Adjustable blade of water turbine, mounting method, runner and application

Abstract

The invention discloses an adjustable blade of a water turbine, a mounting method, a runner and application, and belongs to the technical field of water turbines, the adjustable blade comprises a blade body, a blade adjusting mechanism and a pivot, the blade adjusting mechanism comprises a rotary hydraulic cylinder, a fixed ring plate and a push-pull rod, the fixed ring plate is connected to a rotary shaft of the rotary hydraulic cylinder, and the push-pull rod is connected to the fixed ring plate; one end of the push-pull rod is hinged to the fixed ring plate, the other end of the push-pull rod is hinged to one end of the pivot, and the other end of the pivot is fixedly connected with the blade body. According to different working conditions of the water turbine, the adjustable blades can be adjusted along with rotation of the pivot, the flow characteristics of the blades and a runner channel and the hydraulic performance of the water turbine under the non-optimal working condition are effectively improved, and wide-load operation of the water turbine is easy to achieve.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic turbines, and particularly to an adjustable blade of a hydraulic turbine, an installation method, a runner and an application thereof. Background Art

[0002] With the rapid development of the new energy industry, due to the inflexible characteristics of these new energy powers themselves, the function of conventional hydropower units has gradually changed from simple power generation to providing flexible regulation services such as peak shaving and frequency modulation. This poses higher requirements for the wide-load operation of Francis turbines.

[0003] Currently, Francis turbines have a fixed blade type, and the blades are fixedly connected to the upper crown and the lower ring. The non-adjustability of the Francis turbine blades limits the adjustment of the unit operation range to a certain extent, and it is difficult to achieve the wide-load operation of Francis turbines.

[0004] Chinese patent document with publication number CN117514563A and publication date February 6, 2024 discloses an adjustable blade type hydraulic turbine, which includes a runner chamber. A sealing seat ring is fixedly installed at the top of the runner chamber. A fixing frame is fixedly installed inside the sealing seat ring. At least two support plates are fixedly installed on the outside of the fixing frame. A top plate is fixedly installed at the top of the sealing seat ring. A main shaft is rotatably installed inside the top plate. A first runner body is fixedly installed at the bottom end of the main shaft. At least two blade bodies are fixedly installed on the surface of the first runner body. A second runner body is movably installed at the bottom end of the first runner body. At least two guide vanes are rotatably installed inside the sealing seat ring. A fixing shaft is fixedly installed at the bottom end of each guide vane; Among them, each guide vane is inclinedly installed inside the sealing seat ring, and the spacing between each guide vane is the same. At the same time, blade bodies are also installed on the surface of the second runner body, and the top end of the second runner body fits with the bottom end of the blade body.

[0005] For the adjustable blade type hydraulic turbine disclosed in this patent document, when the water flow rate changes, the rotational speed and kinetic energy utilization rate of the hydraulic turbine are improved, ensuring the stability and flexibility of the power generation efficiency. However, since it cannot effectively improve the flow characteristics of the blade and the runner passage and the hydraulic performance of the hydraulic turbine under non-optimal conditions, it is difficult to achieve the wide-load operation of the hydraulic turbine. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides an adjustable blade of a hydraulic turbine, an installation method, a runner and an application thereof. For different working conditions of the hydraulic turbine, the adjustable blade can rotate and adjust along with the pivot shaft, effectively improving the flow characteristics of the blade and the runner passage and the hydraulic performance of the hydraulic turbine under non-optimal conditions, and it is easy to achieve the wide-load operation of the hydraulic turbine.

[0007] The present invention is realized through the following technical solutions: An adjustable blade for a water turbine, comprising a blade body, a blade adjusting mechanism and a pivot shaft. The blade adjusting mechanism includes a rotary hydraulic cylinder, a fixed ring plate and a push-pull rod. The fixed ring plate is connected to the rotary shaft of the rotary hydraulic cylinder. One end of the push-pull rod is hinged to the fixed ring plate, and the other end of the push-pull rod is hinged to one end of the pivot shaft. The other end of the pivot shaft is fixedly connected to the blade body.

[0008] A runner of a water turbine, comprising a lower ring, adjustable blades, fixed blades and a crown installed on the main shaft of the water turbine. The rotary hydraulic cylinder of the adjustable blade is fixed at the end of the main shaft of the water turbine. The pivot shaft of the adjustable blade is arranged on the crown. The blade body of the adjustable blade is fixedly connected to the pivot shaft. A first gap is provided between one side of the blade body and the inner surface of the crown, and a second gap is provided between the other side of the blade body and the inner surface of the lower ring. One end of the fixed blade is fixedly connected to the crown, and the other end of the fixed blade is fixedly connected to the lower ring.

[0009] The blade body includes an upper spherical surface portion of the blade and a lower spherical surface portion of the blade. The upper spherical surface portion of the blade and the lower spherical surface portion of the blade are concentric spherical surfaces.

[0010] Both the adjustable blades and the fixed blades are multiple, and the number of blade bodies of the adjustable blades is the same as the number of the fixed blades.

[0011] The blade bodies of the adjustable blades are evenly arranged circumferentially along the crown and the lower ring.

[0012] Both the inner surface of the crown and the inner surface of the lower ring are spherical surfaces. The rotation axis of the pivot shaft passes through the center of the sphere of the crown and the center of the sphere of the lower ring. The center of the sphere of the crown and the center of the sphere of the lower ring are the same center of the sphere.

[0013] The rotation axis of the pivot shaft forms an angle of 30 - 60° with the center line of the main shaft of the water turbine.

[0014] The size of the fixed blade is smaller than the size of the blade body of the adjustable blade, and the fixed blade is located in the middle of the axial section of the blade body.

[0015] The fixed blade is located between any two adjacent blade bodies.

[0016] An installation method for an adjustable blade of a water turbine, installing the blade bodies of multiple adjustable blades evenly along the circumference of the crown and the lower ring of the runner of the water turbine, so that the head of the blade body is close to the inlet of the runner of the water turbine, and the tail of the blade body is close to the outlet of the runner of the water turbine.

[0017] An application of an adjustable blade of a water turbine, applicable to the runner of a water turbine.

[0018] An application of a runner of a water turbine, applicable to a Francis turbine.

[0019] The beneficial effects of the present invention are mainly manifested in the following aspects: 1. Compared with the prior art, in the present invention, for different operating conditions of the water turbine, the adjustable blades can rotate and adjust along the pivot axis, effectively improving the flow characteristics of the blades and the runner passage, as well as the hydraulic performance of the water turbine under non-optimal operating conditions, and facilitating the wide-load operation of the water turbine.

[0020] 2. In the present invention, fixed blades are used in combination with specific adjustable blades as the blades of the water turbine runner. The formed water turbine runner, compared with the water turbine runner of the prior art, has adjustable blades that can rotate and adjust, which can improve the hydraulic performance of the water turbine runner under non-optimal operating conditions, thereby realizing the wide-load operation of the water turbine, especially the wide-load operation of the Francis turbine.

[0021] 3. In the present invention, the blade body includes an upper spherical surface portion and a lower spherical surface portion of the blade. The upper spherical surface portion and the lower spherical surface portion of the blade are concentric spherical surfaces, so that a fixed gap is always maintained between the upper spherical surface portion of the blade and the inner surface of the upper crown, and between the lower spherical surface portion of the blade and the inner surface of the lower ring, facilitating the rotation and adjustment of the adjustable blade along the concentric spherical surfaces.

[0022] 4. In the present invention, there are multiple adjustable blades and fixed blades. The number of blade bodies of the adjustable blades is the same as the number of fixed blades, having the characteristics of a rotary power machine such as uniform circumferential flow characteristics and uniform and balanced work.

[0023] 5. In the present invention, the blade bodies of the adjustable blades are circumferentially and uniformly arranged along the upper crown and the lower ring, having the characteristics of good uniformity of fluid flowing through the blades, small turbulence and energy loss; and making the stress distribution of the water turbine runner more uniform and the local stress concentration small.

[0024] 6. In the present invention, the inner surfaces of the upper crown and the lower ring are both spherical surfaces. The rotation axis of the pivot passes through the center of the sphere of the upper crown and the center of the sphere of the lower ring. The center of the sphere of the upper crown and the center of the sphere of the lower ring are the same center of the sphere, enabling the adjustable blade to rotate and adjust flexibly between the upper crown and the lower ring.

[0025] 7. In the present invention, the rotation axis of the pivot forms an angle of 30-60° with the center line of the water turbine main shaft, which can adapt to the runner geometric types of Francis turbines with different water heads, ensuring that the rotation axis of the adjustable blade passes through the middle region of the adjustable blade.

[0026] 8. In the present invention, the size of the fixed blade is smaller than the size of the blade body of the adjustable blade. The fixed blade is located in the middle of the axial section of the blade body. The smaller fixed blade reduces the interference to the main flow, making the fluid flow more smoothly towards the adjustable blade.

[0027] 9. In the present invention, the fixed vanes are located between any two adjacent vane bodies, and in addition, the fixed vanes are located in the middle of the axial section of the vane body. This specific vane arrangement can guide the fluid to flow more uniformly towards the adjustable vanes, reducing turbulence and energy loss; the fixed vanes enhance the overall rigidity of the turbine runner and provide better support for the adjustable vanes, enabling the adjustable vanes to be adjusted more flexibly according to different operating conditions.

[0028] 10. In the present invention, the vane bodies of multiple adjustable vanes are evenly installed along the circumferences of the crown and the lower ring of the turbine runner, with the head of the vane body close to the inlet of the turbine runner and the tail of the vane body close to the outlet of the turbine runner. By adopting this specific installation, the incidence angle of the head of the vane body can be reduced at the inlet of the turbine runner to adapt to the incoming flow, and the axial flow velocity and circumferential flow velocity can be reduced at the outlet of the turbine runner, improving the flow characteristics and hydraulic performance inside the turbine runner under non-optimal operating conditions and achieving wide-load operation of the turbine. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further specifically described below in conjunction with the specification drawings and specific embodiments, where: Figure 1 is a cross-sectional view of the turbine runner of the present invention; Figure 2 is a structural schematic diagram of the turbine runner of the present invention; Figure 3 is a top view of the turbine runner of the present invention; Figure 4 is a partial view of the turbine runner of the present invention; Reference numerals in the drawings: 1, vane body; 2, pivot; 3, rotary hydraulic cylinder; 4, fixed ring plate; 5, push-pull rod; 6, crown; 7, lower ring; 8, fixed vane; 9, turbine main shaft; 10, first gap; 11, second gap; 12, upper spherical surface part of the vane; 13, lower spherical surface part of the vane. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] Embodiment 1 See Figure 1 , an adjustable vane of a turbine, including a vane body 1, a vane adjusting mechanism and a pivot 2. The vane adjusting mechanism includes a rotary hydraulic cylinder 3, a fixed ring plate 4 and a push-pull rod 5. The fixed ring plate 4 is connected to the rotating shaft of the rotary hydraulic cylinder 3. One end of the push-pull rod 5 is hinged to the fixed ring plate 4, and the other end of the push-pull rod 5 is hinged to one end of the pivot 2. The other end of the pivot 2 is fixedly connected to the vane body 1.

[0031] This embodiment is the most basic implementation mode. Compared with the prior art, for different operating conditions of the water turbine, the adjustable blades can rotate and adjust along with the pivot 2, effectively improving the flow characteristics of the blades and the runner passage as well as the hydraulic performance of the water turbine under non-optimal operating conditions, and facilitating the wide-load operation of the water turbine.

[0032] Embodiment 2 See Figures 1 - 4 , a water turbine runner, including a lower ring 7, adjustable blades, fixed blades 8 and a crown 6 mounted on the water turbine main shaft 9. The rotary hydraulic cylinder 3 of the adjustable blades is fixed at the end of the water turbine main shaft 9. The pivot 2 of the adjustable blades is arranged on the crown 6. The blade body 1 of the adjustable blades is fixedly connected with the pivot 2. A first gap 10 is arranged between one side of the blade body 1 and the inner surface of the crown 6, and a second gap 11 is arranged between the other side of the blade body 1 and the inner surface of the lower ring 7. One end of the fixed blade 8 is fixedly connected with the crown 6, and the other end of the fixed blade 8 is fixedly connected with the lower ring 7.

[0033] This embodiment is another preferred implementation mode. By using the fixed blades 8 in combination with specific adjustable blades as the blades of the water turbine runner, the formed water turbine runner, compared with the water turbine runner of the prior art, the adjustable blades can rotate and adjust, which can improve the hydraulic performance of the water turbine runner under non-optimal operating conditions, thereby realizing the wide-load operation of the water turbine, especially the wide-load operation of the Francis turbine.

[0034] Embodiment 3 See Figures 1 - 4 , a water turbine runner, including a lower ring 7, adjustable blades, fixed blades 8 and a crown 6 mounted on the water turbine main shaft 9. The rotary hydraulic cylinder 3 of the adjustable blades is fixed at the end of the water turbine main shaft 9. The pivot 2 of the adjustable blades is arranged on the crown 6. The blade body 1 of the adjustable blades is fixedly connected with the pivot 2. A first gap 10 is arranged between one side of the blade body 1 and the inner surface of the crown 6, and a second gap 11 is arranged between the other side of the blade body 1 and the inner surface of the lower ring 7. One end of the fixed blade 8 is fixedly connected with the crown 6, and the other end of the fixed blade 8 is fixedly connected with the lower ring 7.

[0035] Preferably, the blade body 1 includes an upper spherical surface part 12 and a lower spherical surface part 13 of the blade, and the upper spherical surface part 12 and the lower spherical surface part 13 of the blade are concentric spherical surfaces.

[0036] This embodiment is another preferred implementation mode. The blade body 1 includes an upper spherical surface part 12 and a lower spherical surface part 13 of the blade, and the upper spherical surface part 12 and the lower spherical surface part 13 of the blade are concentric spherical surfaces, so that a fixed gap is always maintained between the upper spherical surface part 12 of the blade and the inner surface of the crown 6 and between the lower spherical surface part 13 of the blade and the inner surface of the lower ring 7, facilitating the rotary adjustment of the adjustable blades along the concentric spherical surfaces.

[0037] Embodiment 4 Refer to Figures 1 - 4 , a water turbine runner, including a lower ring 7, adjustable blades, fixed blades 8 and a crown 6 mounted on the water turbine main shaft 9. The rotary hydraulic cylinder 3 of the adjustable blade is fixed at the end of the water turbine main shaft 9. The pivot shaft 2 of the adjustable blade is arranged on the crown 6. The blade body 1 of the adjustable blade is fixedly connected to the pivot shaft 2. A first gap 10 is provided between one side of the blade body 1 and the inner surface of the crown 6, and a second gap 11 is provided between the other side of the blade body 1 and the inner surface of the lower ring 7. One end of the fixed blade 8 is fixedly connected to the crown 6, and the other end of the fixed blade 8 is fixedly connected to the lower ring 7.

[0038] The blade body 1 includes a blade upper spherical surface portion 12 and a blade lower spherical surface portion 13, and the blade upper spherical surface portion 12 and the blade lower spherical surface portion 13 are concentric spherical surfaces.

[0039] Both the adjustable blades and the fixed blades 8 are multiple, and the number of the blade bodies 1 of the adjustable blades is the same as the number of the fixed blades 8.

[0040] This embodiment is another preferred embodiment. Both the adjustable blades and the fixed blades 8 are multiple, and the number of the blade bodies 1 of the adjustable blades is the same as the number of the fixed blades 8, having the characteristics of a rotary power machine such as uniform circumferential flow characteristics and uniform and balanced work.

[0041] Embodiment 5 Refer to Figures 1 - 4 , a water turbine runner, including a lower ring 7, adjustable blades, fixed blades 8 and a crown 6 mounted on the water turbine main shaft 9. The rotary hydraulic cylinder 3 of the adjustable blade is fixed at the end of the water turbine main shaft 9. The pivot shaft 2 of the adjustable blade is arranged on the crown 6. The blade body 1 of the adjustable blade is fixedly connected to the pivot shaft 2. A first gap 10 is provided between one side of the blade body 1 and the inner surface of the crown 6, and a second gap 11 is provided between the other side of the blade body 1 and the inner surface of the lower ring 7. One end of the fixed blade 8 is fixedly connected to the crown 6, and the other end of the fixed blade 8 is fixedly connected to the lower ring 7.

[0042] The blade body 1 includes a blade upper spherical surface portion 12 and a blade lower spherical surface portion 13, and the blade upper spherical surface portion 12 and the blade lower spherical surface portion 13 are concentric spherical surfaces.

[0043] Further preferably, both the adjustable blades and the fixed blades 8 are multiple, and the number of the blade bodies 1 of the adjustable blades is the same as the number of the fixed blades 8.

[0044] The blade bodies 1 of the adjustable blades are uniformly arranged circumferentially along the crown 6 and the lower ring 7.

[0045] This embodiment is another preferred embodiment. The blade bodies 1 of the adjustable blades are circumferentially and uniformly arranged along the upper crown 6 and the lower ring 7, featuring good uniformity of fluid flow through the blades, small turbulence and energy loss; moreover, it makes the stress distribution of the water turbine runner more uniform with less local stress concentration.

[0046] Embodiment 6 See Figures 1 - 4 , a water turbine runner, comprising a lower ring 7, adjustable blades, fixed blades 8 and an upper crown 6 mounted on the water turbine main shaft 9. The rotary hydraulic cylinders 3 of the adjustable blades are fixed to the end of the water turbine main shaft 9. The pivot shafts 2 of the adjustable blades are arranged on the upper crown 6. The blade bodies 1 of the adjustable blades are fixedly connected to the pivot shafts 2. A first gap 10 is provided between one side of the blade body 1 and the inner surface of the upper crown 6, and a second gap 11 is provided between the other side of the blade body 1 and the inner surface of the lower ring 7. One end of the fixed blade 8 is fixedly connected to the upper crown 6, and the other end of the fixed blade 8 is fixedly connected to the lower ring 7.

[0047] The blade body 1 includes a blade upper spherical surface portion 12 and a blade lower spherical surface portion 13, and the blade upper spherical surface portion 12 and the blade lower spherical surface portion 13 are concentric spherical surfaces.

[0048] Both the adjustable blades and the fixed blades 8 are multiple in number, and the number of the blade bodies 1 of the adjustable blades is the same as the number of the fixed blades 8.

[0049] The blade bodies 1 of the adjustable blades are circumferentially and uniformly arranged along the upper crown 6 and the lower ring 7.

[0050] The inner surfaces of the upper crown 6 and the lower ring 7 are both spherical surfaces. The rotation axis of the pivot shaft 2 passes through the center of the sphere of the upper crown 6 and the center of the sphere of the lower ring 7, and the center of the sphere of the upper crown 6 and the center of the sphere of the lower ring 7 are the same center of the sphere.

[0051] This embodiment is another preferred embodiment. The inner surfaces of the upper crown 6 and the lower ring 7 are both spherical surfaces. The rotation axis of the pivot shaft 2 passes through the center of the sphere of the upper crown 6 and the center of the sphere of the lower ring 7, and the center of the sphere of the upper crown 6 and the center of the sphere of the lower ring 7 are the same center of the sphere, enabling the adjustable blades to rotate and adjust flexibly between the upper crown 6 and the lower ring 7.

[0052] Embodiment 7 See Figures 1 - 4, A water turbine runner, comprising a lower ring 7, adjustable blades, fixed blades 8 and a crown 6 mounted on the water turbine main shaft 9. The rotary hydraulic cylinder 3 of the adjustable blades is fixed to the end of the water turbine main shaft 9. The pivot shaft 2 of the adjustable blades is arranged on the crown 6. The blade body 1 of the adjustable blades is fixedly connected to the pivot shaft 2. A first gap 10 is provided between one side of the blade body 1 and the inner surface of the crown 6, and a second gap 11 is provided between the other side of the blade body 1 and the inner surface of the lower ring 7. One end of the fixed blade 8 is fixedly connected to the crown 6, and the other end of the fixed blade 8 is fixedly connected to the lower ring 7.

[0053] The blade body 1 includes a blade upper spherical surface portion 12 and a blade lower spherical surface portion 13, and the blade upper spherical surface portion 12 and the blade lower spherical surface portion 13 are concentric spherical surfaces.

[0054] Both the adjustable blades and the fixed blades 8 are multiple, and the number of the blade bodies 1 of the adjustable blades is the same as the number of the fixed blades 8.

[0055] The blade bodies 1 of the adjustable blades are circumferentially and uniformly arranged along the crown 6 and the lower ring 7.

[0056] More preferably, the inner surfaces of the crown 6 and the lower ring 7 are both spherical surfaces. The rotation axis of the pivot shaft 2 passes through the centers of the spheres of the crown 6 and the lower ring 7, and the centers of the spheres of the crown 6 and the lower ring 7 are the same center of the sphere.

[0057] The rotation axis of the pivot shaft 2 forms an angle of 30° with the center line of the water turbine main shaft 9.

[0058] The size of the fixed blade 8 is smaller than the size of the blade body 1 of the adjustable blade, and the fixed blade 8 is located in the middle of the axial section of the blade body 1.

[0059] This embodiment is another preferred embodiment. The size of the fixed blade 8 is smaller than the size of the blade body 1 of the adjustable blade, and the fixed blade 8 is located in the middle of the axial section of the blade body 1. The smaller fixed blade 8 reduces the interference with the main flow and makes the fluid flow more smoothly towards the adjustable blades.

[0060] Embodiment 8 See Figures 1 - 4 , A water turbine runner, comprising a lower ring 7, adjustable blades, fixed blades 8 and a crown 6 mounted on the water turbine main shaft 9. The rotary hydraulic cylinder 3 of the adjustable blades is fixed to the end of the water turbine main shaft 9. The pivot shaft 2 of the adjustable blades is arranged on the crown 6. The blade body 1 of the adjustable blades is fixedly connected to the pivot shaft 2. A first gap 10 is provided between one side of the blade body 1 and the inner surface of the crown 6, and a second gap 11 is provided between the other side of the blade body 1 and the inner surface of the lower ring 7. One end of the fixed blade 8 is fixedly connected to the crown 6, and the other end of the fixed blade 8 is fixedly connected to the lower ring 7.

[0061] The blade body 1 includes an upper spherical surface portion 12 and a lower spherical surface portion 13 of the blade, and the upper spherical surface portion 12 and the lower spherical surface portion 13 of the blade are concentric spherical surfaces.

[0062] There are multiple adjustable blades and fixed blades 8, and the number of blade bodies 1 of the adjustable blades is the same as the number of fixed blades 8.

[0063] The blade bodies 1 of the adjustable blades are circumferentially and uniformly arranged along the upper crown 6 and the lower ring 7.

[0064] The inner surfaces of the upper crown 6 and the lower ring 7 are both spherical surfaces. The rotation axis of the pivot 2 passes through the centers of the spheres of the upper crown 6 and the lower ring 7, and the centers of the spheres of the upper crown 6 and the lower ring 7 are the same center of the sphere.

[0065] The rotation axis of the pivot 2 forms an angle of 60° with the center line of the water turbine main shaft 9.

[0066] The size of the fixed blade 8 is smaller than the size of the blade body 1 of the adjustable blade, and the fixed blade 8 is located in the middle of the axial section of the blade body 1.

[0067] The fixed blade 8 is located between any two adjacent blade bodies 1.

[0068] This embodiment is the best implementation mode. The fixed blade 8 is located between any two adjacent blade bodies 1, and in addition, the fixed blade 8 is located in the middle of the axial section of the blade body 1. This specific blade arrangement can guide the fluid to flow more uniformly to the adjustable blades, reducing turbulence and energy loss; the fixed blade 8 enhances the overall rigidity of the water turbine runner, provides better support for the adjustable blades, and enables the adjustable blades to be adjusted more flexibly according to different operating conditions.

[0069] Embodiment 9 See Figures 1 - 3 , a method for installing adjustable blades of a water turbine, in which the blade bodies 1 of multiple adjustable blades are circumferentially and uniformly installed along the upper crown 6 and the lower ring 7 of the water turbine runner, so that the head of the blade body 1 is close to the inlet of the water turbine runner and the tail of the blade body 1 is close to the outlet of the water turbine runner.

[0070] Adopting this specific installation can reduce the head attack angle of the blade body 1 at the inlet of the water turbine runner to adapt to the incoming flow, reduce the axial flow velocity and circumferential flow velocity at the outlet of the water turbine runner, improve the flow characteristics and hydraulic performance inside the water turbine runner under non-optimal conditions, and achieve the wide-load operation of the water turbine.

[0071] The working principle of the blade adjusting mechanism of the present invention is as follows: When the adjustable blade needs to be rotationally adjusted, by increasing or decreasing the oil pressure in the rotary hydraulic cylinder 3 of the blade adjusting mechanism, a thrust or a pulling force is generated on the push-pull rod 5, and the adjustable blade is pushed or pulled to rotate around the pivot 2 in the positive rotation angle or negative rotation angle direction.

[0072] The working principle of the water turbine runner of the present invention is as follows: When the water turbine runner is working, after the water flow enters through the inlet of the water turbine runner, the water flow acts on the adjustable blade and the fixed blade 8, and the water turbine runner is pushed to rotate and do work through the pressure difference between the front and back surfaces of the blade. When the output of the water turbine changes, that is, during the operating condition adjustment, the water flow rate entering the water turbine runner increases, that is, the output increases, or the water flow rate entering the water turbine runner decreases, that is, the output decreases, and the corresponding inflow angle increases or decreases; at this time, the adjustable blade can be adjusted through the blade adjusting mechanism. The positive rotation angle position of the adjustable blade corresponds to the large flow rate condition, and the negative rotation angle position of the adjustable blade corresponds to the small flow rate condition. By adjusting the adjustable blade to adapt to the incoming flow rate and the incoming flow angle, the pressure distribution on the front and back surfaces of the adjustable blade is improved, and the head attack angle of the adjustable blade and the axial flow velocity and circumferential flow velocity at the outlet of the water turbine runner are reduced; the upper crown 6 and the lower ring 7 of the water turbine runner are connected through the fixed blade 8 to ensure the mechanical strength of the water turbine runner, and at the same time play a role in guiding the flow and forming a pressure difference to push the water turbine runner to do work.

Claims

1. A water turbine adjustable blade, comprising a blade body (1), characterized in that: It also includes a blade adjustment mechanism and a pivot (2), wherein the blade adjustment mechanism includes a rotating hydraulic cylinder (3), a fixed ring plate (4) and a push-pull rod (5), wherein the fixed ring plate (4) is connected to the rotating shaft of the rotating hydraulic cylinder (3), one end of the push-pull rod (5) is hinged to the fixed ring plate (4), the other end of the push-pull rod (5) is hinged to one end of the pivot (2), and the other end of the pivot (2) is fixedly connected to the blade body (1).

2. A turbine runner, comprising a lower ring (7) and an upper crown (6) mounted on a main shaft (9) of the turbine, characterized in that: It also includes an adjustable blade and a fixed blade (8), wherein a rotating hydraulic cylinder (3) of the adjustable blade is fixed to the end of a main shaft (9) of the turbine, a pivot shaft (2) of the adjustable blade is arranged on an upper crown (6), a blade body (1) of the adjustable blade is fixedly connected to the pivot shaft (2), a first gap (10) is arranged between one side of the blade body (1) and the inner surface of the upper crown (6), a second gap (11) is arranged between the other side of the blade body (1) and the inner surface of the lower ring (7), one end of the fixed blade (8) is fixedly connected to the upper crown (6), and the other end of the fixed blade (8) is fixedly connected to the lower ring (7).

3. A water turbine runner according to claim 2, characterized in that: The blade body (1) comprises an upper blade spherical portion (12) and a lower blade spherical portion (13), and the upper blade spherical portion (12) and the lower blade spherical portion (13) are concentric spherical surfaces.

4. A water turbine runner according to claim 2, characterized in that: The adjustable blades and the fixed blades (8) are both multiple, and the number of the blade bodies (1) of the adjustable blades is the same as the number of the fixed blades (8).

5. A water turbine runner according to claim 2, characterized in that: The blade bodies (1) of the adjustable blades are evenly arranged along the circumference of the upper crown (6) and the lower ring (7).

6. A water turbine runner according to claim 2, characterized in that: The inner surface of the upper crown (6) and the inner surface of the lower ring (7) are both spherical surfaces, the rotation axis of the pivot (2) passes through the center of the upper crown (6) and the center of the lower ring (7), and the center of the upper crown (6) and the center of the lower ring (7) are the same center.

7. A water turbine runner according to claim 2, characterized in that: The rotation axis of the pivot (2) forms an angle of 30-60° with the center line of the turbine main shaft (9).

8. A water turbine runner according to claim 2, characterized in that: The size of the fixed blade (8) is smaller than the blade body (1) of the adjustable blade, and the fixed blade (8) is located in the middle of the axial cross section of the blade body (1).

9. A water turbine runner according to claim 2, characterized in that: The fixed blade (8) is located between any two adjacent blade bodies (1).

10. A method for installing adjustable blades of a water turbine, characterized in that: The adjustable turbine blades as claimed in claim 1 are used to evenly install blade bodies (1) of a plurality of adjustable blades along the circumference of an upper crown (6) and a lower ring (7) of a turbine runner, so that the head of the blade body (1) is close to the turbine runner inlet and the tail of the blade body (1) is close to the turbine runner outlet.

11. An application of adjustable blades for a water turbine, characterized in that: The adjustable water turbine blade as claimed in claim 1 is suitable for a water turbine runner.

12. An application of a water turbine runner, characterized in that: The water turbine runner as claimed in claim 2 is suitable for a Francis turbine.

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