A hydraulic turbine with small flow and high head

Abstract

The present invention discloses a small-flow and high-lift hydraulic turbine, in which water at a water inlet interface is sprayed out from a nozzle through a nozzle pipe, and the sprayed water impacts on the airfoil blades to drive the impeller to rotate, thereby driving a rotor connected to the impeller to rotate, thereby driving a power output shaft to rotate to output power, and water in the rotor cavity is discharged through a drainage channel via a water outlet interface. In this embodiment, by distributing a sufficient number of airfoil blades that meet dynamic characteristics on the impeller, the liquid energy recovery efficiency can be greatly improved. At the same time, along the radial direction of the rotor cavity, the inner diameter of the nozzle gradually decreases. By adopting a streamlined compression design, it brings a qualitative leap compared to the traditional multi-stage pump-type hydraulic turbine nozzle-free tube design, so that the liquid energy of small flow and high pressure can be recovered. In addition, by arranging the nozzle to be located in the rotor cavity and close to the airfoil blade, the flow loss can be greatly reduced and the efficiency can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic turbines, in particular to a hydraulic turbine with small flow and high lift. Background Art

[0002] A hydraulic turbine is an energy recovery device, a machine that converts the energy contained in a fluid working medium into mechanical energy. The most important component of a turbine is a rotating element, namely a rotor, or impeller, which is installed on the turbine shaft and has blades evenly arranged along the circumference. The energy of the fluid is converted into kinetic energy when it flows through the impeller. When the fluid flows through the impeller, it impacts the blades, pushing the impeller to rotate, thereby driving the turbine shaft to rotate. The turbine shaft drives other machinery directly or through a transmission mechanism to output mechanical work.

[0003] Existing hydraulic turbines usually adopt a multi-stage pump reverse structure, and the hydraulic turbine inlet is a large flange structure, the number of impeller blades is small, the impeller inlet is large, and the rotor weight is large. Hydraulic turbines with this structure are only suitable for large flow conditions. At the same time, the axial component force generated when the liquid flows through the blades is large, and an axial force balancing device needs to be configured. When a turbine with this structure is used in a working condition where the liquid medium that needs to recover energy has a small flow rate, even the high pressure of the liquid will still cause the turbine unit to have difficulty in starting the hydraulic turbine, resulting in the inability to recover the liquid medium energy. Summary of the invention

[0004] The purpose of the present invention is to provide a small flow rate and high lift hydraulic turbine, which solves the problem of high pressure and small flow rate liquid energy recovery in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A small flow rate and high lift hydraulic turbine, comprising a power output shaft and an inlet and outlet water section, a rotating section and an output section connected in sequence along the axial direction of the power output shaft, wherein the inlet and outlet water section is provided with an accommodating cavity, and the inlet and outlet water sections are respectively provided with an inlet interface and a water outlet interface communicating with the accommodating cavity;

[0007] The rotating section includes a shell, a rotor, an impeller and a nozzle. The shell has an installation cavity, and the rotor is arranged in the installation cavity. One side of the rotor is connected to one end of the power output shaft, and the other side of the rotor is connected to the impeller, and a rotor cavity is formed between the rotor and the impeller. A plurality of airfoil blades are arranged on one side of the impeller located in the rotor cavity. A drainage channel connecting the impeller and the water outlet interface is arranged in the rotor cavity. One end of the nozzle is connected to the water inlet interface, and the other end of the nozzle extends into the rotor cavity. A nozzle is arranged at the end of the nozzle. The nozzle is located in the rotor cavity and is arranged close to the airfoil blade. The inner diameter of the nozzle gradually decreases along the flow direction of the liquid in the nozzle.

[0008] Furthermore, the impeller is provided with a step, the step is arranged close to the outer peripheral wall of the impeller and facing the airfoil blade, and the step is communicated with the drainage channel;

[0009] And / or the end surface of the impeller facing the airfoil blade gradually becomes thinner from the center to the outer edge in the radial direction, and the drainage channel is connected to the outer edge of the impeller.

[0010] Furthermore, the shell includes a cover plate, the cover plate is connected to the water inlet and outlet sections, and a first sealing structure is provided between the cover plate and the water inlet and outlet sections.

[0011] Furthermore, the first sealing structure includes a sealing dynamic ring and a sealing static ring that cooperate with each other, the sealing dynamic ring is connected to the outer end of the impeller facing the water inlet and outlet sections, and the sealing static ring is connected between the cover plate and the water inlet and outlet sections.

[0012] Furthermore, the nozzle includes a connecting end, a thin shaft section, a supporting neck section, a radial bending section, an axial bending section, and a circumferential bending section which are connected in sequence as one. The connecting end section is fixedly connected to the accommodating cavity and the inlet of the inner diameter of the nozzle is communicated with the water inlet interface. An impeller mouth ring is provided between the impeller and the supporting neck section. The radial bending section, the axial bending section, and the circumferential bending section are located in the rotor cavity and the radial direction of the radial bending section is consistent with that of the rotor. The axial bending section faces the airfoil blade so that the circumferential bending section is close to the airfoil blade. The circumferential bending section is consistent with the rotation direction of the rotor. The nozzle opens at the end of the circumferential bending section. The liquid sprayed from the nozzle is aligned with the concave liquid receiving surface of the airfoil blade. There is a spacing between the radial bending section and the airfoil blade.

[0013] Furthermore, the output section comprises a bearing box, in which a first bearing and a second bearing are arranged, and the power output shaft is slewingly supported by the first bearing and the second bearing respectively.

[0014] Furthermore, an oil cavity is provided in the bearing box, and an oil throwing mechanism is provided on the power output shaft near the first bearing and the second bearing, and the oil throwing mechanism transports the lubricating oil in the oil cavity to the corresponding first bearing and the second bearing.

[0015] Furthermore, the oil-flinging mechanism includes an oil-flinging ring and a retaining sleeve, the oil-flinging ring extends into the oil chamber, the retaining sleeve is connected to the oil-flinging ring and the corresponding first bearing and the second bearing, and the outer diameter of the retaining sleeve gradually increases from the position of the oil-flinging ring to the corresponding first bearing or second bearing end.

[0016] Furthermore, the second bearing is provided with a bearing cover which is connected and fastened to the bearing box.

[0017] The present invention provides a small-flow and high-lift hydraulic turbine, water from the water inlet interface is sprayed from the nozzle through the nozzle pipe, the sprayed water impacts the airfoil blades to drive the impeller to rotate, and then drives the rotor connected to the impeller to rotate, thereby driving the power output shaft to rotate to output power, and the water in the rotor cavity is discharged through the drainage channel through the water outlet interface. In this embodiment, by distributing a sufficient number of airfoil blades that meet the dynamic characteristics on the impeller, the liquid energy recovery efficiency can be greatly improved. At the same time, along the radial direction of the rotor cavity, the inner diameter of the nozzle gradually decreases. By adopting a streamlined compression design, it brings a qualitative leap compared with the traditional multi-stage pump type hydraulic turbine nozzleless tube design, so that small-flow and high-pressure liquid energy can be recovered. The higher the pressure, the higher the number of recovered revolutions, and the more energy is recovered. The entire rotating component has very few parts, small mechanical loss, convenient manufacturing and maintenance, high efficiency, and high cost performance. In addition, by arranging the nozzle in the rotor cavity and close to the airfoil blades, flow losses can be greatly reduced and efficiency can be improved. In this way, almost no axial force component is generated, and the axial force balancing mechanism of the traditional hydraulic turbine can be simplified or even eliminated, thereby greatly improving the turbine efficiency while reducing costs and the difficulty of manufacturing and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the axial cross-section structure of a small flow rate and high lift hydraulic turbine in an embodiment of the present invention;

[0019] Figure 2 1 is a schematic diagram of the radial cross-sectional structure of an impeller of a small flow rate and high lift hydraulic turbine in an embodiment of the present invention;

[0020] Figure 3 is a structural side view of a nozzle in an embodiment of the present invention;

[0021] Figure 4 is a structural front view of a nozzle in an embodiment of the present invention;

[0022] Figure 5 for Figure 1A partial enlarged view of point A in the middle.

[0023] In the figure: 1, power output shaft; 2, water inlet and outlet section; 3, rotating section; 4, output section; 5, first sealing structure; 201, accommodating chamber; 202, water inlet interface; 203, water outlet interface; 301, housing; 302, rotor; 303, impeller; 304, nozzle; 3041, connecting end; 3042, supporting neck; 3043, radial bending section; 3044, axial bending section; 3045, circumferential bending section; 3046, thin shaft section; 30 5. Installation cavity; 306. Rotor cavity; 307. Airfoil blade; 3071. Concave liquid receiving surface; 308. Drainage channel; 309. Nozzle; 310. Step; 311. Cover plate; 312. Impeller mouth ring; 401. Bearing box; 402. First bearing; 403. Second bearing; 404. Oil cavity; 405. Oil throwing ring; 406. Stop sleeve; 407. Bearing cover; 408. Oil return channel; 501. Sealing dynamic ring; 502. Sealing static ring. Implementation

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See also Figures 1 to 5The embodiment of the present invention provides a small flow and high lift hydraulic turbine, comprising a power output shaft 1 and an inlet and outlet water section 2, a rotating section 3 and an output section 4 connected in sequence along the axial direction of the power output shaft 1, wherein the inlet and outlet water section 2 is provided with an accommodating chamber 201, and the inlet and outlet water section 2 is respectively provided with an inlet interface 202 and an outlet interface 203 communicating with the accommodating chamber 201; the rotating section 3 comprises a shell 301, a rotor 302, an impeller 303 and a nozzle 304, wherein the shell 301 is provided with an installation chamber 305, and the rotor 302 is arranged in the installation chamber 305, one side of the rotor 302 is connected to one end of the power output shaft 1, and the other side of the rotor 302 is connected to the impeller 303, and a rotor chamber 306 is formed between the rotor 302 and the impeller 303, and a plurality of airfoil blades 307 are provided on one side of the impeller 303 located in the rotor chamber 306, so that the weight of the impeller 303 is very light, the weight of the rotor 302 is reduced, and it is beneficial to improve the turbine starting performance and the recovery efficiency. The rotor cavity 306 is provided with a drainage channel 308 connecting the impeller 303 and the water outlet interface 203. One end of the nozzle 304 is connected to the water inlet interface 202. The other end of the nozzle 304 extends into the rotor cavity 306. The end of the nozzle 304 is provided with a nozzle 309. The nozzle 309 is located in the rotor cavity 306 and is arranged close to the airfoil blade 307. Along the flow direction of the liquid in the nozzle 304, the inner diameter of the nozzle 304 gradually decreases. Figure 1 As shown, the nozzle 304 has a connecting end 3041 , which is communicated with the water inlet interface 202 , and the connecting end 3041 is located in the accommodating cavity 201 and fixedly connected.

[0026] Specifically, the water or liquid working medium of the water inlet interface 202 is ejected from the nozzle 309 through the nozzle 304, and the ejected water impacts the airfoil blades 307 to drive the impeller 303 to rotate, thereby driving the rotor 302 connected to the impeller 303 to rotate, thereby driving the power output shaft 1 to rotate to output power, and the water in the rotor cavity 306 is discharged through the water outlet interface 203 through the drainage channel 308. In this embodiment, by distributing enough airfoil blades 307 that meet the dynamic characteristics on the impeller 303, the liquid energy recovery efficiency can be greatly improved. rate, and at the same time, along the flow direction of the liquid in the nozzle 304, the inner diameter of the nozzle 304 gradually decreases, so that the liquid medium with a small flow rate can also be ejected at a high pressure to maintain the driving force on the blades. By adopting a streamlined compression design, it brings a qualitative leap compared to the traditional multi-stage pump type hydraulic turbine nozzleless design, so that the energy of the liquid with a small flow rate and high pressure can be recovered. The higher the pressure, the higher the number of revolutions of the impeller during recovery, and the more energy is recovered. The entire rotating component has very few parts, small mechanical losses, convenient manufacturing and maintenance, high efficiency, and high cost performance. In addition, by arranging the nozzle 309 in the rotor cavity 306 and close to the airfoil blade 307, the flow loss can be greatly reduced and the efficiency can be improved.

[0027] The impeller 303 in this embodiment is provided with a step 310, which is close to the outer peripheral wall of the impeller 303 and facing the airfoil blade 307. The step 310 is connected to the drainage channel 308. By providing the step 310, the space between the airfoil blade 307 and the impeller 303 is increased, so that water can flow out of the drainage channel 308 through the step 310. Furthermore, in another embodiment of the present invention, the end surface of the impeller 303 facing the airfoil blade 307 is gradually thinned from the center to the outer edge along the radial direction, and the drainage channel 308 is connected to the outer edge of the impeller 303. In this way, along the radial direction of the impeller 303, the space between the impeller 303 and the airfoil blade 307 is gradually increased, which can further facilitate the outflow of water from the drainage channel 308. That is, when water flows into the nozzle 304, its flow channel changes from large to small to increase the water pressure of the water to facilitate the rotation of the impeller 303, and the flow channel changes from small to large when the water is discharged to reduce the water pressure of the water to facilitate the discharge of the water.

[0028] Furthermore, the shell 301 includes a cover plate 311, which is connected to the water inlet and outlet section 2. A first sealing structure 5 is provided between the cover plate 311 and the water inlet and outlet section 2. The first sealing structure 5 is provided to ensure the smoothness of the rotation of the impeller 303, and at the same time, to prevent water from entering the internal structure of the installation cavity 305 when the impeller 303 rotates, thereby increasing the rotational resistance of the impeller 303 and the rotor 302 to ensure the turbine recovery efficiency. Preferably, the first sealing structure 5 includes a sealing dynamic ring 501 and a sealing static ring 502 that cooperate with each other. The sealing dynamic ring 501 is connected to the outer end of the impeller 303 facing the water inlet and outlet section 2, and the sealing static ring 502 is connected between the cover plate 311 and the water inlet and outlet section 2 to ensure the rotational seal between the installation cavity 305 and the water outlet interface 203 when the impeller 303 rotates.

[0029] In this embodiment, the nozzle 304 includes a connecting end 3041, a thin shaft section 3046, a supporting neck 3042, a radial bending section 3043, an axial bending section 3044, and a circumferential bending section 3045, which are connected in sequence. The connecting end 3041 is fixedly connected to the accommodating cavity 201, and the inlet of the inner diameter of the nozzle 304 is connected to the water inlet interface 202. An impeller ring 312 is provided between the impeller 303 and the supporting neck 3042 to ensure that the nozzle 304 is not affected by the rotation of the impeller 303. The radial bending section 3044, the axial bending section 3044, and the circumferential bending section 3045 are located in the rotor cavity 306, and the radial bending section 3043 is consistent with the radial direction of the rotor 302. The axial bending section 3044 faces the airfoil blade 307 so that the circumferential bending section 3045 is close to the airfoil blade 307. The circumferential bending section 3045 faces the same direction as the rotation direction of the rotor 302. The nozzle 309 opens at the end of the circumferential bending section 3045. The liquid works on the concave receiving liquid surface 3071 of the airfoil blade 307 to push the airfoil blade 307 to drive the impeller 303 to rotate, so that almost no axial force component is generated, and thus the axial force balance mechanism of the traditional hydraulic turbine can be reduced or even eliminated, and the turbine efficiency is greatly improved under the premise of reducing the cost and difficulty of manufacturing and maintenance. There is a spacing between the radial bending section 3043 and the airfoil blade 307. Here, the significance of setting the spacing between the radial bending section 3043 and the airfoil blade 307 is to make the radial bending section 3043 away from the airfoil blade 307 to reduce the resistance of the liquid between the radial bending section 3043 and the airfoil blade 307 when the impeller 303 rotates, which is beneficial to improving the turbine efficiency; the significance of setting the thin shaft section 3046 is that a flow channel is formed between the thin shaft section 3046 and the inner wall of the sealing dynamic ring 501 to smoothly connect the drainage channel 308 and the water outlet interface 203, so that the liquid that has recovered the energy can flow out smoothly, reduce the flow resistance, and further improve the turbine efficiency.

[0030] Furthermore, the output section 4 includes a bearing box 401, in which a first bearing 402 and a second bearing 403 are arranged, and the power output shaft 1 is slewably supported by the first bearing 402 and the second bearing 403, respectively. The first bearing 402 and the second bearing 403 are arranged to ensure smooth rotation of the power output shaft 1 and extend the service life of the power output shaft 1. In order to further improve the smoothness of the rotation of the power output shaft 1, an oil chamber 404 is arranged in the bearing box 401, and an oil throwing mechanism is arranged near the first bearing 402 and the second bearing 403 on the power output shaft 1, and the oil throwing mechanism transports the lubricating oil in the oil chamber 404 to the corresponding first bearing 402 and the second bearing 403 to lubricate the first bearing 402 and the second bearing 403. Specifically, the oil throwing mechanism includes an oil throwing ring 405 and a stopper sleeve 406. The oil throwing ring 405 extends into the oil chamber 404. The stopper sleeve 406 is connected to the oil throwing ring 405 and the corresponding first bearing 402 and the second bearing 403. The outer diameter of the stopper sleeve 406 gradually increases from the position of the oil throwing ring 405 to the corresponding first bearing 402 or second bearing 403. The oil throwing ring 405 rotates with the power output shaft 1 to bring the lubricating oil in the oil chamber 404 to penetrate the stopper sleeve 406. Since the outer diameter of the stopper sleeve 406 gradually increases from one end of the oil throwing ring 405 to the other end, under the action of centrifugal force, the lubricating oil gradually penetrates into the first bearing 402 and the second bearing 403 along the stopper sleeve 406 to achieve lubrication of the bearings. Further, an oil return channel 408 is also provided on the bearing box 401, and the oil return channel 408 connects the first bearing 402 and the oil chamber 404.

[0031] In this embodiment, a bearing pressure cover 407 which is connected and fastened to the bearing box 401 is provided at the second bearing 403 , and the bearing pressure cover 407 is used to ensure that the second bearing 403 is stably installed.

[0032] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0033] In the description of the present invention, it is necessary to understand that the terms "up", "down", "left", "right", "top", "bottom", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0034] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A small flow and high head hydraulic turbine, Features: It comprises a power output shaft and a water inlet and outlet section, a rotating section and an output section which are sequentially connected along the axial direction of the power output shaft, wherein a receiving cavity is arranged in the water inlet and outlet section, and a water inlet interface and a water outlet interface which are communicated with the receiving cavity are respectively arranged on the water inlet and outlet section; The rotating section comprises a shell, a rotor, an impeller and a nozzle, wherein the shell has an installation cavity, the rotor is arranged in the installation cavity, one side of the rotor is connected to one end of the power output shaft, the other side of the rotor is connected to the impeller, and a rotor cavity is formed between the rotor and the impeller, a plurality of airfoil blades are arranged on one side of the impeller located in the rotor cavity, a drainage channel connecting the impeller and the water outlet interface is arranged in the rotor cavity, one end of the nozzle is connected to the water inlet interface, the other end of the nozzle extends into the rotor cavity, a nozzle is arranged at the end of the nozzle, the nozzle is arranged in the rotor cavity close to and toward the airfoil blade, and the inner diameter of the nozzle gradually decreases along the flow direction of the liquid in the nozzle; The impeller is provided with a step, the step is close to the outer peripheral wall of the impeller and faces the airfoil blade, and the step is communicated with the drainage channel; and / or the end surface of the impeller facing the airfoil blade gradually becomes thinner from the center to the outer edge in the radial direction, and the drainage channel is connected to the outer edge of the impeller; The nozzle includes a connecting end, a thin shaft section, a supporting neck section, a radial bending section, an axial bending section, and a circumferential bending section which are connected in sequence as an integral whole. The connecting end section is fixedly connected to the accommodating cavity and the inlet of the inner diameter of the nozzle is communicated with the water inlet interface. An impeller mouth ring is provided between the impeller and the supporting neck section. The radial bending section, the axial bending section, and the circumferential bending section are located in the rotor cavity and the radial direction of the radial bending section is consistent with that of the rotor. The axial bending section faces the airfoil blade so that the circumferential bending section is close to the airfoil blade. The circumferential bending section is consistent with the rotation direction of the rotor. The nozzle opens at the end of the circumferential bending section. The liquid sprayed from the nozzle is aligned with the concave liquid receiving surface of the airfoil blade. There is a spacing between the radial bending section and the airfoil blade.

2. The low flow and high lift hydraulic turbine according to claim 1, Features: The shell includes a cover plate, the cover plate is connected to the water inlet and outlet sections, and a first sealing structure is provided between the cover plate and the water inlet and outlet sections.

3. The low flow and high lift hydraulic turbine according to claim 2, Features: The first sealing structure comprises a sealing dynamic ring and a sealing static ring which cooperate with each other. The sealing dynamic ring is connected to the outer end of the impeller facing the water inlet and outlet sections, and the sealing static ring is connected between the cover plate and the water inlet and outlet sections.

4. The low flow and high lift hydraulic turbine according to any one of claims 1 to 3, Features: The output section comprises a bearing box, in which a first bearing and a second bearing are arranged, and the power output shaft is slewingly supported by the first bearing and the second bearing respectively.

5. The low flow and high lift hydraulic turbine according to claim 4, Features: An oil cavity is provided in the bearing box, and an oil throwing mechanism is provided on the power output shaft near the first bearing and the second bearing. The oil throwing mechanism transports the lubricating oil in the oil cavity to the corresponding first bearing and the second bearing.

6. The low flow and high lift hydraulic turbine according to claim 5, Features: The oil-flinging mechanism includes an oil-flinging ring and a retaining sleeve. The oil-flinging ring extends into the oil chamber. The retaining sleeve is connected to the oil-flinging ring and the corresponding first bearing and the second bearing. The outer diameter of the retaining sleeve gradually increases from the position of the oil-flinging ring to the corresponding first bearing or second bearing end.

7. The low flow and high lift hydraulic turbine according to claim 6, Features: The second bearing is provided with a bearing pressure cover which is connected and fastened to the bearing box.

Images