JP6292551B2 - Ship equipped with torsion rudder and torsion rudder - Google Patents

Description

  The present invention relates to a torsion rudder for a ship to be mounted on a stern of a hull, and a ship equipped with a torsion rudder.

As shown in FIG. 8, in an asymmetrical stern or twin-skeg type ship, an asymmetrical flow is formed on the left and right sides of the skeg, and a flow with different asymmetry is formed in the height direction. At a height where the propeller surface is at this height, a part of the asymmetric flow becomes a counter flow in the propeller rotation direction due to the operation of the propeller, thereby recovering energy loss created by the asymmetric flow and improving transportation efficiency. Has contributed. However, the asymmetrical flow that cannot be recovered by the propeller and the flow that passes through the propeller surface are not recovered and flow away to the rear of the rudder, resulting in energy loss.
By the way, Patent Document 1 discloses a rudder that is bent as if it has a ridge line at the lower end portion of a ladder horn and has a lower half inclined in a hull whose rear edge is curved from the center surface (upper left column of Japanese Patent Publication No. 3). .
Patent Document 2 discloses a ship provided with at least one twisted rudder plate (paragraph number (0012)).
In Patent Document 3, the rudder leading edge is twisted in the direction opposite to the propeller rotation direction, and the twist amount is partially twisted in the height direction of the shape where the twist amount is maximized at a substantially middle position below and above. A rudder having
Patent Document 4 discloses a reaction rudder that is twisted in the opposite directions above and below the center height position of the propeller shaft.
Patent Document 5 discloses a pair of left and right rudders that incline outward in the hull width direction downward in a biaxial ship.

JP 59-137294 A Special table 2010-505683 Microfilm of Japanese Utility Model No. 59-91952 (Japanese Utility Model Application No. 61-7500) Microfilm of Japanese Utility Model No. 59-112753 (Japanese Utility Model Application No. 61-27798) JP 2012-35785 A

However, in the rudder in Patent Document 1, the rudder's cross-sectional shape is not a wing shape, and the rudder's rotation axis is positioned on the propeller shaft surface so as to correspond to the asymmetrical flow at the stern part formed by the hull shape of the ship. In addition, the twist angle of the airfoil is not continuously changed in the height direction of the rudder.
Moreover, the rudder in patent document 2 is on condition that the rotating screw is not arrange | positioned in the front part of a rudder (paragraph number (0012)).
The rudder in Patent Document 3 is an S-type reaction rudder in which the upper side and the lower side are twisted in the opposite directions with respect to Propellerabos.
Further, the rudder in Patent Document 4 is twisted to the maximum in the vicinity of the propeller shaft and is twisted in the opposite directions vertically.
In addition, the rudder in Patent Document 5 is such that the pair of left and right rudder is inclined, and the rotation axis of the rudder is propeller shaft surface so as to correspond to the asymmetric flow at the stern part formed by the hull shape of the ship. In addition, the airfoil twist angle is not continuously changed in the rudder height direction.

  Therefore, the present invention recovers the energy loss of the asymmetric flow that could not be recovered by the propeller and the energy loss of the flow passing through the propeller surface as lift created by the cross section of the rudder blade, and can obtain the maximum transport efficiency as the entire propulsion system An object is to provide a torsional rudder and a ship equipped with a torsional rudder.

In a torsional rudder for a ship corresponding to the present invention as set forth in claim 1, the rudder is attached to a stern part behind a propeller of a ship, and a rotation axis for rotating the rudder is positioned on a virtual vertical plane passing through the propeller axis. The cross-sectional shape of the rudder is a wing shape, and the torsional angle of the wing shape with respect to the virtual vertical plane is continuous in the height direction of the rudder on either the left or right side of the virtual vertical plane so as to correspond to the asymmetric flow at the stern. And the wing trailing edge of the rudder is gradually separated from the virtual vertical plane toward the upper end . According to the first aspect of the present invention, the lift is generated by using the asymmetric flow at the stern part, so that the resistance reduction and the thrust reduction coefficient are improved, and the effective wake is improved by the improvement of the exclusion effect by the rudder. The rate can be improved. In addition, energy loss due to the flow passing over the propeller surface above the propeller can be recovered as lift.

The present invention according to claim 2 is characterized in that the torsion angle is formed by twisting the airfoil about the rotation axis. According to the second aspect of the present invention, the design of the rudder is facilitated.

The present invention according to claim 3 is characterized in that the airfoil has a camber. According to the third aspect of the present invention, not only a symmetrical wing-type rudder but also an asymmetric wing-type rudder can be applied, and a larger lift can be obtained.

The present invention according to claim 4 is characterized in that the camber becomes larger toward the upper side of the rudder. According to the present invention described in claim 4 , by increasing the camber, it is possible to generate more lift due to the flow passing over the propeller surface above the propeller, and to improve the elimination effect by the rudder.

The present invention according to claim 5 is characterized in that the angle formed by the blade trailing edge with respect to the virtual vertical plane is more than 0 ° and not more than 12 °. According to the fifth aspect of the present invention, the resistance reduction and the thrust reduction coefficient can be improved, and the effective wake ratio can be reliably improved.

In a torsional rudder for a ship corresponding to the present invention as set forth in claim 6, the rudder is attached to a stern part behind the propeller of the ship, and a rotation axis for rotating the rudder is positioned on a virtual vertical plane passing through the propeller axis. The cross-sectional shape of the rudder is a wing shape, and the torsional angle of the wing shape with respect to the virtual vertical plane is continuous in the height direction of the rudder on either the left or right side of the virtual vertical plane so as to correspond to the asymmetric flow at the stern. The airfoil has a camber, and the camber becomes larger toward the upper side of the rudder. According to the sixth aspect of the present invention, the lift is generated by utilizing the asymmetric flow at the stern part, so that the resistance reduction and the thrust reduction coefficient are improved, and the effective wake is improved by the improvement of the exclusion effect by the rudder. The rate can be improved. Moreover, it can be applied not only to a symmetrical airfoil rudder but also to an asymmetric airfoil rudder, and a larger lift can be obtained. Further, by increasing the camber, it is possible to generate more lift due to the flow passing over the propeller surface above the propeller, and to improve the elimination effect by the rudder.

The present invention according to claim 7 is characterized in that the angle formed by the trailing edge of the rudder blade with respect to the virtual vertical plane is more than 0 ° and not more than 12 °. According to the seventh aspect of the present invention, the resistance reduction and the thrust reduction coefficient can be improved, and the effective wake ratio can be reliably improved.

The present invention is claimed in claim 8, a sectional shape different from the airfoil in the lower portion of the airfoil and the steering at the top of the rudder, the airfoil cross sectional shape at the bottom, until the cross-sectional shape of the airfoil at the top, height A shape that smoothly converges in a direction. According to the eighth aspect of the present invention, it is possible to effectively generate lift with respect to the asymmetrical flow in the height direction formed by the hull shape of the ship, and to improve the elimination effect by the rudder.

The present invention according to claim 9 is characterized in that the cross-sectional shape of the airfoil at the lower portion of the rudder is a symmetrical airfoil. According to the present invention as set forth in claim 9 , at the lower part of the rudder where the flow asymmetry is not large, energy loss due to the flow after the propeller can be recovered with a symmetric wing shape.

A ship equipped with a ship twist rudder corresponding to the present invention according to claim 10 is equipped with a ship twist rudder. According to the tenth aspect of the present invention, it is possible to provide a ship that can improve the resistance reduction and the thrust reduction coefficient by the ship torsion rudder and improve the effective wake ratio.

The present invention according to claim 11 is characterized in that the ship is a stern catamaran type ship. According to the eleventh aspect of the present invention, in a stern catamaran type ship, the flow is asymmetrical in the left and right directions and the asymmetry is different in the height direction. Thus, the resistance reduction and the thrust reduction coefficient are improved, and the effect of improving the effective wake ratio is high.

The present invention according to claim 12 is characterized in that the stern catamaran vessel has a skeg. According to the twelfth aspect of the present invention, since the flow asymmetry is large between the left and right sides of the skeg, the resistance reduction and the thrust reduction coefficient are improved by the torsional rudder for a ship, and the effect of improving the effective wake ratio is high.

The present invention according to claim 13 is characterized in that the propeller is attached to the rear of the skeg. According to the present invention as set forth in claim 13, there is provided a ship capable of improving the propeller efficiency ratio, further improving the drag reduction coefficient and the thrust reduction coefficient by the rear ship twisted rudder, and improving the effective wake ratio. it can.

  According to the torsional rudder for a ship of the present invention, the lift is generated by utilizing an asymmetric flow at the stern part to improve the resistance reduction and the thrust reduction coefficient, and the effective wake ratio due to the improvement of the exclusion effect by the rudder. Can be improved.

  Further, when the trailing edge of the rudder blade is gradually separated from the virtual vertical surface toward the upper end, energy loss due to the flow passing over the propeller surface above the propeller can be recovered as lift.

  Further, when the torsion angle is formed by twisting the airfoil around the rotation axis, the rudder can be easily designed.

  Further, when the airfoil has a camber, it can be applied not only to a symmetrical airfoil rudder but also to an asymmetric airfoil rudder, and a larger lift can be obtained.

  Further, when the camber becomes larger toward the upper side of the rudder, by increasing the camber, it is possible to generate more lift due to the flow passing over the propeller surface above the propeller and to improve the elimination effect by the rudder.

  Further, when the angle formed by the blade trailing edge with respect to the virtual vertical plane is greater than 0 ° and equal to or less than 12 °, the resistance reduction and the thrust reduction coefficient can be improved, and the effective wake ratio can be reliably improved.

  In addition, the airfoil at the top of the rudder and the airfoil at the bottom of the rudder have different cross-sectional shapes, and the shape that smoothly converges in the height direction from the cross-sectional shape of the airfoil at the bottom to the cross-sectional shape of the airfoil at the top In this case, it is possible to effectively generate lift with respect to the asymmetrical flow in the height direction formed by the hull shape of the ship and to improve the elimination effect by the rudder.

  In addition, when the cross-sectional shape of the airfoil at the lower part of the rudder is a symmetric airfoil, energy loss due to the flow after the propeller can be recovered at the lower part of the rudder where the flow asymmetry is not large. it can.

  According to the ship equipped with the torsional rudder for a ship of the present invention, it is possible to provide a ship that can improve the resistance reduction and the thrust reduction coefficient by the torsional rudder for the ship and improve the effective wake ratio.

  In addition, when the ship is a stern catamaran vessel, the stern catamaran vessel has a flow that is asymmetrical in both the left and right sides depending on the shape of the hull, and the asymmetrical flow in the height direction is also different. The effect of improving the effective wake ratio by reducing the resistance reduction and the thrust reduction coefficient by the torsional rudder is high.

  In addition, when the stern catamaran vessel has a skeg, the flow asymmetry is large on the left and right of the skeg, so the resistance reduction and thrust reduction coefficient are improved by the torsion rudder for the vessel, and the effective wake ratio is improved. High effect.

  In addition, when the propeller is attached to the rear of the skeg, the propeller efficiency ratio is improved, and further, the vessel can improve the effective wake ratio by improving the drag reduction coefficient and the thrust reduction coefficient by the rear vessel torsional rudder. Can provide.

The principal part perspective view of the ship which shows the state which attached the twisted rudder for ships by one Embodiment of this invention. The principal part front view which shows the state which looked forward at the ship from back Side view of the main part of the ship Explanatory drawing showing the structure of the torsion rudder for the ship Explanatory drawing which shows the structure of the torsion rudder for ships by other embodiment of this invention. FIG. 3 is an enlarged view of a main part of FIG. 2, and shows a torsion rudder for a ship when the propeller rotates inward in a biaxial stern catamaran type ship. Characteristic diagram showing the effect of the torsional rudder for a ship according to the present embodiment with respect to a normal rudder from an aquarium experiment Explanatory diagram showing asymmetric flow in a twin-skeg ship

A marine torsion rudder according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a main part of the ship showing a state where the torsion rudder for the ship is attached, FIG. 2 is a front view of the main part showing a state of the ship as viewed from the rear, and FIG. 3 is a side view of the main part of the ship. It is. Although this embodiment will be described using a stern catamaran type vessel, the torsion rudder for this vessel is a single-hull type vessel in which the shape of the hull forms an asymmetric flow at the stern portion 2 like an asymmetric stern. It can also be applied to.
In particular, as shown in FIG. 1, the torsion rudder 10 for a ship according to the present embodiment is attached to the rear of a propeller 3 attached to the stern part 2 of the hull 1.

  Further, as shown in FIGS. 2 and 3, the rudder rotation shaft 11 for rotating the marine vessel torsion rudder 10 is positioned on a virtual vertical plane V passing through the propeller shaft 3x. Note that the center of the rotating shaft 11 and the center of the propeller shaft 3x do not have to be completely coincident with each other as long as a part of the rotating shaft 11 overlaps the diameter of the propeller shaft 3x. That is, the virtual vertical plane V only needs to be positioned within the diameter of the propeller shaft 3x, and at least a part of the rotation shaft 11 only needs to be positioned with respect to the virtual vertical plane V.

FIG. 4 is an explanatory view showing the structure of the torsion rudder for the ship.
4 (a) is an enlarged view of the main part of FIG. 3, and FIG. 4 (b) shows the cross-sectional shape and twist of the ship's torsional wing shape at the position shown in FIG. 4 (a). (c) has shown the wing | wing trailing edge with respect to the rotating shaft of the torsion rudder for ships in the position shown to Fig.4 (a).

The torsion rudder 10 for ships has a cross-sectional shape of the rudder as a wing shape, and in particular, a twist angle with respect to the virtual vertical plane V of the rudder wing shape so as to correspond to the asymmetric flow in the stern portion 2 formed by the ship hull shape. θ continuously changes in the height direction of the rudder on either the left or right side of the virtual vertical plane V.
The wing trailing edge 10r of the marine torsion rudder 10 has a portion that is not separated from the virtual vertical plane V at least in the lower part of the rudder, and gradually separates from the virtual vertical plane V toward the upper end.
By gradually separating the blade trailing edge 10r from the virtual vertical plane V, it is possible to accurately cope with an asymmetric flow in which the asymmetry gradually increases toward the upper end of the marine vessel rudder rudder 10.
The torsion rudder 10 for a ship forms a torsion angle θ by twisting the airfoil about the rotation shaft 11 in the upper part.
The angle δ formed by the blade trailing edge 10r with respect to the virtual vertical plane V is greater than 0 ° and not greater than 12 °. As shown in the present embodiment, when the cross-sectional shape of the airfoil is a symmetric airfoil at all heights, the angle δ formed by the blade trailing edge 10r with respect to the virtual vertical plane V is the center line of the blade thickness. It is equal to the twist angle θ with respect to the virtual vertical plane V of 10c.

The torsional rudder 10 for a ship shown in the present embodiment has a cross-sectional shape with different dimensions for the airfoil at the upper position Hh and the airfoil at the lower position H1, and the upper position Hh from the cross-sectional shape of the airfoil at the lower position Hl. A shape that smoothly converges in the height direction up to the airfoil cross-sectional shape in FIG. In this embodiment, the cross-sectional shape of the airfoil from the lower position H1 to the intermediate position Hm is dimensionally the same, and the airfoil is gradually increased in the height direction from the intermediate position Hm to the upper position Hh. Yes. Here, the intermediate position Hm is set above the height of the propeller shaft 3x. The upper position Hh may be the upper end of the marine torsion rudder 10, and the lower position Hl may be the lower end of the marine torsion rudder 10.
In the present embodiment, the blade thickness center line 10 c coincides with the rotation axis 11, but the blade thickness center line 10 c does not necessarily coincide with the rotation axis 11.

FIG. 5 is an explanatory view showing the structure of a torsion rudder for a ship according to another embodiment.
Only the configuration different from that in FIG. 4 will be described, and the other components will be denoted by the same reference numerals and description thereof will be omitted.
The torsion rudder 10 for a ship according to the present embodiment has an asymmetric wing shape at the top and has a camber 10c.
The camber 10c is enlarged toward the upper side of the rudder.
The torsion rudder 10 shown in the present embodiment has an asymmetric wing shape from an intermediate position Hm to an upper position Hh, and gradually increases the wing shape in the height direction and the camber 10c. Further, the symmetric airfoil is formed from the lower position H1 to the intermediate position Hm.
In the present embodiment, the angle δ formed by the blade trailing edge 10r with respect to the virtual vertical plane V is the twist angle θ, which exceeds 0 ° and is 12 ° or less.
When the torsion rudder 10 is an asymmetric wing shape, the wing shape is changed by gradually twisting the wing shape around the rotating shaft 11 without changing the camber 10c, or by gradually changing the camber 10c. Twisting angle θ is formed by twisting. Further, while the camber 10c is gradually changed, the torsion angle θ can be formed by gradually twisting the airfoil around the rotating shaft 11.
It is also possible to form the torsion angle θ by gradually changing it in the height direction from the lower end.

FIG. 6 is an enlarged view of a main part of FIG. 2, and shows a torsion rudder 10 for a ship when the propeller 3 rotates inward in a biaxial stern catamaran type ship.
When the propeller 3 is rotating inward, the starboard side propeller 3 is counterclockwise and the port side propeller 3 is clockwise.
In this case, the starboard side ship twisted rudder 10 continuously changes the twist angle θ with respect to the virtual vertical plane V to the port side (inside the hull 1) of the virtual vertical plane V in the height direction of the rudder. Yes. In addition, the ship-side twisted rudder 10 on the port side continuously changes the twist angle θ with respect to the virtual vertical plane V toward the starboard side (inside the hull 1) of the virtual vertical plane V in the height direction of the rudder.
In particular, when the stern catamaran vessel has a skeg and the propeller 3 is attached to the rear of the skeg, the upward flow between the pair of propellers 3 is larger than the flow at the side of the hull 1. It is effective for the torsion rudder 10 to continuously change the twist angle θ with respect to the virtual vertical plane V in the hull 1 inside the virtual vertical plane V in the height direction of the rudder.
The addition of the twist angle θ is nothing but the addition of the rudder angle of attack so as to correspond to the asymmetrical flow at the stern.
By changing the torsion angle with respect to the virtual vertical plane V of the airfoil continuously in the height direction of the rudder on either the left or right side of the virtual vertical plane V, an appropriate angle of attack is provided for the asymmetrical flow, The lift is generated in the torsion rudder 10, which leads to the effect of reducing resistance, improving the thrust reduction coefficient, and improving the effective wake ratio.

In an asymmetric stern or biaxial stern catamaran vessel, the hull shape induces a flow in the left-right direction, i.e., in a stern catamaran vessel with skeg, for example, an asymmetric flow is induced on the left and right of the skeg. If this flows away to the rear of the hull 1, the energy used by the hull 1 to create this flow is lost as it is, and appears as an increase in resistance in the resistance state.
In the present embodiment, the torsion angle θ of the center line 10c of the rudder blade thickness with respect to the virtual vertical plane V is continuously changed in the height direction of the rudder on either one of the left and right sides of the virtual vertical plane V. This energy loss is recovered as lift by optimizing the cross-sectional distribution of the rudder. In a state where the propeller 3 is operated, a part of this asymmetric flow becomes a counter flow in the rotation direction of the propeller 3 and is collected by the propeller 3, but a flow passing over the propeller surface above the propeller 3 is not collected. Therefore, strong lift is generated by making the upper blade shape in the rudder height direction into a rudder shape with a large amount twisted from the virtual vertical plane V, and the flow that is not collected by the propeller 3 and the flow created by the propeller 3 The thrust generated by the entire rudder, including the lift of the rudder created by the rotating flow, is maximized, and the thrust reduction coefficient is improved compared to the normal rudder.

FIG. 7 shows the effect of the torsional rudder for a ship according to this embodiment with respect to a normal rudder by a water tank experiment.
When the twist angle θ and the rudder angle (the rudder) are adjusted (3 ° in the figure) to match the strength of the asymmetrical flow and the interference of the flow created by the propeller 3, the twisted rudder for the ship is compared with the normal rudder. The 2.9% thrust reduction coefficient is improved by installing, and it is improved by 2% or more compared to the case without the rudder angle of the normal rudder. To do. The effective wake rate at this time is also improved by 0.5% in the effective wake coefficient as the rudder elimination effect is improved as compared with the normal rudder. Furthermore, the effect for the rudder angle (the steering rudder) can be obtained by adjusting the twist angle θ, and the same effect can be obtained without the rudder angle (the rudder).

  As described above, according to the present embodiment, the asymmetric flow formed by the hull shape is used to generate lift, thereby improving the resistance reduction and the thrust reduction coefficient and improving the removal effect by the rudder. The flow rate can be improved.

  The present invention can be applied to a ship whose hull shape such as an asymmetric stern or a twin-skeg hull forms an asymmetric flow at the stern, thereby obtaining the maximum transportation efficiency.

DESCRIPTION OF SYMBOLS 1 Hull 2 Stern part 3 Propeller 3x Propeller shaft 10 Torsion rudder 10r Wing trailing edge 10c Center line (camber)
11 Rotating shaft Hh Upper position Hm Intermediate position H1 Lower position V Virtual vertical plane θ Torsion angle δ Angle formed by blade trailing edge

Claims (13)

A rudder attached to a stern part behind a propeller of a ship, wherein a rotation axis for rotating the rudder is positioned on a virtual vertical plane passing through the propeller axis, a cross-sectional shape of the rudder is a wing shape, The torsion angle of the airfoil with respect to the virtual vertical plane continuously changes in the height direction of the rudder on either the left or right side of the virtual vertical plane so as to correspond to the asymmetric flow, and the rudder blade A marine torsion rudder characterized in that a rear edge is gradually separated from the virtual vertical plane toward the upper end . Rudder twist for vessel according to claim 1, characterized in that the formation of the torsion angle by twisting the airfoil around the rotating shaft. The torsional rudder for a ship according to claim 1 or 2 , wherein the airfoil has a camber. The torsion rudder for a ship according to claim 3 , wherein the camber becomes larger toward the upper side of the rudder. Marine twisted rudder according to one of claims 1 to 4, wherein the angle between the trailing edge with respect to the virtual vertical surface is less than 12 ° beyond the 0 °. A rudder attached to a stern part behind a propeller of a ship, wherein a rotation axis for rotating the rudder is positioned on a virtual vertical plane passing through the propeller axis, a cross-sectional shape of the rudder is a wing shape, In order to correspond to the asymmetric flow, the twist angle of the airfoil with respect to the virtual vertical plane continuously changes in the height direction of the rudder on either the left or right of the virtual vertical plane, A torsion rudder for a ship, which has a camber, and becomes larger as the camber moves upwards of the rudder. The torsion rudder for a ship according to claim 6, wherein an angle formed by a trailing edge of the rudder with respect to the virtual vertical plane is greater than 0 ° and equal to or less than 12 °. The airfoil in the upper part of the rudder and the airfoil in the lower part of the rudder are different in cross-sectional shape, from the cross-sectional shape of the airfoil in the lower part to the cross-sectional shape of the airfoil in the upper part, marine twisted rudder according to one of claims 1 to 7, wherein, characterized in that a shape of smoothly converging the height direction. The marine torsion rudder according to claim 8 , wherein the cross-sectional shape of the airfoil at the lower portion of the rudder is a symmetric airfoil. Vessel equipped with a twist rudder characterized by being equipped with a marine twist rudder according to one of claims 1 to 9. The ship equipped with a torsional rudder according to claim 10 , wherein the ship is a stern catamaran type ship. The ship equipped with a torsion rudder according to claim 11 , wherein the stern catamaran ship has a skeg. The ship equipped with the torsion rudder according to claim 12 , wherein the propeller is attached to the rear of the skeg.