TW201349248A - Pressurizer baffle plate and pressurized water reactor (PWR) employing same - Google Patents

Abstract

A pressurized water reactor (PWR) includes a pressure vessel and a nuclear reactor core disposed in the pressure vessel. A baffle plate is disposed in the pressure vessel and separates the pressure vessel into an internal pressurizer volume disposed above the baffle plate and an operational PWR volume disposed below the baffle plate. The baffle plate comprises first and second spaced apart plates, and includes a pressure transfer passage having a lower end in fluid communication with the operational PWR volume and an upper end in fluid communication with the internal pressurizer volume at a level below an operational pressurizer liquid level range. A vent pipe has a lower end in fluid communication with the operational PWR volume and an upper end in fluid communication with the internal pressurizer volume at a level above the operational pressurizer liquid level range.

Description

Pressurizer baffle and pressurized water reactor using the pressurizer baffle

The following are related to the nuclear reactor technology, power generation technology, nuclear reactor control technology, nuclear power generation control technology, thermal management technology, and related technologies.

The nuclear reactor employs a reactor core comprising a large number of easily splittable materials, such as materials containing uranium oxide (UO ₂ ) enriched in the easily splittable ²³⁵ U isotope. A primary coolant, such as light or heavy water, flows through the reactor core to draw heat for heating water or another secondary coolant to produce steam, or for another useful purpose. Used for power generation, which is used to drive a generator turbine. In a thermonuclear reactor, the water also functions as a neutron moderator that heats the neutrons, which enhances the reactivity of the easily splittable material. Various reactivity control mechanisms, such as mechanically operated control rods, chemical treatments with primary coolants that dissolve neutron poisons, and the like, are employed to adjust the degree of reactivity and heat of synthesis.

In a pressurized water reactor (PWR), the light water (or the primary coolant) is maintained in a sealed pressure vessel in a supercooled state, the pressure vessel also containing the reactor core. In the PWR, both the pressure and temperature of the primary coolant are controlled. An external pressurizer can be used for pressure control; however, the external pressurizer requires an additional large diameter pressure vessel to penetrate to connect the external pressurizer to the pressure vessel. Various internal pressurizer architectures are also known.

Those skilled in the art will be able to devise various modifications, which will become apparent to those skilled in the art.

In one aspect of the invention, a device includes a pressurized water reactor comprising a pressure vessel and a nuclear reactor core disposed in the pressure vessel. A baffle is disposed in the pressure vessel and divides the pressure vessel into an internal pressurizer volume disposed above the baffle and an operational PWR volume disposed below the baffle. The baffle includes a pressure transfer passage having a lower end in fluid communication with the operating PWR volume and an upper end in fluid communication with the inner pressurizer volume at a level below a level of operating pressurizer level. The vent tube has a lower end in fluid communication with the operational PWR volume and an upper end in fluid communication with the internal pressurizer volume at a level above the operating pressurizer level. In some such devices, the baffle includes first and second spaced apart panels.

In another aspect of the invention, a device includes a pressurized water reactor having a pressure vessel constructed to contain a nuclear reactor core; and a baffle disposed in the pressure vessel. The baffle divides the pressure vessel into an internal pressurizer volume disposed above the baffle and an operational PWR volume disposed below the baffle, the baffle including first and second spaced apart plates.

In another aspect of the invention, a device includes a baffle configured to be disposed in a pressurized water reactor such that a first side of the baffle faces an inner presser volume and the baffle is The opposite second side faces the operating PWR volume. a vent pipe passes through the baffle and has a first side flow with the baffle a first end of the body communication and an opposite second end in fluid communication with the second side of the baffle. The first end of the vent tube is relatively close to the baffle and the second end of the vent tube is relatively further away from the baffle.

Referring to FIG. 1, the pressurized nuclear reactor type illustrative nuclear reactor includes a pressure vessel 10 and a nuclear reactor core 12 disposed in the pressure vessel 10. The reactor core 12 includes a plurality of readily cleavable materials, such as materials containing uranium oxide (UO ₂ ) enriched in the cleavable ²³⁵ U isotope, disposed in a fuel basket or another support assembly. The fuel bundle or the like is constructed to fit into a suitable mounting bracket or clamping structure of the pressure vessel 10.

The pressure vessel contains the primary coolant up to the level L indicated in Figure 1. In the PWR architecture, the primary coolant is maintained in a supercooled state in which both pressure and temperature are controlled. In the illustrative PWR of Figure 1, the pressure is maintained using an internal pressurizer comprising a vapor bubble S disposed at the top of the pressure vessel 10. A resistive heater 14 or another heating device is provided to heat the vapor bubble to increase the pressure. In another aspect, a spray nozzle or nozzle 16 is suitably provided to inject cold water or steam into the vapor bubble to reduce the pressure. (Note that the control elements 14, 16 are shown in the drawings).

The internal pressurizer is contained within the pressure vessel 10. In this illustrative example, a baffle 20 is disposed in the pressure vessel 10. The baffle 20 divides the pressure vessel into an internal pressurizer volume 22 disposed above the baffle And operating the PWR volume 24 disposed below the baffle. The internal pressurizer volume 22 contains a portion of the primary coolant that extends from the baffle 20 up to the level L of the primary coolant in the PWR, and also contains vapor bubbles S disposed above the level L.

During normal operation of the PWR, the level of the primary coolant within the operating pressurizer level range L _op.range may vary. The operating pressurizer level range L _op.range will be understood as the allowable range of level L during any normal mode of PWR operation. Outside of the operation of the pressurizer level range L _op.range , a value for the level L constitutes an abnormal operation requiring the intervention of the reactor operator. For example, a loss of coolant accident (LOCA) can cause the primary coolant level to decrease below the operating pressurizer level range L _op.range - this is not a normal operation, and more precisely It is LOCA that generally results in a direct shutdown of the reactor operation. Similarly, some cases or conditions may cause the primary coolant level to increase again above the operating pressurizer level range L _op.range , which is not a normal operation. In some cases, the deviation of the liquid level range outside the operating pressurizer level range L _op.range may not require the reactor to be shut down, but may instead be remedied by a control operation that will operate the reactor operating parameters. Bringing into the normal range, including bringing the level L into the operating pressurizer level range L _op.range .

It will also be noted that the particular current operating conditions or modes of the PWR (eg, operating at a particular power output level or a particular primary coolant temperature) may impose a ratio of _Lop at the level of the primary coolant. _{.range is} more restrictive. As used herein, the operating pressurizer level range L _op.range will be understood as the allowable range of this level L during any normal mode of PWR operation - a particular normal mode of PWR operation may impose this primary More stringent limits on coolant levels. By way of illustration, consider the level L1 < L2 < L3 < L4 and the two modes of operation: the first mode operates at temperature T1, for which the coolant level is limited to the range [L1, L3]; and the second mode operates at Temperature T2 > T1 operation, for which the coolant level is limited to this range [L2, L4]. Assuming that it is simple, these are used in the only two modes of operation of the PWR, which operate the presser level range L _op.range [L1, L4].

With continued reference to FIG. 1, the illustrative PWR includes a central riser tube 30 disposed axially within the pressure vessel 10. The primary coolant heated by the nuclear reactor core 12 flows upwardly inside the central riser 30 and approaches the baffle 20 at the central riser 30 (or in some carefully considered embodiments) The top of the connection) is discharged. The discharged main coolant reverses the flow direction and flows downwardly outside the center riser 30 through the endless belt 32 defined by the center riser 30 and the pressure vessel 10. Optionally, the top of the central riser tube 30 includes a porous screen 34 to enhance the reverse flow from the upward direction of the inner riser tube 30 to the downward direction of the outer annulus 32.

Although not shown, in some embodiments, an integrated steam generator is disposed in the annulus 32. In a typical configuration, in either or both of the inside or outside of one or more steam generator tubes (not shown) disposed inside the annulus 32, the feed water (constituting a secondary cooling different from the primary coolant) The agent flows in a substantially upward direction. In the other of the inside or outside of the one or more steam generator tubes, the primary coolant is substantially The lower flow passes through the annulus 32. (In other words, the primary coolant may flow substantially downwardly on the outside of the steam generator tube or tubes, and the secondary coolant flows substantially upwardly inside the steam generator tube or tubes, or another In an alternative, the primary coolant can flow substantially down the inside of the steam generator tube or tubes, and the secondary coolant flows generally upwardly outside of the steam generator tubes or tubes. The steam generator tube can have various geometries, such as an upright flat steam generator tube, or a spiral steam generator tube surrounding the center riser tube 30, and the like. PWRs that include an integrated steam generator are sometimes referred to in this technology as integral PWRs. Although the integrated steam generator is typically tethered in the annulus 32, it is also contemplated to position the integrated steam generator (or a portion thereof) elsewhere inside the pressure vessel 10, such as inside the central riser 30. .

In other embodiments, the steam generator is external to the pressure vessel 10, and the primary coolant heated by the reactor core 12 is piped from the pressure vessel 10 to the external steam via a suitable conduit. Motor (not shown). In still other contemplated embodiments, the PWR is used for the purpose of generating steam, and there is no steam generator at all.

A reactivity control mechanism is suitably provided to control the degree of nuclear reactivity in the reactor core 12. In the illustrative embodiment, a plurality of neutron absorption control rods 40 are operated by a control rod drive mechanism (CRDM) or mechanism 42 to controllably insert the control rod 40 into the reactor core 12 or Control rod 40 is retracted from the reactor core 12. Inserting the control rod reduces the degree of reactivity, while retracting the control rod increases the degree of reactivity. Descriptive The CRDM 42 is an internal CRDM 42, which is disposed inside the pressure vessel 10; alternatively, the CRDM can be an external CRDM disposed outside the pressure vessel 10 and above the pressure vessel 10, and has suitable Mechanical penetrations to connect with the control rods. Additionally or alternatively, a soluble neutron poison such as boric acid can be selectively added to the primary coolant under control to control the degree of reactivity. As yet another illustrative example, the process of forming voids in the primary coolant can affect the degree of reactivity by modifying the moderator action of the primary coolant (these embodiments employ light water, heavy water, or as a neutron mitigation). Another major coolant for the agent, and suitable control of this process can provide another option or additional reactivity control mechanism.

The PWR suitably includes other components not illustrated in FIG. 1, such as monitoring sensors, configuration of valves, and other components for the safety system, external containment structures, and the like. The circulation of the primary coolant within the pressure vessel 10 (e.g., upward flow through the central riser 30 and down through the annulus 32 back to the reactor core 12) may be driven by natural convection, It may be driven actively or assisted by a primary coolant pump (not shown). The illustrative PWR pressure vessel 10 is mounted in a substantially upright position via a support skirt 44 such that the lower portion of the pressure vessel 10 containing the reactor core 12 is disposed underground. (In some carefully considered embodiments, the entire pressure vessel 10 can be under the ground such that the lower portion of the pressure vessel 10 containing the reactor core 12 is disposed in a deeper recess or pocket). Although the aforementioned partial or entire underground configuration is advantageous from a safety standpoint, other configurations are also carefully considered. If the PWR is configured at sea or on a ship to provide nuclear power for operating the ship. Again, the PWR illustrated in Figure 1 is an example, and other architectures for the reactor vessel, primary coolant circulation path, and the like can be employed.

In a PWR comprising an integrated pressurizer such as shown by the illustrative example in FIG. 1, both the inner pressurizer volume 22 and the operational PWR volume 24 are contained in the pressure vessel 10, but The baffles 20 are separated. There should be sufficient fluid communication across the baffle 20 such that the pressure variation in the internal pressurizer volume 22 is effective to control the pressure in the operational PWR volume 24. Additionally, the baffle 20 causes the upward flow of primary coolant discharged from the central riser 30 to divert into the outer annulus 32.

It is here also recognized that the thermal characteristics of the baffle 20 are also advantageously considered. To provide an illustrative example, in an operational mode similar to the PWR shown in Figure 1, the operational PWR volume is designed to operate with primary coolant included in the water in the compressed or supercooled liquid phase. . Typical values for the supercooled liquid phase range from about 310 °C to about 325 °C. To maintain the desired pressure, the internal pressurizer volume 22 is maintained at a relatively high temperature, preferably at a temperature corresponding to the saturation temperature of the primary coolant water, and preferably above the temperature of the subcooled liquid. From about 5 ° C to about 35 ° C. The water in the pressurizer volume 22 is below the water level L in the liquid phase and above the water level L in the gas phase in the vapor bubble S. Substantial fluid communication between the two volumes 22, 24, the pressure generated in the higher temperature pressurizer volume 22 is efficiently transferred to the operational PWR volume 24 to provide pressure control system.

However, it is hereby recognized that the aforementioned substantial fluid communication also implies substantial thermal communication between the two volumes 22, 24. The heat system is thus efficiently transferred from the higher temperature pressurizer volume 22 to the lower temperature, and the larger, operating PWR volume 24. Thus, the heater 14 is operated to maintain a higher temperature of the pressurizer volume to maintain the desired pressure. In the simulation, about 80 kW of power is input to the heater 14 to maintain the desired temperature of the pressurizer volume. It is here recognized that this results in an inefficient operation of the PWR and may have other deleterious effects, such as temperature gradients introduced into the operational PWR volume 24.

Accordingly, the disclosed baffles are designed to be thermally insulated. To this end, the baffle 20 is designed to inhibit the flow of the primary coolant between the two volumes 22, 24 during steady state operation. This requires an increase in the flow resistance across the baffle 20. In this illustrative example, fluid communication across the baffle 20 during normal operation is via more than one of the indicated pressure transfer passages 50. Each pressure transfer passage 50 has a lower end in fluid communication with the operating PWR volume 24 and an upper end in fluid communication with the inner pressurizer volume 22 at a level below the operating pressurizer level range L _op.range . This ensures that the upper end of the pressure transfer passage 50 remains immersed in the liquid primary coolant during any normal operation of the PWR.

The relatively high flow resistance of the baffle 20 does reduce transient performance. However, the PWRs used therein for cognitive power generation or another useful application typically operate in a steady state, allowing the most small transients to be applied, except during start and stop periods. By suppressing the two volumes The flow of the main coolant between 22 and 24, the convective heat transfer between the two volumes 22, 24 is reduced, which increases the insulation provided by the baffle 20.

The illustrative baffle 20 is also made more thermally insulated by forming the baffle 20 to include an insulating gap. In the embodiment of Figure 1, the baffle 20 includes first and second spaced apart panels 60, 62 that are separated by a gap 64 that acts as a thermal insulator. Although the two spaced apart panels 60, 62 are illustrated, the number of such spaced apart panels can be increased to three or more panels to provide further insulation clearance. The panels 60, 62 are suitably metal sheets, such as steel or another metal commensurate with the harsh environment inside the pressure vessel 10 of the PWR.

The relatively high flow resistance provided by the pressure transfer passage 50 advantageously increases the effective insulation provided by the baffle 20. However, in some unexpected situations where the pressure increases inside the pressure vessel 10, this high flow impedance can be problematic. In the event of an accident involving an increase in pressure, the increased pressure is conventionally released via a suitable release valve 52 that is suitably operatively coupled to the vapor bubble S adjacent the top of the pressure vessel 10. In this case, the high flow resistance of the baffle 20 can cause delayed release and/or rupture of the baffle 20.

In the embodiment of FIG. 1, more than one vent tube 70 is provided to adjust for an unexpected increase in pressure in the pressure vessel 10. The vent tube 70 provides a larger fluid path for relieving pressure. However, it is not desirable for the vent tube 70 to direct fluid (and thus enhance convective heat transfer) during normal operation of the PWR. In the embodiment of FIG. 1, but above the level of the operating pressurizer level _Lop.range , each vent tube 70 has a lower end in fluid communication with the operating PWR volume 24, and is internally pressurized The upper end of the fluid volume 22 is in fluid communication. This places the upper end of the vent pipe 70 in the vapor bubble S. As a result, during normal operation of the PWR, primary coolant does not flow through the vent tube 70, and as such the vent tube 70 does not provide (or provide a negligible) contribution to heat transfer across the baffle 20. In another aspect, if there is an accident in which the pressure inside the pressure vessel 10 rises, the vent tube 70 can be used to direct fluid (either liquid or gaseous primary coolant) into the internal pressurizer volume 22 for Released by the release valve 52.

Referring to Figure 2, an enlarged view (as compared to the view of Figure 1) shows a different embodiment that also includes a baffle 20 defining the inner presser volume 22 and the operational PWR volume 24 such that the vapor bubble S Positioned in the pressurizer volume 22. The internal pressurizer of Figure 2 also includes a heater 14 and a steam orifice spray nozzle or nozzle 16 for pressure control. The illustrative baffle 20 of FIG. 2 also includes first and second plates 60, 62 separated by the gap 64 and includes a pressure transfer passage 50 through the baffle 20 (only one of which passes through FIG. 2 An illustrative example is shown, and further includes a vent tube 70 (again, only one of them is shown by the illustrative example in FIG. 2). As seen in Figure 2, the lower end 82 of the vent tube 70 is in fluid communication with the operational PWR volume 24, and the upper end 84 of the vent tube 70 extends over the operating presser level range L _op.range into the Steam bubble S. In FIG. 2, the snorkel support 86 provides support for the upper end 84 of the vent tube 70, which extends further away from the baffle 20 as compared to the lower end of the vent tube 70.

In the detailed shape in which the pressure vessel 10 defines a portion of the internal pressurizer volume 22, and in the use of a different porous screen 34' at the upper end of the central riser 30, the embodiment of FIG. 2 and the embodiment of FIG. different. The illustrative porous screen 34' extends from the central riser 30 to the baffle 20 such that all of the upwardly flowing primary coolant exiting the upper end of the central riser 30 passes through the porous screen 34'. It should be noted that in some embodiments, the porous screen 34' is integrally formed with the central riser 30, such as by forming an opening (i.e., perforation) at the top of the central riser 30 to define the Porous screen 34'.

In the embodiment of Figures 1 and 2, the pressure transfer passage 50 is located outside of the porous screen 34, 34'. In this outer position, the primary coolant flow is transitioning from the upward flow direction to the downward flow direction, and accordingly has a substantiality that is directed parallel to the baffle 20 (or, in a suitable flow design, completely Ground) lateral flow component. This lateral flow system traverses the flow direction inside the pressure transfer passage 50, which further reduces the flow of the primary coolant between the equal volumes 22, 24.

Referring to Figure 3, the pressure transfer passage 50 is suitably constructed to further reduce the flow of the primary coolant between the equal volumes 22, 24. In the illustrative pressure transfer passage 50 of FIG. 3, this is by adjusting the passage of the baffle 20 (i.e., the first and second constituent plates 60, 62 in this embodiment). The pressure transfer passage 50 of the pressure tube 90 is completed. At a level below the operating pressurizer level range _Lop.range , the regulator tube 90 has a lower end 92 in fluid communication with the operating PWR volume 24 and an upper end in fluid communication with the internal pressurizer volume 22. 94 (shown in Figures 1 and 2). The lower end 92 of the pressure regulating tube 90 includes a closure plate 100 and is in fluid communication with the operational PWR volume 24 via a perforation or hole 102 in the side of the lower end 92. Further reduction in the primary coolant flow is provided by the external coaxial tube 104. Since the primary coolant flow adjacent the lower end 92 in the operational PWR volume 24 is substantially lateral (again, the upward flow from the inner side of the central riser 30 transitions to the downward flow in the outer annulus 32) The outer coaxial tube 104 promotes the formation of a primary coolant stagnation zone at the lower end 92.

The illustrative architecture including components 100, 102, 104 is merely an illustrative example of the architecture of the pressure transfer passage 50 to reduce the flow of primary coolant between the equal volumes 22, 24. Various other configurations of baffles, neckings, flow barriers, and the like can also be carefully considered to provide a reduced flow of the primary coolant between the volumes 22, 24. Any such configuration or architecture will provide sufficient fluid communication to enable the pressure delivery channel to perform its primary function, while the pressure in the operational PWR volume 24 can be controlled by adjusting the pressure in the internal pressurizer volume 22. . The range of fluid communication sufficient for this purpose will depend on the expected normal operating pressure, the acceptable (i.e., designed) transient spacing, the type of primary coolant, and the like.

Referring to Figures 4 and 5, various ways can be utilized to provide thermal insulation by the structure of the baffle 20 including the first and second panels 60, 62 by which the first and second panels are 64 separated. In Figure 4, the two plates 60, 62 are separated by the gap 64, but are not sealed at their periphery. A suitable strut 110 locks the panels 60, 62 together and defines the gap 64. In the embodiment of Figure 4, the gap 64 is not a sealed one. volume of. Conversely, the first and second spaced apart panels 60, 62 define an unsealed volume 64 that is filled with water when the baffle 20 is immersed in water. Insulation is provided because the water in the unsealed volume 64 (or another primary coolant) is stagnant and does not flow (or at least does not flow rapidly). As such, the primary coolant in the unsealed volume 64 transfers heat primarily by heat conduction, but not by heat convection.

Embodiments such as Figure 5 can be used if further insulation is desired. In another alternative embodiment, the baffle 20' includes two plates 60, 62 separated by the gap 64, wherein the plates 60, 62 are surrounded by a metal or an environment opposite the PWR Sealed by an annular seal 112 of another durable material. As a result, in the embodiment of Figure 5, the gap 64 is a sealed volume. The sealed volume can be filled with a gas 114 such as air, nitrogen, or the like. This method ensures that the heat is only transported across the gap 64 by thermal conduction. In another variation, the volume of the seal that will be an empty volume (i.e., "containing" a vacuum) is carefully considered.

The illustrative baffles 20, 20' provide substantial insulation. However, other insulating baffles have also been carefully considered. For example, another carefully considered baffle includes a single panel (and thus no gap) such that the single panel includes a durable insulating material in the environment inside the pressure vessel 10 of the PWR.

The steady state simulation of the baffle 20 of Figure 4 in the pressurizer architecture of Figure 2 has been performed such that the pressure transfer passage is embodied as shown in Figure 3 and additionally includes the vent tube 70. These simulations use the operating conditions of the supercooled primary coolant in the operating PWR volume 24, and the internal pressurizer volume 22 contains There is a primary coolant water at a higher temperature which is about 11 ° C higher than the subcooling temperature corresponding to the saturation temperature of the primary coolant water. The two volumes 22, 24 are separated using a single steel plate having high flow conductivity indicating that the power of about 80 kW to the heater 14 is sufficient to maintain the pressurizer at the saturation temperature. In contrast, when the disclosed baffle 20 is used, this heating is reduced to a few kW. This steady state simulation indicates that most of the improved performance is due to the restricted flow of the primary coolant across the baffle 20 in the steady state, and the use of the spaced plates 60, 62 provides a secondary heat improvement.

The vent tube 70 operates effectively in certain unexpected situations. For example, in the case of a loss of coolant accident (LOCA) where there is a complete cut-off at the pressure relief valve nozzle 52, the vent tube 70 minimizes the pressure acting on the baffle 20. The vent tube 70 allows pressurized water (or another pressurized primary coolant) in the operating PWR volume 24 to bypass the pressure transfer passage 50 such that the pressure differential across the baffle 20 is minimized. The vent support 86 allows for uneven expansion between the vent tube 70 and the housing of the pressure vessel 10.

Referring to Figures 6-8, the baffle 20 can be mounted in the pressure vessel 10 in a variety of connection configurations. Referring to Figure 6, an embodiment for supporting the baffle 20 employs a lower support ring 120 that is welded to the housing 122 of the pressure vessel 10 and has an upper support ring 124 that is also welded to the housing 122. It limits the baffle 20 from any differential pressure across the baffle 20, as in the case of the LOCA accident, where the pressure relief valve nozzle 52 has a complete cut rupture. In the connection structure of Figure 6, via the housing The flow of the outer periphery of the 122 connection across the baffle 20 can be completely suppressed or blocked by the inclusion of a wedge 126 disposed on the upper metal plate member 60 of the baffle 20 and the housing 122 or the support thereon. Between the rings 124. The wedge 126 allows for uneven expansion between the baffle 20 and the housing 122 while maintaining a fluid tight seal.

Referring to Figures 7 and 8, another alternative embodiment includes attaching the lower plate member 62 of the baffle 20 to the housing 122 of the pressure vessel 10 by welding. In this configuration, the upper plate member 60 is supported on the lower plate member 62 by the support post 110. Any potential displacement of the housing 122 due to pressure expansion and temperature expansion is suitably adjusted by the intermediate components disposed between the housing 122 and the lower plate member 62 to absorb the uneven expansion. In the embodiment of FIG. 7, the interposer includes a tab 130 formed by removing a portion of the housing 122 by an etching or mechanical polishing process or the like. In the embodiment of FIG. 8, the intermediate component includes an intermediate carrier 132 that is welded to the housing 122.

The connection architecture described with reference to Figures 6-8 is an illustrative example, and other connection architectures that accommodate uneven thermal expansion and housing displacement while maintaining a suitable fluid seal are also considered.

The preferred embodiment has been illustrated and described. Obviously, modifications and variations will occur to others upon reading and understanding the foregoing detailed description. The present invention is intended to be construed as including all such modifications and variations as may fall within the scope of the appended claims.

10‧‧‧ Pressure vessel

12‧‧‧ core

14‧‧‧heater

16‧‧‧ nozzle

20‧‧ ‧Baffle

20’‧‧‧Baffle

22‧‧‧ Pressurizer volume

24‧‧‧Water pressure reactor volume

30‧‧‧Center riser

32‧‧‧环带带

34‧‧‧ screen

34’‧‧‧ Screen

40‧‧‧Control rod

42‧‧‧Control rod drive mechanism

44‧‧‧Support skirt

50‧‧‧pressure transmission channel

52‧‧‧ release valve

60‧‧‧ boards

62‧‧‧ boards

64‧‧‧ gap

70‧‧‧ snorkel

82‧‧‧Bottom

84‧‧‧Upper

86‧‧‧Support

90‧‧‧Tuning tube

92‧‧‧Bottom

94‧‧‧Upper

100‧‧‧Close the board

102‧‧‧ hole

104‧‧‧With axial tube

110‧‧‧ pillar

112‧‧‧Ring seals

114‧‧‧ gas

120‧‧‧ lower support ring

122‧‧‧ housing

124‧‧‧Upper support ring

126‧‧‧ wedges

130‧‧‧ tongue

132‧‧‧ bracket

The present invention can take the form of configurations of various components and components, and configurations in various process and process operations. This drawing is for illustrative purposes only and is not to be construed as limiting the invention.

Figure 1 graphically shows a pressurized water reactor containing an internal pressurizer.

2 graphically shows the upper portion of the PWR of the other embodiment of FIG. 1 having the internal pressurizer and selected associated components.

Figure 3 graphically shows an illustrative embodiment in which the pressure transfer passage is embodied by a pressure regulating tube.

Figures 4 and 5 graphically illustrate two illustrative thermal barrier embodiments.

Figures 6-8 graphically show a suitable configuration for mounting the baffle in the pressure vessel.

10‧‧‧ Pressure vessel

14‧‧‧heater

16‧‧‧ nozzle

20‧‧ ‧Baffle

22‧‧‧ Pressurizer volume

24‧‧‧Water pressure reactor volume

30‧‧‧Center riser

32‧‧‧环带带

34’‧‧‧ Screen

50‧‧‧pressure transmission channel

52‧‧‧ release valve

60‧‧‧ boards

62‧‧‧ boards

64‧‧‧ gap

70‧‧‧ snorkel

82‧‧‧Bottom

84‧‧‧Upper

86‧‧‧Support

Claims (29)

A device comprising: a pressurized water reactor comprising: a pressure vessel, a nuclear reactor core disposed in the pressure vessel, a baffle disposed in the pressure vessel, and dividing the pressure vessel into the baffle An internal pressurizer volume, and an operational PWR volume disposed below the baffle, wherein the baffle includes a pressure transfer passage, the pressure transfer passage having a position below a level of the operating pressurizer level a lower end of the PWR volume fluid communication and an upper end in fluid communication with the internal pressurizer volume, and a vent tube having a lower end in fluid communication with the operational PWR volume at a level above the operating pressurizer level An upper end in fluid communication with the internal pressurizer volume. The device of claim 1, wherein the vent tube traverses and passes through the baffle. The apparatus of claim 1, wherein the pressure transmission passage comprises at least one pressure regulating tube, the pressure regulating tube passes through the baffle plate, and has a level lower than a level of the operating pressurizer liquid level The operating PWR is in fluid communication with a lower end and an upper end in fluid communication with the internal pressurizer volume. The apparatus of claim 1, wherein the fluid flow path in the pressure transfer passage traverses and passes through the baffle. The device of claim 1, wherein the baffle comprises first and second spaced apart panels. The apparatus of claim 5, wherein the first and second partitioning members define an unsealed volume filled with water when the baffle is immersed in water. The device of claim 1, wherein the baffle comprises first and second spaced apart panels defining a sealed volume. The device of claim 1, wherein the baffle comprises: first and second spaced apart plates defining a sealed volume; and a gas disposed in the sealed volume. The device of claim 1, wherein the baffle comprises a thermal barrier between an internal pressurizer volume disposed above the baffle and an operational PWR volume disposed below the baffle. The apparatus of claim 1, wherein the PWR further comprises: a central riser disposed in the pressure vessel and having a lower end configured to receive an upwardly flowing primary coolant from the nuclear reactor core, and a configuration The main coolant flowing upward is discharged toward the upper end of the baffle. The apparatus of claim 10, wherein the PWR further comprises: a porous screen surrounding the upper end of the central riser. The apparatus of claim 11, wherein the porous screen extends from the central riser to the baffle such that all of the upward flowing primary coolant discharged at the upper end of the central riser passes through the porous screen . Such as the device of claim 11, wherein the pressure transmission The lower end of the passage is disposed outside the porous screen. A device comprising: a pressurized water reactor comprising: a pressure vessel constructed to contain a nuclear reactor core, and a baffle disposed in the pressure vessel, and dividing the pressure vessel into an interior disposed above the baffle The press volume, and the operating PWR volume disposed below the baffle, the baffle includes first and second spaced apart plates. The apparatus of claim 14, wherein the first and second partitioning members define an unsealed volume filled with water when the baffle is immersed in water. The device of claim 14, wherein the baffle comprises first and second spaced apart panels defining a sealed volume. The device of claim 16, wherein the baffle further comprises: a gas disposed in the sealed volume. The device of claim 14, wherein the baffle comprises a thermal barrier between an internal pressurizer volume disposed above the baffle and an operational PWR volume disposed below the baffle. The device of claim 14, wherein the PWR further comprises: a vent tube having a lower end in fluid communication with the operational PWR volume and a pressure with the internal pressure at a level above the operating pressurizer level The upper end of the volume of fluid communication. The device of claim 19, wherein the baffle comprises The pressure transfer passage, at a level below the operating pressurizer level, has a lower end in fluid communication with the operating PWR volume and an upper end in fluid communication with the internal pressurizer volume. The device of claim 14, wherein the baffle comprises a pressure transfer passage having a lower end in fluid communication with the operational PWR volume and an upper end in fluid communication with the inner pressurizer volume. The device of claim 21, wherein the pressure transmission passage comprises at least one pressure regulating tube that passes through the baffle. A device comprising: a baffle configured to be disposed in a pressurized water reactor such that a first side of the baffle faces an inner presser volume and an opposite second side of the baffle faces a PWR volume; and a vent tube passing through the baffle and having a first end in fluid communication with the first side of the baffle and an opposite second end in fluid communication with the second side of the baffle; The first end of the vent tube is relatively close to the baffle and the second end of the vent tube is relatively further away from the baffle. The device of claim 23, wherein the distance from the second end of the vent pipe to the baffle is such that the second end of the vent pipe is positioned above a level of the operating pressurizer level Effective. The device of claim 23, wherein the baffle comprises first and second partitioning plates, the first and second partitioning plates defining a water-filled material when the baffle is immersed in water Unsealed volume. The device of claim 23, wherein the baffle comprises A first and a second partitioning member defining a sealed volume. The device of claim 23, wherein the baffle comprises: first and second spaced apart plates defining a sealed volume; and a gas disposed in the sealed volume. The device of claim 23, wherein: the baffle includes a pressure transfer passage different from the vent tube, the pressure transfer passage passing through the baffle and having fluid communication with the first side of the baffle The first end and the opposite second end in fluid communication with the second side of the baffle, and the second end of the pressure transfer passage is relatively closer to the baffle than the second end of the vent tube. The device of claim 28, wherein the distance from the second end of the vent pipe to the baffle is such that the second end of the vent pipe is positioned above a level of the operating pressurizer level Effectively, and the distance of the second end of the pressure transfer passage from the baffle is effective to position the second end of the pressure transfer passage at a level below the level of the operating pressurizer level.