JPH03279095A - Ship form with catamaran type bow - Google Patents

Abstract

PURPOSE:To reduce wave making and breaking resistance and viscous resistance by a circular buttock line by forming the port side and starboard side of a center buttock line respectively into the shape of a bow. CONSTITUTION:Both bows 14 to become a catamaran type are provided in such a way as to have catamaran type bow center lines 11L, 11R on the port side and starboard side of a buttock line including the center line 12 of a hull 20. In the buttock line including the center line 12, that is, the center cross section in the longitudinal direction of the hull 20, a ship bottom forming line is to be a circular arc, so that water flow between both bows 14, 14 becomes smooth. Accordingly, in spite of the increase of frictional resistance caused by the catamaran type formation of the bow part 14, wave making and breaking resistance is reduced, and viscous resistance is also reduced by the circular arc buttock line to improve total propulsive performance and secure wide deck area.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of the bow of a wide-spread vessel, and more particularly to a bow catamaran that reduces wave-making resistance and improves performance in waves.

[Conventional technology]

For example, in a large wide ship such as an open type bulk carrier, each hold 1, which is the loading part, is a rectangular body of the same shape, as illustrated in Figures 3 to 6. Moreover, the rail 3 for the gantry crane 2 runs to the front and rear ends of the deck, and the entire deck is required up to the vicinity of the bow 10. In such a type, the cross-sectional shape of the hull, particularly at the portions corresponding to the holds 1 at the front and rear ends of the ship, is such that large protruding sponsons 4 are provided for laying rails 3, as shown in Figure 5. ing.

[Problem to be solved by the invention]

Such a large protruding sponson 4 makes the upper part of the ballast tank 5 unnecessarily large.
There is a problem in that the ship is disadvantageous in terms of both stability and economy. In addition, in order to avoid the above-mentioned gap type, a purge type gap type similar to the shape of a barge is considered, but it is said that the purge type gap type widens the waterline, which increases wave-making resistance and deteriorates performance in waves. There are also problems.

In order to solve the above-mentioned problems, the present invention provides an intermediate type that can improve wave resistance and wave performance by reducing the waterline area while securing the required deck area. The purpose is

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides a structure of a bow of a ship, characterized in that the port side and the starboard side of the center buttock line are each formed in the shape of a bow. We propose a catamaran bow hull type.

That is, in the intermediate type of the present invention, only the bow section is made into a double-hulled vessel, and the hull other than the bow section is integral.

[For production]

By making the bow a so-called catamaran, where only the bow is made into a twin hull, the two bows formed near the bow and each of the following hulls can be made into a narrow and thin ship in the waterline. can. As a result, wave-making resistance is eliminated and wave-breaking properties are improved, making it possible to improve performance in waves.

In this case, the flow of water between the two bows of the twin-hulled ship is achieved by making the baton line including the center line, in other words, the bottom shape line of the center cross section in the longitudinal direction of the hull, into an arc shape.
It can flow smoothly down the center of the hull.

[Effects of the Invention] By applying the bow catamaran of the present invention to, for example, a cargo ship having a rectangular hold, the outer shell shape can be made to match the shape of the hold, for example, with a purge type frame line, and it can be applied to a cargo ship having a rectangular hold. By eliminating the need for the huge sponsons seen in the previous model, we were able to create a reasonable and reasonable structure.

While ensuring a wide deck area that would allow for hits to be achieved across the fore and aft ends, we were also able to improve hull performance. In addition, in the present invention, although the flooded surface area increases due to the twin-hulled bow section and frictional resistance increases, the present invention reduces wave-making and wave-breaking resistance, and viscous resistance due to the arc-shaped buttock line. As a result, an overall improvement in propulsion performance can be achieved.

〔Example〕

Next, a specific embodiment of the present invention will be described with reference to the drawings.

As is clear from the profile shown in FIG. 1 and the front view shown in FIG.
4 in the form of a double body.

As shown in FIG. 2, each bow 14, which is a twin hull, has a twin hull bow centerline 11L and IIR on the port side and starboard side of the baton line including the centerline 12 of the hull 20, respectively. It is set in. Note that 13 is a water line.

These bows can be appropriately selected from, for example, a clipper bow as shown by the solid line 14, or a bulbous bow as shown by 11 [M14'.

As another embodiment, the present invention is applied to ultra-wide shallow water vessels, which are highly economical but have technical difficulties of increasing wave-making resistance and deteriorating performance in waves. When the hull type is applied, as described above, it is possible to reduce wave-making resistance and wave-breaking resistance, improve performance in waves, and provide excellent seaworthiness.

In recent years, the importance of preventing marine pollution has increased, and ultra-wide and shallow water vessels are attracting attention not only for their economic efficiency but also for the essential safety of twin-shaft vessels, and their drawbacks such as bow wave-making and
The problem of breaking waves can be solved by using this twin-hulled bow, which has great industrial applicability.

[Brief explanation of the drawing]

1 and 2 are views showing one embodiment of the present invention, in which FIG. 1 is a profile of the bow section, and FIG. 2 is a front view. 3 to 6 are diagrams showing a conventional example, and FIG. 3 is a side explanatory view;
FIG. 4 is an explanatory plan view, FIG. 5 is an explanatory cross-sectional view of a portion near the bow, and FIG. 6 is an explanatory cross-sectional view taken along the line - ■ of FIG. 1.1'... Hold 2... Gantry crane 3... Rail 4... Subonson 5... Ballast tank 10... Bow section 11L, IIR... Catamaran bow center line 12...・Hull center line 13...Water line 14. 14” ... Bow Figure 1 Figure n 2

Claims (1)

[Claims] 1. A catamaran bow structure characterized in that the port and starboard sides of the center buttock line are each shaped like a bow.