CN108025800B

CN108025800B - Offshore structure comprising flow attenuating structure

Info

Publication number: CN108025800B
Application number: CN201680053603.5A
Authority: CN
Inventors: 梁胜皓
Original assignee: Samsung Heavy Industries Co Ltd
Current assignee: Samsung Heavy Industries Co Ltd
Priority date: 2015-09-15
Filing date: 2016-09-13
Publication date: 2020-06-23
Anticipated expiration: 2036-09-13
Also published as: KR20170032548A; SG11201801972TA; KR101762700B1; WO2017048055A1; CN108025800A

Abstract

The present invention provides an offshore structure comprising a flow attenuating structure. The offshore structure comprises: a hull formed with a moon pool; and a flow attenuating structure attenuating a flow inside the moon pool, wherein the flow attenuating structure includes a first attenuating member formed to protrude from a bottom of the offshore structure to the interior of the moon pool, and dividing the interior of the moon pool into a first space and a second space.

Description

Offshore structure comprising flow attenuating structure

Technical Field

The present invention relates to an offshore structure including a flow attenuating structure, and more particularly, to an offshore structure including a flow attenuating structure, which prevents seawater flowing into the offshore structure from overflowing to a deck, and reduces resistance applied to the operation of the offshore structure due to a moon pool during operation of the offshore structure.

Background

In general, a drill ship is used as a facility for extracting crude oil, gas, or the like from the sea, and enables extraction work of crude oil, gas, or the like in a deep sea area where an offshore platform cannot be installed or in an offshore area with large waves.

The drilling vessel is centrally formed with a MOON POOL (MOON POOL) configured as an opening for placing a pipe for drilling on the bottom surface of the sea floor. And, a means for drilling is provided at a moonpool perimeter DECK (DECK).

However, since seawater flows into the moon pool, resistance is applied to the ship during operation, and this structure is very disadvantageous in terms of the stability and performance of the ship.

When the frequency of the seawater flowing into the moon pool matches the frequency of the seawater inside the moon pool, the seawater resonates in the moon pool and overflows to the deck. Therefore, the devices installed at the peripheral deck of the moon pool may be broken or damaged due to the impact pressure of seawater.

In order to solve the above problems, a conventional document (korean registered patent No. 10-1259718) prevents the flow of seawater from flowing into the interior of the moon pool due to the formation of the flow of seawater at the lower portion of the block, and includes a control deck for suppressing the flow of seawater flowing into the moon pool, thereby reducing the resistance caused by the moon pool.

However, in the conventional document, the seawater flowing during the operation of the drill ship can be prevented from flowing into the moon pool, but the effect of suppressing the seawater flowing into the moon pool by the waves is not so great in the state where the drill ship is stationary.

Therefore, an apparatus capable of preventing seawater flowing into the moon pool from overflowing to the deck is required.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide an offshore structure including a flow attenuating structure, which can prevent seawater flowing into a moon pool from overflowing to a deck of the offshore structure.

The technical problems of the present application are not limited to the above-mentioned problems, and other technical problems not mentioned can be clearly understood by a person of ordinary skill from the following description.

In order to solve the problems, an offshore structure according to an embodiment of the present invention includes: a hull formed with a moon pool; and a flow attenuating structure attenuating a flow inside the moon pool, wherein the flow attenuating structure includes a first attenuating member formed to protrude from a bottom of the offshore structure to the interior of the moon pool and dividing the interior of the moon pool into a first space and a second space.

The first space is formed on a stern side of the offshore structure, the second space is formed on a bow side of the offshore structure, and a length of the second space is longer than a length of the first space.

The first damping member is lower than the moon pool in height, and a cancellation space for canceling seawater flowing in from the first space and the second space is formed above the first damping member.

One surface of the first attenuation part connected with the first space is formed in an inclined mode, and the other surface of the first attenuation part connected with the second space is parallel to the inner side face of the moon pool.

The closer the one surface of the first attenuation member is to the other surface, the closer the one surface is from the upper surface toward the bottom surface.

Further comprising: a guide member formed to protrude from a deck of the offshore structure to an inside of the moon pool, and guiding a flow direction of seawater to flow the seawater flown into the first space to the offset space.

The guide member is formed to be inclined upward as it goes from the inner side surface of the moon pool toward the end of the moon pool.

Further comprising: and a second damping member formed to protrude from a bottom of the offshore structure to an inside of the moonpool, and formed to be spaced apart from the first damping member, and dividing the second space into a first partial space and a second partial space.

The first partial space is disposed between the first space and the second partial space, and a length of the first partial space is longer than a length of the second space and longer than a length of the second partial space.

The flow attenuating structure further comprises: a rear inclined plate disposed above the first damping member and inclined downward toward the front; and a front inclined plate disposed above the second damping member and inclined rearward and downward.

Further comprising: a rear guide plate provided between a water surface inside the moon pool and the first damping member and protruding forward from a rear side wall of the moon pool; and a front guide plate which is provided between the water surface inside the moon pool and the second damping member and protrudes rearward from a front side wall of the moon pool.

Further comprising: and an inclined block disposed at a front side portion of the first damping member and having a front end surface inclined upward toward the front inclined plate.

The flow attenuating structure further comprises: a front inclined plate disposed above the second damping member and inclined rearward; a front guide plate provided between a water surface inside the moon pool and the second damping member and protruding rearward from a front side wall of the moon pool; a rear guide plate provided between a water surface inside the moon pool and the first damping member and protruding forward from a rear side wall of the moon pool; and the blocking plate is arranged between the water surface in the moon pool and the rear guide plate and is protruded from the rear side wall of the moon pool.

In order to solve the problem, an offshore structure according to another embodiment of the present invention includes: a hull formed with a moon pool; and a flow attenuating structure attenuating a flow inside the moon pool, wherein the flow attenuating structure further comprises: a first damping member and a second damping member which are arranged to be spaced apart from each other; a front inclined plate disposed above the second damping member and inclined rearward and downward; a first stopper plate provided between a water surface inside the moon pool and the first damping member and protruding forward from a rear side wall of the moon pool; and a second barrier plate provided on a water surface inside the moon pool and protruding forward from a rear side wall of the moon pool, wherein the second damping member is disposed in contact with the front side wall of the moon pool facing the second damping member, and the first damping member is disposed in contact with the rear side wall of the moon pool facing the first damping member.

In the offshore structure including the flow attenuating structure according to the embodiments of the present invention, the open space of the moon pool is divided into a plurality of spaces by the first attenuating member combined with the moon pool, and seawater introduced into the plurality of spaces can be offset from each other in the moon pool.

Therefore, the seawater flowing into the moon pool is prevented from overflowing to the deck of the offshore structure, thereby preventing the equipment disposed around the moon pool from being broken down by the impact pressure of the seawater.

In addition, during the operation of the offshore structure, the resistance applied to the offshore structure by the moon pool is reduced, thereby improving the operation efficiency of the offshore structure.

The effects of the embodiments of the present invention are not limited to the effects described above, and those skilled in the art can clearly understand other effects that are not described from the description of the scope of the claims.

Drawings

FIG. 1 is a diagram showing an offshore structure having a flow attenuating structure according to one embodiment of the present invention;

FIG. 2 is an enlarged perspective view of the flow attenuating structure of FIG. 1;

FIG. 3 is a cross-sectional view of the flow attenuating structure of FIG. 1;

FIG. 4 is a graph showing the size of the flow attenuating structure of FIG. 1;

FIG. 5 is a graph showing the height of waves within a moon pool of an offshore structure having a flow attenuating structure according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of an offshore structure showing another embodiment of the invention;

FIG. 7 is a diagram showing a guide member of an offshore structure according to another embodiment of the invention;

FIG. 8 is a diagram schematically illustrating a portion of an offshore structure in accordance with yet another embodiment of the present invention;

fig. 9 is a diagram showing an experimental example of the flow attenuating structure of fig. 8;

FIG. 10 is a view showing the comparative example of FIG. 9;

FIG. 11 is a diagram showing an offshore structure according to yet another embodiment of the invention;

fig. 12 is a diagram showing an experimental example of the flow attenuating structure of fig. 11;

FIG. 13 is a diagram showing an offshore structure according to yet another embodiment of the invention;

fig. 14 is a diagram showing an experimental example of the flow attenuating structure of fig. 13.

Detailed Description

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. The drawings are only for the purpose of more easily disclosing the contents of the present invention, and the scope of the present invention is not limited by the scope of the drawings, which can be more easily understood by those skilled in the art.

In the description of the embodiments of the present invention, it is noted that the components having the same functions are substantially completely different from those of the conventional apparatuses by using the same names and the same reference numerals.

The terms used in the present application are used only for describing specific embodiments, and do not limit the present invention. The term "a" or "an" is used herein to describe a term that is not a singular or singular term. The terms "comprises" or "comprising" in the present application mean the presence or addition of any feature, number, step, action, component, element, component, or combination of features, number, step, action, component, or combination of components described in the specification, and it is to be understood that the presence or addition of one or more other features, number, step, action, component, or feature, number, step, action, component, or combination of components is not excluded.

Fig. 1 is an offshore structure having a flow attenuating structure according to an embodiment of the present invention, and fig. 2 is an enlarged perspective view of the flow attenuating structure of fig. 1.

Referring to fig. 1 and 2, a moon pool 100 penetrates the offshore structure 50. Various equipments for drilling are provided at a peripheral deck (deck) of the moon pool 100, and pipes for drilling and the like extend through the moon pool 100 to the seabed.

As shown in fig. 1 and 2, an offshore structure having a flow attenuating structure according to an embodiment of the present invention includes a first attenuating element 200.

The first damping member 200 is installed in the moon pool 100 penetrating the offshore structure 50, and protrudes from the bottom of the offshore structure 50 into the moon pool 100 to divide the interior of the moon pool 100 into the first space 110 and the second space 120.

Seawater flows from the bottom surface of the offshore structure 50 into the open space of the moon pool 100. Thereby, the seawater flows from the bottom surface 80 of the offshore structure 50 into the first space 110 and the second space 120 of the moon pool 100, respectively.

At this time, the first space 110 is formed on the stern 70 side of the offshore structure 50, and the second space 120 is formed on the bow 60 side of the offshore structure 50.

When the offshore structure 50 moves, the seawater flowing along the bottom surface 80 of the offshore structure 50 flows from the bow 60 of the offshore structure 50 toward the stern 70. Therefore, the first attenuating member 200 is combined with the moon pool 100 in such a manner as to cross the flow direction of the seawater.

Therefore, when the offshore structure 50 moves, the seawater flowing into the second space 120 and the first space 110 from the bottom 80 of the offshore structure 50 flows in the moon pool 100 from the bow 60 of the offshore structure 50 toward the stern 70.

In addition, when drilling work is performed while the offshore structure 50 is stationary, seawater flows into the first space 110 and the second space 120 due to waves.

The first damping member 200 is lower than the moon pool 100, and a canceling space 130 for canceling seawater flowing in from the first space 110 and the second space 120 is formed above the first damping member 200.

That is, in an embodiment of the present invention, the first attenuating member 200 is formed such that the seawater flowing into the first space 110 and the seawater flowing into the second space 120 cancel each other in the canceling space 130.

To this end, as shown in fig. 3, one surface 230 of the first attenuating member 200 connected to the first space 110 is formed to be inclined, and the other surface 240 of the first attenuating member 200 connected to the second space 120 is formed to be parallel to the inner side of the moon pool 100.

The flow directions of the seawater flowing into the first space 110 along one surface 230 of the first damping member 200 and the seawater flowing into the second space 120 along the other surface 240 are different from each other.

In this case, the inclined surface 230 of the first damping member 200 is closer to the other surface 240 as it goes from the upper surface 210 to the bottom surface 220. Accordingly, the seawater flowing into the first space 110 moves toward the inner surface of the moon pool 100 along the one surface 230 of the first damping member 200, and then flows toward the offset space 130 after coming into contact with the inner surface of the moon pool 100.

In addition, the seawater flowing into the second space 120 along the other surface 240 of the first damping member 200 flows from the second space 120 to the offset space 130.

The seawater flowing into the first space 110 and the seawater flowing into the second space 120 flow into the offset space 130 from different directions to offset each other in the offset space 130, and thus the seawater does not overflow to the peripheral deck D of the moon pool 100.

This prevents damage to equipment installed on the deck D due to the impact pressure of seawater.

In addition, in an embodiment of the present invention, since seawater flowing into the moon pool 100 is offset by the offset space 130, the operational resistance applied to the offshore structure 50 by the moon pool 100 is reduced, thereby improving the operational efficiency of the offshore structure 50.

As shown in fig. 4, the height and length of the first attenuating member 200 may vary depending on the equipment provided on the offshore structure 50 or the size of the offshore structure 50.

That is, various equipments are installed on the upper portion of the first damping member 200 according to the work performed in the moon pool 100.

Therefore, the first space 110 is formed smaller than the second space 120, and the first damping member 200 is close to the inner surface of the moon pool 100 forming the first space 110, whereby equipment can be easily installed on the upper portion of the first damping member 200.

And, the second space 120 is formed largely, whereby a riser or the like for drilling through the second space 120 is extended to the seabed.

For example, the height h2 of the first damping member 200 may be in the range of 20% to 80% of the height h1 of the moon pool, and the length L1 from the inner side surface of the moon pool 100 to the one surface 230 of the first damping member 200 may be in the range of 30% to 70% of the length L2 from the inner side surface of the moon pool 100 to the other surface 240 of the first damping member 200.

Therefore, the first damping member 200 is formed to have a length obtained by subtracting a length L1 from the inner surface of the moon pool 100 to the first surface 230 of the first damping member 200 from a length L2 from the inner surface of the moon pool 100 to the second surface 240 of the first damping member 200.

At this time, the length L2 from the inner side surface of the moon pool 100 to the other surface 240 of the first damping member 200 accounts for 20% to 80% of the length L of the moon pool 100.

In addition, as described above, one surface 230 of the first attenuating member 200 is formed to be inclined to guide the moving path of the seawater. Accordingly, as shown in fig. 4, the inclination angle θ 1 of the one face 230 of the first damping member 200 with respect to the upper face 210 of the first damping member 200 may be in the range of 30 degrees to 90 degrees.

That is, the first attenuating member 200 can be adjusted in size according to the size of the offshore structure 50 or the size of the moon pool 100 and the drilling equipment used.

Fig. 5 is a graph showing the height of waves in the moon pool of a ship having a flow attenuating structure according to an embodiment of the present invention. In fig. 5, the offshore structure 50 without the first attenuation member 200 in the moon pool 100 is illustrated in comparison to the offshore structure 50 with the first attenuation member 200 in the moon pool 100.

That is, as shown in fig. 3 to 5, assuming that the height of the deck is 6m, seawater flows into the moon pool 100 to resonate at a specific frequency, thereby overflowing onto the deck D, and seawater of a maximum height h1 of 2m can overflow from the moon pool 100 having the first attenuating member 200 to the deck D.

And the height h2 of the seawater overflowing from the moon pool 100 having the first attenuating member 200 to the deck D of the offshore structure 50 is 0m, so the seawater does not overflow to the deck D.

Accordingly, in the flow attenuating structure according to an embodiment of the present invention, since the moon pool 100 includes the first attenuating member 200, it is possible to prevent seawater flowing into the moon pool 100 from overflowing to the deck D, and thus it is possible to prevent equipment provided on the deck D around the moon pool 100 from being broken down due to the impact pressure of the seawater.

Fig. 6 is a cross-sectional view of an offshore structure showing another embodiment of the invention.

As shown in fig. 6, the flow attenuating structure includes a moon pool 100 and a first attenuating member 200.

The moon pool 100 and the first damping member 200 of the flow damping structure according to another embodiment of the present invention are the same as or substantially similar to the moon pool 100 and the first damping member 200 of the flow damping structure according to one embodiment of the present invention described above with reference to fig. 1 to 4, and thus, detailed description thereof is omitted.

In addition, as shown in the fig. 6 illustration, the flow attenuating structure further includes a guide member 300.

The guide member 300 is protrudingly formed from the deck D of the offshore structure 50 to the inside of the moon pool 100, and guides a flow direction of the seawater so that the seawater flowing into the first space 110 flows to the offset space 130.

That is, the seawater flowing into the first space 110 along the first damping member 200 flows to the offset space 130 along the guide member 300.

The guide member 300 is formed to be inclined upward from the inner side surface of the moon pool 100 toward the end of the moon pool 100.

Fig. 7 is a diagram showing a guide member of an offshore structure according to another embodiment of the present invention.

As shown in fig. 7, the bottom surface 300a of the guide member 300 and the horizontal surface of the deck D form an inclination angle θ 2 of 70 degrees or less.

As shown in fig. 6, the seawater flowing into the first space 110 flows along the first surface 230 of the first damping member 200 to the inner side surface of the moon pool 100, and then flows along the bottom surface 300a of the guide member 300 to the offset space 130 after contacting the inner side surface of the moon pool 100.

The seawater flowing into the offset space 130 along the guide member 300 meets and offsets the seawater flowing into the offset space 130 from the second space 120.

Thus, in the offshore structure of several embodiments of the present invention, the flow attenuating structure includes a first attenuating element 200. The seawater in the offsetting spaces 130 in the moon pool 100 offset each other by guiding the flow direction of the seawater flowing into the moon pool 100.

Seawater is prevented from overflowing from the moon pool 100 to the deck D, and thus, it is possible to prevent equipment installed on the deck around the moon pool 100 from being damaged by the impact pressure of the seawater.

Further, when the offshore structure 50 moves, the moon pool 100 can reduce resistance to the operation of the offshore structure 50.

Fig. 8 is a diagram schematically illustrating a portion of an offshore structure according to yet another embodiment of the present invention. For reference, when viewing fig. 8, the right direction is the front (bow side) of the offshore structure (e.g., drill ship) 1001, and the left direction is the rear (stern side) of the offshore structure 1001.

Referring to fig. 8, an offshore structure 1001 includes a hull 1010 and a flow attenuating structure 1100.

A moon pool 1020 is formed in the hull 1010. The moon pool 1020 is formed as an opening portion for lowering a drilling pipe (not shown) to the lower surface of the hull 1010, and the moon pool 1020 penetrates the hull 1010 in the vertical direction.

The flow attenuating structure 1100 attenuates flow within the moon pool 1020.

The flow attenuating structure 1100 includes a second attenuating member 1110 and a first attenuating member 1120. The second attenuating member 1110 is located below the water surface inside the moon pool 1020 and is disposed at the front (i.e., bow side) inside the moon pool 1020. The first damping member 1120 is located below the water surface inside the moon pool 1020 and is disposed at the rear (i.e., the stern side) inside the moon pool 1020.

The second damping member 1110 and the first damping member 1120 effectively damp the up-and-down movement of the water inside the moon pool 1020. In other words, the second and first damping

members

1110 and 1120 damp the up-and-down movement of the water by converting a part of the up-and-down movement energy of the water inside the moon pool 1020 into the horizontal movement energy.

The second damping member 1110 and the first damping member 1120 are spaced apart from each other, and a space (hereinafter, referred to as a first partial space 1031) between the second damping member 1110 and the first damping member 1120 allows the drilling pipe to move downward.

According to the present embodiment, the second damping member 1110 is disposed to be spaced apart from the front side wall of the moon pool 1020 opposite to the second damping member 1110. The first damping member 1120 is disposed to be spaced apart from a rear side wall of the moon pool 1020 facing the first damping member 1120. At this time, a space (hereinafter, referred to as a second partial space 1032) is formed between the second damping member 1110 and the front side wall of the moon pool 1020, and a space (hereinafter, referred to as a first space 1033) is formed between the first damping member 1120 and the rear side wall.

In this case, the vertical movement of the water flowing into the moon pool 1020 through the first partial space 1031, the second partial space 1032 and the first space 1033 is converted into a horizontal movement by the second damping member 1110 and the first damping member 1120, and in the process, the horizontal movements of the water are overlapped with each other and damped.

The flow attenuating structure 1100 also includes a front angled panel 1130 and a rear angled panel 1140. The front inclined plate 1130 is disposed above the second damping member 1110 and inclined downward toward the rear. The rear inclined plate 1140 is disposed above the first damping member 1120 and inclined downward toward the front. The front and rear

inclined plates

1130 and 1140 attenuate water waves inside the moon pool 1020.

Additionally, the flow attenuating structure 1100 also includes a front guide plate 1150 and a rear guide plate 1160.

The front guide 1150 is disposed between the water surface inside the moon pool 1020 and the second damping member 1110, and protrudes rearward from the front side wall of the moon pool 1020. The rear guide 1160 is disposed between the water surface inside the moon pool 1020 and the first damping member 1120, and protrudes forward from the rear side wall of the moon pool 1020.

The front guide plate 1150 and the rear guide plate 1160 guide water rising through the second partial space 1032 and the first space 1033 in a horizontal direction. This attenuates the upward and downward movement of water in the moon pool 1020.

Also, the flow attenuating structure 1100 further includes a tilt block 1170. The inclined block 1170 is disposed on the front side of the first damping member 1120, and has a front end surface inclined upward toward the front inclined plate 1130.

The tilt block 1170 switches the direction of the water flowing into the moon pool 1020 by the front tilt plate 1130, and the water waves generated during the switching of the direction are removed by the front tilt plate 1130.

Fig. 9 is a diagram showing an experimental example of the flow attenuating structure of fig. 8, and fig. 10 is a diagram showing a comparative example of the experimental example of fig. 9.

For reference, in fig. 9 and 10, the horizontal axis shows the frequency of the up-and-down movement of water inside the moon pool, and the vertical axis shows the height of the water surface at the central portion inside the moon pool. Also, the comparative example of fig. 10 shows the case where the interior of the moon pool is evacuated. The results of the experimental examples of fig. 9 and 10 are obtained by model experiments, but are not limited thereto.

Referring to fig. 10, in the comparative example in which the interior of the moon pool was evacuated, the up-and-down movement of the interior of the moon pool was confirmed to be strong between about 0.1 to 0.12 Hz.

On the other hand, referring to fig. 9, in the experimental example in which the flow attenuating structure 1100 according to the present example was provided inside the moon pool 1020, unlike fig. 10, it was confirmed that the vertical movement inside the moon pool 1020 was weak over the entire range of the frequency.

Fig. 11 is a diagram showing a flow attenuating structure according to yet another embodiment of the present invention. Referring to fig. 11, the flow attenuating structure 1200 includes a second attenuating member 1210, a first attenuating member 1220, a front inclined plate 1230, a front guide 1250, a rear guide 1260 and a blocking plate 1270.

The second damping member 1210, the first damping member 1220, the front inclined plate 1230, the front guide 1250, and the rear guide 1260 are the same as the second damping member 1110, the first damping member 1120, the front inclined plate 1130, the front guide 1150, and the rear guide 1160 of the above-described embodiments, and descriptions thereof are omitted.

Barrier 1270 serves to attenuate water waves inside moonpool 1020.

Fig. 12 is a diagram showing an experimental example of the flow attenuating structure of fig. 11. The comparative example of the experimental example of fig. 12 is the same as fig. 10.

Referring to fig. 11 and 12, in the experimental example in which the flow attenuating structure 1200 of the present example was provided inside the moon pool 1020, unlike fig. 10, it was confirmed that the vertical movement inside the moon pool 1020 was weak in the entire frequency range.

Fig. 13 is a diagram showing a flow attenuating structure according to yet another embodiment of the present invention. Referring to fig. 13, the flow attenuating structure 1300 includes a second attenuating member 1310, a first attenuating member 1320, a front inclined plate 1330, a first blocking plate 1371, and a second blocking plate 1372.

The second damping member 1310 is disposed in contact with a front side wall of the moon pool 1020 opposite to the second damping member 1310. The first damping member 1320 is disposed in contact with a rear side wall of the moon pool 1020 facing the first damping member 1320. In this case, the second partial space 1032 and the first space 1033 in fig. 8 disappear.

The front inclined plate 1330 is disposed above the second damping member 1310 and inclined downward toward the rear. The front inclined plate 1330 attenuates water waves inside the moon pool 1020.

The first blocking plate 1371 is disposed between the water surface inside the moon pool 1020 and the first attenuating member 1320, and protrudes forward from the rear side wall of the moon pool 1020. The first barrier 1371 prevents the interior of the moon pool 1020 from shaking.

The second blocking plate 1372 is provided on the water surface inside the moon pool 1020 and protrudes forward from the rear side wall of the moon pool 1020. The second barrier 1372 prevents the interior of the moon pool 1020 from shaking.

Fig. 14 is a diagram showing an experimental example of the flow attenuating structure of fig. 13. The comparative example of the experimental example of fig. 14 is the same as fig. 10.

Referring to fig. 13 and 14, in the experimental example in which the flow attenuating structure 1300 of the present example was provided inside the moon pool 1020, unlike fig. 10, it was confirmed that the vertical movement inside the moon pool 1020 was weak over the entire frequency range.

In summary, embodiments of the present invention have been studied, and it should be understood by those skilled in the art that embodiments other than the above-described embodiments can be embodied in other specific forms without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the above description, and can be modified within the scope of the claims and the equivalent scope, since the above embodiments are only examples.

Description of the reference numerals

50: the offshore structure 60: ship bow

70: stern 80: bottom surface of offshore structure

100: the moon pool 110: the first space

120: second space 130: offset space

200: first damping member 210: thereon is provided with

220: bottom surface 230: one side of

240: the other side 300: guide member

300 a: bottom surface D of guide member: deck board

H1: height H2 when the first damping member is not present: height in the presence of the first attenuating element

h 1: height h2 of moon pool: height of the first attenuating element

L: length of moon pool L1: to one face of the first attenuating element

L2: length θ 1 to the other surface of the first damping member: inclination angle of the first damping member

θ 2: angle of inclination of guide member

1001: offshore structure 1010: boat hull

1020: moon pool 1100: flow attenuating structures

1110: second damping member 1120: first damping part

1130: front inclined plate 1140: rear inclined plate

1150: front guide plate

1160: rear guide plate

1170: inclined block

Claims

1. An offshore structure, comprising:

a hull formed with a moon pool; and

a flow attenuating structure attenuating the flow inside the moon pool,

the flow attenuating structure includes:

a first attenuating member formed to protrude from a bottom of the offshore structure into the moonpool interior, and dividing the moonpool interior into a first space and a second space;

a second attenuating member formed to protrude from a bottom of the offshore structure to an inside of the moonpool and to be spaced apart from the first attenuating member, wherein the second attenuating member divides the second space into a first partial space and a second partial space; and

a front inclined plate disposed above the second damping member and inclined rearward and downward,

wherein at least a portion of the front inclined plate overlaps the second attenuating member.

2. Offshore structure according to claim 1,

the first space is formed at a stern side of the offshore structure, the second space is formed at a bow side of the offshore structure,

the length of the second space is longer than the length of the first space.

3. Offshore structure according to claim 1,

4. Offshore structure according to claim 1,

5. Offshore structure according to claim 4,

6. The offshore structure of claim 3, further comprising:

a guide member formed to protrude from a deck of the offshore structure to an inside of the moon pool, and guiding a flow direction of the seawater to flow the seawater flown into the first space to the offset space.

7. Offshore structure according to claim 6,

8. Offshore structure according to claim 1,

the first partial space is arranged between the first space and the second partial space,

the length of the first partial space is longer than the length of the second partial space and longer than the length of the second partial space.

9. Offshore structure according to claim 1,

the flow attenuating structure includes:

and a rear inclined plate disposed above the first damping member and inclined downward toward the front.

10. Offshore structure according to claim 1 or 9, further comprising:

a rear guide plate provided between a water surface inside the moon pool and the first damping member and protruding forward from a rear side wall of the moon pool;

and a front guide plate provided between the water surface inside the moon pool and the second damping member and protruding rearward from a front side wall of the moon pool.

11. Offshore structure according to claim 1 or 9, further comprising:

and an inclined block disposed at a front side portion of the first damping member and having a front end surface inclined upward toward the front inclined plate.

12. Offshore structure according to claim 8,

the flow attenuating structure further comprises:

a front guide plate provided between a water surface inside the moon pool and the second damping member and protruding rearward from a front side wall of the moon pool;

a rear guide plate provided between a water surface inside the moon pool and the first damping member and protruding forward from a rear side wall of the moon pool; and

and the blocking plate is arranged between the water surface in the moon pool and the rear guide plate and protrudes from the rear side wall of the moon pool.

13. An offshore structure, comprising:

a hull formed with a moon pool; and

a flow attenuating structure attenuating the flow inside the moon pool,

the flow attenuating structure further comprises:

a first damping member and a second damping member which are arranged to be spaced apart from each other;

a front inclined plate disposed above the second damping member and inclined rearward and downward;

a first stopper plate provided between a water surface inside the moon pool and the first damping member and protruding forward from a rear side wall of the moon pool;

a second blocking plate which is arranged on the water surface in the moon pool and protrudes forwards from the rear side wall of the moon pool,

the second damping member is disposed in contact with a front side wall of the moon pool facing the second damping member, and the first damping member is disposed in contact with a rear side wall of the moon pool facing the first damping member, and