JPS6234888A

JPS6234888A - Shape of bow

Info

Publication number: JPS6234888A
Application number: JP60172389A
Authority: JP
Inventors: Hikari Yagi; 八木　光; Shunji Soejima; 副島　俊二; Toshio Nakajima; 利夫中嶋; Masao Nito; 仁藤　雅夫
Original assignee: Mitsui Engineering and Shipbuilding Co Ltd
Current assignee: Mitsui Engineering and Shipbuilding Co Ltd
Priority date: 1985-08-07
Filing date: 1985-08-07
Publication date: 1987-02-14

Abstract

PURPOSE:To reduce the wave making resistance by projecting the lower part of a valve arranged in a bow part, under the base line. CONSTITUTION:A bow valve 1 is constituted of the part 2 forming the curved line A-B projecting forward from the cross point A with the draught surface WL1 in full loading and the part 3 forming the curved line B-C-D projecting towards under the base line B.L from the B point. When the depth to the draught WL1 in the full load state from the base line B.L is set d1, and the distance between the base line B.L and the C point is set d2, and the horizontal distance between D and C is set (l), d2 and l are prescribed so that the following equation is satisfied. In other words, 0.05d1<=d2, 10d2<=lo. From the above- described equation, the draught at the bow part can be increased substantially, and the power can be reduced by reducing the wave making resistance. Further, the latter equation is the necessary condition for making smooth the flow succeeding to the lowest point C.

Description

【発明の詳細な説明】〔技術分野〕本発明は船首形状、特に船首のバルブ形状に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to the shape of a ship's bow, and more particularly to the shape of a bow valve.

[Prior art]

従来、船舶の造波抵抗の軽減を図るため、船首部船体形
状、特に船首バルブについて色々と研究されている。Conventionally, in order to reduce the wave-making resistance of ships, various studies have been conducted on the shape of the bow hull, especially the bow valve.

ところで、一般的に同一速度の場合、吃水が浅いと砕波
抵抗が大きくなる傾向があり、その改善が要望されてい
る。By the way, in general, when the speed is the same, the wave breaking resistance tends to increase when the stutter is shallow, and there is a desire to improve this.

〔発明１の目的〕本発明はバラスト状態における砕波抵抗の減少を図り、
もって、その状態における造波抵抗の減少を図ることを
目的とするものである。[Object of invention 1] The present invention aims to reduce wave breaking resistance in a ballast state,
Thus, the purpose is to reduce the wave-making resistance in that state.

[Structure of the invention]

上記目的を達成する本発明の船首形状は、船首部に配設
したバルブの下部をベースラインより下方に突出させた
ことを特徴とするものである。The bow shape of the present invention that achieves the above object is characterized in that the lower part of the valve disposed in the bow portion protrudes below the baseline.

〔Example〕

以下、図面により本発明の実施例について説明する。 Embodiments of the present invention will be described below with reference to the drawings.

第１図は、本発明にかかる船首形状の側面図であるが、
この船首バルブ１のプロファイルは、満載状態における
吃水面ＷＬ、との交点Ａより前方に突出した曲線Ａ−Ｂ
を成形する部分２、及び前記Ｂ点よりベースラインＢ、
Ｌ、の下方に突出した曲線Ｂ−Ｃ−Ｄを形成する部分３
とから構成されている。FIG. 1 is a side view of the bow shape according to the present invention,
The profile of this bow valve 1 is a curved line A-B that protrudes forward from the intersection A with the water level WL in a fully loaded state.
2, and base line B from the point B,
Portion 3 forming a downwardly protruding curve B-C-D of L.
It is composed of.

他方、ベースラインＢ、Ｌ、から満載状態の吃水ＷＬ、
までの深さをｄｌ、ベースラインＢ。On the other hand, from the baselines B and L, the fully loaded state of hiccups WL,
Depth to dl, baseline B.

Ｌ、の下方部分Ｂ〜ＣとベースラインＢ、Ｌ。Lower parts B to C of L, and baselines B and L.

との距離をｄ２、更にＦ、Ｐｌ＆方のＤ点より前方で、
下方部分が存在するものとして、Ｄ点と０点との水平距
離をｌとすると、ｄ２およびｌは、次式ｆｌｙ、　（２
）を満足するように規制される。d2, further ahead of point D on F, Pl&,
Assuming that there is a lower part and assuming that the horizontal distance between point D and point 0 is l, d2 and l are calculated by the following formula fly, (2
) is regulated to satisfy the following.

すなわち、０．０５ａｔ　≦ｄ２　・・・・・・・・・　（１）１
０ｄ２≦ｌ　　・・・・・・・・・　（２）ところで、
第２図に示すように、同一速度においては、船首部吃水
が浅いと破波抵抗が大きい傾向がある。That is, 0.05at≦d2 (1)1
0d2≦l ・・・・・・・・・ (2) By the way,
As shown in FIG. 2, at the same speed, the shallower the bow water, the greater the wave breaking resistance.

上記（１）式を満たすことによって、実質上、船首部吃
水を深めることができ、破波抵抗の減少を通して必要馬
力の軽減が実現できる。By satisfying the above formula (1), it is possible to substantially deepen the bow water, and through the reduction of breaking wave resistance, it is possible to reduce the required horsepower.

一方、（２）式は、下部部分の最下点Ｃ点から後方の流
れが滑らかに流れるための必要条件である。On the other hand, Equation (2) is a necessary condition for the rear flow to flow smoothly from the lowest point C of the lower portion.

上記のように、本発明においては、船首バルブ１の下部
がベースラインＢ、Ｌ、より下方に突出しているため、
バラスト状態においても、実質上、船首吃水が深くなる
ようになる。As mentioned above, in the present invention, since the lower part of the bow valve 1 protrudes below the baselines B and L,
Even in the ballast state, the bow water becomes substantially deeper.

したがって、バラスト状態における砕波抵抗が減少し、
造波抵抗が減少するようになる。Therefore, wave breaking resistance in ballast condition is reduced,
Wave resistance will be reduced.

〔Effect of the invention〕

上記のように、本発明は、船首部に配設したバルブの下
部をベースラインより下方に突出させたので、バラスト
状態においても、実質上、船首吃水が深くなる。As described above, in the present invention, since the lower part of the valve disposed in the bow portion protrudes below the baseline, the bow droop becomes substantially deeper even in the ballast state.

したがって、本発明によれば、バラスト状態における砕
波抵抗が減少し、もって、その状態における造波抵抗が
減少する。Therefore, according to the present invention, the wave-breaking resistance in the ballast state is reduced, and thus the wave-making resistance in that state is reduced.

[Brief explanation of the drawing]

第１図は本発明にかかる船首形状の側面図、第２図は砕
波抵抗と船首部吃水との関係を示す図である。１・・・船首バルブ、２．３・・・バルブ部分。FIG. 1 is a side view of the bow shape according to the present invention, and FIG. 2 is a diagram showing the relationship between wave breaking resistance and bow water. 1... Bow valve, 2.3... Valve part.

Claims

[Claims]

A bow shape characterized by the lower part of the valve located at the bow protruding below the baseline.