A nuclear power steam generator-based steam-water separator exhaust structure

Abstract

The application discloses a steam-water separator steam exhaust structure based on a nuclear power steam generator and relates to the technical field of steam-water separation in steam generators. The steam-water separator steam exhaust structure comprises a steam generator cylinder, and a cyclone separation module is arranged in the steam generator cylinder. The cyclone separation module is composed of a plurality of lower connection cylinders and upper connection cylinders, and the two cylinders cooperatively form a multilayer surrounding structure, which is suitable for the cylindrical cavity layout of the steam generator cylinder. When steam-water mixture flows through the cyclone separation module, the steam-water mixture sequentially passes through the lower connection cylinders and the upper connection cylinders, forming a two-stage continuous and function-differentiated separation process. Through the two-stage separation, the steam-water mixture is first coarsely separated by the lower connection cylinders in the first step, and most of the water is preliminarily removed. Then, the upper connection cylinders coarsely separate the residual trace water droplets in the second step. The two-stage process is closely connected and has different focuses, thereby avoiding the problem of incomplete separation caused by the cyclone attenuation in a single separation stage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steam-water separation in steam generators, in particular to a steam-water separator steam exhaust structure based on a nuclear power steam generator. BACKGROUND

[0002] The steam-water separator steam exhaust structure in the prior art is essentially a key subsystem designed for the steam-water separator in the nuclear power steam generator for efficiently exhausting qualified steam after separation. The core purpose of its existence is to ensure the steam quality and safety of the nuclear power secondary circuit, so that the water content of the separated steam needs to meet the nuclear power standard, usually requiring a dryness of > 99.9%, to avoid water droplets impacting turbine blades and causing damage, and ultimately to provide stable power for the turbine.

[0003] However, the prior art still has the following defects in specific use: 1. In a nuclear power steam generator, the cyclone separator in the prior art is mostly in the form of a cylindrical array, with the inlet guide vanes concentratedly arranged at the lower or middle-lower inlet section of the cylinder. From the operating principle, the steam-water mixture needs to be forcibly guided by the guide vanes to form a rotational flow to generate centrifugal force for separation. However, in actual operation, since the power of the rotational flow completely depends on the initial guidance of the inlet section guide vanes, during the high-speed spiral upward movement of the steam-water mixture along the inner wall of the cylinder, it will continuously be subjected to frictional resistance of the cylinder wall, viscous resistance between steam and water, and kinetic energy loss of steam flowing upward, resulting in a continuous weakening of the rotational flow intensity with the increase of the upward distance. Therefore, when the mixture approaches the upper outlet of the cylinder, the centrifugal force generated by the initial rotational flow has been greatly reduced, and it cannot effectively separate the remaining steam and water, thereby causing the defect of weakened separation effect at the outlet.

[0004] This weakened separation effect at the outlet can cause part of the wet steam that has not been fully separated to directly enter the upper wave-shaped plate dryer, significantly increasing the processing load of the dryer. Not only does this shorten the service life of the dryer, but it can also cause the drying effect to decrease due to overload, affecting the final steam quality. In addition, the water that has not been fully separated can also form a water hammer phenomenon in the steam pipeline, causing impact damage to the pipeline and related equipment, increasing the maintenance cost and safety risk of the overall system of the nuclear power steam generator.

[0005] 2. Meanwhile, the inner wall of the cyclone separator cylinder is mostly designed with a smooth surface. The original intention of this design is to reduce fluid flow resistance and facilitate the formation of a stable spiral flow of steam-water mixture. However, in the actual separation process, this smooth surface has the defect of being hydrophobic and easily rolled up again: when dense water is thrown towards the cylinder wall by centrifugal force, it will form a continuous "water film" on the smooth wall surface. Since the adhesion between the smooth wall surface and the water is weak, and the steam always flows upward along the cylinder wall in a spiral motion, it will exert a continuous upward drag force on the water film on the wall surface. Therefore, when the steam flow rate increases due to load fluctuations, the drag force will be greater than the weight of the water film itself and the adhesion of the wall surface, causing some of the water film to be carried upward by the steam and re-mixed into the steam in the central area, destroying the separation effect that has been formed.

[0006] This directly reduces the dryness of the steam. Incompletely separated moisture enters the subsequent system with the steam, which will aggravate water erosion damage to the turbine blades. Furthermore, the re-entrained moisture may be entrained with the steam at the upper outlet of the cylinder, causing a sudden increase in the wet steam load entering the secondary dryer, exceeding the dryer's design capacity and further reducing the final steam quality.

[0007] 3. Furthermore, in the existing technology, the guide vanes inside the cyclone separator are designed in a fixed form. Their core function is to guide the steam-water mixture to form a spiral motion, rather than actively driving the fluid to rotate. This passive guiding structure has poor adaptability to changes in steam velocity. When the equipment is in peak production and the load is frequently adjusted, the steam velocity entering the separator will fluctuate significantly, causing the Reynolds number of the fluid flow to exceed the stable range. The originally regular spiral flow field is broken, forming strong turbulence. Since the fixed vanes cannot adjust the guiding angle or intensity according to the velocity change, they cannot suppress the generation of turbulence. As a result, the liquid water that has been separated to the cylinder wall by centrifugal force is re-rolled up by the turbulence and mixed into the steam again, ultimately causing the separation efficiency to decrease and the steam dryness to decrease.

[0008] When turbulence occurs, firstly, it reduces the working efficiency of the steam turbine, affecting the power generation economy of the entire nuclear power system; secondly, insufficiently separated moisture may accumulate in the steam pipes, causing water hammer, which can cause impact damage to pipes, valves and other equipment, and in severe cases may even lead to pipe rupture; thirdly, in order to maintain steam quality, it is necessary to increase the operating load of the subsequent drying unit, which not only increases the equipment maintenance cost, but may also cause new failure risks due to the long-term high-load operation of the drying unit.

[0009] Therefore, in view of this, the present invention proposes a steam-water separator exhaust structure based on a nuclear power steam generator to make up for and improve the shortcomings of the prior art. Summary of the Invention

[0010] To solve the above technical problems, the application provides a steam-water separator steam exhaust structure based on a nuclear power steam generator to solve the technical problems in the background art.

[0011] To achieve the above object, the application adopts the technical scheme of a steam-water separator steam exhaust structure based on a nuclear power steam generator, comprising a steam generator cylinder, the inside of the steam generator cylinder is equipped with a cyclone separation module, the cyclone separation module is composed of a plurality of lower connection cylinders and upper connection cylinders, both of which cooperatively form a multi-layer surrounding structure, which is suitable for the cylindrical cavity layout of the steam generator cylinder.

[0012] When the steam-water mixture generated inside the steam generator cylinder flows through the cyclone separation module, it will pass through the lower connection cylinder and the upper connection cylinder in turn and complete two continuous and functionally differentiated separation processes: first, the steam-water mixture enters the inside of the lower connection cylinder with a steeper slope, uses the steeper wall to quickly accelerate the cyclone, avoids the dispersion of the initial stage cyclone, and realizes the first step of steam-water coarse separation; then, the mixture after coarse separation enters the upper connection cylinder with a gentler slope, prolongs the cyclone path through the gentle wall, guarantees the persistence of the centrifugal separation effect, and reduces the steam flow rate, thereby reducing the probability of small water droplets being carried out.

[0013] Further, the lower connection cylinder and the upper connection cylinder are designed in a funnel shape with the upper part being wide and the lower part being narrow, and the upper end surface area of the lower connection cylinder is equal to the lower end surface area of the upper connection cylinder, both of which are assembled in a segmented one-piece manner, wherein the inclination slope of the lower connection cylinder is greater than that of the upper connection cylinder, and the separation efficiency is improved through the synergistic effect of different steep slopes.

[0014] Further, the cyclone separation module further comprises a bearing chassis, the bearing chassis is assembled inside the steam generator cylinder and is designed in an integrated manner with the multi-layer surrounding structure composed of a plurality of lower connection cylinders and upper connection cylinders, and the lower surface of the bearing chassis is uniformly fixedly connected with an isolation edge layer.

[0015] Further, in the multi-layer surrounding structure composed of the lower connection cylinder and the upper connection cylinder, the isolation edge layer is located between the adjacent two layers, and the outer wall of the isolation edge layer is symmetrically chamfered.

[0016] Further, the input end of the lower connection cylinder is internally provided with a fixed clasp, the outer wall of the fixed clasp is uniformly fixedly connected with a plurality of tooth protrusions, the fixed clasp is fixedly connected with the inner wall of the lower connection cylinder through the tooth protrusions, and the connection position is further provided with a gap space formed by adjacent tooth protrusions.

[0017] Further, the inner wall of the fixed buckle ring is fixedly connected with a rotational flow guide, the upper surface of the rotational flow guide is fixedly connected with a sliding surface penetrating shaft, the sliding surface penetrating shaft adopts a hollow structure, and an internal power supply wire is arranged to regulate the working state of the rotational flow guide, and the inclination angle of the external blade of the rotational flow guide is dynamically adjusted through the electric signal transmitted by the wire.

[0018] Further, the sliding surface penetrating shaft is divided into upper and lower sections along the axial direction, the lower section is completely embedded in the inner part of the lower connecting cylinder, and the upper section is completely embedded in the inner part of the upper connecting cylinder; the diameter of the upper section of the sliding surface penetrating shaft is greater than that of the lower section, and the boundary position of the upper and lower sections is accurately aligned with the slope transition boundary of the lower connecting cylinder and the upper connecting cylinder.

[0019] Further, the inner wall of the lower connecting cylinder is provided with a spiral lower flow guide groove, and the inner side of the lower flow guide groove is fixedly connected with a spiral lower reinforcing rib; the inner wall of the upper connecting cylinder is provided with a spiral upper flow guide groove, and the inner side of the upper flow guide groove is fixedly connected with a spiral upper reinforcing rib.

[0020] Further, the distribution density of the lower flow guide groove and the lower reinforcing rib is higher than that of the upper flow guide groove and the upper reinforcing rib; and the spiral directions of the four are consistent with the fluid rotational flow direction of the steam-water mixture in the separation process, so that the separated hydrophobic substance is guided to flow downward along the spiral path, effectively avoiding the problem of secondary entrainment of hydrophobic substance by steam.

[0021] Further, the steam generator cylinder is internally provided with a steam-water separator assembly, the steam-water separator assembly comprises a steam collecting cavity module and a wave-shaped plate separation module, and the steam collecting cavity module, the wave-shaped plate separation module and the cyclone separation module are arranged in an up-down distribution and located on the same axial line; the steam-water mixture sequentially passes through the cyclone separation module and the wave-shaped plate separation module, the separated dry steam is uniformly introduced into the steam collecting cavity module, thereby stabilizing the steam flow field, allowing the steam to stay in the cavity for a short time, and further removing residual small water droplets.

[0022] Compared with the prior art, the present application has the following advantages: (1) In order to overcome the defects of the prior art that the cyclone separator only relies on the initial guiding of the inlet section guide vane and the decay of the rotational flow intensity with the rising distance, the device makes the steam-water mixture flow through the cyclone separation module in turn through the lower connecting cylinder and the upper connecting cylinder, forming a two-stage continuous and function-differentiated separation process. Specifically, through two-stage separation, the first step of steam-water coarse separation is completed by the lower connecting cylinder to preliminarily remove most of the water, and the second step of coarse separation is performed by the upper connecting cylinder for the residual trace water droplets. The two-stage process is closely linked and each has its own focus, avoiding the problem of incomplete separation caused by the decay of rotational flow in a single separation stage. This way not only ensures the continuity of the separation process, but also allows each stage of separation to focus on the core needs under the corresponding working conditions through function differentiation, greatly improving the overall separation efficiency, reducing the wet steam load entering the subsequent wave plate separation module, avoiding overloading of the dryer, reducing the risk of water hammer in the steam pipeline and system maintenance costs, while ensuring the stability of the final steam quality.

[0023] The device realizes the synergistic effect of different steep slopes through the differentiated design of the lower connecting cylinder with a larger slope than the upper connecting cylinder. Specifically, the lower connecting cylinder with a steeper slope can quickly accelerate the rotational flow using the steeper wall surface to provide sufficient and stable initial rotational flow kinetic energy for the steam-water mixture, effectively avoiding the problem of dispersed rotational flow in the initial stage, ensuring the rapid establishment of centrifugal force and efficiently completing the first step of coarse separation, solving the defects of insufficient initial guiding and weak rotational flow intensity in the prior art. Then, the mixture after the first step of coarse separation enters the upper connecting cylinder with a gentler slope. The gentle wall surface on the one hand prolongs the rotational flow path, allowing the rotational flow to act on the residual trace water droplets for a longer time, ensuring the persistence of the centrifugal separation effect and making up for the deficiency of the prior art that the rotational flow decays with the rising distance. On the other hand, it reduces the steam flow rate, reduces the entrainment force of the steam on the small water droplets, and avoids the problem of water droplets being carried out due to high flow rate, further improving the separation precision and reducing the water content entering the subsequent system.

[0024] Compared with the smooth inner wall and constant cross-section of the cylindrical structure in the prior art, the device has the defect that the hydrophobic layer is re-coiled. In the present application, both the lower connecting cylinder and the upper connecting cylinder adopt a funnel-shaped structure with a wide upper part and a narrow lower part, and the upper end surface area of the lower connecting cylinder is equal to the lower end surface area of the upper connecting cylinder, assembled in a segmented one-piece manner. First, the wide upper part and narrow lower part gradually allow the steam to enter a wider space during the rising process, gradually reducing the flow rate and reducing the drag force on the wall hydrophobic layer, avoiding the re-coiling of the water film. At the same time, the equal end surface area ensures smooth transition of the flow field at the junction of the two connecting cylinders, avoiding obvious turbulent disturbance and ensuring the stability of the rotational flow.

[0025] (2) In the actual separation process, for the water droplets thrown to the wall surface after separation, the spiral lower guide groove on the inner wall of the lower connecting cylinder and the spiral lower reinforcing rib at the lower edge thereof, and the spiral upper guide groove on the inner wall of the upper connecting cylinder and the spiral upper reinforcing rib at the lower edge thereof, form directional guidance for the hydrophobic through the spiral design consistent with the fluid cyclone direction. Specifically, the guide groove can directly collect the water droplets into the groove, guide the hydrophobic to flow downward through the spiral path, avoid the water droplets from diffusing randomly on the wall surface, and the reinforcing rib further blocks the upward wrapping of steam on the hydrophobic, forming a synergistic effect of groove collection and rib blocking. At the same time, the distribution density of the lower guide groove and the reinforcing rib is higher than that of the upper guide groove and the reinforcing rib, which adapts to the working condition difference of the separation process. The lower connecting cylinder is the first stage of coarse separation, and the water droplet content is high, so the high-density structure can quickly and efficiently handle a large amount of hydrophobic. The upper connecting cylinder processes residual trace water droplets, and the low-density structure can meet the hydrophobic guiding requirement and avoid excessive setting interference with the steam flow field. This density differentiated spiral structure design not only ensures that the hydrophobic can be stably guided to flow back in the whole process, completely eliminating the risk of secondary entrainment, but also reduces the fluid resistance while improving the hydrophobic efficiency by adapting to the water droplet content in different separation stages. The density differentiated spiral structure design is complementary to the two-stage slope design, further improving the overall separation efficiency.

[0026] The fixed buckle ring forms a gap space for the hydrophobic to flow out through the circumferential teeth protrusions on the outer wall, and the hydrophobic outlet is staggered with the steam inlet of the cyclone guide, forming a dry and wet separation layout, which avoids excessive collision and mixing of the hydrophobic backflow with the newly incoming steam-water mixture, ensures the accurate guiding effect of the cyclone guide on the initial cyclone, and prevents the hydrophobic from accumulating in the cylinder to cause flow field disorder, further maintaining the stability of the cyclone.

[0027] (3) In the actual separation process, for the steam flowing after being gathered after separation, the segmented design of the sliding surface through shaft is adapted to the structure of the connecting cylinder. The design that the upper segment is larger in diameter than the lower segment forms a functional synergy with the slope difference of the two-stage connecting cylinder: the smaller diameter of the lower segment is adapted to the steep slope of the lower connecting cylinder, reserving sufficient peripheral space for the initial high-speed cyclone, avoiding hindering the strong cyclone just formed; the larger diameter of the upper segment is suitable for the gentle slope of the upper connecting cylinder, expanding the central area space to reduce the flow resistance of the steam rising, and providing more stable guidance for the steam with reduced flow rate after coarse separation, reducing vortex generation. This structure matching not only strengthens the guiding effect on the cyclone in different stages, but also makes the steam maintain orderly flow in the whole rising process through the synchronous connection of the diameter change and the slope change, further improving the separation efficiency and avoiding the cyclone disorder caused by unreasonable central area structure. This structure matching cooperates with structures such as guide grooves and ribs to jointly ensure the stability of the separation effect.

[0028] (4) The device can dynamically adjust the angle of the blade through the cyclone guide part, and can dynamically adjust the inclination angle of the blade according to the real-time flow and pressure of the steam-water mixture, in combination with the regulation and control function of the slide surface through shaft embedded wire, so as to effectively improve the poor adaptability of the existing fixed guide vane to flow velocity fluctuation. When the steam flow fluctuates due to equipment load adjustment, the dynamically adjusted blade can make the mixture always enter the cavity at the optimal tangential velocity, prevent the liquid water separated to the cylinder wall from being rolled up again, not only stabilize the separation efficiency and guarantee the steam dryness, but also avoid the steam turbine work efficiency caused by turbulence, reduce the steam pipeline water hammer risk, reduce the subsequent drying device operation load, save maintenance cost, avoid the fault hidden danger caused by high load operation, and adapt to the load fluctuation working condition demand of nuclear power system. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a three-dimensional structure schematic diagram of the existing nuclear power steam generator steam-water separator assembly.

[0030] Figure 2 It is a plane schematic diagram of the internal structure of the existing nuclear power steam generator steam-water separator assembly.

[0031] Figure 3 It is a three-dimensional structure schematic diagram of the nuclear power steam generator steam-water separator assembly in the application.

[0032] Figure 4 It is a plane schematic diagram of the internal structure of the nuclear power steam generator steam-water separator assembly in the application.

[0033] Figure 5 It is a three-dimensional structure schematic diagram of the cyclone separation module in the application.

[0034] Figure 6 It is a plane schematic diagram of the internal structure of the lower connecting cylinder and the upper connecting cylinder in the application.

[0035] Figure 7 It is a three-dimensional structure schematic diagram of the guide vane position relationship in the application.

[0036] Figure 8 It is a three-dimensional structure schematic diagram of the guide vane in different operating states in the application.

[0037] Figure 9 It is a three-dimensional structure schematic diagram of the lower and upper reinforcing ribs in the application.

[0038] Figure 10 It is a plane schematic diagram of the position relationship structure of the upper and lower reinforcing ribs and the guide groove in the application.

[0039] The figure marks are: 1, steam generator cylinder; 2, steam-water separator assembly; 3, steam collecting cavity module; 4, wave plate separation module; 5, cyclone separation module; 51, bearing chassis; 52, isolation edge layer; 53, lower connecting cylinder; 54, fixed buckle; 55, cyclone guide; 56, sliding surface through shaft; 57, lower guide groove; 58, lower reinforcing rib; 59, upper connecting cylinder; 510, upper guide groove; 511, upper reinforcing rib. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0041] It should be noted that the structure and working principle of the steam generator cylinder 1, the steam-water separator assembly 2, the steam collecting cavity module 3, the wave plate separation module 4 and the like belong to the prior art, and will not be described here.

[0042] Embodiment 1: Please refer to Figure 1 Figure 10 A steam-water separator steam exhaust structure based on a nuclear power steam generator, as shown in the figure, comprises a steam generator cylinder 1, and a cyclone separation module 5 is arranged in the steam generator cylinder 1. The cyclone separation module 5 is composed of a plurality of lower connecting cylinders 53 and upper connecting cylinders 59, and the two together form a multi-layer surrounding structure, which is suitable for the cylindrical cavity layout of the steam generator cylinder 1.

[0043] It should be noted that the steam generator cylinder 1 is internally provided with a steam-water separator assembly 2, the steam-water separator assembly 2 comprises a steam collecting cavity module 3 and a wave plate separation module 4, and the steam collecting cavity module 3, the wave plate separation module 4 and the cyclone separation module 5 are arranged in a vertical distribution and located on the same axis. The steam-water mixture passes through the cyclone separation module 5 and the wave plate separation module 4 in sequence, the separated dry steam is uniformly collected into the steam collecting cavity module 3, thereby stabilizing the steam flow field, and the steam is temporarily retained in the cavity, further removing the residual small water droplets.

[0044] Please refer to Figure 1 Figure 10 ​​As shown, when the steam-water mixture generated inside the steam generator cylinder 1 flows through the cyclone separation module 5, it will pass through the lower connecting cylinder 53 and the upper connecting cylinder 59 in turn, and complete two continuous and functionally differentiated separation processes: first, the steam-water mixture enters the lower connecting cylinder 53 with a steep slope, uses the steep wall to quickly accelerate the cyclone, avoids the dispersion of the initial stage cyclone, realizes the first step of steam-water separation, and then the mixture after rough separation enters the upper connecting cylinder 59 with a gentle slope, prolongs the cyclone path through the gentle wall, guarantees the persistence of the centrifugal separation effect, and reduces the steam flow rate, thereby reducing the probability of small water droplets being carried out.

[0045] It should be noted that the lower connecting cylinder 53 and the upper connecting cylinder 59 are designed in a funnel shape with the upper part being wide and the lower part being narrow, and the upper end surface area of the lower connecting cylinder 53 is equal to the lower end surface area of the upper connecting cylinder 59. They are assembled in a segmented and integrally formed manner, wherein the inclination slope of the lower connecting cylinder 53 is greater than that of the upper connecting cylinder 59, and the different steep slopes work together to improve the separation efficiency.

[0046] Please refer to Figure 1 - Figure 10 As shown, the cyclone separation module 5 further comprises a bearing bottom plate 51, which is assembled inside the steam generator cylinder 1 and is designed in an integrated manner with the multi-layered surrounding structure formed by the lower connecting cylinders 53 and the upper connecting cylinders 59. The lower surface of the bearing bottom plate 51 is uniformly fixedly connected with a separation edge layer 52. In the multi-layered surrounding structure formed by the lower connecting cylinders 53 and the upper connecting cylinders 59, the separation edge layer 52 is located between the adjacent two layers. The outer wall of the separation edge layer 52 is symmetrically chamfered. The input end of the lower connecting cylinder 53 is internally provided with a fixed clasp 54. The outer wall of the fixed clasp 54 is uniformly fixedly connected with a plurality of tooth protrusions. The fixed clasp 54 is fixedly connected with the inner wall of the lower connecting cylinder 53 through the tooth protrusions, and the connection position is further provided with a gap space formed by the adjacent tooth protrusions. The inner wall of the fixed clasp 54 is fixedly connected with a cyclone guide 55. The upper surface of the cyclone guide 55 is fixedly connected with a sliding surface penetrating shaft 56. The sliding surface penetrating shaft 56 adopts a hollow structure and is internally provided with an electrically conductive wire for controlling the working state of the cyclone guide 55. The electric signal transmitted through the wire drives the external blades of the cyclone guide 55 to realize dynamic adjustment of the inclination angle.

[0047] It should be noted that the sliding surface through shaft 56 is divided into upper and lower two sections in the axial direction, the lower section is completely fitted and embedded in the inside of the lower connecting cylinder 53, and the upper section is completely fitted and embedded in the inside of the upper connecting cylinder 59; and the diameter size of the upper section of the sliding surface through shaft 56 is larger than that of the lower section, and the boundary position of the upper and lower two sections is accurately aligned with the slope transition boundary of the lower connecting cylinder 53 and the upper connecting cylinder 59. The inner wall of the lower connecting cylinder 53 is provided with a spiral lower flow guide groove 57, and the inner side of the lower flow guide groove 57 is fixedly connected with a spiral lower reinforcing rib 58 at the lower edge position corresponding to the lower flow guide groove 57. The inner wall of the corresponding upper connecting cylinder 59 is provided with a spiral upper flow guide groove 510, and the inner side of the upper flow guide groove 510 is fixedly connected with a spiral upper reinforcing rib 511 at the lower edge position corresponding to the upper flow guide groove 510. The distribution density of the lower flow guide groove 57 and the lower reinforcing rib 58 is higher than that of the upper flow guide groove 510 and the upper reinforcing rib 511; and the spiral directions of the four are consistent with the fluid cyclone direction of the steam-water mixture in the separation process, so that the separated hydrophobic substance is guided to flow downward along the spiral path, effectively avoiding the problem of secondary entrainment of hydrophobic substance by steam.

[0048] Specifically, during the operation of the nuclear steam generator, the steam flow rate is high (usually up to dozens of meters per second), and the pressure is stable.

[0049] The running process of the steam-water mixture in the lower connecting cylinder 53: when the steam-water mixture generated in the steam generator cylinder 1 enters the cyclone separation module 5, it first enters the cavity of the lower connecting cylinder 53 through the rotational flow guide 55 of the inner wall of the lower connecting cylinder 53. The fixed buckle ring 54 input end adopts a funnel-shaped structure with a wide upper part and a narrow lower part and a steep inclination, and the steep wall further strengthens the acceleration effect of the rotational flow, avoids the attenuation of the rotational flow intensity when the mixture just enters due to the flow field diffusion, and guarantees the rapid establishment of the centrifugal force. Under the action of the centrifugal force, the water droplets with large density are quickly thrown to the inner wall of the lower connecting cylinder 53, and the steam with small density is gathered to the center of the cavity, which preliminarily realizes the first step of steam-water rough separation.

[0050] Meanwhile, the helical lower guide groove 57 on the inner wall of the lower connecting cylinder 53 and the helical lower reinforcing rib 58 corresponding to the lower edge work together: the lower guide groove 57 provides a directional flow channel for the water droplets thrown to the wall surface, avoiding the secondary diffusion caused by the random flow of water droplets on the wall surface; the lower reinforcing rib 58, on the one hand, further guides the rotational flow direction and maintains the stability of the rotational flow, and on the other hand, blocks the water droplets from being re-entrained by the central steam; finally, the separated water droplets flow downward along the lower guide groove 57, flow out of the lower connecting cylinder 53 through the gap formed by the tooth protrusions on the outer wall of the fixed buckle 54, avoid the inlet and outlet shunt of the steam inlet of the rotational flow guide 55 of the steam-water mixture, and cause the dry and wet fluids to interfere with each other, and then flow back to the lower part of the steam generator cylinder 1 to reheat; and the central gathered steam continues to spiral upward under the central guiding effect of the rotational inertia and the lower section of the slide-through shaft 56, laying a foundation for fine separation into the upper connecting cylinder 59, which is consistent with the "first coarse separation and then fine separation" logic of the existing steam-water separator assembly 2, and through the cooperation of dynamic flow guiding and steep wall acceleration, the efficiency and stability of the coarse separation stage are improved.

[0051] The running process of the steam-water mixture in the upper connecting cylinder 59: the steam that has completed the first step of coarse separation in the lower connecting cylinder 53 still carries a small amount of tiny water droplets, continues to spiral upward into the upper connecting cylinder 59, as shown in Figure 6 The upper connecting cylinder 59 is also a funnel-shaped structure with a wide upper part and a narrow lower part, but the inclination slope is relatively gentle compared to the lower connecting cylinder 53, and the upper section of the slide-through shaft 56 is completely embedded in the upper connecting cylinder 59, with the diameter of the upper section being larger than that of the lower section, and the boundary position is accurately aligned with the slope transition boundary of the lower connecting cylinder 53 and the upper connecting cylinder 59.

[0052] The gentle wall design prolongs the rotational flow path of the steam in the cavity, slows down the axial upward speed of the steam, avoids the rapid entrainment of a small amount of water droplets due to excessive flow speed, and the diameter of the upper section of the slide-through shaft 56 is increased, which provides a more stable guiding channel for the central steam, and also reduces the resistance to steam flow by expanding the central area space, reducing vortex generation, and at the same time, as shown in Figure 10 The helical upper guide groove 510 on the inner wall of the upper connecting cylinder 59 and the helical upper reinforcing rib 511 corresponding to the lower edge are lower in distribution density than the lower structure, which is suitable for the working condition of reduced water droplet content in the steam, and continues the spiral design consistent with the rotational flow direction of the fluid to capture the tiny water droplets remaining in the steam for the second time: the tiny water droplets are thrown to the inner wall under the action of continuous centrifugal force, flow downward along the upper guide groove 510, flow back to the lower connecting cylinder 53 through the connection between the lower connecting cylinder 53 and the upper connecting cylinder 59, and finally flow out through the tooth gap of the fixed buckle 54; the upper reinforcing rib 511 assists in maintaining the stability of the rotational flow, avoiding the turbulent flow of steam flow field causing the captured water droplets to escape again.

[0053] After the rough separation of the second step through the upper connecting cylinder 59, the steam dryness is greatly improved, and then enters the wave plate separation module 4 of the steam-water separator assembly 2. This link completely integrates the wave plate separation process after the existing cyclone separation. The wave plate separation module 4 uses the impact and interception of multiple layers of wave plates to capture the remaining small diameter water droplets in the steam, further improving the steam dryness, and finally ensuring that the dry steam meeting the dryness requirement flows into the steam collection cavity module 3. The steam collection cavity module 3 stabilizes the steam flow field by uniformly collecting the steam discharged from multiple cyclone separation modules 5, and allows the steam to stay in the cavity for a short time, so that the remaining trace amount of small water droplets are further removed by gravity settling or cavity wall condensation, ensuring stable steam quality output to the steam turbine, and completing the entire steam-water separation and steam exhaust process.

[0054] The gentle slope design of the upper connecting cylinder 59 and the low-density guide / rib structure not only adapts to the working condition requirement of low steam water droplet content after the first rough separation step, but also realizes the dual compatibility of separation efficiency and existing technology process through seamless connection with the wave plate separation module 4.

[0055] When the device is in the production peak period of frequent load adjustment, the flow rate of the steam-water mixture entering the steam-water separator assembly 2 will fluctuate significantly. The device uses the blades outside the cyclone guide 55 that can be dynamically adjusted in angle to accurately guide the steam-water mixture, and combines with the control action of the built-in power lead in the sliding surface through shaft 56, to dynamically adjust the blade inclination angle according to the real-time flow rate and pressure of the steam-water mixture, ensuring that the mixture enters the cavity with the optimal tangential velocity, and quickly forms a stable high-speed cyclone.

[0056] Although embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A steam-water separator exhaust structure based on a nuclear power plant steam generator, comprising a steam generator cylinder (1), characterized in that: The steam generator cylinder (1) is equipped with a cyclone separation module (5). The cyclone separation module (5) is composed of several lower connecting cylinders (53) and upper connecting cylinders (59). The two work together to form a multi-layered ring structure, which is adapted to the cylindrical cavity layout of the steam generator cylinder (1). When the steam-water mixture generated inside the steam generator cylinder (1) flows through the cyclone separation module (5), it will pass through the lower connecting cylinders (53) and the upper connecting cylinders (59) in sequence, and complete two continuous and functionally differentiated separation processes: First, the steam-water mixture enters the lower connecting cylinder (53) with a steeper slope. The steeper wall surface is used to quickly accelerate the swirling flow, avoid the initial swirling flow dispersion, and realize the first step of coarse separation of steam and water. Subsequently, the mixture after coarse separation enters the upper connecting cylinder (59) with a gentler slope. The smooth wall extends the swirling path, ensuring the continuity of the centrifugal separation effect and reducing the steam velocity, thereby reducing the probability of tiny water droplets being carried out. A fixing ring (54) is installed inside the input end of the lower connecting cylinder (53). Several toothed protrusions are uniformly fixed to the outer wall of the fixing ring (54). The fixing ring (54) is fixedly connected to the inner wall of the lower connecting cylinder (53) through the toothed protrusions, and the connection position is formed by the gap space formed by adjacent toothed protrusions. Swirling guides (55) are fixedly connected to the inner wall of the fixing ring (54). The upper surface of the swirling guides (55) is uniformly connected to the inner wall of the fixing ring (54). A sliding through shaft (56) is fixedly connected. The sliding through shaft (56) has a hollow structure and an internal power-conducting wire to control the working state of the vortex guide (55). The electrical signal transmitted through the wire drives the external blades to achieve dynamic adjustment of the tilt angle. The sliding through shaft (56) is divided into upper and lower sections along the axial direction. The lower section is fully fitted into the lower connecting cylinder (53), and the upper section is fully fitted into the upper connecting cylinder (59). The diameter of the upper section of the sliding through shaft (56) is larger than that of the lower section, and the dividing position between the upper and lower sections is precisely aligned with the slope transition dividing point of the lower connecting cylinder (53) and the upper connecting cylinder (59). The inner wall of the lower connecting cylinder (53) has a spiral opening. The lower guide channel (57) has a spiral lower reinforcing rib (58) fixedly connected to its inner side at the lower edge position corresponding to the lower guide channel (57). The inner wall of the corresponding upper connecting cylinder (59) is simultaneously provided with a spiral upper guide channel (510), and a spiral upper reinforcing rib (511) is fixedly connected to its inner side at the lower edge position corresponding to the upper guide channel (510). The distribution density of the lower guide channel (57) and the lower reinforcing rib (58) is higher than that of the upper guide channel (510) and the upper reinforcing rib (511). The spiral direction of the four is consistent with the fluid swirling direction of the steam-water mixture during the separation process, and the separated hydrophobic water is guided downward along the spiral path by directional guidance.

2. The steam exhaust structure of a steam-water separator based on a nuclear power steam generator according to claim 1, characterized in that: Both the lower connecting cylinder (53) and the upper connecting cylinder (59) adopt a funnel-shaped structure design that is wider at the top and narrower at the bottom. The upper surface area of ​​the lower connecting cylinder (53) is equal to the lower surface area of ​​the upper connecting cylinder (59). The two are assembled in a segmented integral molding manner. The slope of the lower connecting cylinder (53) is greater than that of the upper connecting cylinder (59). The separation efficiency is improved through the synergistic effect of different steep slopes.

3. The steam exhaust structure of a steam-water separator based on a nuclear power plant steam generator according to claim 1, characterized in that: The cyclone separation module (5) also includes a support chassis component (51), which is assembled inside the steam generator cylinder (1) and is integrated with a multi-layered ring structure formed by several lower connecting cylinders (53) and upper connecting cylinders (59). Furthermore, the lower surface of the support chassis component (51) is uniformly fixedly connected with an isolation side layer (52).

4. The steam exhaust structure of a steam-water separator based on a nuclear power steam generator according to claim 3, characterized in that: In the multi-layered surrounding structure formed by the lower connecting cylinder (53) and the upper connecting cylinder (59), the isolation side layer (52) is located between two adjacent layers, and the outer wall of the isolation side layer (52) is symmetrically chamfered.

5. The steam exhaust structure of a steam-water separator based on a nuclear power plant steam generator according to claim 1, characterized in that: The steam generator cylinder (1) is equipped with a steam-water separator assembly (2). The steam-water separator assembly (2) includes a steam collection chamber module (3) and a corrugated plate separation module (4). The steam collection chamber module (3), the corrugated plate separation module (4) and the cyclone separation module (5) are arranged vertically and located on the same axis. The steam-water mixture passes through the cyclone separation module (5) and the corrugated plate separation module (4) in sequence. The separated dry steam will be uniformly merged into the steam collection chamber module (3), thereby stabilizing the steam flow field. At the same time, the steam is allowed to stay in the chamber for a short time to further remove residual tiny water droplets.

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