JPS625834B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for improving the propulsion performance of a ship.

Figures 1 and 2 show the stern of a normal one-shaft, one-rudder ship, and Figures 3 and 4 show the stern of a normal one-shaft, one-rudder ship, and Figures 3 and 4 show the stern section of a normal one-shaft, one-rudder ship. This shows a conventional ship propulsion performance improvement device that applies a rotational flow in the opposite direction to the rotation of the propeller to the flow flowing into the propeller, thereby canceling out the rotational flow behind the propeller and improving propulsion efficiency. The fins mentioned above are generally called reaction fins.

Figures 5 and 6 show a case in which a ring is attached to the outside of the reaction fin to increase the strength of the reaction fin, and Figures 7 and 8 show a case in which a similar reaction fin is attached to the rudder behind the propeller, and a similar reaction fin is attached to the rudder behind the propeller. This shows the case where the propulsion efficiency is improved by eliminating the rotational flow generated at the rear, and FIGS. 9 and 10 show the cross-sectional shape of the reaction and how the direction of the water flow changes accordingly.

Note that Figures 1, 3, 5, and 7 are side views of the hull showing the stern part, Figure 2 is a cross-sectional view of Figure 1, and Figure 4 is a cross-sectional view of Figure 1.
The figure is a sectional view of Fig. 3, Fig. 6 is a sectional view of Fig. 5, Fig. 8 is a sectional view of Fig. 7, Fig. 9 is a sectional view of Fig. 4, and Fig. 10 is a sectional view of Fig. 4. It is a cross-sectional view taken along line XX in Figure 8, and number 1 in the figure indicates the hull;
a is the bottom of the ship, 1b is a cross section of the hull, 2 is a diagram of the cross-sectional shape of the hull, 3 is a propeller, 3a is a propeller boss, 4 is a rudder, 4a is a cross section of the rudder, 5 is an upper rudder support member, 6 is a rudder handle, 7 is the shoe piece, 7a is the cross section of the shoe piece, 8 is the propeller cap, 9 is the propeller shaft,
9a is a cross section of the propeller shaft, 10 is a stern bossing, 10a is a cross section of the stern bossing, 11a is an upper stern frame, 11b is a lower stern frame, 12 is a load water line, 13a, 13b, 13
c, 13d, 13e, 13f, 13g, 13h are reaction fins attached to the front of the propeller,
13b' is the cross-sectional shape of the reaction fin, 14 is the ring, 15b, 15c, 15d, 15f, 15
g, 15h are the reaction fins attached to the rear of the propeller, 15b' is the cross-sectional shape of the reaction fins, 16 is the bulge for attaching the reaction fins to the rudder surface, 18 is the water flow flowing into the reaction fins, 19 indicates the water flow flowing out from the reaction fin.

The above-mentioned reaction fin device as a device for improving ship propulsion performance is achieved by providing a plurality of fins either in front or behind the propeller in a normal one-shaft, one-rudder ship shown in Figures 1 and 2. This improves propulsion efficiency by eliminating the rotational flow that flows behind the propeller and causes loss.

3 and 4 show a case where eight reaction fins 13a to 13h are provided in front of the propeller 3, and each reaction fin 13a to 13h is provided in front of the propeller 3.
13h has one end fixed to the stern bottom sig 10,
The other end is configured in a free cantilever shape.

The cross-sectional shape of these reaction fins 13a to 13h differs depending on the direction of rotation of the propeller, but when the propeller rotates clockwise, the cross-sectional shape 13b' is as shown in FIG. Due to the presence of , the water stream 18 flowing into it becomes a water stream 19 whose direction has changed by θ ₁ and leaves the water stream 19 .

In this way, eight reaction fins 13a to 13h are provided radially in front of the propeller, so that the water flow flowing into the propeller is directed to the propeller 3.
It will have a rotation in the opposite direction to the rotation direction of .

Therefore, by appropriately selecting the magnitude of the rotation of this water stream, the rotation of this water stream can be made to have the same magnitude and the opposite direction as the rotational flow generated by the action of the propeller, As a result, it is possible to prevent rotation from remaining behind the propeller.

By recovering the rotational energy that has flowed to the rear of the propeller in this way, propulsion efficiency is improved.

Incidentally, the larger the number of reaction fins 13a to 13h, the better from the standpoint of creating a rotating flow, but as the number of fins increases, the resistance of the fins also increases, so it is not practical to increase the number too much. Also, attaching the fins to the stern bossing 10 becomes difficult as the number of fins increases.

Therefore, it is common to use a minimum of 4 reaction fins and a maximum of 10 reaction fins, and most commonly to use 6 or 8 reaction fins.

Figures 3 and 4 show reaction fins 13a to 13.
h is fixed to the stern bossing 10 in a cantilevered manner.In such a cantilevered member, the stress is highest at the root, so the structure of the reaction fin is also thinnest at the tip and thickest at the root. configured. For this reason, the fins near the base of the reaction fins become close to each other, making it difficult for water to flow, and as a result, the resistance of the reaction fins increases. In addition, each reaction fin is prone to vibration, and in order to prevent this, the structure of the reaction fin must be made extremely strong, and for this purpose, the reaction fin must be made even thicker. This has the disadvantage of increasing the resistance of the reaction fin.

Also, from a manufacturing perspective, the reaction fin 13a
13h to the stern bossing 10 requires a lot of work.

5 and 6, reaction fins 13a to 13h are designed to compensate for the structural defects of the reaction fins 13a to 13h configured in a cantilevered manner.
A ring 14 is provided on the outside of the reaction fin, and the outer end of the reaction fin is fixed to this ring. By configuring it in this way, the cantilevered structure of the reaction fin can be eliminated and the natural frequency of the reaction fin can be increased to avoid the generation of vibration. Finn 13a~
Since the resistance of the ring 14 is added to the ring 13h, it is not a good idea from the standpoint of improving propulsion efficiency, and the reaction fins 13a to 13h and the stern bottoming 10
There is little improvement in the water flow situation in the areas where the pipes are attached.

The stress at the root of the reaction fin is ring 1
4 directly from the hull, but the structure is still typically thickest at the base and thinnest at the tip, even if the ring 14 is rigidly supported on the hull. ,
The limit is to make the thickness of the reaction fin uniform from the root to the tip.

In some cases, the vertical reaction fins 13a, 13e may be omitted, and the upper and lower stern frames 11a, 11b may be left as they are.

7 and 8 show reaction fins 15b, 15c, 15d on the surface of the rudder 4 behind the propeller 3.
15f, 15g, and 15h are attached, and the rotational flow generated by the action of the propeller 3 is transferred to these reaction fins 15b~15d, 15f~
15h, and the rotational energy is recovered.

In this example, there is no vertical reaction fin, and a rudder 4 is used instead. Since the reaction fins 15b to 15d and 15f to 15h are configured in a cantilevered manner, the stress is highest at the root. For this reason, the structure of the reaction fin is thinnest at the tip and thickest at the base. The bulge 16 on the rudder surface is the reaction fin 15.
b to 15d, 15f, and 15h are provided so that they can be easily attached to the rudder 4.

However, such a reaction fin 1 on the rudder
When 5b to 15d and 15f to 15h are provided, all the various forces acting on the reaction fins are directly transmitted to the rudder, so these forces are applied to the bearings and support members that support the rudder. There are drawbacks such as the need to strengthen the structure and the possibility of damage to the structure.

Furthermore, along with steering, the reaction fin 15
Since the relative positions of b to 15d, 15f to 15h and the propeller 3 change, there is a drawback that the expected effect cannot necessarily be achieved.

The cross-sectional shape of the reaction fin differs depending on the rotation direction of the propeller, but when the propeller 3 is clockwise, the cross-sectional shape 15b' is as shown in FIG. 10, and the propeller wake 18 is as follows. Due to the presence of the reaction fin 15b, the water flows out as a water stream 19 whose direction is changed by _θ2 .

The present invention has a structural disadvantage in that the conventional reaction fin is fixed to the stern bossing, which makes the work difficult, and furthermore, the reaction fins are closely spaced with each other in this vicinity.
Considering that the water flow is obstructed, the mounting structure of the fins has been devised to simplify the work.
It is an object of the present invention to provide a ship propulsion performance improving device that allows smooth flow of water.

Therefore, the ship propulsion performance improving device of the present invention has a ring fixed to the ship's hull, which has a diameter smaller than the diameter of the propeller, in front or behind the propeller of the ship, and a plurality of rings inside and outside of the ring. It is characterized in that the fins are each protruded in the radial direction in the form of a cantilever, and the fins are arranged so as to have an angle of attack with respect to the water flow.

Hereinafter, embodiments of the present invention will be explained with reference to the drawings. Figs. 11 and 12 show the first embodiment, Figs. 13 and 14 show the second embodiment, and Figs. 11 and 13 show the stern part. 12 is a sectional view taken along line XII-XII of FIG. 11, and FIG. 14 is a sectional view taken along line XII--XII of FIG. 13.

Also, among the reference numerals in FIGS. 11 to 14, the same reference numerals as those already described indicate similar parts, and 3a' is a cross section of the propeller boss, 13a', 13
b', 13c', 13d', 13e', 13f', 13g',
1
3h' are reaction fins protruding from the outer surface of the ring 14 in front of the propeller, 15a', 15
b', 15c', 15d', 15e', 15f', 15g',
1
5h' indicates a reaction fin protruding from the outer surface of the ring 14 at the rear of the propeller, and 15a'' indicates a cross section of the reaction fin 15a'.

First, the first embodiment of the present invention will be described. As shown in FIGS. 11 and 12, in this embodiment, eight reaction fins are provided on each of the inner and outer surfaces of the ring 14. The number is usually about 4 to 10, so the selection of the number is the same as in the case of conventional technology.

These reaction fins 13a to 13h;
13a' to 13h' are provided in front of the propeller 3 and are provided radially and cantilevered on both the inner and outer surfaces of a ring 14 having a diameter smaller than that of the propeller 3, and are vertical reaction fins 13a' at the upper part of the outer surface of the ring 14. The ring 14 is fixed to the upper stern frame 11a, the lower vertical reaction fin 13e' and the ring 14 are fixed to the lower stern frame 11b, so that the main hull 1
installed on. In some cases, in addition to the above, vertical reaction fins 13a and 13e on the inner surface of the ring 14 may also be attached to the stern frame 11.
a, 11b.

The reaction fins 13a to 13h provided on the inner surface of the ring 14 are not fixed to the stern bossing 10 but are formed in a cantilever shape, and the reaction fins 13a' to 13h' provided on the outer surface of the ring 14 are also fixed in the vertical direction. Except for the reaction fins 13a' and 13e', the structure is cantilevered. Furthermore, the length of each reaction fin can be reduced to 1/2 or less of the reaction fin of conventional technology, except for the vertical reaction fins 13a' and 13e' on the outer surface of the ring 14, which is significantly advantageous in terms of strength. Even though it has a cantilevered structure, the thickness can be significantly reduced.

Reaction fins 13a to 13h; 13a' to 13 provided on the inner and outer surfaces of the ring 14 as described above.
h' length and thickness, excluding the vertical reaction fins 13a' and 13e' on the outer surface of the ring 14,
Since the resistance can be made significantly smaller than that of the conventional technology, the resistance can be reduced, and thereby the effect of the present propulsion performance improving device can be improved more than that of the conventional technology.

In addition, reaction fins 13a to 13h; 1
3a' to 13h' and the ring 14 are integrally constructed, and the inner ends of the reaction fins 13a to 13h provided on the inner surface of the ring are connected to the stern bossing 10.
Since it is not fixed to the main hull 1, it is easy to attach it to the main hull 1, and the structure of the stern botting 10 can be significantly simpler than that of conventional technology. It does not interfere with

In the second embodiment of the present invention shown in FIGS. 13 and 14, the reaction fin is installed behind the propeller 3 and in front of the rudder 4, and as in the first embodiment, the ring 14 has a smaller diameter than the propeller 3. There are eight reaction fins 15a to 15h; 15a' to 1 radially and cantilevered on the inner and outer surfaces of the
5h' is provided. Reaction Fin 15a~
15h; The number of rings 15a' to 15h' to be attached to the inner and outer surfaces of the ring 14 and the angle of attack relative to the water flow are selected in the same manner as in the conventional technology in which a reaction fin is attached to the rear of the propeller.

These reaction fins 15a to 15h;
15a' to 15h' and the ring 14 are integrally constructed,
Reaction fin 15 provided on the outer surface of the ring 14
The upper part is fixed to the hull 1 and the upper rudder support member 5, and the lower part is fixed to the showpiece 7 via a' and 15e'.

Reaction fins 15a to 15h provided on the inner and outer surfaces of the ring 14; 15a' to 15h' have the same length as the vertical reaction fins 15a', 15h.
Excluding e′, 1/2 of the reaction fin of conventional technology
It is extremely advantageous in terms of strength because it can be reduced to less than
Despite the cantilever configuration, the thickness can be significantly reduced.

The inner ends of the reaction fins 15a to 15h provided on the inner surface of the ring 14 are located outside the radius of the bossing 3a of the propeller 3.

In this embodiment, the reaction fin 1 in the vertical direction
5a to 15e; 15a' to 15e' and the rudder 4 are overlapped, but since the rudder 4 has the same function as the vertical reactions 15a, 15e, 15a', and 15e', the ring vertical reaction fins 15a' on the outer surface that have the function of supporting the
Except for 15e', the inner vertical reaction fins 15a and 15e may be omitted.

According to such a structure, the structure of the rudder and the structure of the shaft and bearings that hold the rudder are simplified, and the structure of the rudder 4 is simplified, and the structure of the shaft and bearings that hold the rudder is simplified, and there is no need to attach the reaction fin to the rudder 4 as in conventional technology. 15
a to 15h; 15a' to 15h' and the ring 14 are integrally constructed and can be attached to the hull as is, making the work simple and easy.

In addition, the lengths and thicknesses of the reaction fins 15a to 15h; 15a' to 15h' provided on the inner and outer surfaces of the ring 14, except for the vertical reaction fins 15a' and 15e' on the outer surface of the ring 14, were changed using conventional technology. Since the resistance can be made significantly smaller than that of the conventional technology, the resistance can also be made smaller, thereby making it possible to improve the effect of the present propulsion performance improving device compared to the conventional technology.

Furthermore, in this embodiment, since there are no reaction fins 15a to 15h near the center of the propeller 3, unlike in the conventional case, the flow near the propeller blade root is not obstructed, and the propeller cap 8 can be attached and detached, and the rear of the propeller shaft 9. The propeller mounting nut (not shown) that screws into the end can be easily attached and detached.
The propeller 3 can also be removed by pulling out the propeller shaft 9 into the hull.

Further, since this device is directly fixed to the hull without using the rudder 4, it can always exhibit its propulsive performance improvement effect regardless of the steering of the rudder 4.

According to the above two embodiments, a ring is disposed in front or behind the propeller, the diameter of the ring is smaller than that of the propeller circle, and radial reaction fins are provided on the inner and outer surfaces of the ring in a cantilevered manner. The following effects can be achieved by providing a protruding structure.

(1) Reduce the length of the reaction fin to 1/ of that of the conventional one.
It can be set to 2 or less.

(2) The thickness of the reaction fin can be significantly reduced even though it is supported like a cantilever.

(3) The structure of the stern bossing is also simpler than the conventional one, and does not obstruct the water flow near the propeller blade root.

(4) As a synergistic effect of the above (1) to (3), it is possible to reduce the size of the reaction fin, reduce costs, reduce water resistance, and improve propulsion performance.

In short, according to the present invention, a ring having a diameter smaller than the diameter of the propeller is fixed to the ship's hull at the front or rear of the propeller of the ship, and a plurality of fins are installed on the inside and outside of the ring, respectively. By protruding in the radial direction like a beam and arranging the above-mentioned fins at an angle of attack with respect to the water flow, all the conventional manufacturing and functional problems have been solved. The present invention is industrially extremely useful because it provides a ship propulsion performance improvement device that greatly improves ship propulsion performance while reducing costs.

[Brief explanation of the drawing]

Figures 1 and 2 show the stern of a normal one-shaft, one-rudder vessel, with Figure 1 being a side view, Figure 2 being a cross-sectional view taken along the - line in Figure 1, and Figure 3 being a cross-sectional view taken along the - line in Figure 1. , 4 shows a conventional ship propulsion performance improvement device.
The figure is a side view, Figure 4 is a cross-sectional view taken along the - line in Figure 3, and Figures 5 and 6 show other examples of conventional ship propulsion performance improvement devices. The side view, FIG. 6 is a cross-sectional view taken along the line - in FIG. 5, and FIGS. Figure 8 is a cross-sectional view taken along line - in Figure 7, Figure 9 is a cross-sectional view taken along line - in Figure 4, and Figure 10 is a cross-sectional view taken along line - in Figure 8. 11 and 12 show a ship propulsion performance improvement device as a first embodiment of the present invention.
The figure is a side view, FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. 11, and FIGS. 13 and 14 show a ship propulsion performance improvement device as a second embodiment of the present invention. , FIG. 13 is a side view thereof, and FIG. 14 is a cross-sectional view taken along the - line in FIG. 13. 1...Hull, 1a...Bottom, 1b...Hull cross section, 3...Propeller, 3a...Propeller boss, 3
a'... Cross section of propeller boss, 4... Rudder, 5... Upper rudder support member, 6... Rudder handle, 7... Show piece, 7a... Cross section of show piece, 8... Propeller cap, 9... Propeller Shaft, 9a... Cross section of propeller shaft, 10... Stern botting, 10a...
...Cross section of the stern bossing, 11a... Upper stern frame, 11b... Lower stern frame,
12... Load waterline, 13a, 13b, 13c,
13d, 13e, 13f, 13g, 13h; 13
a', 13b', 13c', 13d', 13e', 13f',
1
3g', 13h'...Reaction fin in front of propeller, 14...Ring, 15a, 15b, 15
c, 15d, 15e, 15f, 15g, 15h;
15a', 15b', 15c', 15d', 15e', 15
f', 15g', 15h'... Reaction fin at the rear of the propeller, 15a''... Reaction fin 15
Cross section of a′.

Claims (1)

[Claims] 1. A ring having a diameter smaller than the diameter of the propeller is fixed to the ship's hull at the front or rear of the ship's propeller, and a plurality of fins are cantilevered in the radial direction on the inside and outside of the ring. What is claimed is: 1. A ship propulsion performance improving device, characterized in that the fins are protruding and arranged so as to have an angle of attack with respect to the water flow.