the inner surface of the fixed rim 1, determine the dimensions of the rim width and rim narrowness of the movable rim 2. The thickness of the rim narrowness is 0.1 to 0.3 times that of the rim width. An annular groove is provided on the inner surface of the fixed rim 1, which is T-shaped and divided into a groove width and a groove narrowness, and fits into the movable rim 2.

[0042] Step 2: Design of individual biomimetic fine scale structures; combined with Figure 3 Specifically, it includes: Step 2.1: In the spatial rectangular coordinate system, x o -y o Plane defines a circle P 1 P 2 P 3 P 4, P 1 P 3 is along y o The endpoints of the shaft, P 2 P 4 is along x o The endpoints of the axis are defined with the center of the circle as the origin O of the coordinate axis. o ; Step 2.2: In the spatial rectangular coordinate system, x o -z o Plane defines a semicircle P 1 P 3 P 5, P 5 is along z o The endpoints of the shaft; Step 2.3: Construct the hemispherical function equation in a spatial rectangular coordinate system to obtain a single biomimetic fine-scale structure. The hemispherical function equation is expressed as follows:

[0043] In the formula, , r This represents the radius of the biomimetic fine phosphorus structure.

[0044] Point P 1 to P The coordinate values ​​of 5 are determined as follows: point P 1 = ( x o1 , y o1 , z o1 coordinates of ) x o1 , y o1 , z o1 They are respectively:

[0045] point P 2 = ( x o2 , y o2 ,z o2 coordinates of ) x o2 , y o2 , z o2 They are respectively:

[0046] point P 3 = ( x o3 , y o3 , z o3 coordinates of ) x o3 , y o3 , z o3 They are respectively:

[0047] point P 4 = ( x o4 , y o4 , z o4 coordinates of ) x o4 , y o4 , z o4 They are respectively:

[0048] point P 5 = ( x o5 , y o5 , z o5 coordinates of ) x o5 , y o5 , z o5 They are respectively: .

[0049] Step 3: Establish multiple biomimetic fine scale structure arrangement rules.

[0050] This step is performed within the spatial coordinate system established in step 1.1, and specifically includes: Step 3.1: Multiple biomimetic areas 8 are set on the inner surface of the movable rim 2. Each biomimetic area 8 covers the projection area of ​​the impeller blade 3 on the inner surface of the movable rim 2 and extends 10r along the upstream part 4 and downstream part 5 of the fixed rim, respectively, and extends 5r along the leading edge 6 and trailing edge 7 of the blade, respectively. When the extension distance along the upstream part 4 and the downstream part 5 of the fixed rim is less than 10r, it extends to the boundary of the upstream part and / or the downstream part of the movable rim 2. Step 3.2: Each group of biomimetic fine scale units is arranged sequentially along the z-axis curve in its respective biomimetic region 8, and the axial spacing between two adjacent groups of biomimetic fine scale units is equal to 5r; Step 3.3: Each group of biomimetic scale units arranges multiple biomimetic scale structures along the y-axis in its biomimetic area 8, and the circumferential spacing between two adjacent defensive scale structures is equal to 5r; Step 3.4: Taking the circular point on the bottom surface of the first biomimetic scale structure closest to the leading edge 6 of the blade in each group of biomimetic scale units as the origin, denote the center point of the base of each biomimetic scale structure as... O i,j ,in i Indicates the group number. j This indicates the number of the biomimetic fine-scale structure within the group. O i,j = (x, y, z); Step 3.5: The radius of each group of biomimetic fine-scale units on the xy plane of the spatial coordinate system. for:

[0051] In the formula, The angle between the upstream portion of the movable rim and the upstream portion of the fixed rim in step 1.1; The impeller inlet diameter is The impeller outlet diameter; Step 3.6: The center point of the base of each biomimetic scale structure in the first group of biomimetic scale units. O i,j = (x1, y1, z1), where the coordinates x1, y1, and z1 are respectively:

[0052] In the formula, B is the distance between the upstream part of the movable rim and the upstream part of the fixed rim on the z-axis; The value obtained by dividing the circumferential distance of the first biomimetic fine scale structure in each group from the x-axis by 5r; Step 3.7: The center point of the base of each biomimetic scale structure in the second group of biomimetic scale units. O i,j= (x2, y2, z2), where the coordinates x2, y2, and z2 are respectively:

[0053] Step 3.8: The center point of the base of each biomimetic scale structure in the third group of biomimetic scale units. O i,j = (x3, y3, z3), where the coordinates x3, y3, and z3 are respectively:

[0054] Step 3.9: By analogy, in the formula between each group of biomimetic fine scale units, the x and y coordinates are controlled by the position of the first biomimetic fine scale structure, and the z coordinate is controlled by the number of groups, thus obtaining the arrangement rules of multiple biomimetic fine scale structures.

[0055] In the description of this invention, it should be understood that the term "three groups" is exemplary and should not be construed as a limitation of the invention. The number of groups in the biomimetic fine scale structure varies with the geometric parameters.

[0056] Example 6 This embodiment uses numerical calculations to verify the optimization of complex flow within the impeller tip clearance of the pump by the movable rim of the biomimetic fine scale structure. By comparing the pump performance differences before and after optimization, the correlation between the movable rim of the biomimetic fine scale structure and performance improvement is found.

[0057] Design one set of working conditions: The optimal efficiency point (Q) is selected at a speed of 1500 rpm under the flow condition. BEP ) operating condition, where Q BEP The operating flow rate corresponding to the optimal efficiency point; After selecting the surge condition as the inlet gas content operating condition, the corresponding inlet gas content is IGVF=15%, where IGVF is the inlet gas content. The specific operating condition is: the optimal efficiency point flow rate Q. BEP =33m 3 / h, inlet gas content IGVF=15%.

[0058] Figures 5(a) and 5(b) show schematic diagrams of the complex turbulent kinetic energy streamlines within the gap between the front and rear blade tips of the original model (a gas-liquid mixing pump without moving rims and biomimetic fine scale structure) and the structure of the present invention, respectively. Compared with the original model, the biomimetic fine scale structure generates high turbulent kinetic energy, produces stagnant vortices in the gap, reduces fluid loss, and improves the distribution of air masses. Figure 6 The pressure rise and efficiency of the front and rear gas-liquid mixing pumps were demonstrated.

[0059] The biomimetic fine-scale structure of the movable rim improves the pump's pressure rise and efficiency while reducing the gas volume fraction within the guide vanes. The biomimetic fine-scale structure pump shows a significant improvement in pressure rise and efficiency, increasing by 6.9% and 5.3% respectively compared to the original values, demonstrating a substantial performance enhancement.

Claims

1. A rotatable inner rim of a mixing pump impeller with biomimetic fine scales, characterized in that, It includes a fixed rim (1), the inner surface of which is provided with an annular groove; the groove has a T-shaped cross section, which is divided into a narrow part and a wide part; a movable rim (2) is engaged in the groove, the movable rim (2) includes a wide part and a narrow part, the wide part of the rim is engaged in the wide part of the groove, and the narrow part of the rim is engaged in the narrow part of the groove; the inner surface of the movable rim (2) is provided with multiple biomimetic areas (8).

2. The rotatable inner rim of the mixing pump impeller with biomimetic fine scales according to claim 1, characterized in that, Each of the biomimetic regions (8) covers the projection area of ​​the impeller blade (3) on the inner surface of the movable rim (2), and extends a predetermined distance along the upstream (4) direction of the fixed rim, the downstream (5) direction of the fixed rim, the leading edge (6) direction of the blade, and the trailing edge (7) direction of the blade, respectively; each of the biomimetic regions (8) is provided with multiple sets of biomimetic fine scale units, and each set of biomimetic fine scale units is composed of multiple biomimetic fine scale structures.

3. The rotatable inner rim of the mixing pump impeller with biomimetic fine scales according to claim 2, characterized in that, The biomimetic fine scale structure is hemispherical with a radius of r; the biomimetic fine scale structure is vertically fixed to the inner surface of the movable rim (2) in the area.

4. The rotatable inner rim of the mixing pump impeller with biomimetic fine scales according to claim 3, characterized in that, Each of the bionic regions (8) extends 10r along the upstream (4) and downstream (5) directions of the fixed rim; each of the bionic regions (8) extends 5r along the leading edge (6) and trailing edge (7) directions of the blade; when the bionic regions (8) near the upstream and / or downstream of the movable rim (2) extend less than 10r along the upstream (4) and downstream (5) directions of the fixed rim, they extend to the boundaries of the upstream and / or downstream of the movable rim (2); Multiple sets of the biomimetic fine scale units are arranged along the axial direction and completely cover the biomimetic area (8); the axial spacing between two adjacent sets of biomimetic fine scale units is equal to 5r; Inside each group of biomimetic microscale units, multiple biomimetic microscale structures are evenly arranged along the horizontal direction from the leading edge (6) to the trailing edge (7) of the blade. The circumferential spacing between two adjacent biomimetic microscale structures is 5r. The number of biomimetic microscale structures completely covers the impeller blade (3) at the corresponding position.

5. The rotatable inner rim of the mixing pump impeller with biomimetic fine scales according to claim 1, characterized in that, The movable rim (2) covers 20% to 100% of the axial length of the fixed rim (1) from the upstream part (4) to the downstream part (5) of the fixed rim along the fluid flow direction; the movable rim (2) completely covers the fixed rim (1) along the circumferential direction of the impeller blade (3) from the leading edge (6) to the trailing edge (7).

6. The rotatable inner rim of the mixing pump impeller with biomimetic fine scales according to claim 1, characterized in that, The thickness of the fixed rim (1) ranges from 10 to 50 mm, and the thickness of the movable rim (2) ranges from 5 to 15 mm. The width of the narrow part of the groove is less than the width of the wide part of the rim.

7. A design method for a rotatable inner rim of a mixed-transport pump impeller with biomimetic fine scales, used to design the rotatable inner rim of a mixed-transport pump impeller with biomimetic fine scales as described in any one of claims 1 to 6, characterized in that, include: Step 1: Design and construct a movable rim (2); Step 2: Design of a single biomimetic fine scale structure; Step 3: Establish multiple biomimetic fine scale structure arrangement rules.

8. The design method for the rotatable inner rim of the impeller of the mixed-transport pump with biomimetic fine scales according to claim 7, characterized in that, Step 1 specifically includes: Step 1.1: The cross-section of the upstream part (4) of the fixed rim is circular. The origin is the circle. The z-axis is perpendicular to the downstream part (5) of the fixed rim. The x-axis is the end closest to the leading edge (6) of the blade. The y-axis points to the trailing edge (7) of the blade. The surface of the movable rim (2) is formed by rotating a circular arc, and the equation of the circular arc is: In the formula, These are the coordinates of the arc along the z-axis. It is the coordinate value of the arc along the x-axis. The impeller inlet diameter is The impeller outlet diameter is It represents the angle starting from the positive y-axis, ranging from 0 to 0.154π; Step 1.2: After determining the range of the movable rim (2) on the inner surface of the fixed rim (1), determine the dimensions of the rim width and rim narrow of the movable rim (2). The thickness of the rim narrow is 0.1 to 0.3 times that of the rim width. An annular groove is provided on the inner surface of the fixed rim (1), which is T-shaped and divided into a groove width and a groove narrow, and fits into the movable rim (2).

9. The design method for the rotatable inner rim of the impeller of the mixed-transport pump with biomimetic fine scales according to claim 8, characterized in that, Step 2 involves the design of a single biomimetic fine-scale structure, specifically as follows: Step 2.1: In the spatial rectangular coordinate system, x o -y o Plane defines a circle P 1 P 2 P 3 P 4, P 1 P 3 is along y o The endpoints of the shaft, P 2 P 4 is along x o The endpoints of the axis are defined with the center of the circle as the origin O of the coordinate axis. o ; Step 2.2: In the spatial rectangular coordinate system, x o -z o Plane defines a semicircle P 1 P 3 P 5, P 5 is along z o The endpoints of the shaft; Step 2.3: Construct the hemispherical function equation in a spatial rectangular coordinate system to obtain a single biomimetic fine-scale structure. The hemispherical function equation is expressed as follows: In the formula, , r Indicates the radius of the biomimetic fine phosphorus structure; Point P 1 to P The coordinate values ​​of 5 are determined as follows: point P 1 = ( x o1 , y o1 , z o1 coordinates of ) x o1 , y o1 , z o1 They are respectively: point P 2 = ( x o2 , y o2 , z o2 coordinates of ) x o2 , y o2 , z o2 They are respectively: point P 3 = ( x o3 , y o3 , z o3 coordinates of ) x o3 , y o3 , z o3 They are respectively: point P 4 = ( x o4 , y o4 , z o4 coordinates of ) x o4 , y o4 , z o4 They are respectively: point P 5 = ( x o5 , y o5 , z o5 coordinates of ) x o5 , y o5 , z o5 They are respectively: 。 10. The design method for the rotatable inner rim of the impeller of the mixed-transport pump with biomimetic fine scales according to claim 9, characterized in that, Step 3, establishing the arrangement rules for multiple biomimetic fine-scale units, is performed within the spatial coordinate system established in step 1.1, and specifically includes: Step 3.1: Multiple biomimetic areas (8) are provided on the inner surface of the movable rim (2). Each biomimetic area (8) covers the projection area of ​​the impeller blade (3) on the inner surface of the movable rim (2) and extends 10r along the upstream (4) direction and the downstream (5) direction of the fixed rim, respectively, and extends 5r along the leading edge (6) direction and the trailing edge (7) direction of the blade, respectively. When the extension distance along the upstream part (4) and the downstream part (5) of the fixed rim is less than 10r, it extends to the boundary of the upstream part and / or the downstream part of the movable rim (2); Step 3.2: Each group of biomimetic fine scale units is arranged sequentially along the z-axis curve in its respective biomimetic region (8), and the axial spacing between two adjacent groups of biomimetic fine scale units is equal to 5r; Step 3.3: Each group of biomimetic scale units arranges multiple biomimetic scale structures along the y-axis in its biomimetic area (8), and the circumferential spacing between two adjacent defensive scale structures is equal to 5r; Step 3.4: Taking the circular bottom point of the first biomimetic scale structure near the leading edge (6) of the blade in each group of biomimetic scale units as the origin, record the center point of the base of each biomimetic scale structure as... O i,j ,in i Indicates the group number. j This indicates the numbering of the biomimetic fine-scale structure within the group. O i,j = (x, y, z); Step 3.5: The radius of each group of biomimetic fine-scale units on the xy plane of the spatial coordinate system. for: In the formula, The angle between the upstream portion of the movable rim and the upstream portion of the fixed rim in step 1.1; The impeller inlet diameter is The impeller outlet diameter; Step 3.6: The center point of the base of each biomimetic scale structure in the first group of biomimetic scale units. O i,j = (x1, y1, z1), where the coordinates x1, y1, and z1 are respectively: In the formula, B is the distance between the upstream part of the movable rim and the upstream part of the fixed rim on the z-axis; The value obtained by dividing the circumferential distance of the first biomimetic fine scale structure in each group from the x-axis by 5r; Step 3.7: The center point of the base of each biomimetic scale structure in the second group of biomimetic scale units. O i,j = (x2, y2, z2), where the coordinates x2, y2, and z2 are respectively: Step 3.8: The center point of the base of each biomimetic scale structure in the third group of biomimetic scale units. O i,j = (x3, y3, z3), where the coordinates x3, y3, and z3 are respectively: Step 3.9: By analogy, in the formula between each group of biomimetic fine scale units, the x and y coordinates are controlled by the position of the first biomimetic fine scale structure, and the z coordinate is controlled by the number of groups, thus obtaining the arrangement rules of multiple biomimetic fine scale structures.

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