WO2010128781A2

WO2010128781A2 - Floating structure balance maintaining apparatus

Info

Publication number: WO2010128781A2
Application number: PCT/KR2010/002797
Authority: WO
Inventors: Min Woo Kim
Original assignee: Min Woo Kim
Priority date: 2009-05-08
Filing date: 2010-05-03
Publication date: 2010-11-11
Also published as: KR101089651B1; KR20100121078A; WO2010128781A3; WO2010128781A9

Abstract

The present invention relates to a floating structure balance maintaining apparatus. The floating structure balance maintaining apparatus according to the present invention maintains balance of a floating structure by weight of a fluid contained in the apparatus and a drag force generated by surface area when moved by an external force while coupled to the floating structure. According to the present invention, the floating structure balance maintaining apparatus according to the present invention is connected to a floating structure separately from an anchor and may suppress a drastic movement caused by an external force such as by wind or waves with the aid of weight of the fluid contained in the body and a drag force generated when moved by the external force, thus maintaining balance of the floating structure.

Description

FLOATING STRUCTURE BALANCE MAINTAINING APPARATUS

The present invention relates to a floating structure balance maintaining apparatus, and more specifically to a floating structure balance maintaining apparatus that is connected to a floating structure separately from an anchor to suppress a drastic movement caused by waves or external forces, thus maintaining balance of the floating structure.

In general, a floating structure, such as a ship, may be subjected to damage that leads to losses of life and property while drastically moved in all directions due to an external force, such as waves or wind.

An existing anchor which is used to anchor a floating structure at a certain location suffered from problems, such as heavy weight and difficulty to install or dismantle and showed its own limitation in preventing the sway of the floating structure especially when strong waves or wind occur, such as disconnection of a rope or chain connecting the anchor to the floating structure.

The present invention has been designed to solve the problems and an object of the present invention is to provide a floating structure balance maintaining apparatus that is connected to a floating structure separately from an anchor to suppress a drastic movement caused by an external force such as by wind or waves with the aid of weight of the fluid contained in the body and a drag force generated when moved by the external force, thus maintaining balance of the floating structure.

According to the present invention, there is provided a floating structure balance maintaining apparatus maintaining balance of a floating structure by weight of a fluid contained in the apparatus and a drag force generated by surface area when moved by an external force while coupled to the floating structure.

The floating structure balance maintaining apparatus includes a body whose top portion is open so that the fluid is accommodated in the body; a pendulum provided at a central bottom portion of the body; and a floating structure coupling member uprightly fixed at a central portion of the pendulum to be coupled with the floating structure.

The body is shaped as a reversed corn.

The body includes an extending wall protruding from the periphery and a plurality of holes to generate a pressure drag and a surface drag when the fluid moves to the extending wall.

A fixing member is radially provided at the extending wall to support the inner surface of the extending wall.

A connecting member for salvage is further provided at the outer surface of the body and the extending wall.

The extending wall is formed to be slopped.

The floating structure balance maintaining apparatus according to the present invention is connected to a floating structure separately from an anchor and may suppress a drastic movement caused by an external force such as by wind or waves with the aid of weight of the fluid contained in the body and a drag force generated when moved by the external force, thus maintaining balance of the floating structure

Theoretically, the entire drags exerted to an object are equal to the sum of a friction drag and a pressure drag. The extending wall may increase the friction drag.

The flow of fluid downstream from a separation point may be characterized by an irregular turbulent vortex that includes a boundary layer caught in the backflow. This situation is expanded to downstream until the vortex disappears by viscous friction. The region where is completely subject to turbulence is called “turbulent wake” (see Reference Fig. 1)

(Reference Fig. 1) turbulent wake generated at the rear side of a plate perpendicular to the direction of flow

Since the rotational kinetic energy of a vortex cannot be transformed to an increase in pressure, pressure in the wake is kept similar to pressure at the separation point as can be known from an ideal hydrodynamic theory. The pressure in the wake is always smaller than pressure in the front stagnation, and this creates a net pressure difference to move an object in the flowing direction. It is called “pressure drag”.

Resultantly, the floating structure balance maintaining apparatus according to the present invention may suppress movement of the flowing structure coupled with the apparatus by maximizing the turbulent wake generated at the rear side of the plate and vortexes (turbulent wake) generated when the fluid passes through the plurality of holes to increase pressure drag, thus maintaining balance of the floating structure.

Fig. 1 is a plan view illustrating that a floating structure is coupled with four floating structure balance maintaining apparatuses according to an embodiment of the present invention.

Fig. 2 is a perspective view illustrating a floating structure balance maintaining apparatus according to an embodiment of the present invention.

Fig. 3 is a side cross sectional view illustrating a floating structure balance maintaining apparatus according to an embodiment of the present invention.

Fig. 4 is a plan view illustrating a floating structure balance maintaining apparatus according to an embodiment of the present invention.

10: floating structure

100: floating structure balance maintaining apparatus

110: body 112: extending wall

114: hole 120: pendulum

122: floating structure coupling member

124: connecting member for salvage

130: fixing member

Hereinafter, a floating structure balance maintaining apparatus according to an embodiment of the present invention will be described with reference to accompanying drawings.

A floating structure balance maintaining apparatus 100 according to an embodiment of the present invention, as shown in Figs. 1 to 4, maintains its balance by the weight of fluid contained in a body 110 and a drag force generated according to the surface area of the body 110 with a floating structure 10 tied with at least one rope or chain when moved by an external force in the fluid.

At this time, the floating structure balance maintaining apparatus 100 includes the body 110, a pendulum 120, a floating structure coupling member 122, a connecting member 124 for salvage, and a fixing member 130. Although it has been exemplified in this embodiment that the floating structure is tied up at four spots, the number of the spots where the ropes or chains are coupled may be increased or decreased.

The body 110 may be formed of a metallic material, a nonmetallic material, or plastics. The body 110 is shaped as a reversed corn whose top portion is open so that a receiving space may be formed in the body 110. A slopped extending wall 112 is protrudingly provided along the upper periphery of the body 110. The body 110 plays a role to reduce the cross section area to facilitate a vertical motion.

The reason why the lower part of the floating structure balance maintaining apparatus 100 is shaped as a reversed corn is to minimize a drag force so that the body 110 may be easily moved upon a vertical motion. On the contrary, since the top portion of the body 110 is flat, the body 110 may cause water resistance when being elevated.

The extending wall 112 serves to increase fluid resistance (eddy resistance) when the body 110 vertically moves as well as to accommodate a constant amount of water in the body 110. The extending wall 112 includes a plurality of holes 114 through which water passes to generate fluid resistance. The holes 114 may be regularly or irregularly arranged to have a plurality of rows. In this embodiment, the holes 114 are formed to have two rows that are regularly arranged.

Due to the plurality of holes 114 of the extending wall 112, the section area of the extending wall 112 is increased so that a drag force (wave drag, form drag, and pressure drag) may occur more frequently. Specifically, when an external force by wave or wind is exerted to the extending wall 112, high pressure and high shock wave are induced at the surface of the body 110 to which the external force is exerted and low pressure and low expansion wave are induced at its opposite surface, thus generating wave drag, form drag, and pressure drag.

The pendulum 120 is provided at the central bottom portion of the body 110 to adjust the weight balance and facilitate the vertical motion of the body 110. The pendulum 120 may function as an anchor for the floating structure balance maintaining apparatus 100 located under water.

The floating structure coupling member 122 is uprightly fixed at the central top portion of the pendulum 120. On one end, the pendulum 120 has a ring for hanging a rope or chain that connects between the ring and the floating structure 10.

The connecting member 124 for salvage is provided at the extending wall 112 perpendicularly to the floating structure coupling member 122. The connecting member 124 for salvage has a ring at its end for hanging a rope or chain that connects between the ring and the floating structure 10. The position of the connecting member 124 for salvage is not specifically limited.

The floating structure coupling member 122 and the connecting member 124 for salvage is connected to a rope or chain with low surface area in order to minimize water resistance exerted to the floating structure balance maintaining apparatus 100 upon anchoring or salvaging the floating structure 10.

The fixing member 130 is radially provided to support the inner surface of the extending wall 112 at at least two spots, thus preventing the floating structure coupling member 122 from swaying. Further, the fixing member 130 connects and fixing the inner surface of the extending wall 112 with the floating structure coupling member 122 to generate an eddy current.

The fixing member 130 may be formed in the shape of, but not limited to, "1", "┼", "×", "

", or"*".

The drag in the fluid is proportional to speed and area. If the area is increased to have a planar structure, the apparatus moves irregularly in all directions upon a vertical motion. Further, the area of the apparatus is so large that a collision may occur between the apparatuses. Accordingly, the apparatus 100 according to an embodiment is made of a lighter material, has reduced cross section area, and maintains the balance of the floating structure 10 by using a friction drag exerted to the extending wall 112 of the body 110, a pressure drag exerted to the plurality of holes 114 formed at the extending wall 112, and the weight of water contained in the body 110.

In terms of fluid dynamics, a drag is defined as a force exerted against the motion of an object in the fluid.

According to a drag equation, a drag exerted against the motion of an object in the fluid is calculated as follows:

where

is drag, ρ is the density of fluid, v is the speed of the object relative to the fluid, A is a reference area, Cd is the drag coefficient, and

is a unit vector representing the direction of the speed (minus sign ‘-’ means the drag is exerted in the opposite direction of the speed vector)

The reference area A is involved in the area of the object projected onto a plan perpendicular to the motion direction of the object. Accordingly, the floating structure balance maintaining apparatus 100 according to an embodiment may salvage the floating structure 10 by connecting between the connecting member 124 for salvage and the floating structure 10 with a rope or chain.

When it is needed to anchor the floating structure 10, an anchor is dropped and the floating structure 10 is tied up at four spots by ropes or chains connecting between the floating structure coupling member 122 and the floating structure 10.

When fluid is waved, a left and right vibration occurs near the bottom of the fluid while an up and down vibration occurs near the surface of the fluid. Accordingly, the apparatus 100 is positioned at the bottom of the fluid to be applicable to the left and right vibrating situation.

As the fluid flows in the body 110, the apparatus 100 is sunk at the bottom of the fluid due to the material of the pendulum 120 and the body 110. At this time, the body 110 may be smoothly moved up and down because the lower portion of the body 110 is shaped as a reversed corn.

When the floating structure 10 is shaken in left, right, upper, and lower directions due to an external force generated by wave or wind, the sinking motion of the body 110 is smoothly performed thanks to the lower portion of body 110 shaped as a reversed corn while the lifting motion of the body 110 is delayed due to resistance by the flat upper portion of the body 110.

When the floating structure 10 is shaped in left and right directions, the left and right motion of the apparatus may be delayed thanks to the weight of water enclosed in the body 110 by the extending wall 112, which is provided at the upper periphery of the body 110, and an additional drag (pressure drag) generated by the plurality of holes 114, which are provided to increase fluid resistance (eddy resistance) upon vertical motion of the body 110.

At this time, the extending wall 112 may increase the frequency of occurrence of a drag (wave drag, form drag, and pressure drag) due to the surface area increased by the plurality of holes 114. The fixing member 130 may connect the inner surface of the extending wall 112 with the floating structure coupling member 122 to prevent the floating structure coupling member 122 from being swayed and generate an eddy current.

More specifically, the eddy drag is first increased by the fixing member 130 and the surface drag and pressure drag are secondly increased when water is discharged from the body 110 and the extending wall 112 to the outside. Accordingly, a vortex flow is generated through the fixing member 130 and the holes 114 of the extending wall 112, which causes a drag. An external force generated by wind or wave is adapted to be substantially equal to the drag generated at the body 110, so that the floating structure 10 may be maintained at a balanced state where sway is minimized.

The invention has been explained above with reference to exemplary embodiments. It will be evident to those skilled in the art that various modifications may be made thereto without departing from the broader spirit and scope of the invention. Further, although the invention has been described in the context its implementation in particular environments and for particular applications, those skilled in the art will recognize that the present invention's usefulness is not limited thereto and that the invention can be beneficially utilized in any number of environments and implementations. The foregoing description and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims

A floating structure balance maintaining apparatus maintaining balance of a floating structure by weight of a fluid contained in the apparatus and a drag force generated by surface area when moved by an external force while coupled to the floating structure.
The floating structure balance maintaining apparatus of claim 1, comprising:

a body whose top portion is open so that the fluid is accommodated in the body;

a pendulum provided at a central bottom portion of the body; and

a floating structure coupling member uprightly fixed at a central portion of the pendulum to be coupled with the floating structure.
The floating structure balance maintaining apparatus of claim 2, wherein the body is shaped as a reversed corn.
The floating structure balance maintaining apparatus of claim 3, wherein the body includes an extending wall protruding from the periphery and a plurality of holes to generate a pressure drag and a surface drag when the fluid moves to the extending wall.
The floating structure balance maintaining apparatus of claim 4, wherein a fixing member is radially provided at the extending wall to support the inner surface of the extending wall.
The floating structure balance maintaining apparatus of claim 4, wherein a connecting member for salvage is further provided at the outer surface of the body and the extending wall.
The floating structure balance maintaining apparatus of claim 3, wherein the extending wall is formed to be slopped.