JPH0733797U - Propeller with wing tip plate - Google Patents

Abstract

(57) [Summary] [Structure] The wing tip 4 of each wing 2 contracts rearwardly and has the surface F of the rotation of the wing 2 formed by the water passing through the propeller disk A. Is formed into an arc 5 having a predetermined width with a geometrical shape that corresponds to the surface of the convoluted conical vein B, and over the entire arc width,
A propeller with a wing tip plate integrally provided with a wing tip plate 8 projecting axially on the rear surface side of the wing 2. [Effect] The optimum diameter of the propeller can be made smaller, which reduces the weight and inertia of the propeller and helps reduce the cost. Propeller efficiency is higher, thrust is stronger. The maneuverability of the ship can be improved. Reduces cavitation, vibration and noise.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a propeller with a wing tip plate, which is used, for example, in a ship and has a wing tip plate extending in the axial direction at each wing tip of a plurality of blades.

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, in propellers used for ships, propellers provided with accessories at the wing tips have been known to improve propeller efficiency and reduce fuel consumption. Among them, the blade tip has a large width to the blade tip in order to dilute the blade load distribution in the radial direction by sharing a large load, and in this case, the blade rear surface (high pressure By preventing the flow from flowing from the blade tip to the blade front surface (low pressure surface) and impairing the load bearing capacity, and by avoiding the generation of blade tip vortex by this flow. For the purpose of improving propeller efficiency and preventing cavitation, propellers with wing tip plates are known in which wing tip plates are attached to each wing tip in the axial direction.

To explain this more specifically, in the normal propeller 15 shown in FIG. 8, in order to make the blade surface load distribution so that the load at the blade tip becomes zero, the blade width at the blade tip 16 is reduced. Is gradually reduced so that the width at the tip 17 becomes zero (point). On the other hand, in the propeller 21 with a wing tip plate shown in FIG. 9, the wing tip 22 also has a large wing width so that the wing tip 22 can also receive a load, and thus operates as expected. If so, the load distribution on the blade surface is thinned in the radial direction, so that the propeller size is reduced and the propeller efficiency is increased. When the blade tip 22 also has a large width in this manner, the blade tip 23 is also loaded, that is, high pressure is also generated at the blade tip. In order to prevent the loss of pressure and the generation of tip vortices (that is, cavitation) due to the flow from the blade rear surface (high pressure surface) 24 to the blade front surface (low pressure surface) 25 in 23, the rear surface of each blade tip 23. A wing tip plate 26 projecting in the axial direction is provided over the entire width.

As shown in FIGS. 10 and 11, the outer peripheral surface 26a of each of the blade end plates 26 is concentric with the propeller shaft center 28 with the propeller disk (propeller rotating circle) 27 as a vertical surface. It conforms to the surface of the cylindrical shape 29 that extends in the axial direction.

In such a propeller 21 with a wing tip plate, there is a problem in that the viscous resistance of the wing tip plate 26 tends to increase and tends to occur. In order to reduce this viscous resistance, it is necessary to make the flow of water passing through the propeller 21 with blade end plate into the cylindrical shape 29 described above so that the inflow of water to the blade end plate 26 is shock-free. is there. For this reason, in the conventional propeller with a wing tip plate as described above, the propeller with a wing tip plate 21 is placed in a cylindrical duct provided on the hull, or in front of the propeller with a wing tip plate. A nozzle is provided on the hull so that the flow vein of water passing through the propeller disk 27 has a cylindrical shape 29.

[0006]

[Problems to be solved by the device]

 However, as described above, providing ducts or nozzles on the hull as an indispensable condition raises costs and requires a long construction period. Therefore, when the conventional propeller 21 with a wing tip plate is operated independently in open water without providing these ducts or nozzles, there are the following problems. That is, when the propeller 21 with a wing tip plate is operated in open water, the flow vein of water passing through the propeller disk 27 has a conical shape that contracts rearward, and the surface surrounding the flow vein rotates. It has been known. On the other hand, in the blade tip plate 26 of the conventional propeller 21 with blade tip plates, the trajectory plane when it rotates matches the cylindrical surface that passes through the propeller disk 27, so that water is transferred to the blade trailing surface ( At the high-pressure surface 24, as the blade tip plate 26 moves relative to the front end toward the rear end, a position shift occurs between the blade tip plate 26 and the water stream. As a result, the flow of water to the wing tip plate 26 does not become shock-free, the viscous resistance increases, and as the water moves toward the rear end side of the wing tip plate 26, the flow separation occurs, and the wing tip plate 26 induces an induced expansion in the flow, reducing the pressure acting on the wing surface. That is, the load (that is, thrust) bearing capacity at the blade tip 22 is reduced, and the load cannot be effectively diluted and distributed in the radial direction of the blade. Therefore, there was a problem that the propeller efficiency was lower than the expected value.

According to the present invention, in a propeller with a wing tip attached to the wing tip, even if the propeller is operated in open water without providing a duct or nozzle on the hull, the viscous resistance is minimized at the wing tip plate portion. Moreover, it is possible to effectively distribute the pressure even at the blade tip without separating the flow and induced expansion for the flow, that is, to effectively dilute the blade load distribution in the radial direction. In addition, it is possible to achieve a propeller efficiency that is as high as that expected for a propeller with tip plates, and to provide a propeller with tip plates that can minimize cavitation, noise, and vibration. With the goal.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, the propeller with a wing tip plate of the present invention is a propeller with a wing tip plate in which a wing tip plate axially projecting is attached to each wing tip of a plurality of blades. And its tip is a conical, converging rearwardly swirling surface where the trajectory plane as it rotates is formed by the water passing through the propeller disk. The blade is formed into an arc having a predetermined width with a geometrical shape corresponding to the surface of the vein, and a wing tip plate axially projecting on the rear surface side of the blade is integrally provided over the entire width of the arc.

In a preferred embodiment of the present invention, in the propeller with a wing tip plate, the wing tip plate is made to have a geometric shape such that the trajectory plane when the wing tip plate rotates also matches the surface of the flow vein. ing.

Still another preferred embodiment of the present invention is the above propeller with blades, in which a conical duct having the same contraction angle as the flow vein is provided concentrically on the outer circumference of the propeller. There is.

[0011]

[Action]

 According to the configuration of the present invention described above, in the open water as described above, the stream of water flowing through the propeller disk (rotating circle) has a conical shape that contracts rearward. The water molecules that first come into contact with the front end point of the arc move relative to the blade surface along the rear surface of the blade due to the rotation of the blade, leave the surface of the blade after reaching the rear end point of the arc, and move absolutely backward. At this time, since the blade end plate, that is, the rotation trajectory surface formed by the rotation of the blade tip arc, coincides with the conical surface of the vein, the inflow of water to the arc front end point becomes shock-free and the water flows into the blade. When moving backwards along the plane, the vector of this movement coincides with the plane of the rotation trajectory of the tip plate, so there is no separation of the flow by the tip plate and there is an induced expansion ( That is, a pressure drop) does not occur.

At this time, the pressure generated at the blade tip is confined on the blade surface by the blade plate, and the flow escapes from the blade tip of the rear surface of the high pressure side to the blade front side (that is, the pressure is It lowers).

From the above, pressure (that is, thrust) can be distributed even to the blade tip at the blade rear surface, and the load distribution on the blade surface is diluted in the radial direction. In other words, the radial distribution of circulation in the blade is set to a constant value from the position away from the axial center to the blade tip by 0.6 times the radius R of the propeller disk (rotation circle), and the thrust is transmitted from the propeller boss to the blade. The distribution can be continuously increased up to the end, so that high propeller efficiency can be obtained and the propeller size can be reduced.

Furthermore, since there is no escape from the blade tip on the blade rear surface to the blade front surface side, blade tip vortices are not generated, and therefore cavitation does not occur and the propeller is not eroded. Furthermore, the load (pressure) distribution on the blade surface is diluted in the radial direction, so the pressure exerted by the propeller on the hull is also reduced, and vibration and noise can be reduced.

[0015]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. 1 and 2, the blades 2 of the propeller 1 with a blade end plate are to be obtained with the required pitch and curved surface shape. That is, the blade 2 extends from the propeller boss 3 in the radial direction, and its width gradually increases as it advances from the propeller boss 3 in the radial direction, and then gradually decreases after reaching the maximum width portion or gradually increases to the blade tip 4. to continue. In any case, even if it reaches the blade tip 4, it has a sufficient width.

The shape and dimensions of the blade 2 are such that the radial distribution of circulation in the blade 2 is 0.6 times the radius of the propeller disk (rotating circle) of the propeller 1 with a blade end plate from the axial center, as shown in FIG. By maintaining a constant value from the distant position to the blade tip 4, high propeller efficiency is obtained.

It should be noted that FIG. 5 compares the radial distribution of the propeller blades according to the present invention in the radial direction of the blade circulation with that of the conventional type propeller 15 (FIG. 8) and the conventional propeller 21 with a blade end plate (FIG. 9). Is shown. From FIG. 5, not only in the normal-type propeller 15 but also in the conventional propeller 21 with a wing tip plate, the flow separation at the wing tips as described above ・ The radial distribution of circulation to the wing tips due to the pressure drop The propeller efficiency cannot be increased to the value expected for the propeller with tip plates compared to the propeller 1 with tip plates of the present invention, and the propeller dimensions are also expected. It turns out that it is not possible to reduce the value.

The blade tip arc 5 of each blade tip 4 has a trajectory plane when the blade tip 4 rotates, which is generated by the operation of the propeller 1 with a blade tip plate in open water. It is formed in a geometrical shape that conforms to the surface of the conical vein B that contracts backwards through. As a result, when the blade tip arc 5 rotates, the rotating circle at the arc trailing end point 7 becomes smaller than the rotating circle at the arc leading end point 6 by the amount of contraction of the blood stream B. On the outer circumference of the blade tip arc 5 of each blade 2, a blade tip plate 8 that extends in the axial direction with a small length is provided on the rear surface side of the blade 2 over the entire arc length in conformity with the tip shape of the blade tip arc 5. Provide each integrally.

Note that the angle formed between the blade end plate 8 and the blade surface may be a right angle as in the present embodiment, or as shown in FIG. That is, even if the angle is slightly smaller than a right angle, the axial length of the blade tip plate 8 is relatively small, and therefore the performance is hardly affected.

The operation of the above configuration will be described below. Microscopically looking at the action of the blade surface on water at the blade tip portion 4, in FIG. 7, the water molecule C that first comes into contact with the arc front end point 6 appears on the blade surface along the blade rear surface 9 due to the rotation of the blade 2. And moves away from the blade surface after reaching the rear end point 7 of the arc. At this time, assuming an ideal state where there is no friction (viscous) resistance, the water molecule C absolutely moves backward with the vector D indicated by the alternate long and short dash line shown in FIG. (And, the reaction force acts on the propeller blade surface and becomes the pressure on the blade surface, and becomes the propeller thrust.) However, in reality, such an ideal state does not exist, and the water molecule C is shown in FIG. Absolutely move backward with vector E of the dotted line. The water molecules C aggregate to form a vein B as a whole. That is, the blood stream B is contracted rearward by the vector E, and is swirled in the propeller rotation direction. Since the rotation trajectory plane F formed by the rotation of the blade tip plate 8, that is, the blade tip arc 5, coincides with the conical surface of the flow vein B, the arc front end point 6 of the portion of the blade tip plate 8 is reached. The inflow of water is shock-free, and when the water moves rearward along the blade surface, the vector of this movement coincides with the rotation trajectory plane F of the blade plate 8, so the blade plate No separation of the flow by 8 occurs and no induced expansion (ie pressure drop) occurs in the flow.

At this time, the pressure generated at the blade tip 4 is confined on the blade surface by the blade tip plate 8, and the flow diverts from the blade tip 4 of the blade rear surface 9 on the high pressure side to the blade front surface 10 side. (That is, the pressure drops) is prevented.

From the above, the pressure (that is, thrust) can be distributed to the blade tip 4 at the blade rear surface 9, and the load distribution on the blade surface is diluted in the radial direction. That is, as shown in FIG. 5, the radial distribution of the circulation in the blade 2 becomes a constant value from the position separated from the axial center by 0.6 times the radius R of the propeller disk (rotating circle) A to the blade tip 4. In this way, by providing a distribution in which the thrust increases continuously from the propeller boss 3 to the blade tip 4, high propeller efficiency can be obtained and the propeller size can be reduced.

Further, as described above, since there is no escape from the blade tip 4 of the blade rear surface 9 to the blade front surface 10 side, a blade tip vortex is not generated, therefore cavitation does not occur and the propeller is crushed. Never eaten. In addition, the load (pressure) distribution on the blade surface is diluted in the radial direction, so the pressure exerted by the propeller on the hull is also reduced, and vibration and noise are reduced.

In the above embodiment, the case where the propeller 1 with wing tip plate is used as a propeller of a ship and the fixed pitch propeller is explained, but the propeller 1 with wing tip plate of the present invention is The same effects can be obtained when applied to propellers other than thrusters such as bow thrusters and nozzle propellers, as well as variable pitch propellers.

In addition, in the above-mentioned embodiment, it is an object to provide a propeller 1 with a wing tip plate that can exhibit desired performance even in open water without providing a duct or nozzle on the hull. However, if the propeller 1 with wing tip plate of the present invention is operated in a conical duct having the same contraction angle as the flow vein B, it cannot be escaped in open water. It is possible to obtain a further increase in thrust without any slight dissipation of the flow energy in the stream B of B. Therefore, the propeller efficiency can be further increased and the propeller size can be further reduced.

[0026]

[Effect of device]

 According to the propeller with wing tip plate of the present invention having the above configuration, the following outstanding effects are exhibited.

(1) The optimum diameter of the propeller becomes smaller. The optimum diameter of the propeller can be made smaller than that of the conventional type propeller as well as the conventional propeller with a tip plate, thus reducing the weight and inertia of the propeller as well as helping to reduce the cost.

(2) Propeller efficiency is higher and thrust is stronger. Due to the high efficiency of propellers, when a ship is operated at a constant speed, fuel consumption is reduced by more than 10% compared to the case of a normal type propeller (or when the fuel consumption is constant, the ship speed is reduced). Improvement) is obtained. In addition, thrust becomes stronger, and for fishing boats and tugboats that require particularly large thrust, the towing force will increase by 12% or more compared to the case of a normal type propeller. In this case, a large towing force can be obtained by combining with a nozzle.

(3) The maneuverability of the ship can be improved. Compared to the normal type propeller, the pressure behind the propeller is stronger and a strong wake is generated up to the blade tip, which improves the rudder effect generated by the wake. That is, the steering efficiency improves, the response speed (turning speed of the ship) increases, and the turning radius also decreases. In addition, the time and coasting distance can be shortened when the ship suddenly stops due to steering.

(4) Cavitation, vibration and noise are reduced. Since the tip plate does not generate tip vortices, cavitation does not occur, and therefore the propeller does not erode. In addition, the pressure (load) distribution on the propeller blade surface is diluted in the radial direction, so that the pressure applied to the hull is considerably smaller than in the case of a normal type propeller, and vibration and noise are reduced.

[Brief description of drawings]

FIG. 1 is an external perspective view of a propeller with wing end plates as seen from the rear and from below, showing an embodiment of the present invention.

FIG. 2 is a front view of a main part of the propeller with the wing end plate.

FIG. 3 is a schematic diagram illustrating a geometrical shape of the blade tip plate (blade tip arc).

FIG. 4 is an explanatory view in which a portion M of FIG. 1 is partially broken and a model is added.

FIG. 5 is an explanatory diagram comparing propeller circulation distributions.

FIG. 6 is an explanatory view of another embodiment of the M portion of FIG. 1 with a partial cutaway and a model added.

7 is an explanatory diagram of a relationship between rotation of the blade of FIG. 1 and a flow of water.

FIG. 8 is an external perspective view of a normal propeller as viewed from the rear and from below.

FIG. 9 is an external perspective view of a conventional propeller with wing end plates as viewed from the rear and from below.

FIG. 10 is a schematic diagram illustrating a geometrical shape of the blade tip plate (blade tip arc).

FIG. 11 is an explanatory view in which a part is cut away in the N portion of FIG. 9 and a model is added.

[Explanation of symbols]

 1 Propeller with wing tip plate 2 wing 3 propeller boss 4 wing tip 5 wing tip arc 6 arc front end point 7 arc rear end point 8 wing tip plate 9 wing rear surface (high pressure surface) 10 wing front surface (low pressure surface) A propeller disk B (cone Shape of flow vein C Water molecule D Ideal vector E Actual vector F Rotation plane of blade tip plate (blade tip arc)

Claims (3)

[Scope of utility model registration request] 1. A propeller with a wing tip plate having a wing tip plate extending axially at each wing tip of a plurality of blades, wherein each wing comprises:
While extending radially from the propeller boss, its wing tip has a conical shape whose trailing surface, when it is rotated, contracts backwards and swirls the surface where the water passing through the propeller disk forms. It is characterized in that it is formed into an arc having a predetermined width with a geometric shape that matches the surface of the flow vein, and a wing end plate that axially projects on the rear surface side of the wing is integrally provided over the entire width of this arc. Propeller with wing tip plate. 2. The propeller with a wing tip plate according to claim 1, wherein the wing tip plate has a geometric shape such that a trajectory plane when the wing tip plate rotates also matches a surface of the flow vein. 3. A propeller with a wing tip plate according to claim 1, wherein the propeller is provided with a conical duct having the same contraction angle as that of the flow vein, concentrically on the outer circumference of the propeller.