JPS60189692A - Ship - Google Patents

Abstract

PURPOSE:To improve propeller efficiency ever so better, by forming a stern outer surface at the side heating for the upper part of a propeller balde of the rotating screw propeller into a rough surface as far as two times of the height ranging from the ship's bottom to the propeller axis as compared with the stern outer surface at the side heading for the lower part. CONSTITUTION:When a propeller 2 rotates clockwise, a rough surface is formed over a range 6 of up to the waterline 7 in height 2n from the ship's bottom to the propeller axis 8 as compared with a stern part outer surface at the side (the port side) heading for an upper part of the propeller blade. Thus, a hull wake at the port side where the rough surface exists becomes increased as compared with that at the starboard, and a rising component in the drift of a current is reduced whereby a generating thrust of the propeller blade at the port side increases as much as a portion for that, therefore efficiency in the propeller as a whole is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ship with a propeller effect. .

Conventionally, the lj was equipped with a screw propeller on seven lirr tails.
On the ship t5 (Sat, 11th No. 1 Bo 4-1), sea urchin l;
The pulling force of the tail (flowing into the propellers 1 and 2) is shown in Figures 2 and 3 as vector diagrams of the flow velocity exerted on the propeller rotating surface. As shown, the flame 1" is an upward flow moving 1 degree from below.

Therefore, when the propeller 2 rotates in direction 4 around E 7 shown in FIG.
Since the thrust due to l 2 a is reduced by the amount of the above-mentioned "two rises," there is a problem that the propeller efficiency is reduced.

The present invention aims to solve these problems, and aims to provide a ship in which propeller efficiency can be improved by adjusting the wake of the ship at the stern. .

For this reason, in a ship equipped with a screw propeller at the stern, the ship of the present invention has the above-mentioned mechanism in the direction of moving the ship forward. The outer surface of the propeller blade is characterized by a rough surface extending over an area approximately twice the height from the bottom to the propeller axis, compared to the outer surface of the stern section on the side facing F)j of the same propeller blade. There is.

Hereinafter, a ship as an embodiment of the present invention will be explained with reference to the drawings. Fig. 4 is a side view of the stern, Fig. 5 is a bottom view of the stern as viewed from the top, and Fig. 6 is a bottom view of the stern as viewed from the side. is a vector diagram of the flow velocity on the propeller rotating surface.

As shown in FIGS. 4 and 5, a screw propeller 2 is attached to the rear of the stern end 1, and in this embodiment, the screw propeller 2 is rotated in a suitable direction.゛Then, this propeller 2 rotates 45 times (in the direction of moving the ship forward n1j) (
When transmitting twice I+, the outer surface of the stern part of the propeller blade on the side facing -L (/, :board side) is smaller than the outer surface of the stern part on the side facing the lower blade of the same propeller blade (starboard side). , over a range twice the height 511 from the bottom of the ship to the propeller axis 8,
In other words, the water line at a height of 211 from the bottom of the mouth () 7.4
: It is formed in lll1h1 over the range (hatched area 6 in Fig. 4.5).

For the formation of a rough surface in the rough surface forming portion 6, a method is used in which adhesive is applied to the outer surface of the tail, but the method is not limited to this method. For example, it is possible to select from various means for forming a rough surface, such as attaching a wire mesh to the outer surface of the stern section.

In addition, the sign rudder in the figure is shown, 10 shows the rll) body center line, and 11 shows the 7i: (i-board waterline).

Since the ship of the present invention is configured as described above,
The wake of the ship on the port side where the rough surface forming part 6 exists increases compared to the starboard side, and as shown in FIG. , the flow on the side is indicated by the dashed arrow, and the horizontal component of the flow velocity is reduced compared to the conventional flow indicated by the solid arrow. Therefore, the force generated by the propeller blade on the port side increases by that amount, and the effectiveness of the propeller as a whole increases by 5.
2.

In addition, the 8 blades of the screw propeller 2 are generated on the port side and the 1st side of the hull (1: The mutual imbalance of forces is alleviated, reducing the excitation force and improving the hull's course keeping performance. You can also approach it.

As detailed above, according to the ship of the present invention, in a ship equipped with a screw propeller at the stern, when the screw propeller is rotating in a direction that moves the ship forward, the propeller blade is directed upward. It is said that the outer surface of the stern section on the opposite side (rll) is formed on the January J1 surface over a range of about 2 degrees of height from the bottom of the ship to the propeller axis compared to the outer surface of the stern section on the downward side of the same propeller blade. With a simple configuration, the propeller efficiency can be greatly improved, and there is also sweat IJ, +,',i, which reduces the propeller excitation force and improves the course-keeping performance of the body.

[Brief explanation of the drawing]

Figures 1 to 3 show a conventional ship. Figure 1 is a side view of the stern, Figure 2 is a vector diagram of the flow velocity on the plane of rotation of the propeller, and Figure 3 is a diagram of the propeller at the point of rotation. FIG. 4 is an explanatory diagram showing the relationship between the rotational direction of propeller blades and the flow velocity, and FIGS. 4 to 6 show a practical example of the present invention. FIG.
fllllllll1h1 of the tail section is a bottom 1nJ diagram of the stern seen from below, and diagram f56 is a vector diagram of the flow velocity in the propeller rotation i1g plane. 1... Stern end, 2... Propeller, 2a... Propeller blade,
3. Propeller 1σ1 rotation, 4. Bupi Bella 1m rotation Jj
Direction, 6... Rough surface forming part, 7... Water line, 8... Propeller axis, 9... Rudder, 10... Hull center line, 11... Numa J waterline, II... From the bottom of the ship to the propeller axis distance. Figure 1 Figure 2/

Claims (1)

[Claims] In a ship equipped with a screw propeller at the stern, in the direction in which the ship is propelled, the screw propeller is 11g L), and the propeller blade is attached to the outer surface of the stern on the side facing one side or the propeller blade. 1. A ship, characterized in that the rl () on the side facing the power is formed in the phase part over a range of approximately 2 ilr of the height from the bottom of the ship to the propeller axis compared to the outer surface of the stern 1" 2.