JP5372977B2 - Composite fin - Google Patents

Description

  The present invention relates to a composite fin that is attached to the stern of a ship.

  Conventionally, as this type of stern fin structure, a rectifying fin is attached to both sides of a hull outer plate in front of a stern propeller, and the applicant of the present application has already been disclosed in Japanese Patent Application Laid-Open No. 2004-42881. The one disclosed in the gazette is proposed.

  The one disclosed in Japanese Patent Application Laid-Open No. 2004-42881 relates to the invention name “asymmetrical stern fin structure” and “cancels the specific resistance of the fin, reduces the hull resistance, and at the same time generates an untargeted flow to the propeller. "To provide an asymmetrical stern fin structure with improved self-propelled elements" (see paragraph number 0008 of the same gazette), "one surface is configured to be a flat surface and the other surface is a hull mounting portion. The stern fins having a cross-sectional shape whose thickness decreases from the open end side to the open end side, the flat surfaces of the stern fins are arranged on both the left and right sides of the propeller in the rotation direction, and the side surfaces of the hull mounting portion of the stern fins The elevation angle is set to a predetermined value, the rear end height of the stern fin is arranged in a range of 60 to 70% of the propeller radius, and the rear end of the stern fin is a position of about 0.5 station. With the configuration of “arranged in the vicinity” (see the description of claim 1 of the publication), “(1) the propeller thrust is assisted, and the hull resistance value and the self-propelled element are improved by a predetermined value. (2) Among the stern fin structures, the structure in which the starboard stern fin is retracted by a predetermined position and the left and right positions are shifted is the thrust reduction coefficient of the self-propelled element. The effect is “improved” and the like (see paragraph number 0032 of the same gazette specification).

FIG. 5 is a starboard side view (FIG. 1 attached to the publication) showing an asymmetric stern fin structure according to the first embodiment disclosed in the publication.
In FIG. 5, 101 is an asymmetric stern fin structure, 103 is a ship, 105 is a stern, 107a is a stern fin, 109 is a propeller, 111 is a rudder, AP is a stern perpendicular (Aft. Perpendicular), ST The stations L1 and L2 are fluids that flow on the flat surface side of the stern fin 107a.

  As shown in FIG. 5, the asymmetric stern fin structure 101 disclosed in Japanese Patent Application Laid-Open No. 2004-42881 is configured so that one surface is a flat surface and the other surface is thicker from the hull mounting portion toward the open end side. The stern fins 107a and 107b having a reduced cross-sectional shape are arranged on both the left and right sides with the flat surfaces facing the rotation direction of the propeller 109, and the side elevation angle of the stern fins 107a and 107b is 5 degrees. -16 degrees upward angle, the rear end height of the stern fins 107a, 107b is arranged in the range of 60-70% of the propeller radius, and the rear end of the stern fin 107a (107b) is substantially The front end of the stern fin 107a (107b) is arranged in the vicinity of a predetermined position behind the approximately 1.0 station near the position of 0.5 station.

  As described above, in the asymmetric stern fin disclosed in Japanese Patent Application Laid-Open No. 2004-42881, the optimum mounting position and shape differ depending on the hull form, but in many cases, the rearward is inclined upward. The longer the fins, the greater the effect of reducing the resistance by rectifying the flow around the hull, but at the same time the specific resistance of the fins increases, so that the effect of reducing the resistance of the fins themselves cannot be obtained sufficiently There is.

JP 2004-42881 A

  An object of the present invention is to provide a composite fin that improves the flow flowing into the asymmetric stern fin and reduces the resistance of the asymmetric stern fin.

In order to achieve the above object, in the invention according to claim 1 of the present application, in the composite fin, one surface is configured to be a flat surface, and the other surface is decreased from the hull mounting portion toward the open end side to reduce the thickness. The stern fins having a cross-sectional shape are arranged on both right and left sides with the flat surfaces facing the rotation direction of the propeller, and the side elevation angle of the hull mounting portion of the stern fins is set to a predetermined value. In the asymmetric stern fin structure in which the rear end height is arranged in a range of 60 to 70% of the propeller radius, and the rear end of the stern fin is arranged in the vicinity of the position of about 0.5 station, The position of the rear end substantially coincides with the position of the front end of the asymmetric stern fin, or is 1 frame ahead and the height of the position 1/5 to 1/3 from the rear end of the asymmetric stern fin. Trailing edge The height position of the front end is about 10% of the length (L) of the asymmetric stern fin from the front end of the asymmetric stern fin on the extension line of the flat surface (long side) of the asymmetric stern fin. A length of about 60 to 70% of the length (L) of the asymmetric stern fin with a backward upward inclination at a predetermined position in the range of the height lowered in the range of (0 to 1/10) × L ((0.6 to 0.7) × L) and a single plate having a width of about 60 to 70% of the width (B) of the asymmetric stern fin and a sub plate supporting the same, the sub plate Is attached to the upper or lower surface of the veneer, and when viewed from the ship side , small fins with a shape of a regular trapezoid whose upper part is smaller than the lower part are perpendicular to both sides of the hull whose ship width is approximately 32.26 m. It is installed.

Since this invention is comprised as mentioned above, there exists an effect described below.
(1) By controlling the flow flowing into the asymmetric stern fin with a small front fin and reducing the resistance, the propulsion performance can be improved by about 1.5 to 2% compared to the case of using the asymmetric stern fin alone. It has the effect. (See Figure 3)

FIG. 1A is a port side arrangement view of the composite fin according to the first embodiment, and FIG. 1B is a starboard side arrangement view thereof. FIG. 2 is a layout view of the composite fin according to the first embodiment in the AA cross section and the BB cross section shown in FIG. (A) A graph of a water tank test result when equipped with the composite fin according to the first embodiment, (b) a graph of horsepower reduction effect when equipped with the composite fin according to the first embodiment, (A) Conceptual diagram in the case of asymmetric stern fin alone, (b) Conceptual diagram in the case of having the composite fin according to the first embodiment, It is a starboard side view (the gazette attachment figure 1) which shows the asymmetric stern fin structure which concerns on 1st Embodiment disclosed by Unexamined-Japanese-Patent No. 2004-42881.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A detailed description will be given based on drawings showing an embodiment as a mode for carrying out a composite fin according to the present invention.

  FIGS. 1A and 1B are views showing Example 1 of a composite fin, which is an example of a mode for carrying out the composite fin according to the present invention, of which FIG. FIG. 2B is a port side arrangement diagram of the composite fin 1b according to the first embodiment, and FIG. 2B is a starboard side arrangement diagram (corresponding to FIG. 5). FIG. FIG. 3 is a layout view of the front fins 1a and 1b according to the first embodiment in the B cross section, and is a view seen from the rear of the hull.

  In FIGS. 1A and 1B, reference numerals 1a and 1b denote composite fins according to the first embodiment, of which 1a is a composite fin according to the first embodiment arranged on the starboard and 1b is a port fin. It is a compound type fin concerning Example 1 arranged. In FIGS. 1A and 1B, 107a and 107b are asymmetric stern fins disclosed in Japanese Patent Application Laid-Open No. 2004-42881, and AA is a cross-sectional view in the transverse direction of the hull of the asymmetric stern fins 107a and 107b. Lines BB are cross sections along the hull of the front fins 1a and 1b of the composite fin according to the present invention, and the other reference numerals are the same as those shown in FIG. Show.

  In FIG. 2, 107a and 107b are asymmetric stern fins disclosed in Japanese Patent Application Laid-Open No. 2004-42881, 1a and 1b are composite fins according to the first embodiment, and 2a and 2b are the first embodiment. The steel plate single plates 3a and 3b constituting the composite fin according to the above are sub-plates for supporting the single plates 2a and 2b.

  As shown in FIGS. 1 (a) and 1 (b), the front fins 1a and 1b of the composite fin according to the first embodiment have small fins in a predetermined shape and a predetermined position in front of the asymmetric stern fins 107a and 107b. Attached and combined with the asymmetric stern fins 107a and 107b are combined fins 1a and 1b. That is, as shown in FIGS. 1 (a) and 1 (b), a small-sized fin having a predetermined shape inclined upward and backward is attached in front of the asymmetric stern fins 107a and 107b, and the asymmetric stern fins 107a and 107b are attached. By accelerating the flow that flows into the stern, the drag acting on the asymmetric stern fins 107a and 107b (lifting force in the direction opposite to the traveling direction) is reduced.

  Moreover, the front fins 1a and 1b of the composite fin according to the first embodiment are composed of steel plate veneers 2a and 2b and sub plates 3a and 3b supporting the veneers, and as shown in FIG. Are attached by welding so as to be substantially perpendicular to the surface of the hull 103.

  Further, both the front fins 1a and 1b of the composite fin according to the first embodiment are structured such that the sub-plates 3a and 3b are attached to the upper surfaces of the single plates 2a and 2b, and when viewed from the ship side, the upper portion is the lower portion. It exhibits a smaller trapezoidal shape. In this point, the asymmetric stern fins 107a and 107b have the asymmetric stern fins 107a arranged on the starboard in relation to the rotation direction of the propeller 109, as shown in FIGS. 1 (a) and 1 (b). Has a trapezoidal cross section shorter than the lower bottom, and the asymmetrical stern fin 107b disposed on the port side is different from an inverted trapezoidal shape in which the upper bottom is longer than the lower bottom.

  As shown in FIGS. 1 (a) and 1 (b), the front fins 1a and 1b of the composite fin according to the first embodiment are arranged in front of the asymmetric stern fins 107a and 107b and the length of the asymmetric stern fins 107a and 107b. About 60 to 70% of the length (L) ((0.6 to 0.7) × L), and about 60 to 70% of the width (B) of the asymmetric stern fins 107a and 107b. The front fins 1a and 1b of the composite fin according to the first embodiment are attached with an inclination to the rear upward.

  The inclination is such that the positions of the rear ends of the front fins 1a and 1b of the composite fin according to the first embodiment substantially coincide with the front end positions of the asymmetric stern fins 107a and 107b. 107a, 107b from the front end height position of the asymmetric stern fins 107a, 107b from the rear end of the position of 1 / 4-1 / 3 of the front fins 1a, 1b of the composite fin according to the first embodiment The rear end height position. That is, the mounting position in the front-rear direction of the rear ends of the front fins 1a and 1b of the composite fin according to the first embodiment is aligned with the front ends of the asymmetric stern fins 107a and 107b. The rear end height of the front fins 1a, 1b is a position (1/3 to 1/4 lower than the rear end height of the asymmetric stern fins 107a, 107b from the rear end of the asymmetric stern fins 107a, 107b ( (1/3 to 1/4) × L).

  Further, the height of the front ends of the front fins 1a and 1b of the composite fin according to the first embodiment is such that the flat surfaces (long sides) of the asymmetric stern fins 107a and 107b from the front ends of the asymmetric stern fins 107a and 107b. On the extension line, the height range ((0 to 1/10) × L) is lowered in the range of about 10% of the length (L) of the asymmetric stern fin from the extension line.

  Thus, the length and width of the front fins 1a and 1b of the composite fin according to the first embodiment are about 60 to 70% of the length (L) of the asymmetric stern fins 107a and 107b and about 60 to The reason why the width is 70% is that each fin has a specific resistance, and if it is equal to or larger than the asymmetrical stern fins 107a and 107b arranged at the rear, it is almost equal to the asymmetrical stern fins 107a and 107b. Since the equivalent specific resistance acts on the front fin, the resistance exceeds the effect of reducing the specific resistance of the asymmetric stern fins 107a and 107b. On the other hand, if it is too small, the effect of accelerating while changing the flow flowing into the asymmetric stern fins 107a and 107b upward cannot be obtained sufficiently. Therefore, the optimum length and width were set to about 60 to 70% length (L) and about 60 to 70% width by the water tank test.

  In addition, the end of the fin of this type is configured so that the positions of the rear ends of the front fins 1a and 1b of the composite fin according to the first embodiment coincide with the front ends of the asymmetric stern fins 107a and 107b. This is because it is more convenient to work with the frame position of the hull, which is more convenient in terms of work, and the rear end positions of the front fins 1a and 1b of the composite type fins according to the first embodiment arranged in the front are asymmetric. This is because if the stern fins 107a and 107b are arranged behind the front end positions, the distance between the fins becomes narrow, and as a result, the flow of water is hindered and the resistance may increase.

  However, according to the subsequent water tank test, the position of the rear end of the front fins 1a and 1b of the composite fin according to the first embodiment disposed forward is about one frame from the front end of the asymmetric stern fins 107a and 107b. Even if it was arranged in the front, the same effect was obtained. Therefore, the arrangement relationship of this portion is limited to that the rear end positions of the front fins 1a and 1b of the composite fin according to the first embodiment arranged in front are matched with the front end positions of the asymmetric stern fins 107a and 107b. However, the rear end positions of the front fins 1a and 1b of the composite fin according to the first embodiment are aligned with the front end positions of the asymmetric stern fins 107a and 107b, or are arranged one frame ahead of the positions. It may be made to be done.

  Further, the height of the rear ends of the front fins 1a and 1b of the composite fin according to the first embodiment is located at a height of 1/4 to 1/3 length (L) from the rear ends of the asymmetric stern fins 107a and 107b. Basically, as described above, even if the rear ends of the front fins 1a, 1b of the composite fin according to the first embodiment are made higher than the rear ends of the asymmetric stern fins 107a, 107b, While the flow flowing into the asymmetric stern fins 107a and 107b does not change so much, there is a concern that the resistance increases due to the increase of the front fins 1a and 1b of the composite fin according to the first embodiment arranged in the front. Because there is.

  In the subsequent water tank test, the same effect can be obtained even if the front fins 1a and 1b of the composite fin according to the first embodiment are arranged at the height of about 1/5 × L. As a result, the rear end height is 1/5 to 1/3 length from the rear end of the asymmetrical stern fins 107a and 107b ((1/5 to 1/3). The height in (L) may be sufficient.

  Further, the height of the front ends of the front fins 1a and 1b of the composite fin according to the first embodiment is from the front ends of the asymmetric stern fins 107a and 107b on the extended line of the long sides of the asymmetric stern fins 107a and 107b. The height range ((0 to 1/10) × L) lowered from the extension line in the range of about 10% of the length (L) of the asymmetric stern fin is set in the forward direction. When the upward angle behind the front fins 1a and 1b of the composite fin according to Example 1 is made smaller than that of the asymmetric stern fins 107a and 107b, acceleration is performed while changing the flow flowing into the asymmetric stern fins 107a and 107b upward. The effect cannot be obtained sufficiently.

  However, depending on the angle of the asymmetric stern fins 107a and 107b, this range does not necessarily fall within this range. Therefore, this condition is “rearward of the front fins 1a and 1b of the composite fin according to the first embodiment disposed in the front. The upward angle is equal to or greater than that of the asymmetric stern fins 107a and 107b.

(Water tank test)
The water tank test of the front fins 1a and 1b of the composite fin according to the first embodiment was performed. The test was conducted in a water tank installed at the applicant company using a model, and the correlation water tank test result of the Froude number (Fn) and the residual resistance coefficient (rR) and the horsepower reduction effect of the composite fin according to the first embodiment were verified. did.

  FIG. 3A is a graph of a water tank test result showing a correlation between the hull fluid number (Fn) and the residual resistance coefficient (rR) when the composite fin according to the first embodiment is equipped. ) Is a graph of the horsepower reduction effect between horsepower and speed when the composite fin according to the first embodiment is installed. In FIG. 3 (a), the solid line is a graph showing the correlation between the hull fluid number (Fn) and the residual resistance coefficient (rR) when the asymmetric stern fins 107a and 107b are independently provided. 3 is a graph showing the correlation between the hull fluid number (Fn) and the residual resistance coefficient (rR) when the front fins 1a and 1b of the composite fin according to the first embodiment are installed in front of the fins 107a and 107b. In (b), the wavy line is a graph showing the speed-horsepower when the asymmetric stern fin is provided alone, and the solid line is the front fin of the composite fin according to the first embodiment in front of the asymmetric stern fins 107a and 107b. It is a graph which shows speed-horsepower when 1a and 1b are equipped.

  As can be seen from FIG. 3 (a), when the front fins 1a and 1b of the composite fin according to the first embodiment are equipped in front of the asymmetric stern fins 107a and 107b, compared to the case where the front fins 1a and 1b are not equipped, The residual resistance coefficient (rR) is high for any fluid number, and as can be seen from FIG. 3B, the composite fin according to the first embodiment is placed in front of the asymmetric stern fins 107a and 107b. It can be seen that when the front fins 1a and 1b are equipped, the horsepower reduction effect is found and the propulsion performance is improved by about 1.5 to 2%, compared with the case where the front fins 1a and 1b are not equipped.

  4A and 4B are diagrams illustrating the operation principle of the composite fin according to the first embodiment. FIG. 4A illustrates the principle when an asymmetric stern fin is provided alone, and FIG. 4B illustrates the asymmetric stern fin. It is a principle figure at the time of equip | installing the front fins 1a and 1b of the composite type fin which concerns on the present Example 1 ahead of 107a and 107b.

  4 (a) and 4 (b), the thick solid lines α, β, γ, and δ are respectively decelerated by the flow α decelerated by the asymmetric stern fin, the flow β accelerated by the asymmetric stern fin, and the forward fin. The flow γ and the flow δ accelerated by the forward fin are shown, and the pressure P3 below the asymmetric stern fin is decreased by the flow β accelerated by the asymmetric stern fin. When the pressure P1 increases, lift is generated in the asymmetric stern fin, and the forward component of the lift becomes the specific resistance F1 applied to the asymmetric stern fin. Further, due to the flow δ accelerated by the front fin, the pressure P2 above the asymmetric stern fin decreases, and the forward direction component of lift generated in the asymmetric stern fin, that is, the specific resistance F2 applied to the asymmetric stern fin is greater than the specific resistance F1. Is also reduced.

That is, when the front fins 1a and 1b of the composite fin according to the first embodiment are installed in front of the asymmetric stern fins 107a and 107b, the resistance by the front fins 1a and 1b of the composite fin according to the first embodiment. The amount of resistance decrease related to the asymmetric stern fins 107a and 107b becomes larger than the increase amount, and the resistance is reduced as a whole.

  The present invention can be arranged on a hull having an asymmetric stern fin to increase the effect.

1a, 1b Front fins 2a, 2b Single plate 3a, 3b Sub plate α Flow decelerated by asymmetric stern fin β Flow accelerated by asymmetric stern fin γ Flow decelerated by front fin δ Flow accelerated by front fin 101 Asymmetric stern fin structure 103 Hull 107a, 107b Asymmetric stern fin 109 Propeller F1, F2 Resistance P1, P2, P3 Pressure

Claims (1)

A stern fin with one surface configured as a flat surface and the other surface configured to reduce in thickness from the hull mounting part toward the open end, and the flat surface facing the propeller rotation direction Each of the stern fins, a side elevation angle of a hull mounting portion of the stern fin is set to a predetermined value, a rear end height of the stern fin is disposed in a range of 60 to 70% of a propeller radius, and the stern In the asymmetric stern fin structure in which the rear end of the fin is arranged near the position of about 0.5 station ,
The position of the rear end in front of each stern fin substantially coincides with the position of the front end of the asymmetric stern fin, or is one frame forward and 1/5 to 1/3 from the rear end of the asymmetric stern fin. And the height position of the front end is the length of the asymmetric stern fin from the front end of the asymmetric stern fin on the extension line of the flat surface (long side) of the asymmetric stern fin. About the length (L) of the asymmetrical stern fin having a backward upward slope at a predetermined position in the range of height ((0 to 1/10) × L) that falls within a range of about 10% of (L) A single plate having a length of 60-70% ((0.6-0.7) × L) and a width of about 60-70% of the width (B) of the asymmetric stern fin and a sub-plate for supporting the same The sub-plate is attached to the upper surface or the lower surface of the veneer and is viewed from the ship side. , Composite fins, characterized in that the upper breadth small fin shape exhibiting a positive trapezoidal shape smaller than the lower is mounted vertically on both broadside approximately 32.26m equivalent hull.

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