JP7145945B2 - Propulsion efficiency improvement device - Google Patents

Description

The present invention relates to a propulsion efficiency improvement device.

2. Description of the Related Art Recently, various technologies have been developed to reduce energy consumption during ship operation.

One example of an energy saving technique is a duct placed in front of the propeller.

The ducts create additional thrust while passing the flow moving aft along the surface of the hull. In this case, the duct can be a factor in increasing propulsion efficiency.

However, since the duct acts as resistance from another aspect, it also becomes a factor that reduces propulsion efficiency.

The technical problem of the present invention is to provide a device for improving propulsion efficiency.

According to one aspect of the propulsion efficiency improvement device of the present invention for solving the technical problem, a duct that is arranged in front of the propeller and has an arc shape to generate thrust; A propulsion efficiency improving device may be provided that includes a plurality of front-flow stationary blades that are supported by a boss portion and that generate a swirl flow in a direction opposite to the rotation direction of the propeller.

The duct may have a convex camber in a direction toward the stern boss portion, and the plurality of forward fixed vanes may have a convex camber in a rotational direction of the propeller.

The propulsion efficiency improving device mutually connects a first end portion of the duct in the propeller rotation direction and a first outer front flow fixed wing, which is positioned last in the propeller rotation direction, among the plurality of front flow fixed blades. a second end portion of the duct in a direction opposite to the rotational direction of the propeller; a second connection portion interconnecting the outer front flow fixed vanes, wherein the first connection portion connects the first end portion of the duct and the first outer front flow fixed blade having different camber shapes. The second connecting portion may have a shape for continuously connecting the second terminal end portion of the duct and the second outer front flow stationary blade having the same camber shape.

The duct has an arc shape extending from a lower left area to an upper right area with respect to the center line of the arc formed by the duct, and the plurality of front flow fixed vanes are arranged along the center line of the arc formed by the duct. may be spaced apart from each other from the left lower region to the right upper region.

The propeller rotates clockwise when viewed from the rear, and the number of front-flow fixed wings positioned on the port side of the hull out of the plurality of front-flow fixed wings may be greater than the number of front-flow fixed wings positioned on the starboard side. good.

A center line of an arc formed by the duct may be located above the rotation axis of the propeller.

The distance between the center line of the arc formed by the duct and the rotation axis of the propeller may be 0.1 to 0.4 times the radius of the propeller.

The duct may be located within the rotation zone of the propeller.

According to another aspect of the propulsion efficiency improving apparatus of the present invention, a plurality of forward fixed blades supported by a stern boss in front of a propeller and generating a swirling flow in a direction opposite to the rotation direction of the propeller; a duct that is supported at the terminal end of the forward fixed wing and has an arc shape to generate thrust; and a connecting portion that interconnects the duct and the forward fixed wing.

The duct may have a convex camber in a direction toward the stern boss portion, and the plurality of forward fixed vanes may have a convex camber in a rotational direction of the propeller.

The connecting portion interconnects a first end portion of the duct in the propeller rotation direction and a first outer front flow fixed blade that is positioned last in the propeller rotation direction among the plurality of front flow fixed blades. a first connecting portion, a second end portion of the duct in the direction opposite to the rotational direction of the propeller, and a second outer front end portion of the plurality of forward fixed blades located last in the direction opposite to the rotational direction of the propeller. a second connection interconnecting the flow fixed vanes, wherein the first connection continuously connects the first terminal end of the duct and the first outer front flow fixed vanes having different camber shapes. and the second connecting portion may have a shape that continuously connects the second terminal end portion of the duct and the second outer front flow fixed wing having the same camber shape.

The first connection part and the second connection part may be separately manufactured and coupled to the duct, the first outer front fixed wing and the second outer front fixed wing, respectively.

According to still another aspect of the propulsion efficiency improving apparatus of the present invention, there is provided a duct which is arranged in front of the propeller and has an arc shape to generate thrust; a plurality of forward fixed vanes for generating a swirling flow in a direction opposite to the direction of rotation of the propeller, wherein the duct extends from a first end in the direction of rotation of the propeller to a second end in the direction opposite to the direction of rotation of the propeller. It may have a shape in which the length of the cord changes as it goes to the part.

A first outer fore-flow fixed wing positioned last in the propeller rotation direction among the plurality of fore-flow fixed wing has a shape in which a cord length decreases from a root to a tip, and the duct has a shape of the The plurality of forward fixed blades have a shape in which the length of the cord increases and then decreases as it goes from a first terminal end in the direction of rotation of the propeller to a second terminal end in the direction opposite to the direction of rotation of the propeller. Among them, the second outer front flow stationary blade, which is positioned last in the direction opposite to the rotating direction of the propeller, may have a shape in which the cord length decreases from the root to the tip.

A first connection interposed between a first end portion of the duct in the propeller rotation direction and a first outer front flow fixed blade positioned last in the propeller rotation direction among the plurality of front flow fixed blades. a second end portion of the duct in the direction opposite to the rotational direction of the propeller; and a second outer front fixed blade located last in the direction opposite to the rotational direction of the propeller among the plurality of front fixed blades. and a second connecting portion interposed between and, wherein the first connecting portion has a cord length that decreases from the tip of the first outer forward fixed vane to the first terminal end of the duct. and the second connecting part has a shape in which the cord length decreases and then increases as it goes from the tip of the second outer front flow stationary wing to the second terminal end of the duct. can.

In a flattened view of an outward facing side of the duct, the curve formed by the leading edge of the duct may have a single curvature.

According to still another aspect of the propulsion efficiency improving apparatus of the present invention, there is provided a duct which is arranged in front of the propeller and has an arc shape to generate thrust; a plurality of forestream stators for generating a swirling flow in the opposite direction, the plurality of forestream stators located at other positions along the length of the hull.

Between the first outer front fixed wing positioned last in the direction of rotation of the propeller and the second outer front fixed wing positioned last in the direction opposite to the direction of rotation of the propeller among the plurality of front fixed blades may be positioned forward of the first outer fore-flow fixed wing and the second outer fore-flow fixed wing.

the inner front fixed wing has one or more pieces, and the tip of the inner front fixed wing fixed to the inner surface of the duct has a front end located behind the leading edge of the duct, A trailing end may lie forward of the trailing edge of the duct.

The inner front fixed wing, the first outer fixed front wing, and the second outer front fixed wing have the same cord length at the root and the tip, and the inner front fixed wing and the first outer front fixed wing have the same chord length at the root and at the tip. A longitudinal distance between the outer front flow fixed wing and the second outer front flow fixed wing may be 0.05 to 0.15 times the cord length of the root of the inner front flow fixed wing.

According to the embodiment of the present invention, the duct is supported using a general structure by using the front-flow fixed wing that generates a swirling flow in the direction opposite to the rotating direction of the propeller as a support that supports the duct. Unlike the conventional art, the propulsion efficiency can be improved by increasing the thrust of the propeller.

It is the perspective view which looked at the propulsion efficiency improvement apparatus by one Embodiment of this invention from the left rear. 2 is a perspective view with the propeller of FIG. 1 removed; FIG. It is the figure which looked at the propulsion efficiency improvement apparatus by one Embodiment of this invention from the back. It is the figure which looked at the propulsion efficiency improvement apparatus by one Embodiment of this invention from the left side. FIG. 4 is a perspective view of the propulsion efficiency improving device according to the embodiment of the present invention as seen from the rear left side, and is a view in which a cross-sectional shape is added to the duct and the front fixed wing. Fig. 2 is a partial view from the left side, with the duct omitted, according to an embodiment of the present invention; FIG. 4 is a diagram showing an exploded view of the outer surface of the combination of the duct, the first outer front fixed wing and the second outer front fixed wing according to one embodiment of the present invention; FIG. 7 is a perspective view of a propulsion efficiency improving device according to a second embodiment of the present invention, viewed from the rear left side; FIG. 9 is a perspective view with the propeller of FIG. 8 removed; It is the figure which looked at the propulsion efficiency improvement apparatus by 2nd Embodiment of this invention from the back. It is the figure which looked at the propulsion efficiency improvement apparatus by 2nd Embodiment of this invention from the left side. It is the perspective view which looked at the propulsion efficiency improvement apparatus by 2nd Embodiment of this invention from the left rear, and is the figure which added the cross-sectional shape to the duct and the front fixed wing. FIG. 11 is a view showing an exploded view of the outer surface of the combination of the duct, the first outer fixed wing, and the second outer fixed wing according to the second embodiment of the present invention; It is the figure which looked at the propulsion efficiency improvement apparatus by 3rd Embodiment of this invention from the left side. FIG. 15 is a diagram in which the duct of FIG. 14 is omitted; FIG. 11 is a perspective view of a propulsion efficiency improving device according to a third embodiment of the present invention, viewed from the rear left side; FIG. 11 is a perspective view of a propulsion efficiency improving device according to a fourth embodiment of the present invention, viewed from the rear left side; 18 is a perspective view with the propeller of FIG. 17 removed; FIG. FIG. 5 is a diagram for explaining the effect of the propulsion efficiency improvement device according to some embodiments of the present invention; FIG. 5 is a diagram for explaining the effect of the propulsion efficiency improvement device according to some embodiments of the present invention; FIG. 5 is a diagram for explaining the effect of the propulsion efficiency improvement device according to some embodiments of the present invention; FIG. 5 is a diagram for explaining the effect of the propulsion efficiency improvement device according to some embodiments of the present invention; FIG. 5 is a diagram for explaining the effect of the propulsion efficiency improvement device according to some embodiments of the present invention; FIG. 5 is a diagram for explaining the effect of the propulsion efficiency improvement device according to some embodiments of the present invention;

Since the present invention is capable of various modifications and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the invention to any particular embodiment, but should be understood to include all transformations, equivalents or alternatives falling within the spirit and scope of the invention. . In describing the present invention, detailed descriptions of related known technologies will be omitted if it is determined that they may obscure the gist of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing with reference to the accompanying drawings, the same or corresponding components are given the same drawing numbers, and duplicate descriptions thereof will be omitted.

FIG. 1 is a perspective view of a propulsion efficiency improving device according to an embodiment of the present invention as seen from the left rear, FIG. 2 is a perspective view with the propeller of FIG. 1 removed, and FIG. 3 is an embodiment of the present invention. 4 is a view of the propulsion efficiency improvement device according to the embodiment of the present invention as seen from the rear, and FIG. 4 is a left side view of the propulsion efficiency improvement device according to the embodiment of the present invention. For reference, in FIGS. 1 to 4, the positive side in the X direction means the front, and the positive side in the Y direction means the left direction.

Referring to FIGS. 1 to 4, a propulsion efficiency improving device 100 according to one embodiment of the present invention includes a duct 110 and forward flow fixed wings (131, 132, 133, 134).

Duct 110 is arranged in front of propeller 30 . The propeller 30 is arranged behind the stern boss portion 20 . The propeller 30 rotates to generate thrust. In this embodiment, the propeller 30 rotates clockwise when referring to FIGS. 1-3. That is, the propeller 30 rotates clockwise when viewed from behind.

Duct 110 has an arc shape.

As an example, the duct 110 may have an arc shape extending from the lower left region to the upper right region with respect to the center line AD of the arc formed by the duct 110 as shown in FIGS.

As another example, although not shown in the drawings, the duct may have an arcuate shape extending from the left upper region to the right upper region with respect to the center line of the arc formed by the duct.

The arc angle formed by the duct 110 is preferably less than 180 degrees.

The duct 110 has a structure that partially surrounds the stern boss portion 20 .

The centerline AD of the arc formed by the duct 110 can be located above the rotation axis AP of the propeller 30 as shown in FIG.

At this time, the distance H between the center line AD of the arc formed by the duct 110 and the rotation axis AP of the propeller 30 may be greater than or equal to the radius of the propeller 30 and less than or equal to 0.4 times. If the distance H between the center line AD of the arc formed by the duct 110 and the rotation axis AP of the propeller 30 exceeds 0.4 times the propeller 30, the range in which the forward fixed blades can be installed is significantly restricted.

Furthermore, the distance H between the center line AD of the arc formed by the duct 110 and the rotation axis AP of the propeller 30 may be 0.1 times or more and 0.4 times or less the radius of the propeller 30 .

Duct 110 is located within the rotation area of propeller 30 . At this time, the flow passing through the duct 110 can flow into the propeller 30 in an aligned form, and the propulsion efficiency of the propeller 30 can be improved.

At this time, the radius of the duct 110 is smaller than or equal to the radius of the propeller minus the distance between the center line AD of the arc of the duct 110 and the rotation axis AP of the propeller 30 .

Duct 110 generates thrust. For example, the duct 110 has an airfoil cross-section and has a convex camber in the direction toward the aft boss 20 . This will be described later.

As the flow moving backward along the hull 10 passes through the duct 110 , lift is generated in the cross section of the duct 110 . A component of the lift that is aligned with the longitudinal direction of the hull 10 (for example, the X-axis direction) acts as a thrust for propelling the hull 10 .

Duct 110 may be supported at the stern of hull 10 by separate support members (not shown).

The forward fixed wings (131, 132, 133, 134) support the duct 110 against the stern boss 20.

The forward flow fixed vanes (131, 132, 133, 134) are provided in multiples.

As an example, the number of upstream fixed vanes (131, 132, 133, 134) may be four as shown in FIGS.

As another example, the number of front flow fixed vanes may be three, five, etc., although not shown in the drawings.

A plurality of upstream fixed vanes (131, 132, 133, 134) are spaced apart in the rotational direction of propeller 30 as shown in FIGS. In other words, the plurality of upstream fixed vanes (131, 132, 133, 134) may be spaced apart in an arcuate direction about the centerline AD of the arc formed by the duct 110 as in FIGS.

As an example, the plurality of front flow fixed vanes (131, 132, 133, 134) are arranged from the lower left area to the upper right area with respect to the center line AD of the arc formed by the duct 110 as shown in FIGS. They can be spaced apart from each other.

As another example, although not shown in the drawings, a plurality of front-flow fixed vanes may be spaced apart from each other from the left upper region to the right upper region with respect to the center line of the arc formed by the duct.

A plurality of upstream fixed vanes (131, 132, 133, 134) generate a swirling flow in a direction opposite to the rotating direction of propeller 30. FIG.

The swirling flow generated by the front fixed blades (131, 132, 133, 134) flows into the propeller 30 and reduces the swirling flow in the rotation direction of the propeller 30, thereby improving the propulsion efficiency. In other words, when the swirling flow in the direction opposite to the rotating direction of the propeller 30 is generated by the forward fixed blades (131, 132, 133, 134), the angle of attack of the flow flowing into the propeller 30 increases, and the propeller 30 generates Thrust is increased, which improves propulsion efficiency.

FIG. 5 is a perspective view of the propulsion efficiency improving device according to the embodiment of the present invention as seen from the rear left side, and is a view in which the cross-sectional shape is added to the duct and the fixed front wing.

Referring to FIG. 5, in this embodiment the propeller (not shown) rotates clockwise when viewed from the rear. At this time, the plurality of upstream fixed blades (131, 132, 133, 134) are arranged to generate a swirling flow in a direction opposite to the rotating direction of the propeller (not shown) as shown in FIG. (not shown) has a convex camber in the direction of rotation.

The propulsion efficiency improving device 100 according to one embodiment of the present invention described above serves as a support for supporting the duct 110 that generates thrust with respect to the stern boss portion 20. Flow fixed vanes (131, 132, 133, 134) are used.

In this connection, in order to support the thrust-producing duct, which is usually arranged in front of the propeller, unlike the forward flow fixed wing (131, 132, 133, 134) according to this embodiment, a simple shape A support member is used. Such simple shaped support members acted as resistance and became a factor in increasing the resistance of the ship.

However, the propulsion efficiency improving device 100 according to one embodiment of the present invention includes forward fixed wings (131, 132, 133, 134) that generate a swirling flow in the direction opposite to the rotating direction of the propeller 30 as a support that supports the duct 110. ), the thrust of the propeller 30 is increased to improve the propulsion efficiency, unlike the conventional art.

In this embodiment, the number of the front fixed wing (132, 133, 134) positioned on the port side of the hull 10 among the plurality of front fixed wing (131, 132, 133, 134) is More than 131 numbers.

More specifically, when examining the distribution of the wake flowing into the propeller in a barehull state without a fixed front wing, it is found that a wake is generated on the port side in the same direction as the propeller rotation direction, and a wake is generated on the starboard side by the propeller. A wake is generated in the direction opposite to the direction of rotation of the

On the port side where the wake in the same direction as the rotation direction of the propeller 30 is generated, the front flow fixed wing (132, 133, 134) is attached to the front flow fixed wing (132, 133, 134) at a small pitch angle (mounting angle). The incoming inflow can be changed to the direction opposite to the rotation direction of the propeller 30, but on the starboard side where the wake is generated in the direction opposite to the rotation direction of the propeller 30, the forward fixed wing 131 has a larger pitch angle ( The inflow flowing into the front stationary blade 131 can be changed to the direction opposite to the rotating direction of the propeller 30 only when the propeller 30 is installed at the mounting angle).

In this case, on the port side, where a swirling flow in the direction opposite to the rotation direction of the propeller 30 can be generated at a small pitch angle, the increase in resistance due to the installation of the forward fixed blades (132, 133, 134) is small, but the propeller can be rotated only at a large pitch angle. On the starboard side where a swirling flow can be generated in the direction opposite to the direction of rotation of 30, the increase in resistance due to the attachment of the forward fixed wing 131 becomes excessive. Therefore, it is preferable to arrange more forward fixed wings on the port side than on the starboard side for high propulsive efficiency.

In this embodiment, the first terminal end of the duct 110 in the direction of rotation of the propeller 30 and the first outer side of the plurality of forward fixed blades (131, 132, 133, 134) positioned last in the direction of rotation of the propeller 30 The upstream fixed vanes 131 are interconnected. The first outer upstream fixed vane 131 can be located in the upper right region with respect to the center line AD of the arc formed by the duct 110 as shown in FIG.

A second end portion of the duct 110 in the opposite direction to the rotation direction of the propeller 30 and a second end portion of the plurality of forward fixed vanes (131, 132, 133, 134) located last in the opposite direction to the rotation direction of the propeller 30. The outer upstream stator vanes 132 are interconnected. The second outer upstream fixed wing 132 may be located in the lower left region with respect to the center line AD of the arc formed by the duct 110 as shown in FIG.

In this embodiment, the duct 110 and the first outer front flow stationary wing 131 differ in camber shape.

More specifically, the duct 110 has a convex camber toward the stern boss portion 20 as shown in FIG. .

In other words, the duct 110 has a convex camber toward the inside of the space surrounded by the duct 110, the first outer front fixed wing 131, and the second outer front fixed wing 132. The blade 131 has a convex camber toward the outside of the space surrounded by the duct 110 , the first outer fixed front wing 131 and the second outer front fixed wing 132 .

In the present embodiment, the first end portion of the duct 110 and the first outer front flow stationary wing 131 having different camber shapes as described above are continuously connected.

For example, as shown in FIG. 5, the first end portion of the duct 110 and the first outer front fixed wing 131 having convex cambers in opposite directions have a shape in which the cambers gradually disappear toward the boundary between them.

In this embodiment, the duct 110 and the second outer upstream fixed wing 132 are identical in camber shape.

More specifically, the duct 110 has a convex camber toward the stern boss portion 20 as shown in FIG. .

In other words, the duct 110 and the second outer front fixed wing 132 are both convex toward the inside of the space surrounded by the duct 110, the first outer front fixed wing 131 and the second outer front fixed wing 132. of camber.

In this embodiment, the second end portion of the duct 110 and the second outer front flow stationary blade 132 having the same camber shape as described above are continuously connected.

FIG. 6 is a partial view from the left side according to an embodiment of the present invention, showing a state in which the duct is omitted.

Referring to Figures 5 and 6, the first outer leading stator 131, the second outer leading stator 132 and the inner leading stator (133, 134) may have a swept wing shape. At this time, the first outer front-flow fixed wing 131, the second outer front-flow fixed wing 132, and the inner front-flow fixed wing (133, 134) have a shape in which the leading edge hangs rearward from the root toward the tip.

In this embodiment, the plurality of upstream fixed vanes (131, 132, 133, 134) may each have a trailing edge on the same plane perpendicular to the center line AD of the arc formed by the duct 110. At this time, the plurality of front flow fixed blades (131, 132, 133, 134) are closest to the propeller (not shown), so that the propeller generated by the front flow fixed blades (131, 132, 133, 134) The swirling flow in the direction opposite to the direction of rotation of the propeller 30 can immediately flow into the propeller 30, improving the propulsion efficiency.

In this embodiment, the first outer forerunning stator 131, the second outer forerunning stator 132 and the inner forerunning stator (133, 134) may all have the same cord length at the root. And, the first outer front flow fixed wing 131, the second outer front flow fixed wing 132 and the inner front flow fixed wing (133, 134) may all have the same cord length at the tip. Even if the cord length at the root is longer than the cord length at the tip, each of the first outer front flow fixed wing 131, the second outer front flow fixed wing 132, and the inner front flow fixed wing (133, 134) good.

Referring to FIG. 5, in this embodiment, the tips of the inner forward stator vanes (133, 134) may be fixed to the inner surface of the duct 110. FIG.

At this time, the front end of the tip of the inner front fixed wing (133, 134) is positioned behind the leading edge of the duct 110, and the rear end of the tip of the inner front fixed wing (133, 134) is positioned at the trailing edge of the duct 110. located forward of the edge.

In this case, the round bar forming the leading edge of the inner front fixed wing (133, 134) does not interfere with the round bar forming the leading edge of the duct 110, and the inner front fixed wing (133, 134) is trailing. Since the round bar forming the edge does not interfere with the round bar forming the trailing edge of the duct 110, workability can be improved. For reference, bonding the end of one rod to the side surface of another rod is much less workable than bonding the end of one rod to one side of a flat plate.

FIG. 7 is an exploded view of the outer surface of the combination of the duct, the first outer fixed wing, and the second outer fixed wing according to one embodiment of the present invention.

Referring to FIG. 7, the trailing edge 110b of the duct 110 may have a linear shape and the leading edge 110a of the duct 110 may have a forwardly convex curve in the developed view.

In this case, the most convex peak portion in the developed view of the duct 110 approaches the hull 10, making it easier to fix the duct 110 to the hull 10. FIG.

More specifically, the duct 110 having a developed view as shown in FIG. 7 has a structure in which the peak portion protrudes forward as shown in FIG. At this time, the duct 110 can be supported with respect to the hull 10 even with a support member (not shown) having a short length because the peak portion approaches the hull 10 . A support member having a short length is structurally more rigid than a support member having a long length, so that the duct 110 can be stably supported on the hull 10 .

Referring to FIG. 7, the curve formed by the leading edge 110a of the duct 110 in the developed view may have a single curvature R. As shown in FIG. In this case, the duct 110 has a shape in which the cord length increases and then decreases from the first end portion 110c to the second end portion 110d.

Generally, a duct has a structure in which a plate forming a pressure surface and a suction surface is coupled to a round bar forming a leading edge.

In order to manufacture the duct 110 so that the curve formed by the leading edge 110a of the duct 110 in the developed view has a single curvature R, the round bar is bent to have one curvature. In this case, workability is greatly improved compared to the case where the round bar is bent so as to have two or more curvatures.

Referring to FIG. 7, the first outer front flow stationary wing 131 has a shape in which the cord length decreases from the root 131c to the tip 131d. The second outer upstream fixed wing 132 has a shape in which the cord length decreases from the root 132c to the tip 132d.

FIG. 8 is a perspective view of a propulsion efficiency improving device according to another embodiment (second embodiment) of the present invention as seen from the rear left side, FIG. 9 is a perspective view of FIG. 8 with the propeller removed, and FIG. is a rear view of a propulsion efficiency improvement device according to another embodiment (second embodiment) of the present invention, and FIG. 11 shows a propulsion efficiency improvement device according to another embodiment (second embodiment) of the present invention. FIG. 12 is a left side view of a propulsion efficiency improving device according to another embodiment (second embodiment) of the present invention, and FIG. It is an additional figure. For reference, in FIGS. 8 to 12, the positive side in the X direction means the front, and the positive side in the Y direction means the left direction.

8 to 12, a propulsion efficiency improving device 100' according to another embodiment (second embodiment) of the present invention includes a duct 110, front flow fixed wings (131, 132, 133, 134), first A connecting portion 150 and a second connecting portion 160 may be included. A propulsion efficiency improving device 100' according to another embodiment of the present invention differs from the propulsion efficiency improving device 100 according to the above-described embodiment in that it further includes a first connection part 150 and a second connection part 160. .

The first connection part 150 is the first terminal end of the duct 110 in the rotation direction of the propeller 30 and the last one of the plurality of front fixed vanes (131, 132, 133, 134) in the rotation direction of the propeller 30. 1 outer upstream fixed vanes 131 are interconnected.

The first connection part 150 is manufactured separately from the duct 110 and the first outer front fixed wing 131 , and both ends of the first connection part 150 are connected to the first end of the first outer front fixed wing 131 and the duct 110 . can be respectively coupled to the parts.

The second connection part 160 is a second end part of the duct 110 in the direction opposite to the rotation direction of the propeller 30 and one of the plurality of front fixed vanes (131, 132, 133, 134) in the direction opposite to the rotation direction of the propeller 30. , the second outer upstream stator vane 132 located last in the .

The second connecting part 160 is manufactured separately from the duct 110 and the second outer front fixed wing 132 , and both ends of the second connecting part 160 are connected to the second end of the second outer front fixed wing 132 and the duct 110 . can be respectively coupled to the parts.

In this embodiment, the duct 110 and the first outer front flow stationary wing 131 differ in camber shape.

More specifically, the duct 110 has a convex camber toward the stern boss portion 20 as shown in FIG. have.

In other words, the duct 110 has a convex camber toward the inside of the space surrounded by the duct 110, the first outer front flow fixed wing 131, and the second outer front flow fixed wing 132. The fixed wing 131 has a convex camber toward the outside of the space surrounded by the duct 110 , the first outer front-flow fixed wing 131 and the second outer front-flow fixed wing 132 .

The first connection part 150 according to the present embodiment has a shape that continuously connects the first end part of the duct 110 and the first outer front flow stationary wing 131 having different camber shapes as described above.

For example, as shown in FIG. 5, the first connecting portion 150 includes a first region 151 having a camber that is convex in the same direction as the camber of the duct 110 and a camber that is convex in the same direction as the camber of the first outer front flow fixed wing 131. It includes a second region 152 having a curved camber. The cambers of the first region 151 and the second region 152 gradually disappear while approaching the boundary between the first region 151 and the second region 152, respectively.

In this embodiment, the duct 110 and the second outer upstream fixed wing 132 are identical in camber shape.

More specifically, the duct 110 has a convex camber toward the stern boss portion 20 as shown in FIG. have.

In other words, the duct 110 and the second outer front fixed wing 132 are both convex toward the inside of the space surrounded by the duct 110, the first outer front fixed wing 131 and the second outer front fixed wing 132. of camber.

The second connecting portion 160 according to the present embodiment has a shape that continuously connects the second end portion of the duct 110 and the second outer front flow fixed wing 132 having the same camber shape as described above.

For example, as shown in FIG. 5, the second connecting portion 160 has a convex camber toward the inside of the space surrounded by the duct 110, the first outer fixed wing 131, and the second outer fixed wing 160. have.

FIG. 13 is an exploded view of a combination of a duct, a first outer fixed wing, and a second outer fixed wing with respect to the outer surface according to another embodiment (second embodiment) of the present invention.

Referring to FIG. 13, the trailing edge 110b of the duct 110 may have a linear shape and the leading edge 110a of the duct 110 may have a forwardly convex curve in the developed view.

In this case, the most convex peak portion in the developed view of the duct 110 approaches the hull 10 , making it easier to fix the duct 110 to the hull 10 .

Referring to FIG. 13, the curve formed by the leading edge 110a of the duct 110 in the developed view may have a single curvature. In this case, the duct 110 has a shape in which the cord length increases and then decreases from the first end portion 110c to the second end portion 110d.

Referring to FIG. 13, the first outer front flow fixed wing 131 has a shape in which the cord length decreases from the root 131c to the tip 131d. The second outer upstream fixed wing 132 has a shape in which the cord length decreases from the root 132c to the tip 132d.

Also, the first connection part 150 has a shape in which the cord length decreases and then increases from the tip 131d of the first outer front fixed wing 131 to the first end part 110c of the duct 110 . In particular, a portion 153 of the first connecting portion 150 having the shortest cord length is the portion where the cord length decreases and then increases at the first connecting portion 150 . A portion 153 having the shortest code in the first connecting portion 150 corresponds to the boundary between the first area (151 in FIG. 10) and the second area (152 in FIG. 10). The second connection part 160 may have a shape in which the cord length decreases and then increases from the tip 132 d of the second outer front stationary wing 132 toward the second terminal end 110 d of the duct 110 .

Reference numerals 131a, 150a, 110a, 160a and 132a indicate leading edges, and reference numerals 131b, 150b, 110b, 160b and 132b indicate trailing edges.

FIG. 14 is a left side view of a propulsion efficiency improving device according to another embodiment (third embodiment) of the present invention, and FIG. 15 is a view in which the duct in FIG. 14 is omitted. FIG. 16 is a perspective view of a propulsion efficiency improving device according to another embodiment (third embodiment) of the present invention, viewed from the rear left side.

14 to 16, a propulsion efficiency improving device 100'' according to another embodiment (third embodiment) of the present invention includes a duct 110 and a plurality of front flow fixed wings (131, 132, 133, 134). , a first connecting portion 150 , and a second connecting portion 160 .

A propulsion efficiency improving device 100 ″ according to another embodiment (third embodiment) of the present invention is configured such that the front-to-rear direction positions of the plurality of front flow fixed vanes ( 131 , 132 , 133 , 134 ) are the above-described one embodiment of the present invention. It is different from the propulsion efficiency improvement device 100' according to the form.

In this embodiment, the inner front flow fixed vanes (133, 134) are located forward of the first outer front flow fixed blade 131 and the second outer front flow fixed blade 132. As shown in FIG.

Even in this case, the front end of the tip of the inner front fixed wing (133, 134) is located behind the leading edge of the duct 110, and the rear end of the tip of the inner front fixed wing (133, 134) is positioned behind the leading edge of the duct 110. located forward of the trailing edge.

The longitudinal distance L between the inner front fixed wing (133, 134), the first outer front fixed wing 131 and the second outer front fixed wing 132 in this embodiment is the inner front fixed wing (133, 134) It may be 0.05 times or more and 0.15 times or less of the cord length of the root of the first outer front fixed wing 131 or the second outer front fixed wing 132 . For reference, the cord lengths of the routes of the inner front flow fixed vanes (133, 134), the first outer front flow fixed blades 131 and the second outer front flow fixed blades 132 in this embodiment are all the same.

In this way, when the inner front fixed wing (133, 134) is positioned ahead of the first outer front fixed wing 131 and the second outer front fixed wing 132, the front fixed wing (131, 132, 133, 134) are located at the same position in the longitudinal direction of the hull 10, the resistance acting on the hull 10 is reduced.

This is achieved by locating the inner forerunning fixed vanes (133, 134) at a predetermined distance L ahead of the first outer forerunning vane 131 and the second outer forerunning vane 132, thereby This is because the Venturi effect generated between the fixed wing (133, 134) and the first outer front flow fixed wing 131 and the second outer front flow fixed wing 132 is weakened, and the resistance applied to the hull 10 is reduced.

If the front-rear distance between the inner front fixed wing (133, 134) and the first outer front fixed wing 131 and the second outer front fixed wing 132 exceeds the above range, the inner front fixed wing (133, 134) and the propeller (not shown), the flow induced by the inner front flow fixed blades (133, 134) does not flow sufficiently into the propeller (not shown), and the propulsion efficiency decreases. can decline.

When the front-rear distance between the inner front fixed wing (133, 134) and the first outer front fixed wing 131 and the second outer front fixed wing 132 is smaller than the above range, the inner front fixed wing (133, 134) ) and the first outboard 131 and the second outboard 132 , the Venturi effect can increase the resistance on the hull 10 .

FIG. 17 is a perspective view of a propulsion efficiency improving device according to another embodiment (fourth embodiment) of the present invention as seen from the rear left side, and FIG. 18 is a perspective view of FIG. 17 with the propeller removed.

Referring to FIGS. 17 and 18, a propulsion efficiency improving device 100a according to another embodiment (fourth embodiment) of the present invention includes a duct 110 and a plurality of front flow stationary wings (131, 132, 133, 134). .

An exploded view of duct 110 may have a trailing edge 110b of duct 110 having a straight shape and a leading edge 110a of duct 110 having a forwardly convex curve, as described with reference to FIG. The duct 110 has a structure in which the peak portion protrudes forward as shown in FIG. At this time, the duct 110 can be supported with respect to the hull 10 even with a support member (not shown) having a short length by bringing the peak portion closer to the hull 10 . A support member having a short length is structurally more rigid than a support member having a long length, so that the duct 110 can be stably supported on the hull 10 . Meanwhile, unlike the contents described with reference to FIGS. 8 to 16, separate connection parts 150 and 160 may not be included.

The inner front flow fixed vanes (133, 134) are located ahead of the first outer front flow fixed blades 131 and the second outer front flow fixed blades 132 as described in FIGS. 14 to 16 .

The front end of the tip of the inner foreflow fixed wing (133, 134) is located behind the leading edge of the duct 110, and the rear end of the tip of the inner foreflow fixed wing (133, 134) is ahead of the trailing edge of the duct 110. Located in

In this way, when the inner front fixed wing (133, 134) is positioned ahead of the first outer front fixed wing 131 and the second outer front fixed wing 132, the front fixed wing (131, 132, 133, 134) are located at the same position in the longitudinal direction of the hull 10, the resistance acting on the hull 10 is reduced.

Hereinafter, the fuel saving effect of the propulsion efficiency improving devices (100, 100', 100'', 100a) according to some embodiments of the present invention will be described in more detail with reference to FIGS. 19 to 22. FIG.

First, FIG. 19 shows a case where only a plurality of forward fixed blades (see 131, 132, 133 and 134 in FIGS. 1 to 18) are installed in front of the propeller. FIG. 20 shows a case where a plurality of forward fixed vanes and a circular duct (that is, full duct) are installed in front of the propeller. The circular duct has a shape formed so as to surround the front fixed wing in a circular shape. FIG. 21 shows a case where a plurality of upstream fixed vanes and a partial duct (that is, a partial duct) are installed in front of the propeller like the propulsion efficiency improving device according to some embodiments of the present invention.

When only the front fixed wing is installed (see Figure 19), when the front fixed wing and a circular duct are installed (see Figure 20), when the front fixed wing and some ducts are installed (see Figure 21) ) was tested for fuel savings in comparison to a propeller-only installation (ie, a comparative case), and the results are shown graphically in FIG. In FIG. 22, "stator" means a front fixed wing, "full duct" means a circular duct, and "partial duct" means a partial duct.

Referring to FIG. 22, the case where only the front fixed wing was installed (see FIG. 19) had a fuel saving effect of 2.0% compared to the comparative case. The installation of the forward fixed wing and circular duct (see FIG. 20) resulted in a 1.0% fuel saving effect compared to the comparative case. The installation of the forward fixed wing and some ducts (see Figure 21) resulted in a 3.0% fuel saving effect compared to the comparative case.

Additional tests were carried out to confirm why the fuel saving effect in the case of installing the front stream fixed wing and circular duct (see Figure 20) is relatively low compared to other cases, and the results are shown in Figure 23 and Figure 24.

Comparing Figures 23 and 24, it can be seen that in Figure 23 there is a hull pressure drop between the bottom of the aft boss and the circular duct (see D1). In contrast, in FIG. 24, it can be seen that no hull pressure drop occurs under the stern boss (see D2). When a hull pressure drop occurs, this creates a negative pressure in the lower part of the hull, increasing the hull resistance. Therefore, the fuel saving effect is lowered.

On the other hand, when compared with the case where only the front fixed wing is installed (see Fig. 19), the reason why the fuel saving effect when the front flow fixed wing and some ducts are installed (see Fig. 21) is better is as follows. It is as follows.

In the partial duct case (see FIG. 21), all front flow stators are connected to partial ducts and multiple support structures (ie, multiple support). Therefore, the use of some ducts (see FIG. 21) has higher structural stability than the case of installing only the cantilever-shaped forward fixed wing (see FIG. 19).

In addition, a front-flow stationary blade that generates a swirling flow may cause a cavity phenomenon due to a terminal vortex. Therefore, in the case of a front flow fixed vane only installation (see FIG. 19), additional features such as winglets must be installed to reduce the termination cavitation. However, when some ducts are used (see FIG. 21), all the front stationary blades are surrounded by some ducts, so the terminal vortex is basically blocked. Additional devices such as winglets are therefore unnecessary.

Although the embodiments of the present invention have been described above, those skilled in the art can add components, The present invention can be variously modified and changed by alteration, deletion or addition, etc., which also fall within the scope of the present invention.

10: Hull,
20: stern boss,
30: Propeller,
100: propulsion efficiency improvement device,
110: duct,
131: first outer forward fixed wing,
132: second outer forward fixed wing,
133, 134: inner forward fixed wing,
150: first connecting part,
160: Second connecting part.

Claims (19)

A duct that is arranged in front of the propeller, has an arc shape, and generates thrust;
a plurality of forward fixed blades that support the duct on the stern boss portion and generate a swirling flow in a direction opposite to the rotation direction of the propeller;
The duct and the first outer front fixed wing positioned at the end of the plurality of front fixed wing in the direction of rotation of the propeller have different camber shapes,
The propulsion efficiency improving device, wherein the first end portion of the duct and the first outer front fixed wing having convex cambers in opposite directions have a shape in which the cambers gradually disappear toward a boundary therebetween. The duct has a convex camber in a direction toward the stern boss,
2. The propulsion efficiency improving device according to claim 1, wherein said plurality of upstream fixed blades have a convex camber in the rotational direction of said propeller. the first end portion of the duct in the direction of rotation of the propeller and the first outer forward fixed wing are interconnected via a first connecting portion;
A second end portion of the duct in the direction opposite to the propeller rotation direction and a second outer front flow fixed blade located last in the opposite direction to the propeller rotation direction among the plurality of front flow fixed blades are the second end portions of the duct. interconnected via two connections,
the first connecting portion has a shape that continuously connects the first terminal end portion of the duct and the first outer front fixed wing, which have different camber shapes;
the second connecting portion has a shape that continuously connects the second terminal end portion of the duct and the second outer front fixed wing that have the same camber shape ;
The first connecting portion includes a first region having a convex camber in the same direction as the camber of the duct and connected to the first terminal end portion of the duct, and the camber of the first outer forward fixed wing. a second region having a convex camber in the same direction and connected to the first outer front flow fixed wing, wherein the cambers of the first region and the second region are respectively the first region and the second region; 3. The propulsion efficiency improving device according to claim 2, having a shape that gradually disappears toward the boundary with the region . the duct has an arc shape extending from a lower area on one side to an upper area on the other side with respect to the center line of the arc formed by the duct;
2. The propulsion of claim 1, wherein said plurality of upstream stator vanes are spaced apart from one another over a lower region on one side and an upper region on the other side with respect to a centerline of an arc formed by said duct. Efficiency improvement device. said propeller rotates clockwise when viewed from the rear;
2. The propulsion efficiency improving device according to claim 1, wherein the number of front-flow fixed wings located on the port side of the hull is greater than the number of front-flow fixed wings located on the starboard side of the plurality of front-flow fixed wings. 2. The propulsion efficiency improving device according to claim 1, wherein the center line of the arc formed by said duct is located above the rotation axis of said propeller. 2. The propulsion efficiency improving device according to claim 1, wherein the distance between the center line of the arc formed by the duct and the rotation axis of the propeller is 0.1 to 0.4 times the radius of the propeller. . 2. The propulsion efficiency improvement device of claim 1, wherein said duct is located within a rotation zone of said propeller. a plurality of front flow fixed blades supported by a stern boss in front of the propeller and generating a swirling flow in a direction opposite to the rotation direction of the propeller;
a duct that is supported by terminal end portions of the plurality of upstream fixed vanes, has an arc shape, and generates thrust;
a connecting portion interconnecting the duct and the upstream fixed wing;
The duct and the first outer front fixed wing positioned at the end of the plurality of front fixed wing in the direction of rotation of the propeller have different camber shapes,
A propulsion efficiency improving device, wherein the first end portion of the duct and the first outer front fixed wing having convex cambers in opposite directions have a shape in which the cambers gradually disappear toward a boundary therebetween. The duct has a convex camber in a direction toward the stern boss,
10. The propulsion efficiency improving device according to claim 9, wherein said plurality of upstream stationary blades have a convex camber in the rotational direction of said propeller. The connecting part is
a first connecting portion interconnecting the first terminal end portion of the duct in the direction of rotation of the propeller and the first outer forward fixed wing ;
A second end portion of the duct in the opposite direction of rotation of the propeller and a second outer front fixed blade that is positioned last in the direction opposite to the rotation direction of the propeller among the plurality of front fixed blades are interconnected. and a second connector that
the first connecting portion has a shape that continuously connects the first terminal end portion of the duct and the first outer front fixed wing, which have different camber shapes;
the second connecting portion has a shape that continuously connects the second terminal end portion of the duct and the second outer front fixed wing that have the same camber shape ;
The first connecting portion includes a first region having a convex camber in the same direction as the camber of the duct and connected to the first terminal end portion of the duct, and the camber of the first outer forward fixed wing. a second region having a convex camber in the same direction and connected to the first outer front flow fixed wing, wherein the cambers of the first region and the second region are respectively the first region and the second region; 11. The propulsion efficiency improving device according to claim 10, having a shape that gradually disappears toward the boundary with the region . 12. The method according to claim 11, wherein the first connecting part and the second connecting part are manufactured separately from the duct, the first outer fixed front wing and the second outer fixed front wing, and are connected to each other. Propulsion efficiency improvement device. 2. The duct according to claim 1, wherein the duct has a shape such that the cord length changes from the first end in the direction of rotation of the propeller toward the second end in the direction opposite to the direction of rotation of the propeller. Propulsion efficiency improvement device. The first outer front flow fixed wing has a shape in which the cord length decreases from the root toward the tip,
the duct has a shape in which the cord length increases and then decreases from the first end portion toward the second end portion ;
14. A second outer front fixed wing positioned last in a direction opposite to a rotational direction of said propeller among said plurality of front fixed wing has a shape in which a cord length decreases from a root to a tip. The propulsion efficiency improvement device described in . a first connecting portion interposed between the first terminal end portion of the duct in the propeller rotation direction and the first outer forward fixed wing ;
between the second end portion of the duct in the direction opposite to the propeller rotation direction and the second outer front flow fixed blade located last in the opposite direction to the propeller rotation direction among the plurality of front flow fixed blades; and a second connecting portion interposed therebetween ,
The first connecting part is
having a shape in which the cord length decreases and then increases as it goes from the tip of the first outer forward flow fixed vane to the first end portion of the duct ;
The second connecting part is
14. The propulsion efficiency improving device according to claim 13, having a shape in which a cord length decreases and then increases from the tip of the second outer upstream fixed wing toward the second terminal end of the duct. In the developed view of one surface facing the outside of the duct,
14. The propulsion efficiency improving device of claim 13, wherein the curve defined by the leading edge of said duct has a single curvature. Among the plurality of upstream fixed blades, the first outer upstream stationary blade positioned last in the direction of rotation of the propeller and the second outer upstream fixed blade positioned last in the direction opposite to the direction of rotation of the propeller. 2. The propulsion efficiency improving device according to claim 1 , wherein an intermediate inner forestream fixed wing is positioned forward of said first outer foremost fixed wing and said second outer foremost fixed wing. The inner front flow stationary blade has one or more pieces,
The tip of the inner front fixed wing fixed to the inner surface of the duct has a front end positioned rearward of the leading edge of the duct and a rear end positioned forward of the trailing edge of the duct. 18. The propulsion efficiency improving device according to 17 . The inner front fixed wing, the first outer front fixed wing, and the second outer front fixed wing have the same cord length at the root, and all have the same cord length at the tip. ,
The front-rear distance between the inner front fixed wing and the first outer front fixed wing and the second outer front front fixed wing is 0.05 times or more the cord length of the root of the inner front fixed wing and 0.15. 18. The propulsion efficiency improving device according to claim 17 , which is twice or less.

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