JP5108493B2 - Sloshing suppression method - Google Patents

Description

  The present invention relates to a sloshing suppression method. More specifically, the present invention relates to a sloshing suppression method suitable for use in suppressing sloshing due to earthquake motion in, for example, a water intake tank or a storage tank.

  This is called sloshing where the stored liquid in the water intake tank or storage tank is greatly waved by long-period ground motion that is caused by long-period ground motions, especially long-period vibrations with long periods, due to earthquakes, etc. (also called liquid level fluctuations) ) Phenomenon occurs.

  For example, when sloshing occurs in a water intake tank used to store water that cools operating equipment, the intake of a pump that pumps cooling water below the intake limit water level, which is the design lower limit water level, is exposed. Then the pump sucks air. When the amount of sucked air increases, there is a problem that the performance of pumping by the pump is lowered and cooling efficiency is lowered, or pumping by the pump cannot be performed and cooling water cannot be supplied.

  As a conventional sloshing suppression device, for example, as shown in FIG. 16, an inner chamber 102 having an opening 104 opened toward the inside of the tank 103, and a storage liquid provided in the opening 104 toward the inner chamber 102. A check valve 105 that allows only the flow of 107, and an outflow hole 106 that is provided in the lower portion of the inner chamber 102 and discharges the stored liquid 107 taken into the inner chamber 102 toward the tank 103, When the storage liquid 107 in the tank 103 flows in a wave shape when sloshing occurs, the storage liquid 107 flows into the inner chamber 102 from the opening 104 to raise the water level in the inner chamber 102 and is provided in the opening 104. By closing the check valve 105, the stored liquid 107 that has flowed into the inner chamber 102 is prevented from flowing out of the inner chamber 102 through the opening 104, and the inner chamber 102 Is intended to early subsided sloshing by repeating the cycle of to flow out slowly into the tank 103 from the reservoir fluid 107 held in the inner chamber 102 by the water level is high at the same time the outflow hole 106.

JP-A-7-137790

  However, in the sloshing suppression device of Patent Document 1, the larger the external vibration due to an earthquake or the like given to the tank 103, the larger the scale of the inner chamber 102, which is equipment required for suppressing sloshing. That is, in the sloshing suppression device of Patent Document 1, the larger the assumed external vibration and the higher the importance of ensuring safety, the larger the equipment required for sloshing suppression, and the more efficient it is. In other words, the cost is much higher.

  Therefore, the present invention converts the energy of the flow due to sloshing of the storage liquid into energy that suppresses the flow of the storage liquid, so that the equipment can be made extremely large even when the external vibration assumed in the design is large. It is an object of the present invention to provide a method capable of suppressing sloshing without being performed and capable of suppressing sloshing with relatively simple maintenance.

  While examining and analyzing the structure for suppressing sloshing in the cooling water intake tank of the operating equipment, the present inventors formed a water channel corner in the water intake tank and extended the entire flow path to this water channel corner. It was found that sloshing can be effectively suppressed by generating multiple vortices.

The sloshing suppression method according to claim 1 is based on the above knowledge, and at least when a sloshing occurs, a horizontal plate that is in contact with or immersed in the liquid level of the storage liquid in the storage tank, and a side wall of the storage tank of the horizontal plate horizontally a plurality of rectangular obstacles which are arranged in the vertical direction Rutotomoni, as a frame member provided with a water channel angle forming portion and a vertical plate to the side walls facing in the reservoir together with the rise from the end of the side Two screens are provided between the horizontal plate and the bottom of the storage tank, with two screens facing each other perpendicular to the flow direction of the storage liquid between the plate and the bottom of the storage tank. The interval between the rectangular obstacles on one screen is twice the interval between the rectangular obstacles on the other screen, and the height of the upper surface of the rectangular obstacle on one screen and the height of the lower surface of the rectangular obstacle on the other screen The match, to suppress the flow of the stock solution in water channel corner by vortex with a vortex throughout is generated between the bottom of the reservoir and the horizontal plate in waterways corner of side wall end part side of the horizontal plate Thus, sloshing of the stored liquid in the storage tank is suppressed.

  Therefore, according to this sloshing suppression method, by providing a water channel corner forming portion having a horizontal plate and a vertical plate facing the side wall of the storage tank, when sloshing occurs in the stored liquid in the storage tank, the water channel corner section After the storage liquid once enters the space between the vertical plate of the forming unit and the side wall of the storage tank, it is about to flow from this space toward the space between the horizontal plate of the channel corner forming unit and the bottom of the storage tank. Since the vortex over the entire flow path is generated at the corner of the water channel when the vertical plate and the horizontal plate are circulated, the storage liquid at the corner of the water channel is generated by the vortex generated by the flow energy of the storage liquid in the storage tank. Is suppressed, and sloshing of the stored liquid in the storage tank is suppressed. In the present invention, the vortex used for suppressing the flow of the stored liquid is a kind of vortex called tumble or close to it.

  According to the sloshing suppression method of the present invention, the flow caused by the sloshing of the stored liquid in the storage tank is used to generate a vortex over the entire flow path at the corner of the water channel, and the flow of the stored liquid is suppressed by this vortex. When the liquid level fluctuation due to sloshing is large and the energy of the flow of the storage liquid is large, a vortex having a size and rotation speed commensurate with it is formed, and the flow of the storage liquid is strongly suppressed accordingly. Is possible. Therefore, by converting the energy of the flow of the storage liquid into energy for suppressing the flow of the storage liquid and consuming it without making the scale of the water channel corner forming portion, that is, the equipment for suppressing sloshing extremely large Sloshing can be effectively suppressed. Moreover, since sloshing can be suppressed with relatively simple equipment, the cost for suppressing sloshing can be reduced.

  Hereinafter, the configuration of the present invention will be described in detail based on the best mode shown in the drawings.

  1 to 3 show an example of an embodiment of the sloshing suppressing method of the present invention. In addition, in this embodiment, the water intake tank 1 for storing the water 4 which cools an operation | use equipment as a storage tank which is an object structure of the sloshing suppression of the liquid (namely, stored liquid) stored / stored inside (1) FIG. 1) is taken as an example. However, the structure that can be applied to the sloshing suppression method of the present invention is not limited to the water intake tank 1 of the present embodiment.

  The sloshing suppression method of the present invention includes a horizontal plate 3b that is in contact with or submerged in the stored water 4 in the water intake tank 1 at least when sloshing occurs, and an end of the horizontal plate 3b on the side wall 2a side of the water intake tank 1. A water channel corner forming part 3 having a vertical plate 3c that rises from the side and faces the side wall 2a is provided in the water tank 1, and the horizontal plate 3b is connected to the horizontal plate 3b at the water channel corner 2w below the side wall 2a end of the horizontal plate 3b. A vortex over the entire flow path between the bottom portion 2b of the water tank 1 is generated and the flow of the stored water 4 in the water channel corner portion 2w is suppressed by the vortex so as to suppress the sloshing of the stored water 4 in the water intake tank 1. I have to.

  As shown in FIG. 1, the water intake tank 1 of the present embodiment includes a bowl-shaped main body 2 having a rectangular cross section having side walls 2 a, 2 a ′ and a bottom portion 2 b, and an upper plate 3 a and a horizontal plate arranged horizontally. 3b and a vertical plate 3c that is vertically connected to these end portions and faces the side wall 2a, and has a water channel corner portion forming portion 3 having a U-shaped longitudinal section in the installed state. A water supply port (not shown) is provided on the side wall 2a 'opposite to the side wall 2a facing the vertical plate 3c.

  The reservoir 2c surrounded by the side walls 2a, 2a 'and the bottom 2b of the main body 2 of the intake tank 1 is composed of a sand basin 2x, a screen chamber 2y, and a pump chamber 2z, and in order from the side wall 2a' side where the water supply port is provided. A sand basin 2x, a screen chamber 2y, and a pump chamber 2z are arranged.

  In the present embodiment, seawater is specifically supplied to the sand basin 2x of the intake tank 1 as the stored water 4 from the water supply port provided on the side wall 2a '. Seawater, that is, stored water 4 supplied to the sand basin 2x passes through the screen chamber 2y and flows into the pump chamber 2z. And it pumps up with the pump (illustration omitted) with which the pump chamber 2z was equipped.

  In the present embodiment, in order to keep pumping up the stored water 4 from the pump chamber 2z by the pump and constantly supplying it to the operating equipment as cooling water, the intake port at the lower end of the pump provided in the pump chamber 2z of the water intake tank 1 is used. In the stored water 4 so as not to be exposed. That is, it is necessary that the water level in the pump chamber 2z does not fall below the intake limit water level that is the design lower limit water level due to sloshing.

  In the following, the direction of the stored water 4 between the sand basin 2x and the pump chamber 2z and parallel to the bottom 2b is simply referred to as the flow direction.

  A water channel corner forming portion 3 is provided in the screen chamber 2 y of the water intake tank 1. The water channel corner forming portion 3 is for forming the water channel corner portion 2w in the storage portion 2c.

  The vertical plate 3c of the water channel corner forming portion 3 is provided to face the side wall 2a on the pump chamber 2z side. Further, the upper plate 3a, the horizontal plate 3b, and the vertical plate 3c are fixed to the main body 2 of the water intake tank 1.

  As shown in FIGS. 1 and 2, the water storage tank 1 of the present embodiment further includes a screen 5 between the horizontal plate 3b and the bottom 2b of the screen chamber 2y. The screen 5 prevents dust and foreign matters mixed in the stored water 4 from flowing into the pump chamber 2z when the stored water 4 flows from the sand basin 2x to the pump chamber 2z. It consists of two screens, a screen 5a and a rear screen 5b on the pump chamber 2z side.

  Both the front screen 5a and the rear screen 5b are provided with their screen surfaces facing each other perpendicularly or substantially perpendicular to the flow direction of the stored water 4 from the sand basin 2x to the pump chamber 2z.

  On the front screen 5a and the rear screen 5b, a plurality of rectangular obstacles are arranged in the vertical direction as screen frame members.

  Specifically, as shown in FIG. 3, a rectangular obstacle 5a-f is arranged on the front screen 5a, and a rectangular obstacle 5b-f is arranged on the rear screen 5b. And in the parts other than the rectangular obstacles 5a-f and 5b-f, the stored water 4 can freely flow, while the rectangular obstacles 5a-f and 5b-f affect the flow of the stored water 4. To do.

  In the present embodiment, the distance between the rectangular obstacles 5a-f on the front screen is twice the distance between the rectangular obstacles 5b-f on the rear screen, and the two rectangular obstacles 5b-f on the rear screen 5b. One rectangular obstacle 5a-f on the front screen 5a corresponds. In the present embodiment, the two screens 5a and 5b are arranged such that the height of the upper surface of the rectangular obstacle 5a-f of the front screen 5a and the height of the lower surface of the rectangular obstacle 5b-f of the rear screen 5b coincide. The positional relationship is adjusted.

  According to the water tank 1 configured as described above, when sloshing occurs in the stored water 4 in the storage part 2c of the water tank 1, the vertical plate 3c and the main body of the water channel corner forming part 3 of the water tank 1 After the stored water 4 once enters the space between the two side walls 2a, the vertical plate tries to flow from this space toward the space between the horizontal plate 3b of the channel corner portion forming portion 3 and the bottom portion 2b of the main body 2. When going around 3c and the horizontal plate 3b, a vortex over the entire flow path can be generated at the water channel corner 2w. By generating this vortex, the flow of the stored water 4 from the space between the vertical plate 3c and the side wall 2a to the space between the horizontal plate 3b and the bottom 2b via the water channel corner 2w Since it can suppress in the part 2w, the sloshing of the stored water 4 in the storage part 2c can be suppressed by suppressing the water level fall of the pump chamber 2z.

  And this invention converts the energy of the flow by the sloshing of the stored water 4 into vortex energy by the above-mentioned mechanism and consumes it, and if the flow energy of the stored water 4 in the storage part 2c is large, the said flow energy Since the energy of the vortex formed at the corner 2w of the water channel is also increased by the conversion of the vortex, the larger the vibration energy from the outside and the greater the flow energy due to sloshing, the larger and faster the vortex is formed and the flow energy is consumed. In addition, the effect of suppressing the flow of the stored water 4 in the water channel corner 2w is also increased. That is, according to the present invention, the larger the sloshing, the more suitable vortex is formed, so the sloshing can be effectively suppressed.

In addition, although the above-mentioned form is an example of the suitable form of this invention, it is not limited to this, A various deformation | transformation implementation is possible in the range which does not deviate from the summary of this invention .

For example , in the present embodiment, the water channel corner forming portion 3 is configured as having the upper plate 3a, but the upper plate 3a is not essential and may be configured without the upper plate 3a. Absent.

  An example of the effect evaluation when the sloshing suppression method of the present invention is applied to a water tank will be described with reference to FIGS.

  In this example, a water intake tank having the same configuration as the water intake tank described in the above embodiment was modeled, and the two-dimensional flow analysis of the stored water in the storage part was performed to evaluate the sloshing suppression effect according to the present invention. .

  Specifically, first, a representative cross section of the water intake tank 1 was modeled as shown in FIGS.

  The storage part 2c of the main body 2 of the water storage tank 1 is a side wall provided with a water supply port, and stores the stored water 4 from the side wall 2a 'on the sedimentation basin 2x side to the side wall 2a on the pump chamber 2z side on the opposite side. The length in the flow direction is 102 m.

  Then, in order from the side wall 2a 'side where the water supply port is provided, the length of the sand basin 2x in the flow direction is 60m, the screen chamber 2y is 36m, and the pump chamber 2z is 6m. The height of the side wall 2a 'on the sand basin 2x side is 16.9m, and the height of the side wall 2a on the pump chamber 2z side is 17.4m. As a model of the intake tank 1 for two-dimensional flow analysis, it is assumed that the upper plate 3a extends to the side wall 2a on the pump chamber 2z side and the upper end of the pump chamber 2z is closed. Further, as a model of the water intake tank 1 for two-dimensional flow analysis, the side wall 2a 'is assumed to be an entire wall and no opening.

  Further, the distance between the vertical plate 3c of the water channel corner forming portion 3 and the side wall 2a on the pump chamber 2z side is 6 m.

  The height of the portion of the water channel corner forming portion 3 facing the side wall 2a on the pump chamber 2z side is 9.3 m, and the length of the portion facing the bottom portion 2b is 36 m. And the space | interval between the horizontal plate 3b and the bottom part 2b of the water channel corner | angular part formation part 3 is 7.9 m. The upper plate 3a, the horizontal plate 3b, and the vertical plate 3c of the water channel corner forming portion 3 are all 1.5 m thick.

  The front screen 5a is installed at a position 8m closer to the pump chamber 2z from the end of the horizontal plate 3b on the sand basin 2x side, and the rear screen 5b is further installed at a position 8m closer to the pump chamber 2z from the front screen 5a. That is, the rear screen 5b is provided at a position 20 m closer to the sand basin 2x from the end of the horizontal plate 3b of the water channel corner forming portion 3 on the pump chamber 2z side.

  As shown in FIG. 6, the cross section of the rectangular obstacles 5a-f and 5b-f has a height of a surface facing the flow direction of the stored water 4 of 0.24 m and a length in the flow direction of 1 m. . The distance between the rectangular obstacles 5a-f on the front screen 5a (that is, the distance from the center to the center of the adjacent rectangular obstacles 5a-f on the front screen 5a) is 1.44 m. Further, the interval between the rectangular obstacles 5b-f on the rear screen 5b is 0.72 m. The mutual positional relationship between the screens 5a and 5b is adjusted so that the height of the upper surface of the rectangular obstacle 5a-f on the front screen 5a and the height of the lower surface of the rectangular obstacle 5b-f on the rear screen 5b coincide. The

  The fluid analysis of the free liquid level was performed using the model of the intake tank 1 described above, and the time fluctuation of the water level in the pump chamber 2z due to sloshing in the intake tank 1 and the time fluctuation of the flow velocity distribution around the water channel corner 2w were grasped. In addition, SLOSH2D ("Nonlinear sloshing evaluation of a rectangular aquarium with overflow", Power Research Institute report: N06031, June 2007) was used for the two-dimensional flow analysis of a present Example.

  Moreover, the case where it was set as the application example 1 and the structure which does not provide the screen 5 about the water intake tank 1 with the water intake tank 1 mainly demonstrated by the above-mentioned embodiment as the application example 2, and evaluated the sloshing suppression effect about each. In addition, when it only describes with the intake tank 1 below, it shall refer to both the intake tank 1 which has the screen 5, and the intake tank 1 which does not have the screen 5. FIG.

  In this example, the flow analysis in the intake tank 1 was performed when the reference ground motion Ss (“Outline of Hamaoka Nuclear Power Station and Development of Standard Ground Motion Ss”, Chubu Electric Power Co., Inc., April 2007) was given. Since the sloshing period in the flow direction of the intake tank 1 was considered to be a long period region exceeding 10 seconds, in this example, the reference ground motion Ss-3H (virtual Tokai / Tonankai / Nankai) with a large acceleration in the region. The flow analysis was performed using (earthquake). FIG. 7 shows the acceleration time history of the reference ground motion Ss-3H. In FIG. 7, the vertical axis represents acceleration and the horizontal axis represents time.

  Here, it is considered that the liquid level fluctuation in the water intake tank 1 due to external vibration becomes larger when the horizontal movement in the long side direction is given than when the horizontal movement in the short side direction of the water intake tank 1 is given. Therefore, in this embodiment, it is assumed that horizontal movement in the flow direction that is the long side direction of the water intake tank 1 is given.

  In this embodiment, the water depth (hereinafter referred to as the reference water level) of the pump chamber 2z before applying vibration from the outside is 10.485 m (this corresponds to −3.415 m at the Tokyo Bay average sea surface TP). ).

  A two-dimensional flow analysis was performed for each of Application Example 1 and Application Example 2 using the above conditions, and the results shown in FIGS. 8 and 9 were obtained for the temporal fluctuation of the water level in the pump chamber 2z. 8 and 9, the vertical axis represents the water level, and the horizontal axis represents the elapsed time from the start of adding the reference ground motion Ss to the water intake tank 1. 8 and 9, the solid line represents the water level at the left end of the pump chamber 2z, the broken line represents the water level at the right end of the pump chamber 2z, and the alternate long and short dash line represents the change over time in the average water level in the pump chamber 2z.

  From FIG. 8 which shows the result of the application example 1 which concerns on the water intake tank 1 in which the front screen 5a and the rear screen 5b are provided in addition to the water channel corner forming part 3, the stored water 4 is separated from the side wall 2a by vibration from the outside. Once entering the space between the vertical plate 3c and the water level of the pump chamber 2z once rises about 8m from the reference water level, the water level drop of the pump chamber 2z due to the subsequent swing back is suppressed to about 1.5m from the reference water level. It was confirmed that the liquid level fluctuation can be settled in a short time.

  Moreover, from FIG. 9 which shows the result of the application example 2 which concerns on the water intake tank 1 in which the water channel corner | angular part formation part 3 is provided but the screen 5 is not provided, it is the vibration from the outside like the case of the application example 2. As a result, the water level in the pump chamber 2z rises about 8 m from the reference water level once, but the water level drop in the pump chamber 2z due to the subsequent swing back can be suppressed to about 4 m from the reference water level. It was confirmed that can be reduced to about half of the rise from the reference water level.

  Moreover, the result shown in FIGS. 10-12 about the time fluctuation of the flow velocity distribution around the water channel corner | angular part 2w was obtained. 10 to 12 are flow velocity distribution diagrams of longitudinal sections of the screen chamber 2y and the pump chamber 2z of the water intake tank 1. FIG. Also, in FIGS. 10 to 12, the shading in the figure represents the flow velocity at each point, and the closer to black, the faster the flow velocity at that point.

  Moreover, the result shown in FIG. 10 is the result of the flow velocity distribution when 48.4 seconds have elapsed from the start of the addition of the reference ground motion Ss, FIG. 11 is the result when 50.7 seconds have elapsed, and FIG. In this time zone, the stored water 4 has potential energy that can be lowered by swinging back after the water level in the pump chamber 2z has once increased greatly from the reference water level due to external vibration. This corresponds to the time zone you have.

  First, from FIG. 10 which is the result of the flow velocity distribution when the elapsed time from the start of the addition of the reference ground motion Ss is 48.4 seconds, a front screen 5a and a rear screen 5b are provided in addition to the water channel corner forming part 3. In the application example 1 related to the intake tank 1 (FIG. 10A), the elliptical shape of the stored water 4 has a size over almost the entire space between the horizontal plate 3b and the bottom 2b in the channel corner 2w. The flow vortex 4a is starting to be formed, and the flow of the stored water 4 from the space between the side wall 2a and the vertical plate 3c around the space channel corner 2w toward the screen chamber 2y is suppressed, and the channel angle of the screen chamber 2y. It was confirmed that the flow velocity of the stored water 4 on the sand settling basin 2x side is smaller than the part 2w.

  Moreover, in the application example 2 which concerns on the intake tank 1 in which the water channel corner | angular part formation part 3 is provided, but the screen 5 is not provided (FIG.10 (B)), vortex 4a is being formed in the water channel corner | angular part 2w. Although it can be seen, the shape is not yet clear as compared with Application Example 1, and storage from the space between the side wall 2a and the vertical plate 3c around the water channel corner 2w toward the screen chamber 2y. Since the flow of the water 4 was not sufficiently suppressed, the flow rate of the stored water 4 in the screen chamber 2y was not as small as that of the application example 1.

  Next, from FIG. 11 which is the result of the flow velocity distribution when the elapsed time from the start of the addition of the reference ground motion Ss is 50.7 seconds, the shapes of the application example 1 and the application example 2 are clearly recognized in the channel corner 2w. Two vortices 4a of the flow of stored water 4 are formed, and the flow of the stored water 4 from the space between the side wall 2a and the vertical plate 3c around the water channel corner 2w toward the screen chamber 2y is shown in FIG. It was confirmed that the flow rate of the stored water 4 in the screen chamber 2y was further reduced compared to the time when 48.4 seconds passed, which was shown.

  And in the application example 2, the lowering of the water level in the pump chamber 2z is suppressed by the action of the vortex 4a. Further, in the application example 1, the action of the vortex 4a is stronger than the application example 2, and the flow of the stored water 4 is more Since it was strongly suppressed, it was confirmed that the drop in the water level from the reference water level in the pump chamber 2z was slight compared to Application Example 2.

  Furthermore, from FIG. 12, which is the result of the flow velocity distribution when the elapsed time from the start of addition of the reference seismic motion Ss is 51.5 seconds, both the application example 1 and the application example 2 show the flow of the stored water 4 in the channel corner 2w. It was confirmed that two vortices 4a remained and the flow of the stored water 4 from the space between the side wall 2a and the vertical plate 3c around the water channel corner 2w toward the screen chamber 2y was suppressed.

  And at this time, it was confirmed that the suppression force of the water level fall of the pump chamber 2z by the flow suppression force of the vortex 4a in the application example 1 worked strongly.

  In order to compare with the above-mentioned application examples 1 and 2, a comparative example was set, and the same analysis was performed for the comparative example.

  In Application Examples 1 and 2, as shown in FIG. 6, the height of the upper surface of the rectangular obstacle 5a-f on the front screen 5a and the height of the lower surface of the rectangular obstacle 5b-f on the rear screen 5b are matched. The mutual positional relationship between the screens 5a and 5b is adjusted. On the other hand, in the comparative example, as shown in FIG. 13, both screens are such that the height of the upper surface of the rectangular obstacles 5a-f on the front screen 5a is the center of the rectangular obstacles 5b-f on the rear screen 5b. The mutual positional relationship between 5a and 5b was adjusted. Other conditions were the same in Application Examples 1 and 2 and Comparative Example.

  A two-dimensional flow analysis was performed for the comparative example, and the results shown in FIG. 14 were obtained for the time fluctuation of the water level in the pump chamber 2z. The display method and contents of FIG. 14 are the same as those of FIG.

  From the results shown in FIG. 14, in the case of the comparative example, the stored water 4 once enters the space between the side wall 2a and the vertical plate 3c due to external vibration, and the water level of the pump chamber 2z is about 8 m from the reference water level. It was confirmed that the rocking after the rising lowered by 5 m from the reference water level, and the subsequent liquid level fluctuation also took a long time to settle down as compared with Application Examples 1 and 2.

  Moreover, the result shown in FIG. 15 was obtained about the time fluctuation of the flow velocity distribution around the channel corner 2w when 51.5 seconds have elapsed since the start of the addition of the reference ground motion Ss. The display method and contents of FIG. 15 are the same as those of FIG.

  From the results shown in FIG. 15, in the case of the comparative example, a vortex that can clearly recognize the shape is not formed in the channel corner portion 2W, and the channel angle is determined from the space between the side wall 2a and the vertical plate 3c. It has been confirmed that the flow rate of the stored water 4 in the screen chamber 2y remains large because the flow of the stored water 4 that goes around the portion 2w toward the screen chamber 2y is not suppressed.

  From the above results, by providing at least the water channel corner forming part 3 in the water intake tank 1, the vortex 4a is formed in the water channel corner 2w below the horizontal plate 3b of the water channel corner forming part 3 and the water inside the water intake tank 1 It was confirmed that when the sloshing of the stored water 4 occurs, the flow of the stored water 4 can be suppressed by the vortex 4a, and the sloshing in the water tank 1 can be suppressed.

  In addition, the front screen 5a and the rear screen 5b are provided between the horizontal plate 3b and the bottom portion 2b so as to adjust the positions of each other, thereby forming a vortex 4a that is faster in rotation and making the flow of the stored water 4 stronger. It was confirmed that sloshing in the water storage tank 1 can be suppressed more strongly.

It is a longitudinal cross-sectional view which shows the water intake tank of embodiment. It is an enlarged vertical sectional view of a screen chamber and a pump chamber portion of the water intake tank of the embodiment. It is a longitudinal cross-sectional view explaining the structure and arrangement | positioning of the screen of the water intake tank of embodiment. It is a longitudinal cross-sectional view which shows the water intake tank of the application examples 1 and 2 of Example 1. FIG. FIG. 3 is an enlarged vertical sectional view of a screen chamber and a pump chamber portion of the water intake tank of Application Examples 1 and 2 of Example 1. It is a longitudinal cross-sectional view explaining the structure and arrangement | positioning of the screen of the water intake tank of the application examples 1 and 2 of Example 1. FIG. It is a figure which shows the acceleration time history of the standard ground motion Ss-3H of Example 1. FIG. It is a figure which shows the time fluctuation of the water level of the pump chamber of the application example 1 of Example 1. FIG. It is a figure which shows the time fluctuation of the water level of the pump chamber of the application example 2 of Example 1. FIG. It is a figure which shows the flow-velocity distribution of a screen chamber and a pump chamber at the time of 48.4 second progress from the reference | standard ground motion addition start of Example 1. FIG. (A) is a figure which shows the flow-velocity distribution of the application example 1. FIG. (B) is a figure which shows the flow-velocity distribution of the application example 2. FIG. It is a figure which shows the flow-velocity distribution of the screen chamber at the time of 50.7 second progress from the start of addition of the reference ground motion of Example 1, and a pump chamber. (A) is a figure which shows the flow-velocity distribution of the application example 1. FIG. (B) is a figure which shows the flow-velocity distribution of the application example 2. FIG. It is a figure which shows the flow-velocity distribution of the screen chamber at the time of 51.5 second progress from the start of addition of the reference ground motion of Example 1, and a pump chamber. (A) is a figure which shows the flow-velocity distribution of the application example 1. FIG. (B) is a figure which shows the flow-velocity distribution of the application example 2. FIG. It is a longitudinal cross-sectional view explaining the structure and arrangement | positioning of the screen of the intake tank of the comparative example of Example 1. FIG. It is a figure which shows the time fluctuation of the water level of the pump chamber of the comparative example of Example 1. FIG. It is a figure which shows the flow-velocity distribution of a screen chamber and a pump chamber at the time of 51.5 second progress from the reference | standard ground motion addition start of the comparative example of Example 1. FIG. It is a longitudinal cross-sectional view which shows the conventional sloshing suppression apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Water intake tank 2 Water intake tank main body 2a Side wall 2b Bottom part 2c Storage part 2w Water channel corner part 3 Water channel corner part formation part 3a Upper plate 3b Horizontal plate 3c Vertical plate 4 Reserved water 5 Screen 5a Front screen 5b Rear screen

Claims (1)

A horizontal plate that is in contact with or submerged in the storage liquid in the storage tank at least when sloshing occurs, and a vertical plate that rises from an end of the horizontal plate on the side of the storage tank and faces the side wall. said storage between the bottom of the channel corners Rutotomoni provided forming section to the storage tank, the horizontal plate and the reservoir has a plurality of rectangular obstacles which are arranged in the vertical direction frame member having Two rectangular screens facing each other perpendicular to the liquid flow direction are provided between the horizontal plate and the bottom of the storage tank, and the rectangular obstacle on one of the two screens. The distance between the rectangular obstacles on the other screen is twice as long as the other, and the height of the upper surface of the rectangular obstacle on the one screen and the height of the lower surface of the rectangular obstacle on the other screen Match, the storage liquid in the coolant channel corner by vortex with a vortex throughout is generated between the bottom of the reservoir and the horizontal plate in waterways corner of the side wall end part side of said horizontal plate The sloshing suppression method characterized by suppressing the sloshing of the said stored liquid in the said storage tank by suppressing the flow of this.