KR20000004695A - Resistance reducing appratus of ship using electromagnetic force generating device - Google Patents

Resistance reducing appratus of ship using electromagnetic force generating device Download PDF

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Publication number
KR20000004695A
KR20000004695A KR1019980026186A KR19980026186A KR20000004695A KR 20000004695 A KR20000004695 A KR 20000004695A KR 1019980026186 A KR1019980026186 A KR 1019980026186A KR 19980026186 A KR19980026186 A KR 19980026186A KR 20000004695 A KR20000004695 A KR 20000004695A
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South Korea
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electromagnetic force
ship
stern
force generating
generating device
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KR1019980026186A
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Korean (ko)
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하문근
백부근
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이해규
삼성중공업 주식회사
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Priority to KR1019980026186A priority Critical patent/KR20000004695A/en
Publication of KR20000004695A publication Critical patent/KR20000004695A/en

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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T70/00Maritime or waterways transport
    • Y02T70/10Measures concerning design or construction of watercraft hulls

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Abstract

PURPOSE: A resistance reducing apparatus is provided to reduce the resistance generated from the stern of a ship. CONSTITUTION: A resistance reducing device of a ship is attached at a deeply curved part(3') of the stern(3) of a ship covering with a specific width; an electromagnetic force generating apparatus(20) of a resistance reducing device(10) is established to flow the electromagnetic force from the stem of a ship to the stern(3) in the same direction as water flows along the stern; the electromagnetic force generating device(20) is constituted in tile-shape by arranging the making devices(30) of much magnetic field and many electric field generating device(40).

Description

전자기력 발생장치를 이용한 선박의 저항 감소 장치Reduction device of ship using electromagnetic force generator

(기술분야)(Technology)

본 발명은 선박의 선미부에서 발생하는 저항을 감소시키기 위한 장치에 관한 것이며, 보다 상세하게는 전자기력을 발생시키는 전자기력 발생장치를 이용하여 선박의 선미부에서 발생하는 저항을 감소시키는 장치에 관한 것이다.The present invention relates to a device for reducing the resistance generated at the stern of the ship, and more particularly to a device for reducing the resistance generated at the stern of the ship by using an electromagnetic force generating device for generating an electromagnetic force.

(배경기술)(Background)

도1에 도시된 바와 같이, 선박(1)은 항해시 물의 저항을 최소화하도록 유선형으로 되어 있지만, 그 선미부(3)는 선박(1)의 다른 어떤 부분보다도 뭉뚝하게 형성되어 있으며, 따라서 항해시 유선형의 선박(1)을 따라 흐르는 물의 흐름(4)은 선미부(3)에 이르러 그 흐름이 깨어지면서 많은 유체 에너지를 잃게 된다. 또한, 선미부(3)의 후방에서의 물의 유동도 선미부(3)를 지나온 후류의 영향을 받아 매우 불완전하게 되어 선박(1)의 형상에 기인한 저항이 더욱 커지게 된다. 이러한 선미부(3)의 형상에 따른 저항증가는 선박의 속도를 저하시켜, 보다 큰 마력의 엔진을 필요하게 하고 연료 사용량을 증가시키는 요인이 된다.As shown in Fig. 1, the ship 1 is streamlined to minimize water resistance when sailing, but its stern portion 3 is formed more blunt than any other part of the ship 1, and thus, when sailing. The stream of water 4 flowing along the streamlined vessel 1 reaches the stern 3 and loses a lot of fluid energy as the flow is broken. In addition, the flow of water in the rear of the stern 3 is also very incomplete under the influence of the wake passing through the stern 3, so that the resistance due to the shape of the ship 1 becomes larger. Increasing resistance according to the shape of the stern portion 3 lowers the speed of the ship, which requires a larger horsepower engine and increases fuel consumption.

또한, 도2에 도시된 바와 같이, 선미부(3)의 유동 불안으로 인하여 프로펠러(5)에 유입되는 물의 유입속도가 불균일하게 되어 프로펠러(5)의 추진 효율을 저하시키는 요인으로 작용한다.In addition, as shown in Figure 2, due to the unstable flow of the stern portion 3, the inflow rate of the water flowing into the propeller 5 is non-uniform, which acts as a factor to lower the propulsion efficiency of the propeller (5).

이와 같은 선미부의 유동 불안은, 급격한 각도로 변하는 선미부 형상에 따른 경계층의 박리 현상에 상당한 원인이 있는 것으로 보인다. 즉, 물의 흐름에 있어서 그 점성의 영향은 물이 접하는 물체의 표면 근처에 서 나타나고, 이런 점성의 영향을 받는 물체 표면 근처의 얇은 층을 경계층(boundary layer)이라고 하는 바, 유선형의 선박을 따라 흐르는 물은 선미부에 이르러 박리되게 되므로 그 후류의 흐름을 매우 불완전하게 하는 것이다.Such flow instability of the stern seems to have a significant cause in the peeling phenomenon of the boundary layer according to the shape of the stern which changes at a sharp angle. In other words, the influence of viscosity on the flow of water appears near the surface of an object in contact with water, and a thin layer near the surface of the object affected by this viscosity is called a boundary layer, flowing along a streamlined vessel. Since water reaches the stern and peels off, the downstream flow is very incomplete.

따라서, 선미부의 형상에 따른 경계층의 박리 현상을 지연시킬 수 있다면, 경계층 박리로 인한 저항 증가를 감소시킬 수 있을 것이다.Therefore, if the delamination of the boundary layer according to the shape of the stern portion can be delayed, an increase in resistance due to the boundary layer delamination may be reduced.

따라서 본 발명의 목적은, 선박의 선미 형상에 기인한 경계층의 박리 현상에 의해 발생하는 선박의 저항 증가를, 전자기력을 이용하여 경계층의 박리 현상을 지연시키므로써 감소시키고자 하는 것이다.Accordingly, an object of the present invention is to reduce the increase in resistance of a ship caused by the peeling phenomenon of the boundary layer due to the stern shape of the ship by delaying the peeling phenomenon of the boundary layer by using electromagnetic force.

도1은 일반적인 선박의 물의 흐름을 보여주는 개략도,1 is a schematic view showing the flow of water of a typical ship,

도2는 선미부의 유동 불안으로 인한 프로펠러에 유입되는 물의 불균일을 보여주는 개략도,Figure 2 is a schematic diagram showing the nonuniformity of the water flowing into the propeller due to the flow instability of the stern;

도3은 본 발명에 따른 선박의 저항 감소 장치의 설치 위치를 보여주는 선박의 저면도,3 is a bottom view of the ship showing the installation position of the resistance reduction device of the ship according to the invention,

도4는 본 발명에 따른 선박의 저항 감소 장치가 설치된 선박의 측면도,Figure 4 is a side view of a ship equipped with a resistance reduction device of the ship according to the present invention,

도5는 전자기력 발생장치의 자기장 형성수단과 전기장 발생수단의 배치 관계의 예를 보여주는 개략도,5 is a schematic view showing an example of the arrangement relationship between the magnetic field forming means and the electric field generating means of the electromagnetic force generating device;

도6은 도5의 전자기력 발생장치의 전자기력 발생 방향을 보여주는 도면.6 is a view showing an electromagnetic force generating direction of the electromagnetic force generating device of FIG.

*도면의 주요 부분에 대한 부호의 설명** Description of the symbols for the main parts of the drawings *

1: 선박 3: 선미부1: ship 3: stern

10: 저항 감소 장치 20: 전자기력 발생장치10: resistance reduction device 20: electromagnetic force generator

30: 자기장 형성수단 40: 전기장 발생수단30: magnetic field forming means 40: electric field generating means

31,32: 자석 41,42:전극31, 32: magnet 41, 42: electrode

43: 전원43: power

상기한 본 발명의 목적은, 일측 방향으로 자기장을 형성하는 자기장 형성수단과 상기 자기장 형성수단에 의해 발생된 자기장과 교차하는 방향으로 전기장을 발생시키는 전기장 발생수단을 포함하는 전자기력 발생장치가 선박의 선미부에 부착되어 있는 선박의 저항 감소 장치에 의해 달성된다.The object of the present invention described above is that the electromagnetic force generating device includes a magnetic field forming means for forming a magnetic field in one direction and an electric field generating means for generating an electric field in a direction crossing the magnetic field generated by the magnetic field forming means. Achieved by a resistance reduction device of the ship attached to the part.

상기 전자기력 발생장치는, 일정한 간격을 두고 다수 개의 N극과 S극의 자석이 교대로 나란하게 배치된 자기장 형성수단과, 상기 자석들 사이에 직류 전원에 연결된 다수 개의 양극과 음극이 교대로 나란하게 배치된 전기장 발생수단으로 구성된 다.The electromagnetic force generating device includes a magnetic field forming unit in which a plurality of N-pole and S-pole magnets are alternately arranged side by side at regular intervals, and a plurality of positive and negative poles connected to a DC power source between the magnets alternately side by side. It consists of arranged electric field generating means.

상기 전자기력 발생장치는 선미부를 따라 흐르는 물의 흐름방향, 즉 선수부 쪽으로부터 선미부 쪽을 잇는 방향으로 전자기력을 발생시키도록 선미부의 외판에 부착되며, 선미부의 외판에 부착하기 용이하도록 타일 형상으로 제작되는 것이 바람직하다.The electromagnetic force generating device is attached to the outer plate of the stern part to generate the electromagnetic force in the direction of flow of water flowing along the stern part, that is, the direction from the bow side to the stern part, and is manufactured in a tile shape to facilitate attachment to the outer plate of the stern part. desirable.

이하, 첨부 도면을 참조하여 본 발명에 따른 전자기력 발생장치를 이용한 선박의 저항 감소 장치를 상세히 설명한다. 이하의 구체예는 본 발명에 따른 선박의 저항 감소 장치를 예시적으로 설명하는 것일 뿐, 본 발명의 범위를 제한하는 것으로 의도되지 아니한다.Hereinafter, with reference to the accompanying drawings will be described in detail a device for reducing resistance of a ship using an electromagnetic force generating apparatus according to the present invention. The following embodiments merely illustrate the resistance reduction apparatus of the ship according to the present invention, but are not intended to limit the scope of the present invention.

도3은 본 발명에 따른 선박의 저항 감소 장치의 설치 위치를 보여주는 선박의 저면도, 도4는 본 발명에 따른 선박의 저항 감소 장치가 설치된 선박의 측면도, 도5는 전자기력 발생장치의 자기장 형성수단과 전기장 발생수단의 배치 관계의 예를 보여주는 개략도, 도6은 도5의 전자기력 발생장치의 전자기력 발생 방향을 보여주는 도면이다.Figure 3 is a bottom view of the ship showing the installation position of the resistance reduction device of the ship according to the present invention, Figure 4 is a side view of the ship is installed resistance reduction device of the ship according to the invention, Figure 5 is a magnetic field forming means of the electromagnetic force generating device And FIG. 6 is a diagram showing an electromagnetic force generating direction of the electromagnetic force generating device of FIG. 5.

본 발명에 따른 선박의 저항 감소 장치(10)는, 도3과 도4에 도시된 바와 같이, 선미부(3)의 굴곡이 심한 부분(3')에 일정한 폭에 걸쳐서 부착된다. 선미부(3)의 형상에 따른 저항을 감소시키기 위해서는, 선미부(3)에 접하여 흐르는 물의 유속을 증가시켜 물의 흐름(4)이 평행류가 되도록 하여야 하며, 이렇게 하면 선미부(3)에서 발생하는 와류가 감소되고 경계층의 박리 현상이 지연되므로, 경계층의 박리에 영향을 받는 후류의 폭을 줄일 수 있고, 프로펠러에 유입되는 유동의 균일성을 높여 주어 프로펠러의 효율이 증가된다.The resistance reduction apparatus 10 of the ship according to the present invention, as shown in Figs. 3 and 4, is attached to the bent portion 3 'of the stern 3 over a certain width. In order to reduce the resistance according to the shape of the stern portion 3, the flow rate of the water flowing in contact with the stern portion 3 should be increased so that the flow of water 4 becomes parallel flow, and this occurs in the stern portion 3 Since the vortex is reduced and the delamination of the boundary layer is delayed, the width of the wake affected by the delamination of the boundary layer can be reduced, and the uniformity of the flow flowing into the propeller can be increased, thereby increasing the efficiency of the propeller.

이와 같은 이유로, 본 발명에 따른 선박의 저항 감소 장치(10)의 전자기력 발생장치(20)는 선미부(3)를 따라 흐르는 물의 흐름방향과 같은 방향(F), 즉 선수부에서 선미부(3) 쪽으로 전자기력이 가해지도록 설치된다. 이로써 전자기력 발생장치(10)의 앞을 지나는 유동(F)에 운동량이 증가하여 평행류가 되며, 따라서 경계층의 박리 현상이 지연되어, 도3에 도시된 바와 같이, 경계층의 박리에 영향을 받는 후류의 폭이 줄어들게 된다.For this reason, the electromagnetic force generating device 20 of the resistance reduction device 10 of the ship according to the present invention is the same direction (F) as the flow direction of water flowing along the stern 3, that is, the stern 3 in the bow portion It is installed so that electromagnetic force is applied to it. As a result, the momentum increases in the flow F passing in front of the electromagnetic force generating device 10, resulting in parallel flow. Therefore, the peeling phenomenon of the boundary layer is delayed, and as shown in FIG. 3, the wake affected by the peeling of the boundary layer is shown. The width of the will be reduced.

전자기력 발생장치(20)는, 도5에 도시된 바와 같이, 다수의 자기장 형성수단(30)과 다수의 전기장 발생수단(40)을 나란히 배치하여 타일 형상으로 구성할 수 있다. 즉, 일정한 간격을 두고 다수 개의 N극과 S극의 자석(31,32)을 교대로 나란하게 배치하여 다수의 자기장 형성수단(30)을 설치하고, 상기 자석들(31,32) 사이에 직류 전원(S:43)에 연결된 다수개의 양극(41)과 음극(42)을 교대로 나란하게 배치하여 전기장 발생수단(40)을 설치한다.As shown in FIG. 5, the electromagnetic force generating device 20 may be arranged in a tile shape by arranging a plurality of magnetic field forming means 30 and a plurality of electric field generating means 40 side by side. That is, a plurality of magnetic field forming means 30 are installed by alternately arranging the magnets 31 and 32 of the plurality of N poles and the S poles at regular intervals, and a direct current is provided between the magnets 31 and 32. The plurality of positive electrodes 41 and the negative electrodes 42 connected to the power source S: 43 are alternately arranged side by side to install the electric field generating means 40.

이로써, 전자기력 발생장치(20)의 표면에서는 자기력선(B)과 전류밀도(J)가, 도6에 도시된 바와 같이 서로 교차하게 되고, 이런 교차 부분에서는 도5에 도시된 바와 같이 전자기력(L)이 전자기력 발생장치(20)와 평행한 방향으로 발생한다.Thus, on the surface of the electromagnetic force generating device 20, the magnetic field lines B and the current density J intersect with each other as shown in FIG. 6, and at this intersection, the electromagnetic force L as shown in FIG. It is generated in a direction parallel to the electromagnetic force generator 20.

따라서, 본 구체예의 전자기력 발생장치(20)를 타일 형상으로 제작한 저항 감소 장치(10)를, 전자기력의 방향이 유체 흐름(F)과 같은 방향이 되도록 선미부(3)의 굴곡이 심한 부분(3')에 일정한 폭으로 부착하면, 전술한 바와 같이 전자기력 발생장치(10) 앞을 지나는 유동(F)에 운동량을 증가시켜서 평행류가 되도록 한다.Therefore, the portion of the resistance reduction device 10 in which the electromagnetic force generating device 20 of the present embodiment is formed in a tile shape is a portion where the bending of the stern portion 3 is severe so that the direction of the electromagnetic force is in the same direction as the fluid flow F ( 3 ') to a certain width, as described above to increase the momentum to the flow (F) passing in front of the electromagnetic force generating device 10 to be in parallel flow.

본 발명에 따른 저항 감소 장치(10)를 실제 선박(1)에 적용함에 있어서는, 선박의 선미부(3)의 형상에 따른 레이놀즈 수(Reynolds number)에 맞도록 자기장의 세기와 전기장의 세기를 설정하여 소정의 전자기력이 발생되도록 타일을 제조할 수 있다.In applying the resistance reduction device 10 according to the present invention to the actual ship 1, the strength of the magnetic field and the electric field are set to match the Reynolds number according to the shape of the stern 3 of the ship. The tile may be manufactured to generate a predetermined electromagnetic force.

이상에서 설명한 본 발명에 따른 전자기력 발생장치를 이용한 선박의 저항 감소 장치에 따르면, 전자기력의 방향이 유체 흐름(F)과 같은 방향이 되도록 선미부(3)의 굴곡이 심한 부분(3')에 일정한 폭에 걸쳐서 전자기력 발생장치(20)를 부착하한 구성에 의하여, 선박의 선미 형상에 기인한 경계층의 박리 현상에 의해 발생하는 선박의 저항 증가를, 전자기력을 이용하여 경계층의 박리 현상을 지연시키므로써 감소시킬 수 있는 효과가 있다.According to the apparatus for reducing resistance of a ship using the electromagnetic force generating apparatus according to the present invention described above, the stern portion 3 is fixed to the severely curved portion 3 'such that the direction of the electromagnetic force is in the same direction as the fluid flow (F). With the configuration in which the electromagnetic force generating device 20 is attached over the width, the resistance increase of the ship caused by the peeling phenomenon of the boundary layer due to the stern shape of the ship is reduced by delaying the peeling phenomenon of the boundary layer by using the electromagnetic force. It can be effected.

Claims (4)

일측 방향으로 자기장을 형성하는 자기장 형성수단과 상기 자기장 형성수단에 의해 발생된 자기장과 교차하는 방향으로 전기장을 발생시키는 전기장 발생수단을 포함하는 전자기력 발생장치가 선박의 선미부에 부착되어 있는 것을 특징으로 하는 선박의 저항 감소 장치.An electromagnetic force generating device including a magnetic field forming means for forming a magnetic field in one direction and an electric field generating means for generating an electric field in a direction crossing the magnetic field generated by the magnetic field forming means is attached to the stern part of the ship. Resistance reduction device of the ship. 제1항에 있어서, 상기 전자기력 발생장치는 타일 형상인 것을 특징으로 하는 선박의 저항 감소 장치.The apparatus of claim 1, wherein the electromagnetic force generating device has a tile shape. 제1항에 있어서, 상기 전자기력 발생장치는 선미부(3)를 따라 흐르는 물의 흐름방향과 같은 방향으로 전자기력을 발생시키도록 부착된 것을 특징으로 하는 선박의 저항 감소 장치.The apparatus of claim 1, wherein the electromagnetic force generating device is attached to generate electromagnetic force in the same direction as the flow direction of water flowing along the stern (3). 제1항 내지 제3항 중 어느 한 항에 있어서, 상기 전자기력 발생장치는 일정한 간격을 두고 다수 개의 N극과 S극의 자석을 교대로 나란하게 배치한 자기장 형성수단과, 상기 자석들 사이에 직류 전원에 연결된 다수 개의 양극과 음극을 교대로 나란하게 배치한 전기장 발생수단으로 구성된 것을 특징으로 하는 선박의 저항 감소 장치.The electromagnetic force generating device according to any one of claims 1 to 3, wherein the electromagnetic force generating device comprises magnetic field forming means in which a plurality of N-pole and S-pole magnets are alternately arranged side by side at regular intervals, and a direct current is formed between the magnets. Reduction device of a ship, characterized in that consisting of electric field generating means arranged alternately side by side a plurality of positive and negative electrodes connected to the power source.
KR1019980026186A 1998-06-30 1998-06-30 Resistance reducing appratus of ship using electromagnetic force generating device KR20000004695A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20000004696A (en) * 1998-06-30 2000-01-25 이해규 Propeller attached with electromagnetic force generating device
CN108313197A (en) * 2018-02-22 2018-07-24 陈蜀乔 A kind of tactile water surface DC pulse magnetic current propulsion system of solar energy ship
CN108313250A (en) * 2018-02-22 2018-07-24 陈蜀乔 A kind of tactile water surface magnetic current propulsion system of solar energy ship

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Publication number Priority date Publication date Assignee Title
JPS6219491U (en) * 1985-07-22 1987-02-05
US5359951A (en) * 1993-02-11 1994-11-01 The United States Of America As Represented By The Secretary Of The Navy Active turbulence control using microelectrodes, permanent magnets in microgrooves
WO1995000391A1 (en) * 1993-06-25 1995-01-05 British Technology Group Usa Inc. Multiple electromagnetic tiles for boundary layer control
KR980001706A (en) * 1996-06-03 1998-03-30 김성재 Method and apparatus for reducing fluid pressure resistance and preventing cavitation using electromagnetic force

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6219491U (en) * 1985-07-22 1987-02-05
US5359951A (en) * 1993-02-11 1994-11-01 The United States Of America As Represented By The Secretary Of The Navy Active turbulence control using microelectrodes, permanent magnets in microgrooves
WO1995000391A1 (en) * 1993-06-25 1995-01-05 British Technology Group Usa Inc. Multiple electromagnetic tiles for boundary layer control
KR980001706A (en) * 1996-06-03 1998-03-30 김성재 Method and apparatus for reducing fluid pressure resistance and preventing cavitation using electromagnetic force

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20000004696A (en) * 1998-06-30 2000-01-25 이해규 Propeller attached with electromagnetic force generating device
CN108313197A (en) * 2018-02-22 2018-07-24 陈蜀乔 A kind of tactile water surface DC pulse magnetic current propulsion system of solar energy ship
CN108313250A (en) * 2018-02-22 2018-07-24 陈蜀乔 A kind of tactile water surface magnetic current propulsion system of solar energy ship

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