An axial flow turbine and a power generation system having the same

Abstract

The utility model relates to a waste heat power generation technical field, especially a kind of axial flow turbine and the power generation system with it. Axial flow turbine includes: casing, rotor assembly and two stators. Fluid passage is formed in casing;Casing includes first casing section, second casing section and third casing section sequentially arranged along its axial direction;Two ends of second casing section are respectively with first casing section, third casing section can be dismantled connection;Rotor assembly is located in casing;Rotor assembly includes first rotating shaft and rotor;Two stators are arranged at the axial direction of rotor two ends, and each stator includes second sleeve and the multiple second blades on the inner circumferential surface of second sleeve;First casing section is set on the outer circumferential of one second sleeve, and third casing section is set on the outer circumferential of another second sleeve. The axial flow turbine of the utility model is convenient to install, disassemble and maintain.

Description

Technical Field

[0001] This utility model relates to the field of waste heat power generation technology, and in particular to an axial flow turbine and a power generation system having the same. Background Technology

[0002] As the global energy structure accelerates its transition towards green and low-carbon development, geothermal energy, as a stable, reliable, and highly efficient renewable energy source, is transitioning from regional demonstration applications to large-scale development and utilization, becoming an important component in building a new energy system. Currently, for medium- and low-temperature geothermal resources, the Organic Rankine Cycle (ORC) power generation technology is typically used for thermal energy conversion. This technology converts thermal energy into electrical energy through the circulation of a low-boiling-point organic working fluid.

[0003] However, the radial or screw expanders commonly used in current ORC power generation systems suffer from significant problems in on-site assembly efficiency, with a single disassembly, assembly, and commissioning process taking more than two days. This not only substantially increases project construction and operation and maintenance costs but also leads to severe power generation losses during downtime due to malfunctions, becoming a technical bottleneck restricting the large-scale development of medium- and low-temperature geothermal power generation. Utility Model Content

[0004] In view of the above problems, this utility model is proposed to provide an axial flow turbine and a power generation system having the same, which overcomes or at least partially solves the above problems. The axial flow turbine is easy to install, disassemble and maintain, thereby significantly improving the efficiency of on-site installation, disassembly and maintenance of the overall ORC power generation system.

[0005] Specifically, this utility model provides an axial flow turbine, comprising:

[0006] A housing having a fluid channel formed within it; the housing includes a first housing segment, a second housing segment, and a third housing segment arranged sequentially along its axial direction; both ends of the second housing segment are detachably connected to the first housing segment and the third housing segment, respectively.

[0007] A rotor assembly is located within the housing; the rotor assembly includes a first rotating shaft and a rotor; the rotor includes a first sleeve and a plurality of first blades disposed on the outer circumferential surface of the first sleeve; the first sleeve is sleeved on the first rotating shaft;

[0008] Two stators are disposed at both ends of the rotor along its axial direction. Each stator includes a second sleeve and a plurality of second blades disposed on the inner circumferential surface of the second sleeve. A first housing segment is sleeved on the outer circumference of one of the second sleeves, and a third housing segment is sleeved on the outer circumference of the other second sleeve.

[0009] Optionally, a first outward flange is provided at one end of the first housing segment near the second housing segment;

[0010] One end of the second housing segment is provided with a second outward flange, and the other end is provided with a third outward flange;

[0011] The third housing segment is provided with a fourth outward flange at one end near the second housing segment;

[0012] The first outward flange and the second outward flange abut against each other and are connected by screws;

[0013] The fourth outer flange abuts against the third outer flange and is connected by screws.

[0014] Optionally, a sealing element is provided between the first outer flange and the second outer flange, and between the fourth outer flange and the third outer flange.

[0015] Optionally, the connection between the first housing segment and the second housing segment is located at the midpoint of the axial direction of the second sleeve;

[0016] The connection between the third housing segment and the second housing segment is located at the midpoint of the axial direction of another second sleeve.

[0017] Optionally, both the first blade and the second blade have a wear-resistant layer on their surfaces;

[0018] The wear-resistant layer is made of one of the following materials: tungsten carbide, titanium nitride, ceramic matrix composite material, and diamond.

[0019] Optionally, the first blade is a first airfoil blade; the second blade is a second airfoil blade.

[0020] Optionally, the first sleeve is assembled from multiple first sleeve segments along the circumferential direction; each first sleeve segment has the first blade disposed on its outer circumferential surface; and / or

[0021] The second sleeve is composed of multiple second sleeve segments spliced ​​together circumferentially; each second sleeve segment has a second blade on its inner circumferential surface.

[0022] Optionally, each of the two ends of the first sleeve component is provided with a groove. After multiple first sleeve components are spliced ​​together, the multiple grooves together form an annular groove at both ends of the first sleeve.

[0023] The first rotating shaft includes two stepped shaft segments arranged opposite each other; each stepped shaft includes a large diameter segment and a small diameter segment, and a stepped surface is formed between the large diameter segment and the small diameter segment, and an annular protrusion is provided on the stepped surface; the two stepped shaft segments are configured such that the two small diameter segments are inserted into the first sleeve from both ends, so that each annular protrusion is inserted into the corresponding annular groove, and each stepped surface abuts against the corresponding end face of the first sleeve.

[0024] Optionally, each of the second sleeve parts has a plug-in portion at one end of its circumference and a plug-in groove at the other end;

[0025] The insertion part of the second sleeve component is inserted into the insertion slot of the adjacent second sleeve component.

[0026] On the other hand, this utility model also provides a power generation system, including:

[0027] Axial flow turbine as described in any of the above;

[0028] A centrifugal compressor having a second rotating shaft; the first rotating shaft is drivingly connected to the second rotating shaft, or the first rotating shaft and the second rotating shaft are coaxially integrally formed.

[0029] In this utility model's power generation system and axial-flow turbine, the axial-flow turbine replaces the existing radial-flow or screw expanders. By employing a three-section detachable housing design, the core components of the axial-flow turbine are modularized, facilitating assembly, disassembly, and maintenance. When maintenance or replacement of the rotor or stator is required, the second housing section can be separated from the first and third housing sections respectively, thus separating the stator and rotor and enabling easy repair. This significantly reduces the traditional 2-3 day disassembly and maintenance time to within one hour, effectively solving the industry pain point of lengthy turbine assembly and maintenance in existing technologies, and significantly improving the operation and maintenance efficiency, availability, and economy of the ORC power generation system.

[0030] Furthermore, by setting the rotor and stator as separate structures, the rotor and / or rotor modularization is achieved, reducing the manufacturing difficulty and cost of the rotor and / or stator.

[0031] The above and other objects, advantages and features of this utility model will become more apparent to those skilled in the art from the following detailed description of specific embodiments of this utility model in conjunction with the accompanying drawings. Attached Figure Description

[0032] The following sections will describe some specific embodiments of the present invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or components. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0033] Figure 1 This is a schematic structural diagram of an axial flow turbine according to an embodiment of the present invention;

[0034] Figure 2 This is a schematic partial structural diagram of an axial flow turbine according to an embodiment of the present invention (the casing is omitted);

[0035] Figure 3 This is a schematic partial structural diagram of an axial flow turbine according to an embodiment of the present invention (the second housing section is omitted);

[0036] Figure 4 This is a schematic structural diagram of the rotor in an axial-flow turbine according to an embodiment of the present invention;

[0037] Figure 5 This is a schematic partial structural diagram of the rotor in an axial-flow turbine according to an embodiment of the present invention;

[0038] Figure 6 This is a schematic structural diagram of the rotor body and the first shaft in an axial flow turbine according to an embodiment of the present invention;

[0039] Figure 7 This is a schematic partial structural diagram of the stator in an axial-flow turbine according to an embodiment of the present invention;

[0040] Figure 8 This is a schematic structural diagram of an axial flow turbine according to an embodiment of the present invention;

[0041] Figure 9 This is a schematic structural diagram of an axial flow turbine according to an embodiment of the present invention. Detailed Implementation

[0042] The following reference Figures 1 to 9This invention describes an axial-flow turbine according to an embodiment of the present invention. In this description, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature, that is, include one or more of that feature. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. When a feature "includes or contains" one or more of the features it encompasses, unless otherwise specifically described, this indicates that other features are not excluded and may be further included.

[0043] Unless otherwise expressly specified and limited, the terms "set," "install," "connect," "link," "fix," and "couple" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art should be able to understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0044] Furthermore, in the description of this embodiment, "above" or "below" the second feature can include direct contact between the first and second features, or it can include contact between the first and second features through another feature between them. That is, in the description of this embodiment, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," or "below" of the second feature can mean the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] In the description of this embodiment, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] Figure 1 This is a schematic structural diagram of an axial-flow turbine according to an embodiment of the present invention, as shown below. Figure 1 As shown, and with reference Figures 2 to 7 This utility model provides an axial flow turbine, which includes a housing, a rotor assembly 20, and two stators 40. A fluid channel is formed within the housing. The housing includes a first housing segment 11, a second housing segment 12, and a third housing segment 13 arranged sequentially along its axial direction; both ends of the second housing segment 12 are detachably connected to the first housing segment 11 and the third housing segment 13, respectively.

[0047] The rotor 20 assembly is located within the housing; the rotor 20 assembly includes a first rotating shaft 30 and a rotor 20; the rotor 20 includes a first sleeve 21 and a plurality of first blades 22 disposed on the outer circumferential surface of the first sleeve 21. The first sleeve 21 is sleeved on the first rotating shaft 30. Two stators 40 are disposed at both ends of the rotor 20 along its axial direction. Each stator 40 includes a second sleeve 41 and a plurality of second blades 42 disposed on the inner circumferential surface of the second sleeve 41; a first housing section 11 is sleeved on the outer circumference of one second sleeve 41, and a third housing section 13 is sleeved on the outer circumference of the other second sleeve 41.

[0048] Specifically, the fluid flowing within the fluid channel can be gas, steam, or water. One end of the first rotating shaft 30 extends to one end opening of the housing, and the other end extends to the other end opening of the housing. The first housing section 11 is interference-fitted to the outer periphery of the second sleeve 41 of the inlet stator 40, and the third housing section 13 is similarly interference-fitted to the outer periphery of the second sleeve 41 of the exhaust stator 40, thereby precisely positioning the two stators 40 within the housing. One end of the first housing section 11 forms a fluid inlet, and the other end of the third housing section 13 forms a fluid outlet. The housing is divided into an inlet section, an expansion section, and an exhaust section.

[0049] Furthermore, the axial-flow turbine of this embodiment can be used in an organic Rankine cycle (ORC) power generation system, thereby replacing existing radial-flow or screw expanders. The fluid flowing in the fluid channel can be R245fa, R1233zd, R1234yf, or HFO-1336mzz-Z working fluid.

[0050] Furthermore, the axial-flow turbine of this embodiment is suitable for heat sources of 90–160°C hot water or steam; the rated speed of the rotor 20 can reach 3000 rpm; the working fluid flow rate inside the casing can reach 0.08 kg / s; and the overall inertia is <0.5 kg·m. 2 Start-up time <30s; energy conversion efficiency is 81.3%, of which the power of the first rotating shaft 30 is 245W and the speed is 3000rpm.

[0051] The working principle of the axial flow turbine is as follows: High-speed flowing fluid enters the fluid channel through the fluid inlet of the first casing section 11, first flowing through the second blade 42 of the inlet stator 40. The fluid is guided and accelerated, impacting the first blade 22 on the rotor 20 at an optimal angle, driving the rotor 20 to rotate at high speed. During this process, the kinetic energy of the fluid is converted into the mechanical energy of the rotor 20. After flowing out of the rotor 20, the fluid flows through the second blade 42 of the exhaust stator 40, restoring its axial flow, and finally exits from the fluid outlet of the third casing section 13, entering the subsequent centrifugal compressor. The rotational mechanical energy of the rotor 20 is output through the first shaft 30, which can be used to drive the centrifugal compressor and generator, further converting the mechanical energy into electrical energy.

[0052] The assembly process of the axial flow turbine is as follows: First, the inlet stator 40 and the first housing section 11, and the exhaust stator 40 and the third housing section 13 are respectively interference-fitted and pre-assembled into two independent stator 40 component modules; then, the outlet stator 40 is sleeved on one end of the first rotating shaft 30; next, the rotor 20 is installed on the first rotating shaft 30, and the second housing section 12 is sleeved on the rotor 20, and the second housing section 12 is fixed together with the first housing section 11 through a detachable structure; then, another stator 40 component module is installed on the other end of the second housing section, and the third housing section is fixed together with the second housing section through a detachable structure.

[0053] This embodiment employs a three-section detachable housing design to modularize the core components of the axial flow turbine, facilitating its assembly, disassembly, and maintenance. When maintenance or replacement of the rotor 20 or stator 40 is required, the second housing section 12 can be separated from the first housing section 11 and the third housing section 13, respectively, thus separating the stator 40 from the rotor 20 and enabling convenient repair of either the rotor 20 or the stator 40. This significantly reduces the traditional 2-3 day disassembly and maintenance time to within one hour, effectively addressing the industry pain point of lengthy turbine assembly and maintenance in existing technologies, and significantly improving the operation and maintenance efficiency, availability, and economy of the ORC power generation system.

[0054] like Figure 1 As shown, in some optional embodiments of this utility model, a first outer flange 111 is provided at one end of the first housing segment 11 near the second housing segment 12; a second outer flange 121 is provided at one end of the second housing segment 12, and a third outer flange 122 is provided at the other end; a fourth outer flange 131 is provided at one end of the third housing segment 13 near the second housing segment 12; the first outer flange 111 and the second outer flange 121 abut against each other and are connected by screws; the fourth outer flange 131 and the third outer flange 122 abut against each other and are connected by screws.

[0055] Specifically, threaded holes are provided on the first outer flange 111 and the second outer flange 121 respectively; threaded holes are provided on the fourth outer flange 131 and the third outer flange 122 respectively.

[0056] The assembly process in this embodiment is as follows: the second outer flange 121 abuts against the first outer flange 111, the third outer flange 122 abuts against the fourth outer flange 131, and screws are used to pass through the corresponding threaded holes for fastening, thereby quickly completing the assembly.

[0057] This embodiment achieves quick assembly and disassembly of the housing and reliable sealing through the design of the outward flange and screw connection. The assembly process does not require on-site welding or complex adjustments, which greatly improves the efficiency of operation and maintenance.

[0058] In some optional embodiments of this utility model, a sealing element is provided between the first outer flange 111 and the second outer flange 121, and between the fourth outer flange 131 and the third outer flange 122.

[0059] Specifically, the material of the seal can be selected according to the chemical properties, temperature and pressure parameters of the working fluid in the fluid channel: for common organic working fluids such as R245fa, EPDM rubber seals can be used.

[0060] In this embodiment, by adding a sealing element, the sealing reliability of the connection interface under high temperature and high pressure conditions is ensured, effectively preventing working fluid leakage and improving the operating efficiency and safety of the axial flow turbine.

[0061] In some optional embodiments of this utility model, the second housing segment and the first housing segment, as well as the second housing segment and the third housing segment, can be connected together by clamps.

[0062] like Figure 3 As shown, in some optional embodiments of this utility model, the connection between the first housing segment 11 and the second housing segment 12 is located at the middle position of the axial direction of a second sleeve 41; the connection between the third housing segment 13 and the second housing segment 12 is located at the middle position of the axial direction of another second sleeve 41.

[0063] For example, the connection between the first outer flange 111 and the second outer flange 121 is located at the middle position of the axial direction of a second sleeve 41; the connection between the fourth outer flange 131 and the third outer flange 122 is located at the middle position of the axial direction of another second sleeve 41.

[0064] In this embodiment, the connection point is located in the middle of the second sleeve 41, which has the best rigidity, essentially fastening it at the "waist" of the stator 40. This location has the highest structural rigidity, and the tightening force will hardly cause deformation of the second sleeve 41, thus helping to maintain the concentricity of the stator 40.

[0065] In the above embodiments, the manufacturing process and materials of the first housing segment 11, the second housing segment 12 and the third housing segment 13 can be flexibly selected according to performance requirements and cost budget.

[0066] Specifically, each shell segment can be manufactured using either traditional CNC milling or additive manufacturing (3D printing). Compared to CNC, 3D printing can improve the manufacturing efficiency of the shell.

[0067] The housing is preferably made of a combination of aluminum alloy and stainless steel. Specifically, the first housing section 11 and the third housing section 13, due to their fixed connection with the stator 40 sleeve, have high requirements for strength and rigidity, and are preferably made of stainless steel to ensure structural stability and durability; while the second housing section 12, as the main covering, is preferably made of aluminum alloy to achieve significant weight reduction. This hybrid material strategy achieves an optimal balance between strength, corrosion resistance, and lightweight.

[0068] like Figure 8 and Figure 9 As shown, in some optional embodiments of the present invention, the axial flow turbine further includes a mounting bracket 50, on which the housing is mounted.

[0069] Specifically, the mounting bracket 50 is provided with at least one set of limiting devices 60. Each set of limiting devices 60 includes an upper limiting plate 61 and a lower limiting plate 62, used to limit the displacement of the housing in the vertical direction. In each set of limiting devices, the positions of the upper limiting plate 61 and the lower limiting plate 62 are adjustable vertically. The upper limiting plate 61 has a first arc-shaped limiting surface adapted to the upper surface of the housing, and the lower limiting plate has a second arc-shaped limiting surface adapted to the lower surface of the housing. For example, one set of limiting devices 60 is installed on the upper and lower sides of the first housing segment 11; another set of limiting devices 60 is provided on the upper and lower sides of the third housing segment 13.

[0070] like Figure 8 and Figure 9 As shown, in some optional embodiments of this utility model, the housing further includes a fourth housing segment 14. The fourth housing segment 14 is detachably disposed on the other side of the first housing segment 11 and communicates with the first housing segment. One end of the first rotating shaft 30 extends to the outside of the first housing segment 11 and into the fourth housing segment 14. The fourth housing segment 14 includes an upper housing segment and a lower housing segment, which are connected by a flange. Specifically, the lower part of the upper housing segment and the upper part of the lower housing segment are both provided with flanges, and the two flanges can be detachably connected by bolts. The other end of the first housing segment 11 is provided with a fifth outward flange, and the end of the fourth housing segment 14 near the first housing segment is provided with a sixth outward flange; the fifth outward flange and the sixth outward flange abut against each other and are connected by screws.

[0071] Furthermore, a set of the aforementioned limiting devices 60 are provided on the upper and lower sides of the fourth housing section 14 to stably install the fourth housing section 14 on the mounting bracket 50.

[0072] like Figure 8 and Figure 9 As shown, in some optional embodiments of this utility model, the mounting bracket 50 is further provided with a bearing seat 51, which is located at the end of the first rotating shaft 30 and is used to support the first rotating shaft 30. In some alternative embodiments, the first rotating shaft can be coaxially and integrally arranged with the second rotating shaft of the centrifugal compressor, in which case the bearing seat on the mounting bracket can be omitted.

[0073] In some optional embodiments of this invention, a wear-resistant layer is provided on the surface of both the first blade 22 and the second blade 42. Specifically, the wear-resistant layer can be prepared by surface treatment methods such as laser cladding or welding.

[0074] In this embodiment, by providing wear-resistant layers on the surfaces of the first blade 22 and the second blade 42, the blades' ability to resist working fluid erosion and particle wear is significantly improved, extending the service life of the stator 40 and the rotor 20. This ensures the stability of aerodynamic efficiency and power output during the long-term operation of the axial flow turbine, while reducing the maintenance frequency and cost caused by wear, thereby effectively improving the operational reliability and economy of the power generation system.

[0075] In some optional embodiments of this utility model, the material of the wear-resistant layer includes one of tungsten carbide, titanium nitride, ceramic matrix composite material, and diamond.

[0076] like Figure 4 and Figure 7 As shown, in some optional embodiments of this utility model, the first blade 22 is a first airfoil blade; the second blade 42 is a second airfoil blade.

[0077] Furthermore, both the first blade 22 and the second blade 42 are NACA65006 airfoil blades optimized for low-temperature operating conditions from 90℃ to 160℃, which can achieve precise matching of aerodynamic performance.

[0078] In this embodiment, the airfoil blade has a good lift-to-drag ratio and flow characteristics at low Reynolds numbers, which can effectively reduce boundary layer separation and secondary flow losses of organic working fluid vapor during the flow process, significantly improve the energy conversion efficiency of the turbine, and thus improve the output power of the entire power generation system.

[0079] In some optional embodiments of this invention, the first blade 22 and the second blade 42 may also adopt a controlled diffusion airfoil (CDA). This airfoil can effectively suppress boundary layer separation and reduce flow losses by optimizing the pressure distribution on the surface, thereby further improving the aerodynamic efficiency of the turbine under high load conditions.

[0080] like Figure 4 and Figure 5 As shown, in some optional embodiments of this utility model, the first sleeve 21 is formed by splicing multiple first sleeve segments 211 along the circumferential direction; each first sleeve segment 211 has a first blade 22 on its outer circumferential surface. Specifically, each first sleeve segment 211 has one or two first blades 22 on its outer circumferential surface, preferably, each first sleeve segment 211 has one first blade 22 on its outer circumferential surface.

[0081] In this embodiment, the above-described configuration achieves modularity of the rotor 20, reducing its manufacturing difficulty and cost. When a local blade is damaged or worn during operation, it is not necessary to replace the entire rotor 20; only the corresponding first sleeve module 211 needs to be replaced, greatly reducing maintenance time and cost.

[0082] like Figure 7 As shown, in some optional embodiments of this utility model, the second sleeve 41 is formed by splicing multiple second sleeve segments 411 circumferentially; each second sleeve segment 411 has a second blade 42 on its inner circumferential surface. Specifically, each second sleeve segment 411 has one or two second blades 42 on its inner circumferential surface, preferably, each second sleeve segment 411 has one second blade 42 on its inner circumferential surface.

[0083] In this embodiment, the above-described configuration achieves modularization of the stator 40 components, significantly reducing the overall manufacturing difficulty and cost of the stator 40. When a specific area of ​​the stator 40 blades is damaged or requires an upgrade, it is not necessary to replace the entire stator 40; only the corresponding second sleeve split module 411 needs to be disassembled and replaced, greatly simplifying the maintenance process and reducing downtime and spare parts costs.

[0084] like Figure 4 , Figure 5 and Figure 7 As shown, in a preferred embodiment of this utility model, the first sleeve 21 is formed by splicing multiple first sleeve segments 211 circumferentially; each first sleeve segment 211 has a first blade 22 on its outer circumferential surface. The second sleeve 41 is formed by splicing multiple second sleeve segments 411 circumferentially; each second sleeve segment 411 has a second blade 42 on its inner circumferential surface.

[0085] In the above three embodiments, the modular structure of the stator 40 and / or rotor 20 facilitates transportation and on-site installation, and allows for the use of differentiated materials or special surface treatments on different components, thereby comprehensively improving the maintainability, economy and design flexibility of the turbine.

[0086] like Figure 4 and Figure 5 As shown, in some optional embodiments of this utility model, each of the two ends of the first sleeve component 211 has a groove 2111. After multiple first sleeve components 211 are spliced ​​together, the multiple grooves 2111 together form an annular groove 212 at each of the two ends of the first sleeve 21. The first rotating shaft 30 includes two stepped shaft segments 31 arranged opposite to each other; each stepped shaft includes a large diameter segment 311 and a small diameter segment 312, and a stepped surface 313 is formed between the large diameter segment 311 and the small diameter segment 312. An annular protrusion 314 is provided on the stepped surface 313. The two stepped shaft segments 31 are configured such that the two small diameter segments 312 are inserted into the first sleeve 21 from both ends, so that each annular protrusion 314 is inserted into the corresponding annular groove 212, and each stepped surface 313 abuts against the corresponding end face of the first sleeve 21.

[0087] During assembly, firstly, the various second sleeve components 411 are spliced ​​around the first rotating shaft 30 at predetermined positions in the circumferential direction, aligning the grooves 2111 on the end faces of each second sleeve component 411. After splicing, an annular groove 212 is formed at each of the axial ends of the first sleeve 21. Then, two stepped shaft segments 31 are inserted into the first sleeve 21 from both ends, facing each other. The smaller diameter segments 312 are inserted deep into the inner hole of the first sleeve 21 until the annular protrusions 314 on the stepped surface 313 of each stepped shaft segment 31 are precisely embedded in the corresponding annular groove 212. At the same time, the stepped surface 313 is in close contact with the corresponding end face of the first sleeve 21, and the ends of the two smaller diameter segments 312 are engaged or magnetically attracted together.

[0088] At this time, the two stepped shaft segments 31, through the engagement of their annular protrusions 314 with the annular grooves 212 and the axial abutment of the stepped surfaces 313, together form a powerful axial locking mechanism, which firmly clamps and positions all the first sleeve segments 211 on the rotating shaft.

[0089] In this embodiment, the precise alignment of the rotor assembly on the shaft is automatically achieved through the cooperation of the annular protrusion 314 and the annular groove 212. Furthermore, the assembly and disassembly processes are simple and direct; when it is necessary to replace a section of the blade, simply separating the two stepped shaft sections 31 allows for the replacement of a single "blade-second sleeve split" module, greatly simplifying the maintenance process. Additionally, this axial clamping method generates a more uniform stress distribution, avoiding the impact of localized stress concentration on the accuracy and lifespan of the rotor 20.

[0090] In some optional embodiments of this utility model, each first sleeve segment 211 has a first mounting portion extending radially outward at its circumferential end, and the first mounting portion has a threaded hole. During assembly, the first mounting portions of two adjacent first sleeve segments 211 are fitted together and aligned with the holes. Bolts are passed through the first mounting portions and nuts are tightened, thereby fastening all the first sleeve segments 211 together to form a complete rotor 20 structure.

[0091] like Figure 7 As shown, in some optional embodiments of the present invention, each second sleeve split 411 has a plug-in portion 4111 at one end in the circumferential direction and a plug-in groove 4112 at the other end; the plug-in portion 4111 of the second sleeve split 411 is inserted into the plug-in groove 4112 of the adjacent second sleeve split 411.

[0092] This embodiment achieves rapid and precise splicing of the stator 40 components by providing a plug-in part 4111 and a plug-in slot 4112 on each second sleeve split 411.

[0093] In some optional embodiments of this utility model, each second sleeve component 411 has a second mounting portion extending radially inward at its circumferential end, and the second mounting portion has a threaded hole. During assembly, the second mounting portions of two adjacent second sleeve components 411 are fitted together and aligned with the holes. Bolts are passed through the second mounting portions and nuts are tightened, thereby fastening all the second sleeve components 411 together into a complete stator structure.

[0094] An embodiment of this utility model also provides an ORC power generation system, which includes a centrifugal compressor and an axial-flow turbine as described in any of the above embodiments. The centrifugal compressor has a second shaft.

[0095] In some embodiments, the first rotating shaft 30 is drive-connected to the second rotating shaft.

[0096] In other embodiments, the first rotating shaft 30 and the second rotating shaft are integrally formed coaxially. Compared with a separate structure for the first rotating shaft 30 and the second rotating shaft, the integral formation of the first rotating shaft 30 and the second rotating shaft can reduce the number of couplings and bearing seats by 2, resulting in a 30% reduction in volume.

[0097] In some embodiments, the ORC power generation system further includes a generator disposed between the centrifugal compressor and the axial turbine. The generator includes a third shaft.

[0098] Furthermore, the first rotating shaft 30, the third rotating shaft, and the second rotating shaft are sequentially connected for transmission. Alternatively, the first rotating shaft 30, the second rotating shaft, and the second rotating shaft are coaxially integrally formed.

[0099] In some optional embodiments of this invention, the ORC power generation system further includes a preheater, a condenser, and a working fluid pump.

[0100] When the ORC power generation system is working, the working fluid flows as follows: heat source → preheater → axial turbine → centrifugal compressor → condenser → liquid storage tank → working fluid pump → preheater, forming a closed loop.

[0101] Therefore, those skilled in the art should recognize that although many exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all such other variations or modifications.

Claims

1. An axial-flow turbine, characterized in that, include: A housing having a fluid channel formed within it; the housing includes a first housing segment, a second housing segment, and a third housing segment arranged sequentially along its axial direction; both ends of the second housing segment are detachably connected to the first housing segment and the third housing segment, respectively. A rotor assembly is located within the housing; the rotor assembly includes a first rotating shaft and a rotor; the rotor includes a first sleeve and a plurality of first blades disposed on the outer circumferential surface of the first sleeve; the first sleeve is sleeved on the first rotating shaft; Two stators are disposed at both ends of the rotor along its axial direction. Each stator includes a second sleeve and a plurality of second blades disposed on the inner circumferential surface of the second sleeve. A first housing segment is sleeved on the outer circumference of one of the second sleeves, and a third housing segment is sleeved on the outer circumference of the other second sleeve.

2. The axial-flow turbine according to claim 1, characterized in that, The first housing segment has a first outward flange at one end near the second housing segment; One end of the second housing segment is provided with a second outward flange, and the other end is provided with a third outward flange; The third housing segment is provided with a fourth outward flange at one end near the second housing segment; The first outward flange and the second outward flange abut against each other and are connected by screws; The fourth outer flange abuts against the third outer flange and is connected by screws.

3. The axial-flow turbine according to claim 2, characterized in that, A sealing element is provided between the first outer flange and the second outer flange, and between the fourth outer flange and the third outer flange.

4. The axial-flow turbine according to claim 1, characterized in that, The connection between the first housing segment and the second housing segment is located at the midpoint of the axial direction of the second sleeve; The connection between the third housing segment and the second housing segment is located at the midpoint of the axial direction of another second sleeve.

5. The axial-flow turbine according to claim 1, characterized in that, Both the first blade and the second blade have a wear-resistant layer on their surfaces; The wear-resistant layer is made of one of the following materials: tungsten carbide, titanium nitride, ceramic matrix composite material, and diamond.

6. The axial-flow turbine according to claim 1, characterized in that, The first blade is a first airfoil blade; the second blade is a second airfoil blade.

7. The axial-flow turbine according to claim 1, characterized in that, The first sleeve is assembled circumferentially from multiple first sleeve segments; each first sleeve segment has the first blade disposed on its outer circumferential surface; and / or The second sleeve is composed of multiple second sleeve segments spliced ​​together circumferentially; each second sleeve segment has a second blade on its inner circumferential surface.

8. The axial-flow turbine according to claim 7, characterized in that, Each of the first sleeve components has grooves on both ends of its axial direction. When multiple first sleeve components are spliced ​​together, the multiple grooves together form an annular groove at both ends of the first sleeve. The first rotating shaft includes two stepped shaft segments arranged opposite each other; each stepped shaft includes a large diameter segment and a small diameter segment, and a stepped surface is formed between the large diameter segment and the small diameter segment, and an annular protrusion is provided on the stepped surface; the two stepped shaft segments are configured such that the two small diameter segments are inserted into the first sleeve from both ends, so that each annular protrusion is inserted into the corresponding annular groove, and each stepped surface abuts against the corresponding end face of the first sleeve.

9. The axial-flow turbine according to claim 7, characterized in that, Each of the second sleeve components has a plug-in part at one end of its circumference and a plug-in groove at the other end; The insertion part of the second sleeve component is inserted into the insertion slot of the adjacent second sleeve component.

10. A power generation system, characterized in that, include: The axial flow turbine as described in any one of claims 1 to 9; A centrifugal compressor having a second rotating shaft; the first rotating shaft is drivingly connected to the second rotating shaft, or the first rotating shaft and the second rotating shaft are coaxially integrally formed.

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