JPH1143096A - Propeller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize the reduction in propeller efficiency and keep the strength of a propeller wing by setting the wing width of a propeller wing end in a prescribed range, continuously changing the rake distribution, and setting the rake backward on the wing end side from a prescribed position. SOLUTION: A wing width 6 in a wing end 5 of a propeller wing 1 is set to 10-30% of the propeller radius. The rake distribution is continuously changed so that the rake is set on the front side to the propeller base line on a wing root 4 side, and the rake is set on the rear side on the wing end 5 side, and a position 7 of an inflection point is set in the position of 80% or more of the propeller radius. Consequently, the strength of a secondary flow generated from the face surface in the wing end 5 part toward the back surface is reduced to keep the pressure difference between the back surface and face surface in the wing end 5 part, so that the reduction in propeller efficiency can be minimized according to the reduction in thrust. Further, since the rake distribution of the propeller is continuously changed, stress concentration can be avoided, and the strength can be kept.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propeller which can be applied, for example, as a marine propeller.

[0002]

FIG. 13 is a side view of a main part of a conventional propeller having a linear rake distribution, FIG. 14 is a front view of the conventional propeller of FIG. 13, and FIG. FIG. 16 is a side view of a main part of a conventional propeller having a rear rake at an end side, and FIG. 16 is a side view of a main part of a conventional propeller having a rear rake at a blade root side and a front rake at a wing end side;
(1) is a main part side view showing a secondary flow flowing from the rear side to the front side of the propeller at the tip of the conventional propeller,
FIG. 17 (2) is a front view of the main part of the propeller of FIG. 17 (1).

[0003] Conventionally, as a propeller having a wing width 6 at the tip of the propeller blade 1 finite, for example, a propeller used for a side thruster or an impeller of a nozzle propeller is generally used, and is used as a propulsion device for an ordinary ship. As shown in FIGS. 13 and 14, the profile of the propeller blade of the propeller is a continuous curve up to the blade tip, and the blade width 6 at the blade tip is generally zero.

On the other hand, the rake distribution is changed linearly in the forward or rearward direction as shown in FIG. 13 from the viewpoint of maintaining the strength of the propeller blade, or as the maximum blade thickness section 3 in FIG. As shown, propeller wing 1
At the blade root 4 side, a rake is taken forward with respect to the propeller bus perpendicular to the center line of the propeller boss 2, and at the wing tip 5 side, a rake is taken backward with respect to the propeller bus, and the rake distribution is The position 7 of the inflection point is set to a position of 40 to 70% of the propeller radius, or as shown as the maximum blade thick section 3 in FIG. 16, the blade root 4 side of the propeller blade 1 is A rake on the wing tip 5 side and a rake forward with respect to the propeller bus, and a propeller whose inflection point 7 in the rake distribution is positioned at 40 to 70% of the propeller radius. General.

A propeller having a blade width 6 of a propeller blade tip 5 of zero and adopting the above-mentioned distribution as a rake distribution is employed for the purpose of reducing stress concentration on the blade surface from the viewpoint of propeller strength. And does not have the propeller shape considered for propeller efficiency.

By the way, looking at the pressure distribution on the wing surface of the propeller blade, the pressure on the wing surface facing the front side of the propeller, that is, the back surface, is usually higher than the pressure on the wing surface facing the rear side of the propeller, that is, the face surface. , And the pressure difference gives the propeller forward thrust.

Normally, on the blade surface of the propeller blade, as shown by an arrow 8 in FIGS. 17 (1) and 17 (2), a width in a blade width direction from the leading edge side to the trailing edge side of the propeller blade is shown. Flow occurs, but at the wing tip 5, as shown by the arrow 9, the wing tip 5 is moved from the face face to the back face of the wing in a direction substantially perpendicular to the flow shown by the arrow 8. A passing secondary flow occurs. This is because, since the pressure on the back surface is lower than the pressure on the face surface, a flow occurs from a high pressure portion to a low portion, that is, from the face surface side to the back surface side.

[0008]

The secondary flow as shown by the arrow 9 generated at the wing tip 5 reduces the pressure difference between the back surface and the face surface, so that the thrust generated at the wing tip 5 is reduced. And the propeller efficiency decreases accordingly.

Therefore, the present invention is capable of suppressing the secondary flow from the face surface of the wing to the back surface through the wing tip, and by doing so, the back surface and the face surface at the wing tip can be reduced. The pressure difference between the propellers to prevent a decrease in propeller thrust, thereby reducing the loss of propeller efficiency and at the same time avoiding stress concentrations on the propeller blades. It is an object of the present invention to provide a propeller capable of maintaining the strength of a propeller blade.

[0010]

In order to solve the above-mentioned problems, in the propeller of the present invention, the blade width at the tip of the propeller blade is 10 to 30% of the radius of the propeller, and the rake distribution of the propeller blade changes continuously. Specifically, the rake is taken from the position more than 80% of the propeller radius to the wing tip side more backward than the rake at the propeller radius position closest to the blade root side from the same position.

Further, in the propeller of the present invention, the blade width at the tip of the propeller blade is 10 to 30% of the radius of the propeller, and the rake distribution of the propeller blade is continuously changed. On the wing tip side, a rake is taken on the rear side, and the point of inflection is the propeller radius of 8
0% or more.

Further, in the propeller of the present invention, the blade width of the propeller blade tip is 10 to 30% of the propeller radius,
The rake distribution of the propeller blades is continuously changing. The rake is taken rearward from the blade root side to the wing tip side, and there is an inflection point at a position of 80% or more of the propeller radius. On the wing tip side, the rear rake is larger than the rear rake on the blade root side from the inflection point.

Further, in the propeller of the present invention, the blade width at the tip of the propeller blade is 10 to 30% of the radius of the propeller, and the rake distribution of the propeller blade changes continuously, and the rake distribution has two inflection points. The wing root side has a rake on the rear side, and the first rake is located at 40 to 70% of the propeller radius.
From the inflection point to the forward rake, and the rake is taken rearward on the wing tip side from the second inflection point at a position 80% or more of the propeller radius.

Further, in the propeller of the present invention, the blade width at the tip of the propeller blade is 10% or more of the radius of the propeller, the rake distribution of the propeller blade is continuously changed, and the rake amount is zero at the root of the blade. Turning the rake forward at 40-70% of the radius, 8% of the propeller radius
Rake is taken backward on the wing tip side from the inflection point at 0% or more.

[0015]

FIG. 1 is a side view of a main part of a propeller according to an embodiment of the present invention, FIG. 2 is a front view of a main part of the propeller of FIG. 1, and FIG. 3 (1) is a propeller at a tip of a propeller blade. Side view of the main part of the propeller showing the secondary flow flowing from the rear side to the front side, FIG. 3 (2) is a front view of the main part of the propeller of FIG. 3 (1), and FIG. 4 is a numerical value of the performance of the propeller of FIG. FIG. 5 is a front view of a calculation model used when calculation is performed, FIG. 5 is a side view of a calculation model used when calculating the performance of the propeller of FIG. 1 by numerical calculation, and FIG. 6 is a graph showing the propeller efficiency with respect to a change in propeller thrust. FIG. 7 is a graph showing the relationship between the propeller (solid line) according to the present invention and a conventional propeller (dotted line), FIG. 7 is a graph showing the relationship between the blade width of the propeller blade tip and propeller efficiency, and FIG. 8 is a rake distribution. Between the radial position of the inflection point and the propeller efficiency Is a graph showing the engagement.

In FIGS. 1 and 2, the blade width 6 at the blade tip 5 of the propeller blade 1 is 10 to 30% of the propeller radius, and the rake distribution of the propeller blade 1 is continuously changed. Is raked forward with respect to the propeller bus perpendicular to the center line of the propeller boss 2 and raked rearward on the wing tip side, and the inflection point 7
Are located at 80% or more of the propeller radius.

According to the present invention, the strength of the secondary flow as shown by the arrow 9 generated from the face surface to the back surface at the tip 5 of the propeller blade 1 shown in FIG.
Because it is weaker than the secondary flow of the conventional propeller shown in Fig. 7,
The pressure difference between the back surface and the face surface at the wing tip 5 is maintained, the reduction in thrust can be reduced, and the reduction in propeller efficiency can be reduced.

In order to compare the efficiency of the propeller according to the present invention with that of a conventional propeller, calculations were made by the panel method. The propeller calculation model used to calculate the efficiency of the propeller of the present invention is as shown in FIG. 4 and FIG. The propeller calculation model of the present invention shown in FIGS. 4 and 5 is a four-wing propeller.

In FIG. 6, the efficiency of the propeller of the present invention shown by the solid line graph is higher over a wide range of propeller thrust than the efficiency of the conventional propeller shown by the dotted line graph. That is, the propeller of the present invention becomes a propeller with high propeller efficiency over a wide range of propeller thrust. According to the propeller of the present invention, as a marine propulsion device,
In a normally used propeller thrust state, that is, in a normal propeller operation state, a higher propeller efficiency can be obtained than a conventional propeller.

Since the rake distribution of the propeller of the present invention is changed continuously, stress concentration can be avoided as compared with the case where a rake distribution having discontinuous points is used.
Strength is maintained.

FIG. 7 shows the relationship between the blade width 6 of the propeller blade tip 5 and the propeller efficiency. When the blade width 6 of the propeller blade tip 5 is 10% or more of the propeller radius, a large improvement in propeller efficiency can be expected. The shape of the propeller blade tip 5 may be either linear or arc-shaped, but such a propeller blade tip 5
The range of the blade width 6 of the propeller blade tip 5 where the effect of improving the propeller efficiency of the propeller blade having
It is about 10% to 30% of the propeller radius. When the blade width 6 of the propeller blade tip 5 in this range of preferably 15 to 25% is adopted, the inflection point position 7 of the rake needs to be 80% or more of the propeller radius. FIG. 8 shows the relationship between the rake inflection point position 7 and the propeller efficiency. When the rake inflection point position 7 is 80% or more of the propeller radius,
An improvement in propeller efficiency can be expected.

As shown in FIG. 7, the blade width 6 of the propeller blade tip 5 is set in a range of 10 to 30% of the propeller radius. As shown in FIGS. 1 and 2, the rake distribution changes continuously,
The change is that the forward rake is taken on the blade root side 4 and the rear rake is taken on the wing tip side 5, and as shown in FIG. 8, the inflection point 7 is at least 80% of the propeller radius, preferably 85%. %, The propeller efficiency can be expected to be improved, and stress concentration on the propeller blades can be avoided, and the strength can be maintained.

A propeller in which the blade width 6 of the propeller blade tip 5 is set to 10% or less of the propeller radius, or a change in the rake distribution is continuous, and the change takes a forward rake on the blade root 4 side, and the blade tip 5 On the side of the propeller, the rake is taken backward, and the inflection point 7 is set to a position of 80% or more of the propeller radius.

The propeller of the present invention has a rake distribution opposite to the direction of the rake distribution, that is, the blade width 6 of the propeller blade tip 5 is 10 to 30% of the propeller radius, and the rake distribution changes continuously. In the case of a propeller with a rear rake on the wing root side 4 and a forward rake on the wing tip side 5 and the inflection point 7 located at a position of 80% or more of the propeller radius, the wing tip The cavitation often occurs on the back surface in the above, and the danger of cavitation erosion increases.

FIG. 9 is a side view of a propeller according to a second embodiment of the present invention, and FIG. 10 is a side view of a main part showing a distance relationship between a propeller blade tip and a hull. In the propeller of FIG. 9, the blade width of the propeller blade tip 5 is set to 10 times the propeller radius.
３０30%, the rake distribution of the propeller blades is continuously changing, the rake is taken rearward from the blade root side to the wing tip side, and there is an inflection point at a position of 80% or more of the propeller radius, On the wing tip side of the inflection point, a rearward rake larger than the rearward rake on the blade root side of the inflection point is taken.

In FIG. 9, the intensity of the secondary flow generated from the face surface to the back surface at the propeller blade tip 5 is weaker than the secondary flow of the conventional propeller. And the pressure difference between the face and
The reduction in thrust can be reduced, and the reduction in propeller efficiency can be reduced. Therefore, efficiency can be expected to be improved as compared with the conventional propeller.

In the propeller shown in FIG. 9, in addition to the effect of the propeller shown in FIG. 1, the surface force induced on the hull surface by the rotation of the propeller becomes smaller than that of the propeller shown in FIG. . That is, as shown in FIG. 10, the distance 12 between the propeller blade tip 5 of the propeller of FIG. 9 and the hull 10 is larger than the distance 12 ′ between the propeller blade tip 5 and the hull 10 in the case of the propeller of FIG. Is also large. By reducing the surface force, it is possible to make the hull vibration smaller than in the case of the propeller of FIG.

FIG. 11 is a side view of a main part of a propeller according to a third embodiment of the present invention. In the propeller of FIG. 11, the blade width of the propeller blade tip 5 is 10 to 3 times the propeller radius.
0%, the rake distribution of the propeller blades changes continuously, and the rake distribution has two inflection points.
On the side, the rake is taken on the rear side, and from the first inflection point located at 40 to 70% of the propeller radius, it turns to the forward rake, and the second inflection point is located at 80% or more of the propeller radius. On the wing tip side from the inflection point, the rake is taken rearward.

In the propeller shown in FIG. 11, the strength of the secondary flow generated from the face surface to the back surface at the propeller blade tip 5 is weaker than the secondary flow of the conventional propeller. The pressure difference between the back surface and the face surface in the five portions is maintained, the decrease in thrust can be reduced, and the decrease in propeller efficiency can be suppressed.
As a result, the propeller of FIG. 11 can improve the propeller efficiency more than the conventional propeller.

In the propeller shown in FIG. 11, the position 7 of the inflection point on the blade root 4 side of the rake distribution is the same as the part of the rake distribution of the conventional propeller shown in FIG.
Since the position is set at 0 to 70%, stress concentration on the blade surface can be reduced. Therefore, the propeller of FIG. 11 is superior in propeller strength to the propeller shown in FIG. 1 and the propeller shown in FIG.

FIG. 12 is a side view of a main part of a propeller according to a fourth embodiment of the present invention. In the propeller shown in FIG. 12, the blade width of the propeller blade tip 5 is 10 to 30% of the propeller radius, the rake distribution of the propeller blade 1 is continuously changed, and the rake amount is zero at the blade root 4. The rake is turned forward at a position of 40 to 70% of the propeller radius, and is raked rearward on the wing tip side from an inflection point at a position 7 'at 80% or more of the propeller radius.

In the propeller of FIG. 12, the intensity of the secondary flow generated from the face surface to the back surface at the propeller blade tip 5 is weaker than the secondary flow of the conventional propeller. In this case, the pressure difference between the back surface and the face surface is maintained, and the decrease in thrust can be reduced, so that the decrease in propeller efficiency can be suppressed. Therefore, the propeller shown in FIG. 12 can greatly improve the propeller efficiency as compared with the conventional propeller.

In the propeller of FIG. 12, since the position 7 of the inflection point on the blade root side 4 of the rake distribution is 40 to 70% of the radius of the propeller similarly to the propeller of FIG. Concentration can be eased. Therefore, FIG.
Is superior in propeller strength to the propeller of FIG. 1 and the propeller of FIG. Further, since the rake amount is set to zero at the blade root portion 4, the propeller shape at the blade root portion 4 is simplified, and the processing of the propeller is facilitated.

[0034]

According to the propeller of the present invention, the following effects can be obtained. (1) The blade width at the tip of the propeller blade is 10 to 30 times the radius of the propeller.
%, And the rake distribution of the propeller blades changes continuously,
From the position 80% or more of the propeller radius to the wing tip side, the rake was taken rearward from the rake at the propeller radius position closest to the blade root side from the same position, so that the rake passed from the wing face to the wing tip. The secondary flow toward the back surface can be suppressed, the pressure difference between the back surface and the face surface at the wing tip can be kept large, and a decrease in thrust of the propeller can be prevented. As a result, the propeller can be prevented. Since the efficiency can be improved and the rake distribution of the propeller blades is continuously changed, stress concentration on the propeller blades can be avoided, and the strength of the propeller blades can be maintained (claim 1). (2) The blade width at the tip of the propeller blade is 10 to 30 times the radius of the propeller.
%, And the rake distribution of the propeller blades changes continuously,
On the wing root side, a rake is taken forward, and on the wing tip side, a rake is taken backward, and the inflection point is at a position of 80% or more of the propeller radius. It is possible to suppress the secondary flow passing through to the back surface, to maintain a large pressure difference between the back surface and the face surface at the wing tip, and to prevent a decrease in the thrust of the propeller. As a result, the propeller efficiency can be improved, and at the same time, the rake distribution of the propeller blades changes continuously.
By taking the rake on the rear side on the wing tip side,
Stress concentration on the propeller blade can be avoided, and the strength of the propeller blade is maintained (claim 2). (3) The blade width at the tip of the propeller blade is 10 to 30 times the radius of the propeller.
%, And the rake distribution of the propeller blades changes continuously,
A rake is taken rearward from the blade root side to the blade tip side, and there is an inflection point at a position of 80% or more of the propeller radius,
On the wing tip side from the inflection point, a larger rear rake was taken than the rear rake on the blade root side from the inflection point,
2 from the face of the wing to the back through the wing tip
The following flow can be suppressed, thereby maintaining a large pressure difference between the back surface and the face surface at the wing tip, preventing a decrease in propeller thrust and consequently improving propeller efficiency. At the same time, since the rake distribution of the propeller blades is continuously changing, stress concentration on the propeller blades can be avoided, the strength of the propeller blades can be maintained, and further from the blade root side to the blade tip side. By providing a rake on the rear side, the distance between the propeller wing tip and the hull can be kept large, and the surface force induced on the hull surface with the rotation of the propeller can be small. 3). (4) The blade width at the tip of the propeller blade is 10 to 30 times the radius of the propeller.
%, And the rake distribution of the propeller blades changes continuously,
It has two inflection points in the rake distribution, rakes rearward on the wing root side, and turns to forward rake from the first inflection point at 40-70% of the propeller radius,
A rake was taken rearward on the wing tip side from the second inflection point at 80% or more of the propeller radius, so the secondary flow from the wing face face to the back face through the wing tip was taken. The pressure difference between the back surface and the face surface at the wing tip can be kept large to prevent a decrease in the thrust of the propeller, and as a result, the propeller efficiency can be improved. At the same time, the rake distribution of the propeller blades is continuously changed, and the rake is taken rearward on the blade root side. From the first inflection point located at 40 to 70% of the radius of the propeller blade, the front rake is turned. With this change, stress concentration on the propeller blade surface can be largely prevented, and the strength of the propeller blade can be kept large (claim 4). (5) The blade width at the tip of the propeller is 10 to 30 times the radius of the propeller.
%, And the rake distribution of the propeller blades changes continuously,
At the root of the blade, the rake amount is set to zero, and the propeller radius
The rake was turned forward at the 0-70% position, and raked rearward on the wing tip side from the inflection point located at 80% or more of the propeller radius. The secondary flow passing through to the back surface can be suppressed, thereby maintaining a large pressure difference between the back surface and the face surface at the wing tip,
A reduction in the thrust of the propeller is prevented, and as a result, the propeller efficiency can be improved. Strength is maintained,
Further, since the rake amount is zero at the blade root portion, the propeller shape at the blade root portion is simplified, and the processing of the propeller is easy (claim 5).

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a propeller according to an embodiment of the present invention.

FIG. 2 is a front view of a main part of the propeller of FIG.

FIG. 3A is a side view of a main part of the propeller showing a secondary flow flowing from the rear side to the front side of the propeller at the tip of the propeller blade, and FIG. 3B is a front view of the main part of the propeller in FIG. FIG.

FIG. 4 is a front view of a calculation model used when the performance of the propeller of FIG. 1 is obtained by numerical calculation.

5 is a side view of a calculation model used when the performance of the propeller of FIG. 1 is obtained by numerical calculation.

FIG. 6 is a graph showing a change in propeller efficiency with respect to a change in propeller thrust in comparison with a propeller according to the present invention (solid line) and a conventional propeller (dotted line).

FIG. 7 is a graph showing a relationship between a blade width of a propeller blade tip and a propeller efficiency.

FIG. 8 is a graph showing a relationship between a radial position of an inflection point of a rake distribution and a propeller efficiency.

FIG. 9 is a side view of a propeller according to a second embodiment of the present invention.

FIG. 10 is a main part side view showing a distance relationship between a propeller wing tip and a hull.

FIG. 11 is a side view of a main part of a propeller according to a third embodiment of the present invention.

FIG. 12 is a side view of a main part of a propeller according to a fourth embodiment of the present invention.

FIG. 13 is a side view of a main part of a conventional propeller having a linear rake distribution.

FIG. 14 is a front view of the conventional propeller of FIG.

FIG. 15 is a side view of a main part of a conventional propeller in which a blade root side has a front rake and a blade tip side has a rear rake.

FIG. 16 is a side view of a main part of a conventional propeller having a rear rake on a blade root side and a front rake on a blade tip side.

17 (1) is a side view of a main part showing a secondary flow flowing from the rear side to the front side of the propeller at the tip of the blade of the conventional propeller, and FIG. 17 (2) is the propeller of FIG. 17 (1). FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Propeller blade 2 Propeller boss 3 Maximum wing section of propeller blade 4 Blade root 5 Blade tip 6 Blade width of propeller blade tip 7 Position of inflection point of rake distribution 7 'Second variation on wing tip side of rake distribution Position of the bend point 8 Arrow indicating the direction of flow flowing in the wing width direction from the leading edge side to the trailing edge side on the wing surface 9 Secondary flow flowing from the face surface to the back surface at the propeller blade end 10 Hull 11 Rudder 12 Propeller Distance between wingtip and hull

Claims (5)

[Claims] 1. The blade width at the tip of a propeller blade is one of the radius of the propeller.
0 to 30%, and the rake distribution of the propeller blade is continuously changed. From the position of 80% or more of the propeller radius to the blade tip side, compared to the rake at the propeller radius position closest to the blade root side from the same position. A propeller characterized by a rearward rake. 2. The blade width at the tip of the propeller blade is equal to one of the radius of the propeller.
0 to 30%, the rake distribution of the propeller blades changes continuously, the rake is taken forward on the blade root side, the rake is taken rearward on the wing tip side, and the inflection point is A propeller characterized by being located at a position of 80% or more of a radius. 3. The blade width at the tip of the propeller blade is one of the radius of the propeller.
0 to 30%, the rake distribution of the propeller blades changes continuously, the rake is taken rearward from the blade root side to the wing tip side, and there is an inflection point at a position 80% or more of the propeller radius. A propeller characterized by having a larger rearward rake on the wing tip side than the inflection point and a rearward rake on the blade root side than the inflection point. 4. A blade width of a propeller blade tip is one of a propeller radius.
0 to 30%, the rake distribution of the propeller blade is continuously changed, the rake distribution has two inflection points, and the wing root has a rake on the rear side, and the propeller radius is 40 to
The rake turned from the first inflection point at 70% to the forward rake, and raked rearward on the wing tip side from the second inflection point at 80% or more of the propeller radius. A propeller. 5. The blade width at the tip of the propeller blade is one of the radius of the propeller.
0 to 30%, the rake distribution of the propeller blades is continuously changed, the rake amount is zero at the blade root, the rake is turned forward at a position of 40 to 70% of the propeller radius, and the propeller radius is 80%. A propeller characterized by a rearward rake on the wing tip side from the inflection point at a position of more than%.