A small hydroelectric power plant for a pipeline
By optimizing the guide vane and hub structure and improving the flow channel design, the problems of poor adaptability and low efficiency of existing pipeline hydropower generation devices have been solved, achieving efficient and stable operation and reducing costs over a wide flow range.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG SCI-TECH UNIV
- Filing Date
- 2026-04-13
- Publication Date
- 2026-06-12
AI Technical Summary
Existing pipeline hydroelectric power generation devices have poor adaptability, low efficiency and instability. They are difficult to start up, especially under low flow conditions, and are costly. They are also susceptible to the effects of silt and impurities, and their sealing structures are prone to leakage, making maintenance difficult.
It adopts a multi-guide vane impeller alternating series structure. The guide vane is designed to consist of an inner ring, an outer ring and a middle ring. The middle ring of the guide vane forms a specific angle with the main shaft. The inner guide vane is equipped with a quadrilateral through hole. A pressure boosting hole is added to the hub. The arc-shaped protrusion design improves the flow and optimizes the flow channel structure.
It improves the adaptability and efficiency of hydropower generation equipment, expands the stable operating range, reduces eddies and vibrations, lowers costs, enhances cavitation resistance, and ensures stable power generation under low flow conditions.
Smart Images
Figure CN122190969A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of fluid machinery technology, specifically to a power generation device, and more specifically to a small hydroelectric power generation device for pipelines. Background Technology
[0002] The core advantage of pipeline hydropower lies in "turning waste into treasure," converting the excess pressure or kinetic energy of fluids within the pipeline into electrical energy—a highly efficient method of energy cascade utilization. First, it generates significant economic benefits; the generated electricity can be directly used for monitoring and communication equipment along the pipeline or fed into the power grid, achieving "zero-cost" power generation and reducing operating expenses. Second, it offers outstanding environmental benefits; the power generation process does not consume fossil fuels and has no carbon emissions, making it a typical clean energy source. Finally, it optimizes system operation; while generating electricity, it can replace traditional pressure reducing valves, precisely controlling pipeline pressure, reducing equipment wear and noise pollution, and achieving the dual functions of energy saving and regulation.
[0003] The prior art CN 220769615U discloses a self-balancing power generation device for water pipelines. By setting up a thrust disc to drive the bearing to move back and forth, the force on the impeller under the forward water flow is the same as the reverse force of the water flow on the thrust disc within the cavity. This ensures that the thrust bearing is in a state of force balance during operation, preventing it from being biased to one side due to water flow impact, which would increase friction and affect power generation. Furthermore, the bearing is water-lubricated, eliminating friction in the mechanical components of the thrust bearing, significantly extending its service life and reducing maintenance costs.
[0004] The main shortcomings of the current technology lie in its adaptability, economy, and reliability. First, its adaptability is poor; the drastic and variable fluctuations in flow and pressure within the pipeline cause the micro-hydropower generator to frequently deviate from its high-efficiency range, resulting in low and unstable power generation efficiency, especially under low flow velocity conditions (e.g., <0.5 m / s), where it may even fail to start. Second, economic bottlenecks are significant; miniaturized equipment requires high manufacturing precision to maintain efficiency, leading to high costs and long investment payback periods. Finally, reliability is a concern; silt and impurities can cause impeller wear and blockage, and the complex sealing structure is prone to leakage under high pressure, increasing the difficulty of equipment maintenance and the safety risks of pipeline operation.
[0005] There is an urgent and important practical necessity to improve the hydropower generation technology in pipelines. Therefore, in response to these problems, the inventors propose a small-scale hydropower generation device for pipelines, which optimizes the hydraulic design from the perspectives of guide vanes, impellers, and other structures, solving the problems of poor adaptability and low efficiency of existing equipment, significantly improving its economic efficiency, and optimizing system operation. Summary of the Invention
[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a small-scale hydroelectric power generation device for pipelines.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] A small hydroelectric power generation device for pipelines includes a casing, an inlet guide cone, an inlet bearing, guide vanes, an impeller, a coil, a rotor, an outlet bearing, a thrust disk, an outlet guide cone, and a main shaft. The main shaft is disposed within the casing, and along the flow path, the inlet guide cone, guide vanes, impeller, and outlet guide cone are sequentially arranged on the main shaft. The power generation device adopts a multi-guide vane and impeller alternating series structure, including a first guide vane, a first impeller, a second guide vane, a second impeller, a third guide vane, a third impeller, and an outlet guide vane connected in sequence. The inlet bearing is disposed within the first guide vane, the outlet bearing is disposed within the outlet guide vane, and the thrust disk is mounted on one end of the outlet bearing. The impeller includes a hub and blades. A rotor is fixed to the outer ring of the blades, and a coil is provided on the inner wall of the housing corresponding to the rotor position. The impeller is characterized by the following features: each guide vane includes an inner guide vane ring, an inner guide vane, a middle guide vane ring, an outer guide vane, and an outer guide vane ring connected sequentially from the radial inside to the outside. The inner guide vane ring is fixed to the main shaft. The inner guide vane is a cylindrical blade, and the outer guide vane is a twisted blade. The outer guide vane ring is fixed to the inner wall of the housing. The axial cross-sectional centerline of the middle guide vane ring forms an angle A with the centerline of the main shaft, where 0° < A ≤ 30°. The inner guide vane has a through hole with an axial projection of a quadrilateral structure along its axial direction. An arc-shaped protrusion is provided at the connection between the outer guide vane and the middle guide vane ring.
[0009] Furthermore, the center line of the axial section of the middle ring of the first guide vane is at an angle A1 to the center line of the main shaft, the center line of the axial section of the middle ring of the second guide vane 42 is at an angle A2 to the center line of the main shaft, the center line of the axial section of the middle ring of the third guide vane is at an angle A3 to the center line of the main shaft, and the center line of the axial section of the middle ring of the outlet guide vane is at an angle A4 to the center line of the main shaft, wherein A1 > A2 > A3, and A4 > 1.2A3.
[0010] Furthermore, A1 = 25°~30°, A2 = 18°~23°, A3 = 8°~12°, and A4 = 10°~16°.
[0011] Furthermore, the through hole is located on the side closer to the middle ring of the guide vane.
[0012] Furthermore, the quadrilateral structure can be rectangular, rhomboid, or trapezoidal.
[0013] Furthermore, the curved, raised outline is part of the Archimedean spiral.
[0014] Furthermore, the radial length of the outer guide vane is L1, and the radial length of the inner guide vane is L2, with L1:L2 = 1.2 to 2.5.
[0015] Furthermore, the hub protrudes radially from the inner ring of the guide vane, and the protruding portion is provided with a through pressure boosting hole.
[0016] Furthermore, the diameter of the pressure boosting orifice is D, where D = 0.1 to 0.3 L2.
[0017] Furthermore, the flow direction of the pressure boosting orifice is consistent with the direction of the blade root.
[0018] Furthermore, the flow channel profile of the pressure boosting orifice is "S" shaped.
[0019] Furthermore, the number of pressure-boosting holes is less than the number of blades.
[0020] Compared with the prior art, the present invention has the following advantages:
[0021] 1. The power generation unit adopts a multi-guide vane impeller alternating series structure, including a first guide vane, a first impeller, a second guide vane, a second impeller, a third guide vane, a third impeller, and an outlet guide vane connected in sequence. The inlet bearing is located inside the first guide vane, and the outlet bearing is located inside the outlet guide vane. The thrust disk is installed at one end of the outlet bearing. The impeller includes a hub and blades. A rotor is fixed to the outer ring of the blades, and a coil is provided on the inner wall of the housing corresponding to the rotor position. Each guide vane includes an inner guide vane ring, an inner guide vane, a middle guide vane ring, an outer guide vane, and an outer guide vane ring connected in sequence from the radial inside to the outside. The inner guide vane ring is fixed on the main shaft, and the inner guide vane is... The blades are cylindrical, with the outer guide vane being a twisted blade. The outer ring of the guide vane is fixed to the inner wall of the casing. The axial cross-section centerline of the middle ring of the guide vane forms an angle A with the centerline of the main shaft, where 0° < A ≤ 30°. The angle between the axial cross-section centerline of the middle ring of the first guide vane and the centerline of the main shaft is A1; the angle between the axial cross-section centerline of the middle ring of the second guide vane and the centerline of the main shaft is A2; the angle between the axial cross-section centerline of the middle ring of the third guide vane and the centerline of the main shaft is A3; and the angle between the axial cross-section centerline of the middle ring of the outlet guide vane and the centerline of the main shaft is A4, where A1 > A2 > A3, and A4 > 1.2A3. A1 = 25°~30°, A2 = 18°~23°, A3 = 8°~12°, and A4 = 10°~16°. The radial length of the outer guide vane is L1, and the radial length of the inner guide vane is L2, where L1:L2 = 1.2~2.5. The tilt angle of the guide vane ring can guide and rectify the fluid, allowing the water flow to enter the next stage flow channel more smoothly, suppressing backflow and pre-swirl, improving anti-cavitation performance, and guiding the fluid to gradually decelerate and diffuse, thereby reducing the impact loss caused by abrupt changes in the flow channel and improving the hydraulic efficiency of the hydroelectric power generation device.
[0022] 2. The inner guide vane has a through-hole with an axial projection of a quadrilateral structure, located closer to the middle ring of the guide vane. The quadrilateral structure can be rectangular, rhomboid, or trapezoidal. This hole arrangement results in a more uniform flow velocity distribution, reduces turbulence intensity, and thus minimizes eddies and flow separation. This effectively improves the suction performance of the hydroelectric power generation unit, expands its stable operating range, enhances its cavitation resistance, and prevents vibration and noise caused by cavitation.
[0023] 3. The outline of the arc-shaped protrusion is part of an Archimedean spiral. During low-flow operation, stall vortices and backflow are easily generated between the impeller and guide vanes. The arc-shaped protrusion guides the fluid, effectively reducing the intensity and size of these vortices, making the flow within the impeller more stable. By improving the angle of the water flow entering the guide vanes, the protrusion design reduces the impeller outlet flow angle, directly increasing the hump margin and ensuring stable head even under low-flow conditions, preventing severe unit vibration caused by sudden head drops.
[0024] 4. The hub protrudes radially from the inner ring of the guide vanes, with a through-hole for pressure boosting. The diameter of the pressure boosting hole is D, where D = 0.1–0.3 L². The flow channel direction of the pressure boosting hole is consistent with the blade root direction. The flow channel outline of the pressure boosting hole is S-shaped. The number of pressure boosting holes is less than the number of blades. Besides its core mechanical function of balancing axial forces, the flow channel holes on the impeller hub also further improve fluid characteristics. This transforms the simple pressure relief hole into a flow guiding structure that actively improves the flow field, adjusting the area and structure of the flow channel, thereby optimizing the impeller's high-efficiency range and enabling the hydroelectric power generation device to maintain high efficiency and operational stability over a wider flow range. Attached Figure Description
[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0026] Figure 1 This is a schematic diagram of the structure of the small hydroelectric power generation device for pipelines according to the present invention;
[0027] Figure 2 This is a schematic diagram of the relative structure of the guide vane and impeller of the present invention;
[0028] Figure 3 This is a schematic diagram of the guide vane structure of the present invention;
[0029] Figure 4 This is a schematic diagram of the impeller structure of the present invention.
[0030] The reference numerals in the above figures are as follows: 1. Housing; 2. Inlet guide cone; 3. Inlet bearing; 4. Guide vane; 5. Impeller; 6. Coil; 7. Rotor; 8. Outlet bearing; 9. Thrust disc; 10. Outlet guide cone; 11. Main shaft; 41. First guide vane; 531. First impeller; 42. Second guide vane; 532. Third guide vane; 43. Third impeller; 533. Outlet guide vane; 44. Hub; 51. Blade; 50. Pressure boosting hole; 52. Inner ring of guide vane; 401. Inner guide vane; 402. Middle ring of guide vane; 403. Outer guide vane; 404. Outer ring of guide vane; 405. Through hole; 406. Arc-shaped protrusion; 407. Axial section of middle ring of guide vane 403. Angle A between the centerline of the surface and the centerline of the main shaft 11; angle A1 between the centerline of the axial section of the guide ring 403 of the first guide vane 41 and the centerline of the main shaft 11; angle A2 between the centerline of the axial section of the guide ring 403 of the second guide vane 42 and the centerline of the main shaft 11; angle A3 between the centerline of the axial section of the guide ring 403 of the third guide vane 43 and the centerline of the main shaft 11; angle A4 between the centerline of the axial section of the guide ring 403 of the outlet guide vane 44 and the centerline of the main shaft 11; radial length L1 of the outer guide vane 404; radial length L2 of the inner guide vane 402; and diameter D of the pressure boosting hole 52. Detailed Implementation
[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0032] The present invention will now be described in further detail with reference to the accompanying drawings.
[0033] like Figure 1-4As shown, a small hydroelectric power generation device for pipelines includes a housing 1, an inlet guide cone 2, an inlet bearing 3, a guide vane 4, an impeller 5, a coil 6, a rotor 7, an outlet bearing 8, a thrust disk 9, an outlet guide cone 10, and a main shaft 11. The main shaft 11 is disposed inside the housing 1, and along the flow path direction, the inlet guide cone 2, guide vane 4, impeller 5, and outlet guide cone 10 are sequentially arranged on the main shaft 11. The power generation device adopts a multi-guide vane and impeller alternating series structure, including a first guide vane 41, a first impeller 531, a second guide vane 42, a second impeller 532, a third guide vane 43, a third impeller 533, and an outlet guide vane 44 connected in sequence. The inlet bearing 3 is disposed inside the first guide vane 41, the outlet bearing 8 is disposed inside the outlet guide vane 44, the thrust disk 9 is installed at one end of the outlet bearing 8, and the impeller 5 is enclosed in a coil. The device includes a hub 51 and blades 50. A rotor 7 is fixed to the outer ring of the blades 50, and a coil 6 is provided on the inner wall of the housing 1 corresponding to the position of the rotor 7. The device is characterized in that: each guide vane 4 includes an inner guide vane ring 401, an inner guide vane 402, a middle guide vane ring 403, an outer guide vane 404, and an outer guide vane ring 405 connected in sequence from the radial inside to the outside. The inner guide vane ring 401 is fixed on the main shaft 11. The inner guide vane 402 is a cylindrical blade, and the outer guide vane 404 is a bent and twisted blade. The outer guide vane ring 405 is fixed on the inner wall of the housing 1. The center line of the axial section of the middle guide vane ring 403 has an angle A with the center line of the main shaft 11, where 0° < A ≤ 30°. The inner guide vane 402 is provided with a through hole 406 with an axial projection quadrilateral structure. An arc-shaped protrusion 407 is provided at the connection between the outer guide vane 404 and the middle guide vane ring 403.
[0034] Furthermore, the center line of the axial section of the middle ring 403 of the first guide vane 41 is at an angle A1 to the center line of the main shaft 11, the center line of the axial section of the middle ring 403 of the second guide vane 42 is at an angle A2 to the center line of the main shaft 11, the center line of the axial section of the middle ring 403 of the third guide vane 43 is at an angle A3 to the center line of the main shaft 11, and the center line of the axial section of the middle ring 403 of the outlet guide vane 44 is at an angle A4 to the center line of the main shaft 11, wherein A1 > A2 > A3, and A4 > 1.2A3.
[0035] Furthermore, A1 = 25°~30°, A2 = 18°~23°, A3 = 8°~12°, and A4 = 10°~16°.
[0036] Furthermore, the through hole 406 is located on the side closer to the guide vane middle ring 403.
[0037] Furthermore, the quadrilateral structure can be rectangular, rhomboid, or trapezoidal.
[0038] Furthermore, the outline of the arcuate protrusion 407 is part of the Archimedean spiral.
[0039] Furthermore, the radial length of the outer guide vane 404 is L1, and the radial length of the inner guide vane 402 is L2, with L1:L2 = 1.2 to 2.5.
[0040] Furthermore, the hub 51 protrudes radially from the inner ring 401 of the guide vane, wherein the protruding portion is provided with a through pressure boosting hole 52.
[0041] Furthermore, the diameter of the pressure boosting hole 52 is D, where D = 0.1 to 0.3 L2.
[0042] Furthermore, the flow direction of the pressure boosting hole 52 is consistent with the direction of the blade root of the blade 50.
[0043] Furthermore, the flow channel profile of the pressure boosting orifice 52 is "S" shaped.
[0044] Furthermore, the number of pressure-boosting holes 52 is less than the number of blades in blade 50.
[0045] The power generation unit adopts a multi-guide vane impeller alternating series structure, including a first guide vane, a first impeller, a second guide vane, a second impeller, a third guide vane, a third impeller, and an outlet guide vane connected in sequence. An inlet bearing is located inside the first guide vane, and an outlet bearing is located inside the outlet guide vane. A thrust disk is installed at one end of the outlet bearing. The impeller includes a hub and blades, with a rotor fixed to the outer ring of the blades. A coil is installed on the inner wall of the housing corresponding to the rotor position. Each guide vane includes an inner guide vane ring, an inner guide vane, a middle guide vane ring, an outer guide vane, and an outer guide vane ring connected in sequence from the radially inner side to the outer side. The inner guide vane ring is fixed to the main shaft, and the inner guide vane is... The blades are cylindrical, with the outer guide vane being a twisted blade. The outer ring of the guide vane is fixed to the inner wall of the casing. The axial cross-section centerline of the middle ring of the guide vane forms an angle A with the centerline of the main shaft, where 0° < A ≤ 30°. The angle between the axial cross-section centerline of the middle ring of the first guide vane and the centerline of the main shaft is A1; the angle between the axial cross-section centerline of the middle ring of the second guide vane and the centerline of the main shaft is A2; the angle between the axial cross-section centerline of the middle ring of the third guide vane and the centerline of the main shaft is A3; and the angle between the axial cross-section centerline of the middle ring of the outlet guide vane and the centerline of the main shaft is A4, where A1 > A2 > A3, and A4 > 1.2A3. A1 = 25°~30°, A2 = 18°~23°, A3 = 8°~12°, and A4 = 10°~16°. The radial length of the outer guide vane is L1, and the radial length of the inner guide vane is L2, where L1:L2 = 1.2~2.5. The tilt angle of the guide vane ring can guide and rectify the fluid, allowing the water flow to enter the next stage flow channel more smoothly, suppressing backflow and pre-swirl, improving anti-cavitation performance, and guiding the fluid to gradually decelerate and diffuse, thereby reducing the impact loss caused by abrupt changes in the flow channel and improving the hydraulic efficiency of the hydroelectric power generation device.
[0046] The inner guide vane features a through-hole with an axially projected quadrilateral structure, located closer to the middle ring of the guide vane. The quadrilateral structure can be rectangular, rhomboid, or trapezoidal. This design results in a more uniform flow velocity distribution, reduces turbulence intensity, and consequently minimizes eddies and flow separation. This effectively improves the suction performance of the hydroelectric power generation unit, expands its stable operating range, enhances its cavitation resistance, and prevents vibration and noise caused by cavitation.
[0047] The outline of the arc-shaped protrusion is part of an Archimedean spiral. During low-flow operation, stall vortices and backflow are easily generated between the impeller and guide vanes. The arc-shaped protrusion guides the fluid, effectively reducing the intensity and size of these vortices, making the flow within the impeller more stable. By improving the angle of the water flow entering the guide vanes, the protrusion design reduces the impeller outlet flow angle, directly increasing the hump margin and ensuring stable head even under low-flow conditions, preventing severe unit vibration caused by sudden head drops.
[0048] The impeller hub protrudes radially from the inner ring of the guide vanes, and the protruding portion contains through-holes for pressure boosting. The diameter of the pressure boosting hole is D, where D = 0.1–0.3 L². The flow channel direction of the pressure boosting hole is consistent with the blade root direction. The flow channel outline of the pressure boosting hole is S-shaped. The number of pressure boosting holes is less than the number of blades. Besides its core mechanical function of balancing axial forces, the flow channel holes on the impeller hub also further improve fluid characteristics. This transforms the impeller from a simple pressure relief hole into a flow guiding structure that actively improves the flow field, adjusting the area and structure of the flow channel, thereby optimizing the impeller's high-efficiency range and enabling the hydroelectric power generation device to maintain high efficiency and operational stability over a wider flow range.
[0049] The above embodiments are illustrative of the present invention and not intended to limit the invention. It is understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.
Claims
1. A small hydroelectric power generation device for pipelines, comprising a housing (1), an inlet guide cone (2), an inlet bearing (3), a guide vane (4), an impeller (5), a coil (6), a rotor (7), an outlet bearing (8), a thrust disc (9), an outlet guide cone (10), and a main shaft (11); the main shaft (11) is disposed inside the housing (1), and along the flow path direction, the inlet guide cone (2), the guide vane (4), the impeller (5), and the outlet guide cone (10) are sequentially disposed on the main shaft (11); wherein the power generation device adopts a multi-guide vane impeller alternating series structure, including a first... The impeller comprises a guide vane (41), a first impeller (531), a second guide vane (42), a second impeller (532), a third guide vane (43), a third impeller (533), and an outlet guide vane (44). An inlet bearing (3) is disposed within the first guide vane (41), and an outlet bearing (8) is disposed within the outlet guide vane (44). A thrust disk (9) is mounted on one end of the outlet bearing (8). The impeller (5) includes a hub (51) and blades (50). A rotor (7) is fixed to the outer ring of the blades (50). A coil (6) is disposed on the inner wall of the housing (1) corresponding to the position of the rotor (7). The impeller is characterized by: Each guide vane (4) includes an inner guide vane ring (401), an inner guide vane (402), a middle guide vane ring (403), an outer guide vane (404), and an outer guide vane ring (405) connected in sequence from the radial inside to the outside. The inner guide vane ring (401) is fixed on the main shaft (11). The inner guide vane (402) is a cylindrical blade, and the outer guide vane (404) is a twisted blade. The outer guide vane ring (405) is fixed on the inner wall of the housing (1). The center line of the axial section of the middle guide vane ring (403) has an angle A with the center line of the main shaft (11), where 0° < A ≤ 30°. The inner guide vane (402) is provided with a through hole (406) with an axial projection quadrilateral structure. The connection between the outer guide vane (404) and the middle guide vane ring (403) is provided with an arc-shaped protrusion (407).
2. A small hydroelectric power generation device for pipelines as described in claim 1, characterized in that, The center line of the axial section of the middle ring (403) of the first guide vane (41) is at an angle A1 with the center line of the main shaft (11), the center line of the axial section of the middle ring (403) of the second guide vane (42) is at an angle A2 with the center line of the main shaft (11), the center line of the axial section of the middle ring (403) of the third guide vane (43) is at an angle A3 with the center line of the main shaft (11), and the center line of the axial section of the middle ring (403) of the outlet guide vane (44) is at an angle A4 with the center line of the main shaft (11), wherein A1 > A2 > A3 and A4 > 1.2A3.
3. A small hydroelectric power generation device for pipelines as described in claim 1, characterized in that, A1=25°~30°, A2=18°~23°, A3=8°~12°, A4=10°~16°.
4. A small hydroelectric power generation device for pipelines as described in claim 1, characterized in that, The through hole (406) is located on the side closer to the guide vane middle ring (403).
5. A small hydroelectric power generation device for pipelines as described in claim 1, characterized in that, Quadrilateral structures can be rectangular, rhomboid, or trapezoidal.
6. A small hydroelectric power generation device for pipelines as described in claim 1, characterized in that, The outline of the arcuate protrusion (407) is part of the Archimedean spiral.
7. A small hydroelectric power generation device for pipelines as described in claim 1, characterized in that, The radial length of the outer guide vane (404) is L1, and the radial length of the inner guide vane (402) is L2, with L1:L2 = 1.2 to 2.
5.
8. A small hydroelectric power generation device for pipelines as described in claim 7, characterized in that, The hub (51) protrudes radially from the inner ring (401) of the guide vane, wherein the protruding portion is provided with a through pressure boosting hole (52).
9. A small hydroelectric power generation device for pipelines as described in claim 8, characterized in that, The diameter of the pressure boosting hole (52) is D, where D = (0.1~0.3) L2.
10. A small hydroelectric power generation device for pipelines as described in claim 9, characterized in that, The flow direction of the pressure boosting hole (52) is consistent with the direction of the blade root of the blade (50).
11. A small hydroelectric power generation device for pipelines as described in claim 10, characterized in that, The flow channel profile of the pressure boosting hole (52) is "S" shaped.
12. A small hydroelectric power generation device for pipelines as described in claim 11, characterized in that, The number of pressure-boosting holes (52) is less than the number of blades (50).