DE202009002642U1 - Device for reducing the power requirement of a ship - Google Patents

Abstract

Device for reducing the drive power requirement of a single or multiple screw vessel, in particular for complete and non-complete, not very fast ships, characterized in that at a small distance from the propeller (101) on the hull (100) mounted device (10) a pre-nozzle (20) having fins (30; 30a, 30b, 30c, 30d) disposed within the pre-nozzle, the pre-nozzle preferably being up to 8 ° about a horizontal, transverse axis passing through the pre-nozzle center , is rotatable at the top to the front.

Description

The The invention relates to a device for reducing the power requirement a single or multiple screw vessel, in particular for complete and not complete, not very fast Ships.

From the DE 42 23 570 C1 is a flow guide for variable pitch propeller known. In the case of this flow-guiding surface, it is provided that a flow influencing is carried out by means of an upstream annular nozzle as a diffuser. For this purpose, a delay of the flow in the vicinity and an acceleration of the flow in the outer region is performed. The diffuser diameter is less than 65% of the propeller diameter. Such a nozzle is designed as a delay nozzle or as a diffuser with outwardly curved annular nozzle. This diffuser delays the flow in its area, which can only lead to an improvement of the Propulsionswirkungsgrades by very thick hubs, as with variable pitch propellers. Such a nozzle is therefore not designed as an acceleration nozzle with a curvature of the annular nozzle to the inside. Therefore, the nozzle presented in this document does not accelerate the flow in their area and is not suitable for all propeller types, especially not suitable for fixed propellers. An operating principle of a pre-nozzle, which consists in increasing the propeller flow velocity in areas of very high Mitstromes is in the DE 42 23 570 C1 not described.

From the JP 07 267189 A is a propeller assembly with an annular nozzle and star-shaped fins known. The propeller diameter corresponds approximately to the ring diameter of the nozzle.

In the JP 58 000492 A a further propeller arrangement is shown, with which an improvement of the efficiency and a reduction of the power requirement is to be possible. This arrangement also includes fins and a structure consisting of six honeycombed elements.

task the present invention is to provide a device that of reducing the power requirement of a ship serves. In addition, an improvement in efficiency and an adaptation of the fins or wings to the flow be achieved. In addition, the propeller inflow is to be improved become.

Solved This object is achieved by a device with the characteristics of Claim 1.

hereafter is the device according to the invention in the way formed that at a small distance in front of the propeller Attached to the hull device from a pre-nozzle with arranged within the pre-nozzle fins or wings where the pre-nozzle is about a horizontal, transverse axis, which passes through the Vordüsenmittelpunkt, preferably up to 8 °, can be rotated forwards.

With such a device, it is possible to reduce the power requirement of a ship. The possible Profit increases as the thrust load of the propeller increases. The device is particularly suitable for slow, complete Ships, like tankers, bulkers and tugs and not for either very fast ships of all types. The device itself is present the propeller of the ship firmly attached to the hull and consists of the two functional elements pre-nozzle and Fins or wings.

there is the principle of action of the pre-nozzle in the increase the propeller approach speed in areas very high Mitstromes and reduction of Propelleranströmgeschwindigkeit in areas of low Mitstromes and that in the pre-nozzle arranged fins or hydrofoils in the generation of a Vordralls, where both functional elements on different sources of loss aim, namely the pre-nozzle to a reduction the effective thrust load and the fins or wings on a reduction of the swirl losses in the propeller jet. By Both effects increase the efficiency of the propulsion system.

Thereby, that the device as close as possible in front of the propeller attached, will have the highest possible impact achieved, even with different loading cases.

in addition comes that the device of the invention is not only suitable for complete ships; she can for all not very fast ships, about V ≤ 25 K kn, be used with equal effect. Also an insert for very large container ships is possible.

Further advantageous embodiments are the subject of the dependent claims.

Around to achieve the highest possible impact is the Device or the pre-nozzle with its trailing edge is not further than 0.3 times the diameter of the propeller in front of the propeller plane appropriate. Preferably, the pre-nozzle is about 4 ° behind rotatable at the front.

To In a further embodiment, the pre-nozzle is a vertical one Axis passing through the center of the pre-nozzle, laterally so rotatable that the pre-nozzle on the upward beating side of the propeller is rotatable forward.

The Invention also provides that the pre-nozzle about a vertical Axis passing through the center of the pre-nozzle, laterally by up to 3 °, preferably by 1 °, so rotatable is that the pre-nozzle on the upwards beating side of the propeller is rotatable forward, the Rotation can also be 0 °, but not in the other direction.

Further the invention provides that the thickness of the profile of the pre-nozzle less than 12% of its length. advantageously, The thickness of the profile of the pre-nozzle can be 7.5% or 9% of its Length amount.

A Another embodiment provides that the fins or wings have in the radial direction a variable angle of attack, wherein the fins or wings are so twisted (twisted), that the fins or wings inside the ship upwards are directed and the angle of attack to the outside to the pre-nozzle decreases.

So the pre-nozzle is rotationally symmetric with upward shifted preferably arranged above the axis of the propeller axis, wherein the inner diameter of the pre-nozzle maximum 90% of the propeller diameter is.

preferably, four fins or wings are asymmetrically inside the pre-nozzle and arranged radially to the propeller axis, wherein the fins or wings the hull connect with the pre-nozzle and at the rear end of the pre-nozzle are arranged, with the curved side of the wing-shaped and also lenticular cross-sectional profile of the fin or the wing on the upward beating Side of the propeller up and down the down Side of the propeller is directed downwards. The arrangement of four fins or wings in the interior of the pre-nozzle However, this is not a restriction, especially since a smaller or larger number of fins or wings can be provided.

In The drawings are exemplary embodiments of a Ship with a propeller turning over to starboard the device of the invention shown and that shows:

1 in a side view of starboard the inventive device consisting of a pre-nozzle with arranged in the interior of fins or wings existing device,

2 the device in a view from the rear, wherein the fins or wings are shown not employed,

3 an enlarged cross section through the profile of a fin or a wing;

4 a side view of the rear contour,

5 a frame crack of the rear,

6 the pre-nozzle with arranged in their interior fins or wings according to 1 with positions of the fins,

7 a side view of the device with 4 ° tilted forward tilted front nozzle,

8th a perspective view of the pre-nozzle with inwardly upwardly directed and twisted (twisted) fins on the ship,

9 a diagram of power savings when using the device according to the invention,

10 a diagram of the power requirement with or without the device according to the invention and

11 a diagram of power savings when using the device according to the invention in various types of ships.

According to 1 there is the device according to the invention 10 in that immediately before the propeller, not shown in the drawing of a hull 100 a pre-nozzle 20 is provided with a cylindrical shape or egg ner differently shaped shape or cross-sectional shape, which is fixedly mounted on the hull. In the interior 20a the pre-nozzle 20 are fins or wings 30 arranged. The pre-nozzle 20 is rotationally symmetric with the axis shifted upwards 21 arranged on the hull.

At the in 2 illustrated embodiment are in the interior 20a the pre-nozzle 20 four fins or wings 30a . 3015 . 30c . 30d arranged in a star shape with different fin or wing lengths. These four fins or wings are arranged asymmetrically within the pre-nozzle and radially to the propeller axis PA. The fins or wings connect 30a . 30b . 30c . 30d the pre-nozzle 20 with the hull 100 and are at the rear end of the nozzle facing the propeller 20 arranged, with the curved side 32 the wing-shaped or lenticular cross-sectional profile 31 the fins or wings 30 . 30a . 30b . 30c . 30d directed down on the port side of the ship or on the upward-beating side of the propeller up and on the starboard side of the ship or down-facing side of the propeller. The fins or wings 30a . 30b . 30c . 30d are also forward port side forward and starboard front down directed ( 2 and 3 ). The direction of rotation of the propeller is in the direction of arrow X ( 1 ). The one in the interior 20a the pre-nozzle 20 arranged fins or wings 30 respectively. 30a . 30b . 30c . 30d are adjustable in their angular positions and lockable in the set angle positions.

According to one embodiment, with over propeller rotating to starboard take the fins or wings 30a . 30b . 30c . 30d following, preferred radial angular positions and initial angular positions: fin angle angle of attack Port (BB) lower fin ( 30a ) 247.5 ° 14 ° Port (BB) middle fin ( 30b ) 292.5 ° 12 ° Port (BB) upper fin ( 30c ) 337.5 ° 8 ° Starboard (SB) Fin ( 30d ) 90.0 ° 10 ° with a fin angle definition: seen from the rear: 12 o'clock = 0 o, increasing in a clockwise direction, whereby the fin angle and the angle of attack can deviate from the specified values.

After the in 1 . 3 and 6 illustrated embodiment, the fins or wings have a lenticular cross-sectional profile 31 with a curved side wall 32 and with a rectilinear footprint 33 on. The arrangement and position of, for example, the two fins 30 to the propeller axis PA is such that the upper fin with its base 33 is approximately parallel to the propeller axis PA, whereas the lower fin occupies a position in which its base 33 is running at an angle α of at least 5 °, preferably of 10 ° to the propeller axis PA. Other angular positions of the fins are possible. Overall, preferably have the fins 30a . 30b . 30c . 30d in the 2 shown positions.

The pre-nozzle 20 according to 1 and 6 is formed by a molding 25 with a cross-sectional profile 26 with an outside, at an angle to the propeller axis PA inclined wall section 26a and with an inner rectilinear and parallel to the propeller axis PA extending wall portion 26b in the area facing away from the propeller an arcuate wall section 26c having, in the outside wall portion 26a passes. The outside wall section 26a may also be arcuate. The propeller side is at PS in 6 indicated.

As 7 shows is the device 10 at a short distance in front of the propeller 101 on the hull 100 appropriate. The device 10 should be as close as possible in front of the propeller 101 be arranged. The pre-nozzle 20 is about a horizontal, transverse axis, which extends through the Vordüsenmittelpunkt, preferably by up to 8 °, rotatable above forward, arranged. In the 7 is the pre-nozzle 20 4 ° tilted forwards. Here is the pre-nozzle 20 with its trailing edge no further than 0.3 times the diameter of the propeller fixed in front of the propeller plane.

The pre-nozzle 20 may further be about a vertical axis which passes through the nozzle center laterally, for. B. up to 3 °, be rotated so that the pre-nozzle on the upward-beating side of the propeller 101 is turned forward. Optimal turns seem to be up to 1 °. Even 0 ° may be correct, but not in the other direction.

The thickness of the profile of the pre-nozzle 20 is less than 12% of its length. Preferably, the thickness of the profile of the pre-nozzle 20 7.5% or 9% of its length.

The fins or wings 30 . 30a . 30b . 30c . 30d have in the radial direction a variable angle of attack, the fins or wings are so twisted (twisted) that the fins or wings are directed inside the ship up and the angle of attack to the outside to the pre-nozzle 20 decreases ( 8th ).

The thickness configuration of the profile of the pre-nozzle 20 and the embodiment that the fins or wings 30 . 30a . 30b . 30c . 30d have a variable angle of attack in the radial direction, are essential for fast ships; they are also applicable to complete ships.

Due to the inventive design of the device 10 will receive significant power savings, as shown in the diagram of the 9 Making the power savings by using the device 10 for three ships, as can be seen in two ships with different draft (X = draft speed).

The diagram according to 10 shows the power requirements of a 118,000 DWT bulk carrier with and without the device 10 ,

Particularly high profits are z. B. in ships with 12,000 DWT due to a thick hub in a variable pitch propeller, their losses through the device 10 be reduced.

The level of protection is particularly high in very large slow ships. The diagram of 11 shows the power savings by the device 10 depending on the C _Th value. In the lower part of the 11 is given an assignment to ship types.

The device according to the invention is characterized by the features specified in the description and the claims and by the in the 1 to 11 the drawings illustrated embodiments.

10

contraption

20

prenozzle

20a

inner space

21

axis the pre-nozzle

25

moldings

26

Cross-sectional profile

26a

wall section

26b

wall section

26c

wall section

30

Fin / Hydrofoil

30a

Fin / Hydrofoil

30b

FlosselTragflügel

30c

Fin / Hydrofoil

30d

Fin / Hydrofoil

31

Cross-sectional profile

32

domed Side wall

33

Floor space

100

hull

101

propeller

BB

port

SB

starboard

PA

propeller axis

PS

propeller page

X

direction of rotation of the propeller

α

angle

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 4223570 C1 [0002, 0002]
• JP 07267189 A [0003]
• - JP 58000492A [0004]

Claims (13)

Device for reducing the power requirement of a single or multiple screw vessel, in particular for complete and non-complete, not very fast vessels, characterized in that at a small distance in front of the propeller ( 101 ) on the hull ( 100 ) attached device ( 10 ) from a pre-nozzle ( 20 ) with within the pre-nozzle arranged fins or wings ( 30 ; 30a . 30b . 30c . 30d ), wherein the pre-nozzle is rotatable about a horizontal, transverse axis, which extends through the Vordüsenmittelpunkt, preferably by up to 8 °, top to front. Apparatus according to claim 1, characterized in that the device or pre-nozzle ( 20 ) with its trailing edge not more than 0.3 times the diameter of the propeller is fixed in front of the propeller plane. Device according to one of claims 1 or 2, characterized in that the pre-nozzle ( 20 ) is rotatable about 4 ° above the front. Device according to one of claims 1 to 3, characterized in that the pre-nozzle ( 20 ) is laterally rotatable about a vertical axis that passes through the Vordüsenmittelpunkt that the pre-nozzle ( 20 ) on the upwardly striking side of the propeller ( 101 ) is rotatable forward. Apparatus according to claim 4, characterized in that the pre-nozzle ( 20 ) about a vertical axis that passes through the Vordüsenmittelpunkt laterally by up to 3 °, preferably by 10, is rotatable so that the pre-nozzle ( 20 ) on the upwardly striking side of the propeller ( 101 ) is rotatable forward. Device according to one of the preceding claims 1 to 5, characterized in that the thickness of the profile of the pre-nozzle ( 20 ) is less than 12% of its length. Device according to claim 6, characterized in that that the thickness of the profile of the pre-nozzle 7.5% or 9% of its Length is. Device according to one of the preceding claims 1 to 7, characterized in that the fins or wings ( 30 ; 30a . 30b . 30c . 30d ) have a variable angle of attack in the radial direction, wherein the fins or wings are twisted so that the fins or wings are directed inside the ship upwards and the angle of attack to the outside to the pre-nozzle ( 20 ) decreases. Device according to one of the preceding claims 1 to 8, characterized in that the pre-nozzle ( 20 ) with an inner diameter which is smaller than 90% of the propeller diameter, rotationally symmetrical with an upwardly shifted axis, preferably above the propeller axis (PA) ( 21 ) is arranged. Device according to one of the preceding claims 1 to 9, characterized in that preferably four fins or wings ( 30 ; 30a . 30b . 30c . 30d ) asymmetrically in the interior ( 20a ) of the pre-nozzle ( 20 ) and radially to the propeller axis (PA) are arranged, wherein the fins or wing the hull with the pre-nozzle ( 20 ) and at the rear end of the pre-nozzle ( 20 ) are arranged, wherein the curved side ( 32 ) of the lenticular cross-sectional profile ( 31 ) of the fin or of the wing ( 30 ; 30a . 30b . 30c . 30d ) is directed upwards on the upturning side of the propeller and downwards on the descending side of the propeller. Device according to one of the preceding claims 1 to 10, characterized in that the fins or wings ( 30 ; 30a . 30b . 30c . 30d ) assume the following preferred radial angular positions and initial angular positions: fin angle angle of attack Port (BB) lower fin ( 30a ) 247.5 ° 14 ° Port (BB) middle fin ( 30b ) 292.5 ° 12 ° Port (BB) upper fin ( 30c ) 337.5 ° 8 ° Starboard (SB) Fin ( 30d ) 90.0 ° 10 ° Device according to one of the preceding claims 1 to 11, characterized in that in the interior ( 20a ) of the pre-nozzle ( 20 ) arranged fins or wings ( 30 ) are changeable or adjustable in their angular positions. Use of a device ( 100 ) with the features of claims 1 to 12 for reducing the power requirement of a ship, especially for slow, complete and nichtvöllige ships, such as tankers, bulkers or tugs and for not very fast ships of all types, and to improve the propeller inflow and to produce a Vordralles.