CN1238859C - Fuel aggregate - Google Patents

Abstract

A boiling water reactor (BWR) fuel element includes a swirling device, which forms spiral paths for imparting vortical flow to the upwards flowing coolant, and a debris collection system. A BWR fuel element includes (a) an axial swirling device which is arranged in the bottom of the bottom closure plate and which has vanes positioned around a central hub for imparting an upwards vortical flow to the upwardly flowing coolant; (b) a vertical open-ended cylindrical body which extends upwards in the bottom closure plate to a predetermined point at the downstream side of the swirling device and through which the vortex of debris-laden coolant flows upwardly; and (c) a debris collection section which is located between the outer surface of the bottom of the cylindrical element and the inner surface of the bottom closure plate and which collects sunken debris after it has passed outwards from the top of the cylindrical body.

Description

Fuel aggregate

Technical field

The present invention relates to install to fuel aggregate in the boiling water type atomic reactor as raw material, the particularly the sort of snotter that can prevent to sneak in cooling medium flows into its inner fuel aggregate.

Background technology

Shown in Figure 55, install to fuel aggregate in the boiling water type atomic reactor as raw material and be and many fuel rods 2 and at least 1 water bar 3 are contained in the tubular trough of belt box 1 and constitute.Adorning top tie-plate 4 and bottom tie-plate 5 respectively in the upper and lower end parts of this fuel aggregate, the upper and lower end parts of fuel rod 2 and water bar 3 is separately fixed on top tie-plate 4 and the bottom tie-plate 5 by the bottom end plug 7 of upper end plugs 6.And on water bar 3 vertically sky open certain intervals ground a plurality of liners 8 be installed, by these liners 8 fuel rod 2 is supported to permutation, and suppresses the bending of fuel rod 2.

Figure 56 is that ( イ プ レ-ト) 5 bottom end plug supports the planimetric map with an example of Network Dept. 9 to expression bottom tie-plate.Mobile and the limbers 11 passed through of the rising that this Network Dept. 9 is provided with the tube portion 10 that the bottom end plug 7 of supporting fuel rod 2 and water bar 3 inserts of being used for, cooling medium is formed makes progress from the below.

Figure 57 is inserted into the skiagraph that the insertion state of 9 li of Network Dept.s is represented enlargedly with bottom end plug 10.Shown in the arrow among Figure 57, cooling medium a flows into from the fuel aggregate bottom, after the limbers 11 by bottom tie-plate 5, on one side the heat of fuel rod 2 generations is removed, on one side to the diffluence of fuel aggregate top.

Yet in the reactor prophylactic repair, though be the lid of reaction pressure vessel is opened and to be carried out the exchange of fuel aggregate, in this prophylactic repair process, the sheet metals such as iron wire that use in the time of might be with operation are fallen in the reactor pressure vessel.Also may reactor member peel off because of oxidation or other reasons form the part, this stripping film drops in the reactor pressure vessel.

Because snotteres such as these sheet metals or stripping film all are that weight is less usually, thereby can flow in the reactor process process in the fuel aggregate, might produce be hooked in the fuel aggregate etc. improper.Therefore, once develop in the past a kind of snotter that stops and flow into technology (for example the Japanese patent gazette spy opens flat 7-151882 number) in the fuel aggregate.

Figure 58 is the structure of expression by the snotter trap setting of this prior art formation.This snotter trap setting is to be provided with in the cooling medium inflow portion that oral area is opened in the lower end central authorities of bottom tie-plate 5 to reverse plate 13, and periphery is provided with the ring 14 that cooling medium a is guided of tubular above it, is provided with above this ring and picks up filtrator 15.Therefore, the snotter that flow into 5 li of bottom tie-plates together along with cooling medium a is flowed add the rotation composition by reversing plate 13, the snotter that density is higher than cooling medium a is split into the outside that is arranged on the ring 14 that reverses plate 13 downstreams.

Because in the above-mentioned existing snotter trap setting, by reverse revolving force that plate forms a little less than, may not necessarily fully separate snotter with cooling medium a problem such as the pressure loss is bigger in addition sometimes.

Summary of the invention

The present invention makes for the problem that solves above-mentioned prior art existence, its objective is that providing a kind of can fully improve the snotter capturing efficiency, can reduce the pressure loss again, can stop snotter along with cooling medium flow in the fuel aggregate together really, can keep the fuel aggregate of viability effectively.

In order to achieve the above object, the present invention takes following technical scheme:

Described fuel aggregate, it is loaded on the pile core portion of the reactor pressure vessel of boiling water type atomic reactor, and it has: many fuel rods; Support the top tie-plate and the bottom tie-plate of the upper and lower side of these fuel rods; The compartment of terrain is configured between above-mentioned two tie-plates, a plurality of liners at the above-mentioned fuel rod of maintenance interval each other; And the trough of belt box of all outer circumferential sides of above-mentioned these members of coating; The cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flows and be passed to above-mentioned fuel rod side, it is characterized in that:

Be provided with helical blade and vertical cylinder; Above-mentioned helical blade is the lower central position that is configured in above-mentioned bottom tie-plate, has center hub and a plurality of blade that the cooling medium that will rise forms rotational flow; Above-mentioned cylinder is the upper and lower side opening that rises to certain altitude in the downstream of helical blade; In addition, in the outer lower portion of above-mentioned cylinder, at the inner surface side formation snotter recoverer of above-mentioned bottom tie-plate, it is to make the snotter in above-mentioned cooling medium flows into above-mentioned bottom tie-plate fall and be reclaimed,

In the arranged outside outside of the cylinder in helical blade downstream out cylinder, form dual cylindric, and with the space obturation in the downstream of above-mentioned inside cylindrical body and outside cylindrical, and on the perisporium of above-mentioned inside cylindrical body, offer a plurality of spiral fashions or skewed slit or circular hole, and make can be recovered to the snotter that flows out from the slit of this cylinder or circular hole and outside cylindrical between the gap in.

Aggregate is produced in described combustion, it is characterized in that: uprightly the vertical cylinder body to the upper and lower side opening of certain altitude is the cylinder of eyed structure in the downstream of helical blade.

Described fuel aggregate is characterized in that: perisporium forms the concavo-convex of section indentation on the top of the cylinder of eyed structure, makes can carry out snotter by this jog and reclaim.

Described fuel aggregate is characterized in that: outstanding setting is used for stoping the snotter of the ring-type of the snotter rising that is blended in the cooling medium to catch and uses hook portion near the inner peripheral surface the upper end of cylinder.

Described fuel aggregate is characterized in that: it is cylinder to be made have the part that becomes minor diameter to cooling medium downstream cone, the distolateral minor diameter that also has tubular thereon.

Described fuel aggregate is characterized in that: configuration a plurality of cylinders are set up and down, and the diameter of upside cylinder is made little than downside cylinder, form annular gap between each cylinder.

Described fuel aggregate is characterized in that: sky is opened certain configuration and the 2nd roughly the same cylinder of this cylinder diameter at interval in the upper and lower above cylinder, by assembly wall this 2nd cylinder is bearing on the inside surface of bottom tie-plate.

Described fuel aggregate is characterized in that: the top of cylinder is made becomes large diameter taper wide diameter portion upward gradually, and offers a plurality of fenestras at the suitable position of the bottom level with the snotter recoverer of above-mentioned cylinder perisporium; And be provided with highlightedly from the inside surface of bottom tie-plate be projected into above-mentioned cylinder the top, close on the downside minor diameter conoid protuberance in the upper end open portion of above-mentioned cylinder.

Described fuel aggregate is characterized in that: the net that snotter is caught usefulness is set on the fenestra of cylinder.

Described fuel aggregate is characterized in that: curl or skewed offer many slits near the perisporium the upper end of cylinder.

Described fuel aggregate is characterized in that: offer a plurality of circular holes near the perisporium the upper end of cylinder.

Described fuel aggregate is characterized in that: opposite guide body of catching usefulness to outstanding snotter with rotating flow is set on the slit inlet portion of being offered on the cylinder.

Described fuel aggregate is characterized in that: make the aperture that is opened in the circular hole on the cylinder different because of upstream and downstream.

Described fuel aggregate is characterized in that: the upper end connecting portion in dual cylindrical portions may downstream is made eyed structure.

Aggregate is produced in described combustion, it is characterized in that: the bottom of outside cylindrical and bottom tie-plate are broken away from, form the inside and outside ANALYSIS OF COOLANT FLOW that is communicated with this outside cylindrical body.

Described fuel aggregate is characterized in that: be provided with the interior periphery of the last ora terminalis of cylinder and crown snotter that the top surrounds fallen and use guide body.

Described fuel aggregate, it is characterized in that: fall with the inner peripheral surface of the outside tubular dip portion of guide body and the gap between the outer peripheral face of cylinder upper end by crown snotter and form the decline stream, many tongue-shaped snotter capture boards are set in this decline stream.

Described fuel aggregate is characterized in that: with the snotter capture board make forward end raise gradually the inclination that erects obliquely tabular, roughly become flatly front end to be bent into the upwards hook-type of " L " font tabular or concave upright roughly be the crooked tabular of semicircle arcuation.

Aggregate is produced in described combustion, it is characterized in that: the snotter that sets a plurality of needle-likes on the snotter recoverer is caught fin.

Aggregate is produced in described combustion, it is characterized in that: on the inner peripheral surface of bottom tie-plate, the ring-type jog is set along the vertical direction, multistage.

Described fuel aggregate is characterized in that: the jog of bottom tie-plate inner peripheral surface is made the narrower and more roomy shape in inside chase of the inlet of chase.

Described fuel aggregate is characterized in that: the crown snotter that is installed in the cylinder upper end falls with the external diameter of guide body littler than the diameter in the coolant entrance hole of tie-plate lower end, bottom.

Fuel aggregate of the present invention, it is loaded on the pile core portion of the reactor pressure vessel of boiling water type atomic reactor, and top tie-plate and bottom tie-plate, the compartment of terrain that it has many fuel rods, support the upper and lower side of these fuel rods be configured between above-mentioned two tie-plates, keep a plurality of liners at above-mentioned fuel rod interval each other, and coat the trough of belt box of all outer circumferential sides of above-mentioned these members; The cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flow and be passed to above-mentioned fuel rod side, it is characterized in that: be provided with helical blade, it is the lower central position that is configured in above-mentioned bottom tie-plate, has center hub and a plurality of blade that the cooling medium that will rise forms rotational flow; On the inside surface of above-mentioned bottom tie-plate, along being circumferentially with many opposite hook-type snotter capture boards of rotational flow one-tenth that form with above-mentioned helical blade to composition.

Described fuel aggregate is characterized in that: the hook-type snotter capture board of bottom tie-plate inside surface is an eyed structure.

Described fuel aggregate is characterized in that: replace the set charging in tie-plate lower end, bottom with guide member or make its dual-purpose ground, helical blade is set, it is given prominence in above-mentioned tie-plate lower end.

Described fuel aggregate is characterized in that: the center hub of helical blade extends to the downstream.

Fuel aggregate of the present invention, it is loaded on the pile core portion of the reactor pressure vessel of boiling water type atomic reactor, and top tie-plate and bottom tie-plate, the compartment of terrain that it has many fuel rods, support the upper and lower side of these fuel rods be configured between above-mentioned two tie-plates, keep the trough of belt box of all outer circumferential sides of these members in a plurality of liners at above-mentioned fuel rod interval each other, the coating; The cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flow and be passed to above-mentioned fuel rod side, it is characterized in that: the coolant entrance portion at above-mentioned bottom tie-plate is provided with cylinder element, and it has many spiral flow path along the vertical direction; On the centrifugal action part of the cooling medium that flows through above-mentioned each bar spiral flow path, form the concavo-convex ditch vertical with above-mentioned flow of coolant direction.

Fuel aggregate of the present invention, it is loaded on the pile core portion of the reactor pressure vessel of boiling water type atomic reactor, its have many fuel rod, the top tie-plate of upper and lower side that supports these fuel rods and bottom tie-plate, compartment of terrain be configured between above-mentioned two tie-plates, keep above-mentioned fuel rod interval each other a plurality of liners, coat the trough of belt box of all outer circumferential sides of above-mentioned these members; The cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flow and be passed to above-mentioned fuel rod side, it is characterized in that: the central lower in the tie-plate of above-mentioned bottom erects the flow limitation plate of many lengthwises, and these flow limitation plates are made the structure of bending towards periphery; On the other hand, the stream that umbrella is set at the upper end position of above-mentioned flow limitation plate closes tight plate, and making to flow the rising of cooling medium is transformed into radial flowing downwards; And have longitudinally the snotter of many chases in the inside surface setting of above-mentioned bottom tie-plate and catch portion.

Described fuel aggregate, its special sheet is: be provided with the nozzle that cooling medium is risen and flows and dwindle on the coolant flow inlet hole of tie-plate lower end, bottom.

Fuel aggregate of the present invention, it is the pile core portion that installs to reactor pressure vessel as raw material of boiling water type atomic reactor, have many fuel rods, support the top tie-plate and the bottom tie-plate of the upper and lower side of these fuel rods, the compartment of terrain is configured between above-mentioned two tie-plates, the a plurality of liners that keep above-mentioned fuel rod interval each other, coat the trough of belt box of the whole outer circumferential sides of above-mentioned these members, the cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flow and be passed to above-mentioned fuel rod side, it is characterized in that: be provided with in the inside of above-mentioned bottom tie-plate that main flow direction with respect to cooling medium tilts, the snotter of the perforate shape that the prevention snotter passes through is removed plate, and remove the upper end side lower position of plate at above-mentioned snotter, and forming the snotter recoverer in the inner surface portion of above-mentioned bottom tie-plate, its is reclaimed remove the snotter that plate falls from above-mentioned snotter.

Described fuel aggregate is characterized in that: it is the shape that the center from the bottom tie-plate erects gradually to periphery that snotter is removed plate.

Described fuel aggregate is characterized in that: it is to constitute by the fuel supporting of bottom tie-plate upper end is made from its center to the dip plane that periphery erects gradually with Network Dept.'s lower surface that snotter is removed plate.

Described fuel aggregate is characterized in that: the snotter recoverer in the tie-plate of bottom is made wing shape.

Fuel aggregate of the present invention, it is the pile core portion that installs to reactor pressure vessel as raw material of boiling water type atomic reactor, and the top tie-plate of upper and lower side and bottom tie-plate, the compartment of terrain of have many fuel rods, supporting these fuel rods be configured between above-mentioned two tie-plates, keep a plurality of liners at above-mentioned fuel rod interval each other, coat the trough of belt box of the whole outer circumferential sides of above-mentioned these members; The cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flow and be passed to above-mentioned fuel rod side, it is characterized in that: above-mentioned fuel rod the lower end is bearing in the coolant flow path that forms bending in the bottom end plug on the tie-plate of above-mentioned bottom, make the above-mentioned cooling medium back of rising form to flowing of side and circulate; Make mouthful being opened on the upside space of limbers of export department of this coolant flow path, this limbers is to be opened in the Network Dept. of above-mentioned bottom tie-plate.

Fuel aggregate of the present invention, it is the pile core portion that installs to reactor pressure vessel as raw material of boiling water type atomic reactor, and the top tie-plate of upper and lower side and bottom tie-plate, the compartment of terrain of have many fuel rods, supporting these fuel rods be configured between above-mentioned two tie-plates, keep a plurality of liners at above-mentioned fuel rod interval each other, coat the trough of belt box of the whole outer circumferential sides of above-mentioned these members; The cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flow and be passed to above-mentioned fuel rod side, it is characterized in that: the structure that does not have the limbers at bottom end plug support holes position is in addition made by the Network Dept. of bottom tie-plate, and the coolant flow path of formation bending in the end plug of above-mentioned bottom, above-mentioned cooling medium rising back is formed to flowing of Jie side circulate.

Described fuel aggregate is characterized in that: the outlet shape of the coolant flow path that forms in the end plug of bottom is looked face and is seen and be parallel wire, "＜" font, " L " font, " S " font, " T " font or crank (Network ラ Application Network) shape.

Fuel aggregate of the present invention, it is the pile core portion that installs to reactor pressure vessel as raw material of boiling water type atomic reactor, and the top tie-plate of upper and lower side and bottom tie-plate, the compartment of terrain of have many fuel rods, supporting these fuel rods be configured between above-mentioned two tie-plates, keep a plurality of liners at above-mentioned fuel rod interval each other, coat the trough of belt box of the whole outer circumferential sides of above-mentioned these members; The cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate is formed rise and flows and be passed to above-mentioned fuel rod side, it is characterized in that: in the inner space of above-mentioned bottom tie-plate alternately configuration relatively and many snotteres of the main flow direction of cooling medium inclination sneak into and prevent plate.

Described fuel aggregate is characterized in that: it is bending upward that above-mentioned snotter is sneaked into the front end that prevents plate.

Described fuel aggregate, it is characterized in that: snotter is sneaked into and is prevented that plate from being the sheet material formation by many arranged spaced that roughly are " V " font, their both ends are provided with in contact with the inside surface of bottom tie-plate respectively, and on the non-coincidence position of above-mentioned each sheet material, forming peristome, they become flow of coolant to crawl stream.

Described fuel aggregate, it is characterized in that: the cylinder inner wall face in the tie-plate of bottom, reverse on plate and helical blade surface, other each element surfaces and form rill, it is many tiny ditches along the ANALYSIS OF COOLANT FLOW direction are arranged side by side and constitute, and the resistance in the coolant flow path is reduced.

Description of drawings:

Fig. 1 is the whole sectional drawing of the fuel aggregate of expression the 1st embodiment of the present invention;

Fig. 2 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the 2nd embodiment of the present invention;

Fig. 3 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 3rd embodiment;

Fig. 4 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 4th embodiment;

Fig. 5 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 5th embodiment;

Fig. 6 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 6th embodiment;

Fig. 7 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 7th embodiment;

Fig. 8 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 8th embodiment;

Fig. 9 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 9th embodiment;

Figure 10 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 10th embodiment;

Figure 11 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 11st embodiment;

Figure 12 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 12nd embodiment;

Figure 13 is the amplification profile diagram of the interior cylinder section major part of the bottom tie-plate of expression the present invention the 13rd embodiment;

Figure 14 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 14th embodiment;

Figure 15 is the figure that the comparison of the snotter separation rate of plate and the present invention's the 14th embodiment and the pressure loss is reversed in expression;

Figure 16 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 15th embodiment;

Figure 17 is the amplification profile diagram of the interior cylinder section major part of the bottom tie-plate of expression the present invention the 16th embodiment;

Figure 18 is the figure that the comparison of the snotter separation rate of plate and the present invention's the 16th embodiment and the pressure loss is reversed in expression;

Figure 19 is the amplification profile diagram of the interior cylinder major part of the bottom tie-plate of expression the present invention the 17th embodiment;

Figure 20 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 18th embodiment;

Figure 21 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 19th embodiment;

Figure 22 is a synoptic diagram of at length representing the major part of above-mentioned the 19th embodiment;

Figure 23 is the figure that changes the shape example of expression the 20th embodiment;

Figure 24 is the figure that changes the shape example of expression the 20th embodiment;

Figure 25 is the figure that changes the shape example of expression the 20th embodiment;

Figure 26 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 21st embodiment;

Figure 27 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 22nd embodiment;

Figure 28 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 23rd embodiment;

Figure 29 is the whole sectional drawing of the fuel aggregate of expression the present invention the 24th embodiment;

Figure 30 is the figure that the comparison of the snotter separation rate of plate and the present invention's the 24th embodiment and the pressure loss is reversed in expression;

Figure 31 is the whole sectional drawing of the fuel aggregate of expression the present invention the 24th embodiment;

Figure 32 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 25th embodiment;

Figure 33 is the sectional drawing of obtaining along the A-A line of Figure 32;

Figure 34 is the amplification profile diagram of tie-plate lower end, the bottom guide body major part of expression the present invention the 26th embodiment;

Figure 35 is the sectional drawing of obtaining along the B-B line of Figure 34;

Figure 36 is the whole sectional drawing of the fuel aggregate of the present invention's the 27th embodiment;

Figure 37 is the sectional drawing of obtaining along the C-C line of Figure 36;

Figure 38 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 28th embodiment;

The (a) and (b) of Figure 39 be respectively the D of Figure 38 to view and E to view;

Figure 40 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 29th embodiment;

Figure 41 is the sectional drawing of obtaining along the F-F line of Figure 40;

Figure 42 is the sectional drawing of obtaining along the G-G line of Figure 40;

Figure 43 is the amplification oblique drawing of Figure 42;

Figure 44 is the amplification profile diagram of the fuel aggregate of the present invention's the 30th embodiment;

Figure 45 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 31st embodiment;

Figure 46 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 32nd embodiment;

Figure 47 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 33rd embodiment;

Figure 48 is the amplification profile diagram of bottom end plug major part of the fuel aggregate of expression the present invention the 34th embodiment;

Figure 49 is the amplification profile diagram of bottom end plug major part shape of the fuel aggregate of expression the present invention the 35th embodiment;

Figure 50 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 36th embodiment;

Figure 51 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 37th embodiment;

Figure 52 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 38th embodiment;

Figure 53 is the amplification profile diagram of lower part series board of the fuel aggregate of expression the present invention the 39th embodiment;

Figure 54 is the amplification profile diagram of the shape of expression the present invention the 40th embodiment;

Figure 55 is the skiagraph of fuel aggregate;

Figure 56 is the planimetric map of the Network Dept. of bottom tie-plate;

Figure 57 is the lower part series board main portion amplification profile diagram of former fuel aggregate;

Figure 58 is the amplification profile diagram of the major part of the fuel aggregate lower part series board that is provided with the snotter trap setting in the past.

The embodiment of invention

Below, with reference to accompanying drawing 1～Figure 54, the embodiment of fuel aggregate of the present invention is described.Wherein, the member identical with former fuel aggregate used with Figure 55～Figure 56 same-sign and described.

The 1st embodiment (Fig. 1)

Fig. 1 is the overall diagram of expression by the fuel aggregate structure of present embodiment formation.As shown in Figure 1, this fuel aggregate is many fuel rods 2 and at least 1 water bar (ワ オ- ロ Star De) 3 are contained in the tubular trough of belt box 1 and constitute.Upper and lower end parts branch at this fuel aggregate wears top tie-plate 4 and bottom tie-plate 5, and the upper and lower end parts of fuel rod 2 and water bar 3 is by upper end plugs 6 and bottom end plug 7 and be separately fixed on top tie-plate 4 and the bottom tie-plate 5.And on water bar 3 vertically sky open certain intervals ground a plurality of liners 8 be installed, by these liners 8 fuel rod 2 is supported to permutation, and suppresses the bending of fuel rod 2.

In having the present embodiment of said structure, be opened at oral area bottom tie-plate 5 lower central coolant entrance hole 5a the position, be provided with vertical cylinder 21, this cylinder 21 from the bottom of bottom tie-plate 5 to up and down roughly the upright upper and lower side in pars intermedia ground all be opening.Bottom in this cylinder 21 is provided with the helical blade 22 that cooling medium a is formed rotating flow.This helical blade 22 has along the vertical direction center hub 23, equally spaced is arranged on a plurality of blades 24 around the center hub 23, combine with the inside surface of cylinder 21 with the outer edge of processes such as welding, form the structure that cylinder 21 is configured in the downstream of helical blade 22 thus each blade 24.In addition, the lower inner surface of bottom tie-plate 5 is made towards the diminishing taper of below diameter, and make peace the greatly smallest diameter portion of inside surface of lower part series plate 5 of the diameter of the outside surface of cylinder 21 is identical.Thus, form snotter recoverer 25, it is to make along with cooling medium a flow into snotteres in the bottom tie-plate 5 together to fall on the inside surface of bottom tie-plate 5 of cylinder 21 outer lower portion.

When adopting this structure, cooling medium a as shown by arrows, from the below of bottom tie-plate 5, flow in the cylinder 21 through coolant entrance hole 5a.By the bottom at cylinder 21 helical blade 22 is set, the cooling medium a that is made inflow by each blade 24 of helical blade 22 forcibly rises while rotate in cylinder 21 with the composition of going up rotation.

In case there is snotter to be mixed among the cooling medium a, rotate in cylinder 21 by cooling medium a, make the density snotter higher move to outer circumferential side, rise rotatably along the inside surface of cylinder 21 than cooling medium a by centrifugal force, after the upper end outflow of cylinder 21, it is released to radial outside.At this moment,, snotter is not risen, descend, be stacked into 25 li of snotter recoverers along cylinder 21 outsides because the ascending velocity of the cooling medium a in cylinder 21 outsides is slower.

Therefore, if adopt present embodiment, owing to make the cooling medium a of inflow be with the rotational flow composition, thereby can prevent that snotter is blended in the fuel aggregate, can keep the viability of fuel cage walls.In the present embodiment, by being made, the applying unit of rotational flow composition has center hub 23 and 3 structures for example with the helical blade 22 of blade 24, the rotational flow composition that is added on the cooling medium a is increased, compared with the former prior art that flexed plate is arranged the deflection of a slice plate, can improve the separation rate of snotter, therefore can improve the seizure performance of snotter from refrigerated separation.In addition, helical blade 22 is compared with the above-mentioned structure with flexed plate, owing to can dwindle blade angle, thereby can reduce the occlusion rate of stream; Again because can reduce the contact area of cooling medium and works, so can reduce the pressure loss.Also owing to structurally can increase the welding position of helical blade 22 and cylinder 21, thereby can improve their assembling intensity, can reduce because of combination separates the possibility that influences function, or, for example can reduce the possibility that vibration takes place the possibility that applying of rotational flow composition exerts an influence.

The 2nd embodiment (Fig. 2)

Fig. 2 is the enlarged drawing of biopsy cavity marker devices ground expression by the lower die board of the fuel aggregate of present embodiment formation.

As shown in Figure 2, in the present embodiment, though it is roughly identical with above-mentioned the 1st embodiment to execute the basic structure of the moving composition applying unit of turn of tidal stream, but it is on the bottom of fuel aggregate tie-plate 5 helical blade 22 to be set, be arranged on cylinder 21 around the helical blade 22, with being assembled into cancellate many wireform ramify structures.

When adopting this structure, because the cooling medium a that flows into also flows to outer circumferential side by the wall of cancellous cylinder 21, thereby cooling medium a flow path area is increased, can further reduce the pressure loss.

The 3rd embodiment (Fig. 3)

Fig. 3 is the enlarged drawing of biopsy cavity marker devices ground expression by the lower die board of the fuel aggregate of present embodiment formation.

As shown in Figure 3, in the present embodiment, though cylinder 21 is made and the same areolation of above-mentioned the 2nd embodiment, it is that the upper lateral part circumferential wall 21a of cylinder 21 is formed the section engrail of inside all sides and outer circumferential side is concavo-convex.

When adopting this structure, because cylinder 21 is made areolation, thereby the pressure loss when cooling medium a is flowed into reduces, and with centrifugal force when having applied snotter among the cooling medium a of rotational flow composition by helical blade 22 and shifted onto on the inside surface of cylinder 21, snotter is captured on the inside surface of jog on cylinder 21 tops.Therefore, if adopt present embodiment, can improve the capture rate of snotter.

The 4th embodiment (Fig. 4)

Fig. 4 is the amplification profile diagram of expression by the lower die board of the fuel aggregate of present embodiment formation.

Present embodiment is on the architecture basics of the fuel aggregate shown in above-mentioned the 1st embodiment, and near the inner peripheral surface side cylinder 21 upper ends, the snotter that highlightedly ring-type is set are caught with hook portion 26.This snotter is caught with angling portion 26 to be made of smooth annular body part and outshot, and the former is contacted with the top inner peripheral surface of cylinder 21; The latter be from this annular body part outstanding down and also with the inner peripheral surface of cylinder 21 facing to.

When adopting this structure, it is to remove on the basis of effect at the snotter shown in above-mentioned the 1st embodiment, with centrifugal force density than cooling medium high snotter pile under the state of inner peripheral surface side of cylinder 21, when the inside surface of cylinder 21 rises, snotter is trapped cylinder 21 and snotter catch, the snotter capture rate is further improved with in the corner recess space between the outshot of hook portion 26.

The 5th embodiment (Fig. 5)

Fig. 5 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is that the cylinder 21 upper end side undergauges in the bottom tie-plate 5 of the fuel aggregate shown in above-mentioned the 1st embodiment are become taper, also its upper end side is formed the minor diameter 21b of one section minor diameter tubular.

Adopt this structure to remove on the basis of effect at the snotter shown in above-mentioned the 1st embodiment, make the snotter that rises with cooling medium a along cylinder 21 inside surfaces that forms rotational flow, in the minor diameter 21b of cylinder 21, pass through under the state of more close perisporium, and after this, when it separates from the upward flow of cooling medium a and falls, through owing to forming the upper space that minor diameter 21b becomes more roomy snotter recoverer 25, can catch snotter better.Thereby can further improve the snotter capture rate.

The 6th embodiment (Fig. 6)

Fig. 6 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is on the architecture basics of the described fuel aggregate of above-mentioned the 1st embodiment, and the 2nd section small diameter cylinder 27 is set above cylinder 21.And the diameter of the cylinder 27 by making epimere is littler than hypomere cylinder 21, forms the gap 28 of ring-type.

When adopting this structure, owing in uphill process, can discharge from the gap 28 of ring-type along the snotter that cylinder 21 inside surfaces rise, thereby snotter promptly flows into snotter recoverer 25, can prevent effectively that thus snotter is blended in the fuel aggregate.

Also can above cylinder 21, set gradually the small diameter cylinder body more than 3 sections that does not have expression among the figure.

The 7th embodiment (Fig. 7)

Fig. 7 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

This embodiment be above the cylinder 21 shown in above-mentioned the 1st embodiment, empty along the vertical direction the 2nd roughly the same cylinder 29 of diameter of opening the configuration of certain intervals ground and cylinder 21, this 2nd cylinder 29 is supporting in combination by the assembly wall 30 of level and the inside surface of bottom tie-plate 5.

When adopting this structure, inside surface by the effect of rotational flow composition along cylinder 21 rotates the cooling medium a of rising and snotter with which, direct into outer circumferential side from the upper end of cylinder 21 and the gap of the 2nd cylinder 29, and the assembly wall 30 that is subjected to level positively stops and flows into snotter recoverer 25, is hunted down at this.And captive snotter falls downwards because of high density, can not be drawn into once more in the cooling medium main flow.Therefore, can more positively catch snotter with present embodiment, and with its maintenance.

The 8th embodiment (Fig. 8)

Fig. 8 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

This embodiment is that distortion has been done in the structure of the inner structure of the bottom tie-plate 5 of the fuel aggregate shown in above-mentioned the 1st embodiment, cylinder 21 and the configuration of helical blade 22 etc.Promptly, as shown in Figure 8, though the diameter of cylinder 21 bottoms is roughly certain, but the taper wide diameter portion 21c that (downstream), diameter increase is gradually made upward on top, with the perisporium at the suitable position of bottom level of snotter recoverer 25 on, offer a plurality of fenestras 31 along circumferential compartment of terrain.And hook-type projection 32 is set above cylinder 21 highlightedly, it is outstanding and close on downside minor diameter taper in the upper end open portion of cylinder 21 from the inside surface of bottom tie-plate 5.

This hook-type projection 32 forms ground, annular gap covers shape from upside bending cylinder shape with the superjacent air space of the upper end periphery of cylinder 21, the diameter of leading section little by little diminishes towards the below, formation is also littler than the periphery of cylinder upper end open portion, and extend in this peristome.In addition, helical blade 22 is configured in than on the also high position of the fenestra 31 of cylinder 21.

When adopting this structure, cooling medium a flow into after 21 li of the cylinders, add the rotational flow composition and rise by helical blade 22 along the inside surface of cylinder 21, with the moving part of the swashes of wave takes place from the outstanding hook-type projection that is provided with 32 of the inside surface of bottom tie-plate 5, be guided the outer circumferential side of cylinder 21 along the bottom of hook-type projection 32, snotter is fallen snotter recoverer 25 here.After this, snotter again from the fenestra 31 of cylinder bottom by being pushed into the inside of cylinder 21, in cylinder 21, rise again.Make snotter outer circulation in cylinder 21 thus, thereby more snotter can be collected in the bottom tie-plate 5, can also can prevent efficiently that thus snotter is mixed in the fuel portion with present embodiment.

The 9th embodiment (Fig. 9)

Fig. 9 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is on the fenestra 31 of cylinder 21 bottoms (upstream side) set in the bottom tie-plate 5 of the fuel aggregate shown in above-mentioned the 8th embodiment net 33 that snotter is caught usefulness to be set.

When adopting present embodiment, net 33 can be captured in the round-robin snotter in bottom tie-plate 5 described in above-mentioned the 8th embodiment, snotter can be remained on the snotter recoverer 25.

The 10th embodiment (Figure 10)

Figure 10 is the amplification profile diagram of expression by the bottom tie-plate of the fuel aggregate of present embodiment formation.

Present embodiment is on the architecture basics of the fuel aggregate shown in above-mentioned the 1st embodiment, near the perisporium upper end of cylinder 21, curl or skewed many slits 34 of offering.The sense of rotation of these slits 34 is that the sense of rotation of the cooling medium a that applied with helical blade 22 is consistent.

When adopting this structure, remove on the basis of effect at the described snotter of above-mentioned the 1st embodiment, owing to be coupled with the rotational flow composition along cylinder 21 inside surfaces, rotate the snotter of rising together with cooling medium a, be discharged to the outside of cylinder 21 by the spiral fashion slit 34 consistent with sense of rotation, thereby can be recovered to 25 li of snotter recoverers to snotter effectively.Therefore, present embodiment can prevent effectively that snotter is blended in the material aggregate.

The 11st embodiment (Figure 11)

Figure 11 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is to replace the slit 34 shown in above-mentioned the 10th embodiment, near the perisporium upper end of cylinder 21, offer a plurality of circular holes 35 to cross arrangement.

Adopt this structure also can with above-mentioned the 10th embodiment similarly, the snotter that will be by the effect of rotational flow composition rotates rising along cylinder 21 inside surfaces, with cooling medium a is discharged to the outside of cylinder 21 from the circular hole 35 of cross arrangement, can prevent effectively that snotter is blended in the fuel aggregate.

The 12nd embodiment (Figure 12)

Figure 12 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is on the basis of the described fuel aggregate of above-mentioned the 10th embodiment, opens the cylindric outside cylindrical 36 that is provided with gap at the outside sky of the cylinder 21 that slit 34 is arranged.The upper end of outside cylindrical 36 is provided with the upper end of inside cylindrical 21 with being connected, and the bottom of outside cylindrical body 36 is provided with bottom tie-plate 5 with being connected.Thus, the gap between cylinder just constitutes snotter recoverer 25a.

When adopting this structure, with above-mentioned the 10th embodiment similarly, the snotter that can will be by the effect of rotational flow composition rotates rising along cylinder 21 inside surfaces, with cooling medium a is discharged to the outside of cylinder 21 through spiral fashion slit 34, snotter is recovered to and snotter recoverer 25a that the gap of 36 of outside cylindrical constitutes in.And under the occasion of present embodiment, owing to constitute dual cylindrical structure, thereby can improve structural strength with cylinder 21 and outside cylindrical 36, can improve the bearing strength of helical blade 22 and to the oscillation intensity of rotational flow etc.

The 13rd embodiment (Figure 13)

Figure 13 (a) is the cross-sectional view that is illustrated in cylinder set in the bottom tie-plate of the fuel aggregate that forms by present embodiment enlargedly, and Figure 13 (b) is the oblique view of the cylinder state seen from the inboard of biopsy cavity marker devices ground expression.

Present embodiment is similarly to constitute dual cylinder with fuel aggregate shown in above-mentioned the 12nd embodiment, near the top of inside cylindrical body 21, offer many along with the corresponding to skewed or spiral helicine slit 34 of the rotational flow direction (direction of arrow) of cooling medium a, and the guide plate 37 that section becomes " L " font is set respectively along the downside inclination edge portion of each bar slit 34 of these cylinder 21 inside surfaces, be used for cooling medium a and snotter are directed into 34 li of slits.

When adopting this structure, can remove on the basis of effect at the described snotter of above-mentioned the 12nd embodiment, when the snotter that rotates rising along cylinder 21 inside surfaces, with cooling medium a by the effect of rotational flow composition arrives slit 34 positions, by guide plate 37 it is directed into 34 li of slits, make snotter be discharged to the outside of cylinder 21 smoothly, can further improve the efficient of catching snotter thus.

The 14th embodiment (Figure 14,15)

Figure 14 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Though present embodiment has the dual cylindrical structure that is similarly formed by inside cylindrical body 21 and outside cylindrical 36 with the described fuel aggregate of above-mentioned the 12nd embodiment, but, on inside cylindrical body 21, replace slit 34 ground, with the 11st embodiment similarly be configured to the identical circular hole 35 of a plurality of diameters of cross-like and, in the present embodiment, the center hub 23 of helical blade 22 is made the structure that more prolongs to the downstream of blade 24 than above-mentioned a plurality of embodiments.

When adopting this structure, also can with the 2nd embodiment similarly, by the rotational flow composition, to rotate the snotter of rising with cooling medium a along the inside surface of cylinder 21, be discharged to the outside of inside cylindrical body 21 from the circular hole 35 of staggered arrangement, snotter can be recovered to thus above-mentioned by and 25 li of the snotter recoverers that constitute of the gap of 36 of outside cylindrical.

Figure 15 be before the expression being provided with the snotter recovery structure that reverses plate and by the snotter separation rate (Figure 15 (a)) of the snotter recovery structure that is provided with helical blade 22 of this form of implementation and the chart of the pressure loss (Figure 15 (b)).

Characteristic shown in Figure 15 (a) and Figure 15 (b) is from parameters such as simulation flow of actual device and snotter shapes, tests resulting result and derive, expression snotter separation rate, this two aspect of the pressure loss, present embodiment and with the proportionate relationship of preceding example.Shown in structure Figure 58 of preceding example, the plate that 90 degree reverse is installed in cylinder.In addition, the guide member that the snotter that does not have expression among the figure falls usefulness is set on cylinder top.Relative therewith, present embodiment be in cylinder 21, install the helical blade 22 of 3 blade constructions, with center hub 23 extend to blade 24 the downstream, snotter recoverer 25a is made space between dual cylinder etc.Therefore, on the basis of reversing plate and this textural difference of helical blade, add the caused influence of structure of snotter recoverer 25a again.

Shown in Figure 15 (a), it is with preceding example 2.7 times that the snotter that is formed by present embodiment separates.But shown in Figure 15 (b), the ratio of the pressure loss of present embodiment is but than increasing with preceding example.This is considered to because constitute snotter recoverer 25a with the space between the dual cylinder, and 25a will form the structure that does not have coolant outlet with the snotter recoverer.But just because snotter recoverer 25a is made the structure of obturation, thereby snotter can not flow out with cooling medium, can improve the snotter capture rate thus.

The 15th embodiment (Figure 16)

Figure 16 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

The structure of the fuel aggregate shown in present embodiment and above-mentioned the 14th embodiment similarly, near the top of inside cylindrical body 21, offer a plurality of circular holes 35.But it is certain these circular holes 35 not to be made the aperture, but makes the aperture of circular hole bigger in the aperture of cylinder upper side (downstream), and the aperture of lower side (upstream side) changes lessly.

According to this structure, when snotter is big, because inertia effect, there is certain hour at the perisporium place that arrives cylinder 21, relative therewith, snotter is hour easy perisporium place that arrives cylinder 21, and utilizing snotter is to change this point accordingly with its size from the distance that helical blade arrives cylindrical wall, set its circular hole that arrives cylindrical wall place footpath mutually in phase with each snotter size, can catch snotter efficiently thus.

The 16th embodiment (Figure 17)

Figure 17 is the oblique view of the part of the dual cylinder in the bottom tie-plate of representing to form by present embodiment with biopsy cavity marker devices, enlargedly.

Present embodiment has the dual cylindrical structure shown in above-mentioned the 12nd～15 embodiment, and it is in this structure, and the cylinder 21 of inboard and the upper end connecting portion 38 of outside cylindrical 36 are made eyed structure.Though Figure 17 represents to have the occasion of slit 34, this is same with the occasion of circular hole 35.

According to this structure, owing to flow into as the cooling medium a of 25 li of the snotter recoverers in space between cylinder with after snotter separates from inside cylindrical body 21, flow out upward through the upper end of eyed structure connecting portion 38, thereby flow of coolant become level and smooth, can improve the snotter capture rate, can reduce the pressure loss by increasing stream simultaneously.

The 17th embodiment (Figure 18,19)

Figure 18 represents the amplification profile diagram by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment has the dual cylindrical structure shown in above-mentioned the 12nd～15 embodiment, and it is in this structure, forms coolant flow path 39 between the bottom of outside cylindrical 36 and bottom tie-plate 5.This coolant flow path 39 can be as shown in figure 18, reduce by the sagging length with outside cylindrical 36, and and sky is opened certain interval and is formed between the bottom tie-plate 5, also can make outside cylindrical 36 and 5 combinations of bottom tie-plate, form by near the bottom of outside cylindrical 36, offering the hole.

If adopt this structure, then flow to outside cylindrical body 36 from the cooling medium a that slit 34 or circular hole 35 flow into the snotter recoverer 25a between inside and outside cylinder by coolant flow path 39 with snotter.At this moment, because flow into the flow of the cooling medium a of snotter recoverer 25a compares with the flow that cylinder 21 from the inboard flows upward from slit 34 or circular hole 35, measure less and flow velocity is also slower, thereby snotter is hunted down at snotter recoverer 25a, has only cooling medium a to flow to the outside of outside cylindrical body 36.

Present embodiment not only has the snotter shown in above-mentioned the 12nd～15 embodiment and removes effect, also because increased the stream of cooling medium, so can reduce the pressure loss.

Figure 19 is that the snotter separation rate (Figure 19 (a)) of the snotter recovery structure that is provided with coolant flow path 39 that being provided with the snotter recovery structure that reverses plate and forming by present embodiment before the expression and the pressure loss are than (Figure 19 (b)).

Characteristic shown in Figure 19 (a) and Figure 19 (b) be with the situation of the 14th embodiment similarly, with parameters such as the flow of simulation actual device and snotter shapes, test the result who obtains and derive, expression snotter separation rate, this two aspect of the pressure loss, present embodiment and with the proportionate relationship of preceding example.Shown in Figure 58, the plate that 90 degree reverse is installed in cylinder with the structure of preceding example.In addition, the guide member that the snotter that does not have expression among the figure falls usefulness is set on cylinder top.Relative therewith, present embodiment is that the helical blade 22 of 3 blade constructions is installed in cylinder 21, with center hub 23 extend to blade 24 the downstream, snotter recoverer 25a is made space between dual cylinder, and form coolant flow path 39.

Shown in Figure 19 (a), the snotter separation rate that is formed by present embodiment is 2.4 times with preceding example approximately.And shown in Figure 19 (b), the pressure loss of present embodiment compares and compares with preceding example, reduces about 1/2.This is considered to because different with above-mentioned the 14th embodiment, though snotter recoverer 25a is formed space between dual cylinder, but form coolant flow path 39 in this snotter recoverer 25a, cooling medium a can flow out to the foreign side of outside cylindrical 36 smoothly by this coolant flow path 39.

The 18th embodiment (Figure 20)

Figure 20 is the enlarged drawing of expression by the lower part series board of the fuel aggregate of present embodiment formation.

As shown in figure 20, present embodiment is that the cylinder 21 with the fuel aggregate shown in above-mentioned the 1st, the 5th, the 10th and the 11st embodiment is an object, and the affix snotter falls with guide body 40.Though the structure of Figure 20 basic representation the 1st embodiment, but when other the 5th, the 10th, the 11st embodiments of expression is same substantially, be snotter to fall with guide body 40 are interior periphery and the crown members top, central opening that surround ora terminalis on the cylinder 21, be installed in the top of cylinder 21 by the skies such as support that do not have expression among the figure with opening certain intervals.That is to say, this snotter falls with the smooth ring portion 40a of the top that is configured in ora terminalis on the cylinder 21 on the guide body 40 and sagging from the interior outer peripheral edges of this ring portion 40a, roughly parallel with the round outer peripheral face of ora terminalis on the cylinder 21 inside and outside 1 couple of tubular dip portion 40b, 40c and constitutes; Can make and become outer circumferential side along the upward flow of the cooling medium a of the inner peripheral surface of cylinder 21 and down flow.

When adopting this structure, along the inner peripheral surface of cylinder 21, while the snotter that circles round and rise with cooling medium a, in the upper end of cylinder 21, fall to be directed to along outer circumferential side by snotter and flow downward, and be stacked on 25 li of snotter recoverers with guide body 40.

The 19th embodiment (Figure 21,22)

Present embodiment is that the snotter shown in the 18th embodiment falls the application examples with guide body 40, and Figure 21 is its structure section figure, and Figure 22 is an enlarged drawing of at length representing major part.

Present embodiment such as Figure 21 and shown in Figure 22, fallen with the gap between the upper end outer peripheral face of the inner peripheral surface of the outside tubular dip portion 40c of guide body 40 and cylinder 21 by crown snotter and to form the decline stream, relative mobile in this decline stream is provided with a plurality of snotter capture boards 41.Promptly, foreign material capture board 41 is made of a plurality of such as tongue-shaped plate face, mutually be arranged in across outside tubular dip portion 40c inner peripheral surface and with the outer peripheral face of its cylinder 21 vis-a-vis on, and each plate is facing relative vertical direction with the decline stream and is being provided with highlightedly.

When adopting this structure, along the inner peripheral surface of cylinder 21 and the snotter that rises fall with guide body 40 by snotter and direct under the outer circumferential side of circle 21, the occasion of piling up, when the rotation composition that forms at helical blade 22 is big or the density of snotter hour, might snotter rolled-up once more from the decline circuit portion, flow out with cooling medium a as main flow, present embodiment can prevent this accident, therefore can improve the snotter capture rate with snotter capture board 41.

The 20th embodiment (Figure 23,24,25)

Present embodiment be about the snotter capture board 41 shown in the 19th embodiment change the shape example, Figure 23, Figure 24 are the enlarged drawings of each different configuration example of expression with Figure 25.

In the example shown in Figure 23, fall with guide body 40 and cylinder 21 outstanding snotter capture boards 41 from snotter and to have with raising towards leading section inclination and the structure that erects gradually.

In the example shown in Figure 24, snotter capture board 41 roughly is a level, leading section make be bent into " L " font make progress hook-shaped.

In the example shown in Figure 25, it is tabular that snotter capture board 41 is made semicircular arc bending upwards.

Can both form the snotter trapped state to capture board 41 really with above-mentioned these structures.

The 21st embodiment (Figure 26)

Figure 26 is the enlarged drawing of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is on the architecture basics of the fuel aggregate shown in above-mentioned the 17th～20 embodiment, snotter in snotter recoverer 25 falls with near the position outlet of guide body 40 and the periphery of cylinder 21, and the snotter that sets a plurality of needle-likes of sword mountain formula is caught fin 42.

When adopting this structure, have the snotter shown in above-mentioned the 17th～20 embodiment and catch effect, but sometimes when the rotation composition that is formed by helical blade is big or the density of snotter hour, snotter might be rolled once more, flow out with the cooling medium as main flow, thereby and the snotter seizure fin 42 of application sword mountain formula just can make snotter securely keep making capture rate to improve.

The 22nd embodiment (Figure 27)

Figure 27 is the enlarged drawing of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is on the basis of the fuel aggregate structure shown in above-mentioned the 17th～20 embodiment, along the whole above-below direction of bottom tie-plate 5, a plurality of ring-type jogs 43 along bottom tie-plate 5 inner peripheral surfaces are set.

When adopting said structure, have the snotter shown in above-mentioned the 17th～20 embodiment and catch effect, but when the rotation composition that forms at helical blade 22 is big sometimes or snotter density hour, snotter might be rolled once more and flows out with the cooling medium as main flow from snotter recoverer 25, and by the chase 43a of jog 43 is set on the inner peripheral surface of bottom tie-plate 5, the snotter of rolling can be caught, can improve the snotter capture rate.

The 23rd embodiment (Figure 28)

Figure 28 is the enlarged drawing of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is the chase 43a of the jog 43 of the bottom tie-plate inwall shown in above-mentioned the 22nd embodiment to be done the grooving porch is narrower, the inner more roomy shape of ditch.

When adopting said structure, can more positively catch the described snotter of rolling of above-mentioned the 22nd embodiment, therefore can improve capture rate.

The 24th embodiment (Figure 29,30,31)

Figure 29 is the integrally-built sectional drawing of expression by the fuel aggregate of present embodiment formation.

Present embodiment be the snotteres in the bottom tie-plate shown in above-mentioned the 17th～23 embodiment 5 fall make with the outside diameter d of guide body 40 also littler than the internal diameter of the coolant entrance hole 5a of bottom tie-plate 5 lower ends.Because correspondingly, the diameter of cylinder 21 also diminishes, thereby with the installation component 5b of ring-type cylinder 21 is removably mounted on the bottom tie-plate 5.In addition, present embodiment and the 14th embodiment similarly, the center hub 23 of helical blade 22 made the structure that prolongs to the downstream of blade 24.

When adopting this structure, can make independently with bottom tie-plate 5 because snotter falls with guide body 40, and the installation on bottom tie-plate 5 is also simpler and easy, thereby can reduces manufacturing cost.Again because can easily replace, so can also improve convenience such as maintenance maintenance.

Figure 30 represents that the snotter capture rate (Figure 30 (a)) with preceding example and present embodiment and the pressure loss are than (Figure 30 (b)).This figure and Figure 15 and Figure 19 are to be derived by parameters such as simulation flow of actual device and snotter shape, the result that tests similarly.The condition of reversing plate and helical blade etc. is with above-mentioned same.

Shown in Figure 30 (a), the snotter separation rate of present embodiment increases by 4.5 times that become with preceding example approximately, and and for example shown in Figure 30 (b), the pressure loss is than 4/5 before being reduced to approximately.

Figure 31 is illustrated in the circular hole 35 that forms on the cylinder 21 of structure shown in Figure 29 shown in the 11st embodiment.

Adopt this structure, similarly can separate the cylinder 21 that constitutes band circular hole 35 independently, can improve property easy to manufacture, can reduce cost, can easily replace with bottom tie-plate 5 with shown in Figure 29.

The 25th embodiment (Figure 32,33)

Present embodiment is different with above-mentioned each embodiment, and it is not use cylinder 21, and helical blade 22 is directly installed on the bottom tie-plate 5.

Figure 32 is the enlarged drawing of expression by the lower part series board of the fuel aggregate of present embodiment formation, and Figure 33 is the sectional drawing of obtaining along the A-A line of Figure 32.

Present embodiment shown in Figure 32,33, with above-mentioned the 1st embodiment in the diameter of employed much the same helical blade 22 do more slightly, be directly installed on the coolant entrance ostium 5a of bottom tie-plate 5 with welding.And a plurality of hook-type snotter capture boards 44 are set on the inside surface of bottom tie-plate 5, they are along the reverse direction of the rotating flow of the cooling medium a that causes with helical blade 22, give prominence to setting with making " L " font.

Even adopt this structure also can with above-mentioned each embodiment similarly, will be rotated into branch by helical blade 22 and be applied to cooling medium a (the containing snotter) lining that flows into from the lower end of bottom tie-plate 5, cause rotating flow.In this case, shift cooling medium a the inside surface of bottom tie-plate onto, can snotter be caught by the hook-type snotter capture board 44 that is arranged on the contrary on the inside surface of bottom tie-plate 5 with rotating flow.

Like this, adopt present embodiment also can bring into play the snotter capture function, particularly also get except cylinder 21, thereby can reduce the part number, can make designs simplification owing to present embodiment.

The 26th embodiment (Figure 34,35)

Present embodiment be the 25th embodiment change the shape example, the enlarged drawing of the lower part series board of Figure 34 fuel aggregate that to be expression form by present embodiment, Figure 35 is the sectional drawing of obtaining along the B-B line of Figure 34.

Present embodiment is made ocular structure to the hook-type snotter capture board 44 that is arranged on the inside surface of bottom tie-plate 5, its by frame section 44a and tensioning the mesh portion 44b that is arranged on the frame section constitute.

When adopting this structure, by helical blade 22 cooling medium a is pressed to the inside surface of bottom tie-plate 5, when the mesh portion 44b of the hook-type snotter capture board 44 of cooling medium a by forming eyed structure, snotter is caught by this part.

If adopt present embodiment because the snotter that once had been trapped on the mesh portion 44b is pushed by cooling medium, thereby difficult float from hook-type snotter capture board 44 float, can improve catching property.

The 27th embodiment (Figure 36,37)

Figure 36 is the one-piece construction of expression by the fuel aggregate of present embodiment formation, and Figure 37 is the sectional drawing of obtaining along the C-C line of Figure 36.

As Figure 36, shown in Figure 37, present embodiment is to make the structure of helical blade different with the structure shown in last the 1st embodiment to the 26 embodiments.The general charging guide member (with reference to the 1a of Fig. 1) that promptly, replaces the downward arch of bottom tie-plate 5 lower ends that are arranged on fuel aggregate, helical blade 47 is set in this section, it is blade more than 45 downward arches, that curl reverses to be arranged and the center hub 46 of extending upward from the central part of these blades, and this helical blade 47 is made into and has the function of charging with guide member.In bottom tie-plate 5, be provided with the same cylinder of Figure 29 21 and falling with guide body 40.

When adopting this structure, because the downstream of helical blade 47 is apart from lengthening, thereby the just easier inner peripheral surface along cylinder 21 of snotter flows, and snotter is the easier outside that flows to cylinder 21 just also, can improve the snotter capture rate.Also because helical blade 47 is structures of double as charging guide member, thereby can reduces the part number, can make the structure small compact.

Because present embodiment is the downstream that the center hub 46 of helical blade 47 is extended to blade 45, so can prevent the downstream central portion of helical blade 47 flowing of turbulent flow being taken place again, increase by the revolving force that makes cooling medium a, can improve the snotter capture rate.

The 28th embodiment (Figure 38,39)

The enlarged drawing of the lower part series board of Figure 38 fuel aggregate that to be expression form by present embodiment, Figure 39 (a) and (b) be respectively the D of Figure 38 to view and E to view.

As shown in these figures, present embodiment is to replace the helical blade 22,47 shown in the respective embodiments described above, 5a position, coolant entrance hole in the lower end of bottom tie-plate 5 is provided with cylinder element 49, and it has many, 3 spiral flow path 48 (48a, 48b, 48c) for example.This cylinder element 49 be make the axle center along above-below direction be installed on the bottom tie-plate 5, each bar spiral flow path 48a, 48b, 48c are shown in Figure 39 (a) and (b), oral area is opened on the upper and lower end face of cylinder element 49, in the configuration mutually of the inside of cylinder element 49, form independent stream with reversing.And on the centrifugal action part of each bar spiral flow path 48a, 48b, 48c, form the concavo-convex ditch 50 vertical respectively with the flow direction of cooling medium a.In the present embodiment, also still between the inside surface of the outside of cylinder element 49 and bottom tie-plate 5, form snotter recoverer 25.

When adopting this structure, cooling medium a flow in each bar spiral flow path 48a, 48b, the 48c from the lower end side of cylinder element 49, and the upper end side from this cylinder element 49 under the state that has increased rotational flow is ejected in the bottom tie-plate 5.Under this occasion, in each bar spiral flow path 48a, 48b, 48c,, can prevent that snotter is blended in the fuel by concavo-convex ditch 50 parts of centrifugal action on cooling medium a are caught snotter.And, owing in cylinder element 49, do not have captive snotter, adding by each bar spiral flow path 48a, 48b, 48c under the state that flows of rotation, from cylinder element 49 discharges, thereby can flow outside side by centrifugal action, can be captured to 25 li of snotter recoverers.

So present embodiment energy and the respective embodiments described above prevent effectively that similarly snotter is blended in the fuel, can catch the snotter of sneaking in cooling medium a effectively.

The 29th embodiment (Figure 40～43)

The lower part series board of Figure 40 fuel aggregate that to be expression form by present embodiment put figure, Figure 41 is the sectional drawing of obtaining along the F-F line of Figure 40, Figure 42 is the sectional drawing of obtaining along the G-G line of Figure 40, Figure 43 is the amplification oblique drawing at position shown in Figure 42.

As shown in these figures, present embodiment is that the structure of the structure of bottom tie-plate 5 and rotating flow applying mechanism is different with the respective embodiments described above.That is, the coolant entrance hole 5a of bottom tie-plate 5 is minor diameters, nozzle 51 is set in this section, makes cooling medium a become high velocity stream and rises.The base station 52 of ring-type is set above this nozzle 51, and the center line that the flow limitation plate 53 of polylith lengthwise stands in great numbers at nozzle 51 and base station 52 on this base station 52 erects peripherally.As shown in figure 41, these flow limitation plates 53 bend to from plane one-tenth "＜" word shape (or circular-arc), each angle of bend all equates, we can say, such as the structure of the fixed blade of waterwheel, become when flowing radially from the position of center line of nozzle 51 at cooling medium a, flow limitation is become along "＜" oxbow angle ground to become the upper end of rotational flow at flow limitation plate 53, roughly close tight lid 54 at the central part of bottom tie-plate 5, the stream of fixing umbrella.The following therefrom mind-set periphery that this stream closes tight lid 54 bends to dome-shaped, cooling medium a after nozzle 51 rises, meet this stream close tight lid 54 below, forms slowly downward flowing and to outer circumferential side (sidewall of bottom tie-plate 5 is on one side) dispersion.When forming this dispersion train, rotational flow is added on the cooling medium a by above-mentioned polylith flow limitation plate 53.On the side wall inner surfaces of bottom tie-plate 5,, the marmon clamp foreign material capture element 56 of many chases 55 that have longitudinally is being set from the lower end to the upper end as Figure 42 and shown in Figure 43.

When adopting this structure, cooling medium a becomes upward flow from the hole of nozzle 51 and after being directed in the central part of bottom tie-plate 5, conflict and change direction owing to closing tight lid 54 with stream, in the time of outside becoming radial flowing out to downwards, form rotational flow by flow limitation plate 53, after this become crosscut and cross the flowing of chase 55 of the snotter capture element 56 of bottom tie-plate 5 inside surfaces, be fed to fuel-side.At this moment, sneak in the snotter in cooling medium a, bigger snotter is caught by the stream confinement plate 53 that stands in great numbers on nozzle 51, remains on the central part of bottom tie-plate 5.The snotter of less shape by flow limitation plate 53, become to flow downward and flow out to after the outer circumferential side, form the state that from flow, falls by underspeeding.And separate, caught by the chase 55 of snotter capture element 56 from the cooling medium a that rotating.

Present embodiment can be carried out the high efficiency of snotter as described above and be caught.

Present embodiment has the necking down mechanism of the cooling medium a necking down that will flow into because nozzle 51 is set, thereby the flow path resistance on the stream increases; Because resistance reduced when flow became big, thereby can improve the discharge stability that cooling medium flows to fuel aggregate.

The 30th embodiment (Figure 44)

Figure 44 is the integrally-built sectional drawing of expression by the fuel aggregate of present embodiment formation.

Present embodiment be replace the cylinder 21 shown in the respective embodiments described above and as rotational flow apply member helical blade 22, tabular snotter be set remove plate 58, it is offering a plurality of small diameter bore 57.This snotter is removed plate 58 and is located in the bottom tie-plate 5 obliquely, stops snotter to pass through with respect to the main flow direction (vertical direction) of cooling medium a.And remove the upper end side of plate 58 at snotter, promptly at the lower position of inclined-plane apex 59, inner surface portion from bottom tie-plate 5 is being set, is removing the prominent wall 60 that plate 58 erects, forming by this prominent wall 60 and be used for reclaiming the snotter recoverer 61 of removing the snotter that plate 58 falls from snotter towards snotter.

When adopting this structure, cooling medium a is from side inflow lower part series plate 5 down, removes small diameter bore 57 on the plate 58 by being arranged on snotter, and then flows into the inside of trough of belt box 1 by Network Dept. 9.After this, for example when construction, metal fillings such as the tinsel of sneaking into enter into 5 li of bottom tie-plates along cooling medium a, but remove plate 58 by the snotter that is arranged on these bottom tie-plate 5 inside metal fillings are caught, and are transported to the apex 59 on inclined-plane by the fluid force of cooling medium a.

Below the apex 59 on this inclined-plane, constitute snotter recoverer 61, form the choking portion that cooling medium a flows.Therefore by the mobile acting force that forms of cooling medium a the metal fillings of transporting to inclined-plane apex 59 is diminished, be deposited in 61 li of snotter recoverers with regard to falling.

And because atomic pile operating condition difference, the flow velocity because of cooling medium a is big sometimes, and little metal fillings does not fall from inclined-plane apex 59.Even this metal fillings also can when perhaps stopping flow of coolant in prophylactic repair, make metal fillings be stacked into 61 li of snotter recoverers when reactor forms the flow velocity reduction of low output state, cooling medium.

Therefore, can prevent that similarly snotter is immersed in the fuel aggregate with the respective embodiments described above, can keep the performance that perfects of fuel cage walls with present embodiment.

The 31st embodiment (Figure 45)

Figure 45 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is that the snotter that replaces the fuel aggregate shown in above-mentioned the 30th embodiment is removed plate 58, be provided with from the center of bottom tie-plate 5 to periphery gradually the snotter of standing shape remove plate 62.Promptly, the snotter inclined-plane of removing plate 62 is that the axis of centres of fuel aggregate is constituted as the summit, snotter recoverer 61 be arranged on bottom tie-plate 5 around.Other structures are identical with the 30th embodiment.

When adopting this structure, because snotter is removed the chamfer length of plate 62, that is, removed plate from snotter by snotter and catch the displacement that begins to reclaiming and be shortened, thereby can improve the snotter recovery.

The 32nd embodiment (Figure 46)

Figure 46 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is different with above-mentioned the 31st embodiment, and it is to constitute snotter from its center to the dip plane that periphery erects gradually and remove plate 63 by the supporting of the fuel of bottom tie-plate 5 upper ends is made below Network Dept. 9.Promptly the downside of network (ネ Star ト ウ-Network) portion 9 is made the inclined-plane, it can obtain the effect same with the 31st embodiment.

When adopting this real mode, though the angle on inclined-plane is littler than the 31st embodiment, metal fillings seldom is subjected to the vibration effect of ANALYSIS OF COOLANT FLOW formation, can transport to the summit 59 on inclined-plane really.Can keep the snotter capture effect same thus, and can make designs simplification by reducing member with the 31st embodiment.

The 33rd embodiment (Figure 47)

Figure 47 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment be different with above-mentioned the 30th～32 embodiment, the prominent wall 60 that constitutes the snotter recoverer 61 in the bottom tie-plate 5 is made air foil shape.

When adopting this structure, because prominent wall 60 is made air foil shape, thereby less by the mobile eddy current that forms of the cooling medium a on its rear side, can improve capture rate at snotter recoverer 61.

The 34th embodiment (Figure 48)

Figure 48 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of this real mode formation.

Present embodiment is to form coolant flow path 64 on the bottom end plug 7 on the bottom tie-plate 5 fuel rod 2 the lower end is bearing in, and it is that to make it become the roughly bending of fluidly circulating to the side after cooling medium a is risen rectangular.The mouth of the export department 65 of these coolant flow path 64 is opened in the upside space of limbers 11, and limbers 11 is provided in a side of in the Network Dept. 9 of bottom tie-plate 5.Export department's shape of coolant flow path 64 is made into such as regards parallel wire from the side as.This export department's shape can be made "＜" word shape, " L " word shape, " S " word shape or ring-type.

When adopting this structure, cooling medium a rises by the coolant flow hole 11 of Network Dept. 9 and the coolant flow path 64 of bottom end plug 7 from bottom tie-plate 5.Because the shape of coolant flow path 64 meets at right angles with respect to the flow direction general curved, thereby metal fillings flows through coolant flow path 64 in the time, for example the metal fillings that iron wire is grown like that flows out from stream, is trapped in the bottom end plug 7.Owing on the basis of limbers 11, again coolant flow path 64 is set, thereby can reduce the fluid loss on the bottom tie-plate 5, by reducing fluid loss, can be increased in the flow of flowing coolant a in the trough of belt box 1, can improve the thermal efficiency of fuel.

The 35th embodiment (Figure 49)

Figure 49 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is that the structure that does not all have the limbers at bottom end plug support holes 9a position is in addition made by the Network Dept. 9 of bottom tie-plate 5, and on bottom end plug 7, form coolant flow path 66, it is after cooling medium a is risen, and it is formed to the side fluidly circulate and bending.

When adopting this structure,, thereby can improve the capture rate of snotter because cooling medium a only passes through coolant flow path 66.

The 36th embodiment (Figure 50)

Figure 50 is the enlarged drawing of expression by the bottom end plug 7 of the fuel aggregate of present embodiment formation.

Present embodiment is the shape of the export department 65 of the coolant flow path that forms on the bottom end plug 7 for example to be made the side see it is "＜" font.Also can make other " L " fonts, " S " font, " T " font or crank shape.

The 37th embodiment (Figure 51)

Figure 51 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment is that a plurality of main flow directions with respect to cooling medium a of alternate configurations tilt in the inner space of bottom tie-plate 5 snotteres are sneaked into and prevented plate 67.

When adopting this structure, just in case snotter is blended among the cooling medium a and flow into 5 li of bottom tie-plates, owing to snotter is sneaked into and prevented that plate 67 from alternately disposing, thereby move with crawling on cooling medium a limit, Bian Shangsheng.Again because the density of snotter than cooling medium a height, so by the inertial force effect, can not change direction at once, flows to the wall side in the bottom tie-plate 5, be trapped in to sneak into and prevent in the chevron zone that plate 67 forms by wall and snotter.Iron wire elongated snotter like that can not be sneaked into the gap that prevents plate 67 by snotter, can prevent that snotter from flowing in the fuel aggregate, can keep the performance that perfects of fuel cage walls.

The 38th embodiment (Figure 52)

Figure 52 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Present embodiment and above-mentioned the 37th the embodiment similarly snotteres that tilt of a plurality of main flow directions with respect to cooling medium a of alternate configurations are sneaked into and prevented plate 67, and be all crooked upward but these snotteres are sneaked into each front end 68 of preventing plate 67.

When adopting this structure, increase the effect that the snotter that inertial force is high directs into the wall side of bottom tie-plate 5.Like this, just in case snotter is sneaked in cooling medium a, when being guided 5 li of bottom tie-plates, snotter can be sneaked into by snotter and be prevented that plate 67 from stoping, and can not flow in the fuel aggregate, can keep the viability of fuel cage walls.

The 39th embodiment (Figure 53)

Figure 53 is the amplification profile diagram of expression by the lower part series board of the fuel aggregate of present embodiment formation.

Snotter in the present embodiment is sneaked into and is prevented that plate 67 from being made of the sheet material of roughly one-tenth " V " font of many arranged spaced, the both ends separately of these sheet materials are that the inside surface with bottom tie-plate 5 is provided with in contact, form the peristome 69 that flow of coolant is become crawl stream on the position not overlapping of each sheet material.

When adopting this structure, cooling medium a prevents that along snotter plate 67 from flowing to the wall side of bottom tie-plate 5, sneaking into the peristome 69 that prevents plate 67 from snotter and flow into to the direction of fuel rod 2.Therefore, with about alternately overlapping snotter sneak into the occasion that prevents plate and compare, can increase number, catch the position by crawl number of times and the snotter that increase cooling medium a, can improve the effect of catching snotter.

Because the position of peristome 69 is sneaked into because of each snotter and is prevented that plate 67 differences thereby cooling medium a from just crawling, just in case sneaking among the cooling medium a, snotter flow into 5 li of bottom tie-plates, high density inclusions can not flow to the wall side along with crawling of cooling medium a yet, can sneak into the chevron zone seizure that prevents that plate 67 from forming by wall and snotter.

Again owing to snotter sneaked into prevent that plate 67 from making " V " font, thus can increase overlapping number, crawl number of times and the snotter that can increase cooling medium a catch the position.Therefore can sneak into snotter and prevent that baffle-wall from ending snotter, it is not flowed in the fuel aggregate, can keep the viability of fuel cage walls.

The 40th embodiment (Figure 54)

Figure 54 is the enlarged drawing of expression by many rill shapes of present embodiment formation.

Present embodiment is to form cooling medium along many rills 70 that flow on the bottom of the fuel aggregate shown in the respective embodiments described above tie-plate, cylinder, snotter fall with the surface of guide body, hook-type capture board and helical blade etc.Rill 70 can have " V " font shown in " U " font shown in Figure 54 (b) or Figure 54 (c).

At the height h that adopts rill 70 with when d equates with the thickness δ 1 of turbulent viscous sublayer at interval, be the friction loss of the suitableeest reduction cooling medium on wall.The thickness δ 1 of viscous sublayer at this moment is called best rill amplitude, promptly,

(numerical expression 1)

δ 1=h (rill height)=d (at interval)

This best rill amplitude δ 1 is determined by the flow velocity of cooling medium and coefficient of viscosity, is provided by following formula.

(numerical expression 2)

δ1＝123×(D/2)/(uD/γ) ^(7/8)

Wherein: u is the flow velocity of turbulent flow

D is a barrel bore or bottom tie-plate waterpower diameter of equal value

γ is a coefficient of viscosity

Like this, by longitudinal furrow is set, and to make these longitudinal furrows be along ANALYSIS OF COOLANT FLOW direction, and the best ditch width of cloth obtained of useful above-mentioned numerical expression, the friction loss that flows into the cooling medium in the tie-plate of bottom reduced, thereby reduce the pressure loss on the tie-plate of bottom.

As top in detail as described in, the present invention sneaks into measures such as preventing plate by snotter is set in the tie-plate of bottom, can produce can stop the snotter that flows with cooling medium to flow in the fuel aggregate, can keep the excellent results such as viability of fuel cage walls.

Claims (5)

1, fuel aggregate, it is the pile core portion that is loaded on the reactor pressure vessel of boiling water type atomic reactor, it has: many fuel rods; Support the top tie-plate and the bottom tie-plate of the upper and lower side of these fuel rods; The compartment of terrain is configured between above-mentioned two tie-plates, a plurality of liners at the above-mentioned fuel rod of maintenance interval each other; And the trough of belt box of the whole outer circumferential sides of above-mentioned these members of coating; Make the cooling medium that flows into from the lower end side of above-mentioned bottom tie-plate be passed to above-mentioned fuel rod side, it is characterized in that: be provided with helical blade and vertical cylinder as upward flow; Above-mentioned helical blade is the lower central position that is configured in above-mentioned bottom tie-plate, has center hub and a plurality of blade that the cooling medium that will rise forms rotational flow; Above-mentioned cylinder is the upper and lower side opening that uprightly arrives certain altitude in the downstream of this helical blade; And, outer lower portion at above-mentioned cylinder, inner face side at above-mentioned bottom tie-plate forms the snotter recoverer, it is to make the snotter in above-mentioned cooling medium flows into above-mentioned bottom tie-plate fall and be reclaimed, in the arranged outside outside of the cylinder in helical blade downstream out cylinder, form dual cylindric, and with the space obturation in the downstream of above-mentioned inside cylindrical body and outside cylindrical, and on the perisporium of above-mentioned inside cylindrical body, offer a plurality of spiral fashions or skewed slit or circular hole, and make can be recovered to the snotter that flows out from the slit of this cylinder or circular hole and outside cylindrical between the gap in.

2, fuel aggregate as claimed in claim 1 is characterized in that: opposite guide plate of catching usefulness to outstanding snotter with rotating flow is set on the slit inlet portion of being offered on the cylinder.

3, fuel aggregate as claimed in claim 1 is characterized in that: make the aperture that is opened in the circular hole on the cylinder, and different according to upstream and downstream.

4, as any described fuel aggregate in the claim 1,2 or 3, it is characterized in that: the upper end connecting portion in dual cylindrical portions may downstream is made eyed structure.

5, as any described fuel aggregate in the claim 1,2 or 3, it is characterized in that: the bottom of outside cylindrical is broken away from from the bottom tie-plate, form the inside and outside coolant flow path that is communicated with this outside cylindrical body.

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