JPH0439836Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to the shape of the bow of a ship.

[Conventional technology]

FIG. 2 shows a side view of the conventional hull, FIG. 3 shows a cross-sectional view taken along the arrows in FIG. 2, and FIG. 4 shows a diagram of the vortex flowing into the propeller. A bow 02 is provided at the front end of the hull 1, projecting below the waterline 10 and forward of the bow perpendicular FP. In addition, a bottom 3 is provided at the bottom, and a stern member 4 is provided at the stern.
A propeller 5 and a rudder 6 are provided behind the stern member 4, respectively. The hull 1 is formed symmetrically with respect to the hull centerline, and the bow 02 is also formed symmetrically with respect to the hull centerline 7, as shown in FIG.

When the hull 1 having the above configuration is traveling forward by rotating the propeller 5, the propeller 5
A vortex flow 09 symmetrical with respect to the hull center line 7 as shown in FIG. 4 flows into the vessel. The flow velocity component of this vortex 09 in the rotational direction of the propeller 5 is locally a component in the direction of rotation of the propeller 5, but the average value when the propeller 5 rotates once is zero. Note that 8 is the propeller tip trajectory.

[Problems that the idea aims to solve]

However, in the bow shape of such a conventional ship, when the propeller rotates, a rotational flow is generated behind the propeller in the same direction as the rotational direction of the propeller, which is one of the causes of a decrease in propeller efficiency. However, since the flow velocity component of the vortex flowing into the propeller in the direction of rotation of the propeller is zero as an average value during one revolution, there is a problem that the rotational flow in the wake of the propeller cannot be increased or decreased.

This invention was proposed in view of the above-mentioned problems, and by bending the forward end of the bow on the side where the propeller blades rise when the propeller rotates forward, the rotational flow behind the propeller is reduced. It is an object of the present invention to provide a bow shape of a ship that is formed asymmetrically so that the bow shape of the ship is asymmetrically formed.

[Means for solving problems]

For this reason, the shape of the bow of the ship of the present invention is such that when the propeller rotates forward, the bow of the ship has a bow that protrudes forward from the bow perpendicular of the hull below the waterline. ,
The ship's bow is bent and is asymmetrical with respect to the hull centerline.

[Effect]

With the above configuration, when the propeller rotates forward, the vortex flowing into the propeller is shifted from the centerline of the ship to the side of the propeller blade rising, so the flow velocity component of the vortex in the direction of one propeller rotation is in the opposite direction to the propeller rotation direction. , thereby reducing the rotational flow in the wake of the propeller.

〔Example〕

An embodiment of the present invention will be explained with reference to the drawings.
FIG. 1 is a plan sectional view thereof. Note that FIG. 1 is a view taken in the direction of the ~ arrow in FIG. 2. FIG. 2 is a side view thereof, and FIG. 5 is a drawing of the vortex flowing into the propeller.

A bow 2 is provided at the front end of the hull 1 and protrudes below the waterline 10 and forward of the bow perpendicular FP. Further, a bottom 3 is provided at the bottom, a stern member 4 is provided at the stern, and a propeller 5 and a rudder 6 are provided behind the stern member 4, respectively. The bow 2 protrudes forward from the bow perpendicular FP, and when the propeller 5 rotates forward, the blades of the propeller 5 are bent toward the rising side, so that the bow 2 is formed asymmetrically with respect to the hull centerline 7. .

When the hull 1 equipped with the bow 2 configured as described above is traveling forward due to the rotation of the propeller 5, the flow in the stern section is bent toward the bent side of the bow 2 due to the action of the bow 2. It will be done. Therefore, propeller 5
As shown in FIG. 5, the vortex flowing into the vortex 9 shifts from the hull centerline 7 to the side where the blades of the propeller 5 rise, so the flow velocity component of the vortex 9 in the rotational direction of the propeller 5 is equal to The average value is opposite to the rotation direction of the propeller 5. This action reduces the rotational flow in the wake of the propeller 5, improving propeller efficiency.

[Effect of idea]

In the bow shape of the ship of the present invention described above, the vortex flowing into the propeller is in the opposite direction to the propeller rotation direction, so the propeller wake is created by the vortex flowing into the propeller and the rotational flow induced by the propeller itself. This has the advantage of reducing the rotational flow generated in the wake of the propeller, greatly improving the propulsion performance of the ship.

[Brief explanation of drawings]

Figures 1, 2 and 5 are drawings showing the shape of the bow of a ship as an embodiment of the present invention. Its side view, FIG. 5, is a drawing of the vortex flowing into the propeller. Figures 3 and 4 are drawings showing the shape of the bow of a conventional ship;
FIG. 4 is a diagram of the vortex flowing into the propeller. 1... Hull, 2... Bow, 3... Bottom, 4...
Stern material, 5... propeller, 6... rudder, 7... hull center line, 8... propeller tip trajectory, 9... vortex,
10...Water line.

Claims (1)

[Scope of utility model registration request] In the bow shape of a ship that has a bow protruding forward from the bow perpendicular of the hull below the waterline, the bow is bent toward the side of the ship where the propeller blades rise when the propeller rotates forward, relative to the hull centerline. The bow shape of a ship is characterized by its asymmetrical shape.