JPS59184082A - Ship with device for preventing creation of bilge eddy - Google Patents

Abstract

PURPOSE:To decrease ship hull resistance and to improve heading stability, by a method wherein a rotary cylinder is mounted in a groove formed in a bilge part to prevent creation of a bilge eddy occasioned by exfoliation of the flow of water along the outside plate of a ship hull. CONSTITUTION:Rotors 8, being of rotary cylinders, are installed to the right and left sides of a bilge part 5 forming the boundary between the bottom 2 and the side 3 of a stern part 1. The rotor 8 is supported in a groove 9a formed along the bilge part 5 and in an outside plate 9 of a ship hull, and is rotated in a direction from the bottom 2 to the side 3 to accelerate the flow of water. This causes acceleration and uniformization of the flow exfoliated at the bilge part 5, resulting in the flow without any exfoliation, prevention of creation of a bilge eddy, reduction in the resistance of a ship hull, and stability in heading.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ship with improved water flow along the ship's hull.

In a conventional ship, as the stern becomes enlarged, as shown in FIG. A vortex is born.

There is a problem in that it increases hull resistance.

1. In a ship with an enlarged bow, as shown in Figure 2,
There is a problem in that the water flow 7 that flows around from the ship side 3 to the bottom 2 at the bow section 6 separates at the bilge section 5, thereby generating a bilge vortex and increasing the hull resistance.

Note that the reference numeral 16 in Fig. 1.2 indicates a water line.

The present invention aims to solve these problems by preventing the generation of bilge vortices by controlling the separation of the flow between the ship's side and the ship's bottom at the bow or stern of the ship. An object of the present invention is to provide a ship equipped with a bilge vortex prevention device that reduces hull resistance and improves course stability.

Therefore, in the ship with the bilge vortex prevention device of the present invention, four parts are formed in the bilge part in order to prevent the generation of bilge vortices due to separation of water flow along the hull outer plate, in the bilge part, It is characterized in that a rotating cylinder that accelerates the flow is attached to the same four parts.

A ship equipped with a bilge vortex prevention device as a first embodiment of the present invention will be explained with reference to the following five drawings. FIG. 3 is a perspective view schematically showing the stern section under water, and FIG.
V-1'll arrow sectional view, FIG. 5 is a cross-sectional view taken from the ■-■ arrow in FIG. In Figures 3 to 7,
The same reference numerals as in FIGS. 1 and 2 indicate substantially similar parts.

As shown in FIG. 3, rotors 8 as rotating cylinders are provided on both port and starboard sides of the bilge portion 5, which is the boundary between the bottom 2 and the ship side 3 of the stern portion 1. Each rotor 8
As shown in FIGS. 4 and 5, is supported by a waterproof bearing 12 via a rotary shaft 11 within a four part 9a provided on the hull outer plate 9 along the bilge part 5.

Note that the radius 14 of the rotor 8 is determined so that the rotor 8 follows the surface shape of the hull outer plate 90 of the visible part 5.

Further, one end of this rotating shaft 11 is connected to a drive unit 13 provided inside the ship 10, and thereby the rotor 8
can be rotated.

This drive unit 13 is controlled by a control means (not shown), and can appropriately adjust the rotation speed of the rotor 8.

With the above configuration, when the rotor 8 rotates in the clockwise rotation direction 15 in FIG. 4, as shown in FIG.
The flow of water flowing from the bottom 2 to the side 3 of the ship is accelerated. Therefore, the flow that has separated in the bilge portion 5 is accelerated and rectified, and becomes a flow 4' that is almost separated. That is, the generation of bilge vortices in the bilge portion 5 is prevented, the hull resistance can be significantly reduced, and the course stability of the hull can also be improved.

By the way, as shown in FIG. 7, prevention of bilge vortices at the bow section 6 is also carried out by the same device as at the stern section l.

That is, a rotor 8 similar to that provided in the stern part 1 is installed in the bilge part 5 between the ship's bottom 2 and the ship's side 3 on both port and starboard sides.
is provided.

However, as shown in Figures 2 and 7, in the bow section 6, the stern section l
On the contrary, the flow goes around from the ship @J3 force to the bottom 2,
The rotor 8 must be rotated in a direction opposite to the direction of rotation 15 in the stern section 1 described above.

Due to the rotation of the rotor 8, the flow from the ship side 3 to the bottom 2 of the ship 5 is accelerated and rectified, and the flow 7' without separation shown in FIG.
becomes. In this way, the hull resistance can be easily reduced even in the bow section 6.

8 to 12 show a ship equipped with a bilge vortex prevention device as a second embodiment of the present invention. IX-IX
10 is a sectional view taken along the line X-X in FIG. 8, FIG. 11 is an explanatory diagram of its operation, and FIG. In Figures 8-12.

The same reference numerals as in FIGS. 1 to 7 indicate substantially similar parts.

As shown in FIG. 8, recesses 9a and 9b are formed along the bilge portions 5 on both sides of the stern portion 1.

9C has a plurality of (three) rotors 8a and 8b.

8C is provided respectively, which allows the mouth to reach 8a.
, 8b, and 8c are provided in series.

As shown in FIG. 10, the rotor 8a is supported by a bearing 12 via a rotating shaft 11 in a recess 9a.
Furthermore, this rotor 8a is rotated by power being transmitted by a bell) 1B hung between a pulley 17 attached to one end of the rotating shaft 11 and a pulley 17' attached to a drive unit 19. It has become.

Note that the other rotors 8b and 8C are also rotated by similar means.

Further, each rotor 8a, 8b, 8c has a separate
A drive unit 19 is provided, and each drive unit 19 is controlled by a separate control means (not shown).

Therefore, each rotor 8a, 8b, 8c can rotate at a different number of rotations.

By the way, the velocity of the flow from the bottom 2 to the ship side 3 in the bilge part 5 of the stern part 1 varies depending on the position of the bilge part 5. As shown in the figure, the flow 4'' can be accelerated and rectified by rotating each of the rotors 8a, 8b, and 8c at different rotational speeds according to the speed of the flow at each position. The generation of bilge vortices can be more effectively prevented than in the case of only one.

Also, in the bow section 6, as shown in FIG. 12, there are a plurality of (three) rotors 8a, 8b.

A similar effect can be achieved by providing 8C.

At this time, the rotation direction of the rotors 8a, 8b, and Be is the rotation direction 15 of the rotors in the bow section 1 described above (see FIG. 9).
This is the opposite direction.

Note that the openings 8, 8a, 8b, and 8c may be solid or hollow.

As detailed above, according to the ship equipped with the bilge vortex prevention device of the present invention, in the bilge part, in order to prevent the generation of bilge vortices due to separation of water flow along the hull outer plate. With a simple configuration in which a recess is formed and a rotating cylinder that accelerates the flow is attached to the recess, it is possible to sufficiently prevent the generation of bilge vortices due to separation of water flow in the bilge part of the hull. , this K has the effect of significantly reducing the hull resistance, and also has the advantage of improving the hull course stability.

[Brief explanation of drawings]

Figures 1 and 2 show a conventional ship; Figure 1 is a perspective view schematically showing the stern section below the water surface, Figure 2 is a perspective view schematically showing the bow section below the water surface, and Figure 3 is a perspective view schematically showing the bow section below the water surface. 7 to 7 show a ship equipped with a bilge vortex prevention device as a first embodiment of the present invention, FIG. 3 is a perspective view schematically showing the stern section under water, and FIG. 5 is a sectional view taken along the line V-■ in FIG. 3, FIG. 6 is an explanatory diagram of its operation, and FIG. Figures 8 to 12 show a ship equipped with a bilge vortex prevention device as a second embodiment of the present invention. Figure 8 is a perspective view schematically showing the stern section under water, and Figure 9 is a perspective view of the vessel equipped with a bilge vortex prevention device as a second embodiment of the present invention. −
FIG. 10 is a sectional view taken along the line X--X in FIG. 8, FIG. 11 is an explanatory diagram of its operation, and FIG. 12 is a perspective view schematically showing the bow section below the water surface. l...Stern, 2...Bottom, 3...Ship side, 4゜4', 4
”...Flow, 5...Bilge section, 6.. Bow section, 7, 7
'++ e Flow, 8.8a, 8b, 8cm・Rotor as a rotating cylinder, 9・・Hull outer plate, 9a・・Concavity, 10・
・Inboard, 11...Rotating shaft, 12...Bearing, 13..., Drive unit, 14...Rotor radius, 15...Rotor rotation direction, 16@Fist water line, 17.17'...Pulley,
18... Belt, Ig... Drive unit. Sub-Agent Patent Attorney Yoshihiko Iinuma Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 and Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12

Claims (1)

[Claims] In order to prevent the generation of bilge vortices due to the separation of the water flow along the outer skin of the ship, four parts are formed in the bilge part of a ship, and a rotating cylinder is installed in the concave part to accelerate the flow. A ship equipped with a bilge vortex prevention device, characterized in that: