DK2885203T3 - RING SCREW WITH PREVENTION - Google Patents

RING SCREW WITH PREVENTION Download PDF

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Publication number
DK2885203T3
DK2885203T3 DK13753301.4T DK13753301T DK2885203T3 DK 2885203 T3 DK2885203 T3 DK 2885203T3 DK 13753301 T DK13753301 T DK 13753301T DK 2885203 T3 DK2885203 T3 DK 2885203T3
Authority
DK
Denmark
Prior art keywords
ring
screw
propeller
thruster
blade
Prior art date
Application number
DK13753301.4T
Other languages
Danish (da)
Inventor
Terje Jahn Johannessen
Original Assignee
Rolls-Royce Marine As
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rolls-Royce Marine As filed Critical Rolls-Royce Marine As
Application granted granted Critical
Publication of DK2885203T3 publication Critical patent/DK2885203T3/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H1/00—Propulsive elements directly acting on water
    • B63H1/02—Propulsive elements directly acting on water of rotary type
    • B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
    • B63H1/14—Propellers
    • B63H1/16—Propellers having a shrouding ring attached to blades
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H1/00—Propulsive elements directly acting on water
    • B63H1/02—Propulsive elements directly acting on water of rotary type
    • B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
    • B63H1/14—Propellers
    • B63H1/26—Blades
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/12—Use of propulsion power plant or units on vessels the vessels being motor-driven
    • B63H21/17—Use of propulsion power plant or units on vessels the vessels being motor-driven by electric motor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
    • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
    • B63H5/125—Arrangements on vessels of propulsion elements directly acting on water of propellers movably mounted with respect to hull, e.g. adjustable in direction, e.g. podded azimuthing thrusters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B2241/00—Design characteristics
    • B63B2241/02—Design characterised by particular shapes
    • B63B2241/10—Design characterised by particular shapes by particular three dimensional shapes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
    • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
    • B63H5/125—Arrangements on vessels of propulsion elements directly acting on water of propellers movably mounted with respect to hull, e.g. adjustable in direction, e.g. podded azimuthing thrusters
    • B63H2005/1254—Podded azimuthing thrusters, i.e. podded thruster units arranged inboard for rotation about vertical axis
    • B63H2005/1258—Podded azimuthing thrusters, i.e. podded thruster units arranged inboard for rotation about vertical axis with electric power transmission to propellers, i.e. with integrated electric propeller motors

Description

DESCRIPTION
[0001] The present invention relates to a ring propeller and a thruster comprising a ring propeller which is driven by a permanent magnet motor.
[0002] This type of thruster with a ring propeller driven by means of a permanent magnet motor is employed on different types of vessels. Known permanent magnet-driven ring propellers, however, have been designed without much skew.
[0003] The French document FR 68 426 E discloses a ring propeller for a thruster comprising a ring, a centre element and propeller blades extending between the centre element and the ring. Figure 1 of the publication indicates that the propeller blades may be provided with a forward skew although the description does not mention it. The leading edge has a slight bulge in the middle which is rounded, for example with an elliptical shape. This rounded shape of the blades allows, according to the description, for an improved attack in the water and increases the width of the blades in the zone of the blade of optimal work. The rounded shape of the leading edge means that a middle portion of the blade is the portion of the blade that will first meet water with changed speed, i.e. the middle portion of the blade meets zones in the water of changed speed earlier than the outer portion of the blade.
[0004] In developing the present ring propeller and thruster which are driven by a permanent magnet motor, an object has been to provide a permanent magnet-driven thruster with greater efficiency than known thrusters.
[0005] It has been a further object to provide a permanent magnet-driven thruster vwth a ring propeller which offers better control of when cavitation sets in and the extent of the cavitation.
[0006] These objects are achieved with the present ring propeller as defined in claim 1, a thruster as defined in claim 6 and an application of the ring propeller as defined in claim 7. Further embodiments of the ring propeller are defined in claims 2-5.
[0007] A ring propeller is provided for a thruster. The ring propeller comprises a ring, a centre element and at least one propeller blade extending between the centre element and the ring and attached to the centre element and the ring. The propeller blade has a leading edge profile and a trailing edge profile and is provided with forward skew. The leading edge profile of the at least one propeller blade, moreover, has an S-shape in a cross section perpendicular to the ring propeller's axis of rotation with a concave shape in a portion at a point of attachment to the ring such that a tangent to the leading edge profile at the point of attachment to the ring propeller's encompassing ring and the tangent to the encompassing ring at the same attachment point form an angle which is greater than 0° and less than 90°.
[0008] The at least one propeller blade's trailing edge profile may also have an S-shape in a cross section perpendicular to the ring propeller's axis of rotation. The combination of the S-shape on the at least one propeller blade's leading edge profile and possibly trailing edge profile and the forward skew of the at least one propeller blade provide better cavitation conditions, i.e. reduced cavitation.
[0009] The leading edge has a leading edge profile viewed in a section perpendicular to the ring propeller's axis of rotation. Correspondingly, the propeller blades' trailing edge will then naturally be the edge on the opposite side of the propeller blade with a trailing edge profile viewed in a section perpendicular to the ring propeller's axis of rotation. The fact that the ring propeller's blades have a forward skew means that the propeller tip, which is attached to the ring, is skewed forwards towards the propeller's normal direction of rotation, with the result that the outermost part of the blade meets zones with altered speed earlier. In connection with the forward skew of the propeller blades, a skew angle can be defined. The skew angle is the greatest possible angle, viewed in a cross section perpendicular to the ring propeller's axis of rotation, measured between the straight line drawn from the point where the propeller blade's centre chord line/skew line meets the ring propeller's encompassing ring and the axis of rotation and a line tangential to a point on the propeller blade's centre chord line and the axis of rotation. The propeller blade's centre chord line and the skew angle of a propeller blade on the present ring propeller are shown in the attached figures.
[0010] In an embodiment of the invention the S-shaped trailing edge profile may also have a concave shape in a portion at the point of attachment to the ring. In the same way as above, this means that the tangent to the trailing edge profile at the point of attachment to the ring propeller's encompassing ring and the tangent to the encompassing ring at the same attachment point form an angle which is greater than 0° and less than 90°.
[0011] With regard to the strength of the blades, they have preferably been given a thickened shape (a fillet) in the transition to the propeller ring. By employing a concave shape on the outermost part of the blades, space is provided for a slimmer fillet and thereby better hydrodynamic conditions on the outermost part of the propeller.
[0012] In an embodiment of the present invention the ring propeller's ring is preferably provided with permanent magnets, where the permanent magnets form a part of a permanent magnet motor when the ring propeller is mounted in the thruster.
[0013] A thruster is also provided comprising a ring propeller and a permanent magnet motor. The thruster comprises a ring propeller as described above and a thruster housing which encloses the ring propeller's ring and comprises the permanent magnet motor's stator windings. A permanent magnet motor is thereby provided for driving the ring propeller. The thruster's ring propeller is otherwise preferably designed as described above and may advantageously be used on a vessel.
[0014] A non-limiting embodiment of the present invention will now be described with reference to the figures, in which
Figure 1 is a cross section of a thruster with a ring propeller according to the present invention perpendicular to the ring propeller's axis of rotation A.
Figure 2 illustrates the same figure as above, but where the angles between the ring and the leading edge profile and the trailing edge profile respectively are indicated.
[0015] Figure 1 illustrates a thruster 10 according to the present invention. The thruster 10 comprises a thruster housing 13 and a ring propeller 12 which may be rotatably mounted in the thruster housing 13 about the axis of rotation A. The ring propeller 12 comprises a ring 15 and a centre element 16. Between the ring 15 and the centre element 16 a number of propeller blades 18 are preferably mounted, attached to the centre element 16 and the ring 15. The ring propeller 12 is therefore a monoblock where the propeller blades 18 have fixed pitch. The thruster 10 is arranged for attachment to a vessel (not shown in the figures). For this purpose the thruster 10 may be provided with an attachment element 17, thereby enabling the thruster 10, for example, to be screwed, bolted or welded to the vessel.
[0016] The ring propeller 12 further comprises permanent magnets (not shown in the figures) which are preferably mounted in the ring 15. In the thruster housing 13 stator windings (not shown in the figure) are similarly provided, with the result that the ring propeller is driven by a permanent magnet motor. Electric power for the permanent magnet motor may, for example, be supplied via the attachment element 17.
[0017] The propeller blades 18 have a leading edge profile 19 and a trailing edge profile 20 in a section perpendicular to the ring propeller's 12 axis of rotation A as indicated in figure 1. The leading edge profile 19 and the trailing edge profile 20 are defined in relation to the ring propeller's 12 direction of rotation R as illustrated in figure 1.
[0018] The propeller blades 18 have an imaginary centre chord line 24 extending from the centre element 16 to a point 27 where the centre line intersects the ring 15. The centre chord line 24 is the imaginary line located at the same distance from the leading edge profile 19 as from the trailing edge profile 20 on the propeller blade 18.
[0019] As indicated in the figures, the propeller is designed with forward skew, i.e. the propeller blades 18 are skewed forwards in the direction of the propeller's normal direction of rotation R, with the result that the outermost part of the blade meets zones with changed speed earlier. The degree of forward skew may be indicated by means of the skew angle V. The skew angle V is the greatest angle formed between a first line 25 through the axis of rotation A and a point 27 where the centre line 24 crosses the ring's 15 internal diameter and a second line 26 through the axis of rotation A and a point 28 on the centre line 24. Depending on the propeller blade's degree of forward skew, the point 28 on the centre line may vary. In figure 1 the point 28 on the centre line 24 which will give the greatest angle, i.e. the skew angle V, is right in at the centre element 16. In other designs the point 28 may be located somewhere on the centre line between the centre element 16 and the ring 15. By providing the ring propeller 12 with forward skew in this manner, the ring propeller 12 will acquire better cavitation properties since the tip of the propeller blades 18 takes a smaller part of the total thrust.
[0020] As illustrated in the figures the propeller blades' 18 leading edge profile 19 is designed with a slight S-shape. This means that in the transition to the ring 15, it will be possible to design the propeller blades 18 with a slim section, giving a good hydrodynamic effect while at the same time providing sufficient strength. The trailing edge profiles may also be designed with a slight S-shape as indicated in the figures.
[0021] In the transition between the propeller blades' leading edge profile 19 and the ring 15, the propeller blades 18 preferably have a concave shape. This is illustrated in greater detail in figure 2 where the tangent 30 to the propeller blade's leading edge profile 19 in the attachment point 37 and the tangent 31 to the ring 15 in the attachment point 37 to the ring are indicated. Due to the fact that the propeller blades 18 have a concave shape, the angle 35 opening on to the ring is less than 90° and greater than 0°.
[0022] In a similar manner, in the transition between the propeller blades' trailing edge 19 and the ring 15, the propeller blades 18 preferably have a concave shape. This is also illustrated in figure 2 where the tangent 32 to the propeller blade's trailing edge profile 20 in the attachment point 38 and the tangent 33 to the ring's 15 attachment point 38 to the ring are indicated. Due to the fact that the propeller blades 18 have a concave shape, the angle 36 opening on to the ring is also less than 90° and greater than 0°.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.
Patent documents cited in the description • PR68426E [0003]

Claims (7)

1. Ringskrue (12) til en thruster (10), hvilken ringskrue (12) omfatter en ring (15), et centerelement (16) og mindst ét skrueblad (18), der strækker sig mellem og er fastgjort til henholdsvis centerelementet (16) og ringen (18), hvilket mindst ene skrueblad (18) har en forkantsprofil (19) og en bagkantsprofil (20) i et tværsnit vinkelret på ringskruens (12) rotationsakse A, hvor det mindst ene skrueblad (18) er tilvejebragt med foroverhældning, kendetegnet ved, at den yderste del af bladet (18) møder områder med ændret hastighed hurtigere, og ved, at forkantsprofilen (19) af det mindst ene skrueblad (18) har en S-form med en konkav fonn i en del ved et fastgørelsespunkt (37) til ringen (18), således at en tangent til forkantsprofilen ved fastgørelsespunktet til ringskruens omsluttende ring og tangenten til den omsluttende ring ved det samme fastgørelsespunkt danner en vinkel, der er større end 0° og mindre end 90 °.A ring screw (12) for a thruster (10), said ring screw (12) comprising a ring (15), a center member (16) and at least one screw blade (18) extending between and attached to the center member (16, respectively). ) and the ring (18), which at least one screw blade (18) has a leading edge profile (19) and a trailing edge profile (20) in a cross-section perpendicular to the axis of rotation of the ring screw (12), where the at least one screw blade (18) is provided with forward slope , characterized in that the outermost part of the blade (18) meets areas with altered speed more rapidly, and in that the leading edge profile (19) of the at least one screw blade (18) has an S-shape with a concave shape in a part at a attachment point (37) to the ring (18) such that a tangent to the leading edge profile at the attachment point of the ring screw enclosing ring and the tangent to the enclosing ring at the same attachment point form an angle greater than 0 ° and less than 90 °. 2. Ringskrue ifølge krav 1, kendetegnet ved, at det mindst ene skrueblads (18) bagkantsprofil (20) har en S-form i et tværsnit vinkelret på ringskruens (12) rotationsakse A.Ring screw according to claim 1, characterized in that the rear edge profile (20) of the at least one screw blade (18) has an S-shape in a cross section perpendicular to the axis of rotation of the ring screw (12). 3. Ringskrue ifølge krav 2, kendetegnet ved, at i en del af skruebladet (18), ved bagkantens fastgørelsespunkt (38) til ringen (15), det mindst ene skrueblads S-fonnede bagkantsprofil (20) har en konkav form.Ring screw according to claim 2, characterized in that in a part of the screw blade (18), at the point of attachment of the rear edge (38) to the ring (15), the at least one screw blade S-shaped rear profile (20) has a concave shape. 4. Ringskrue ifølge et af kravene 1-3, kendetegnet ved, at ringskruens ring (15) er forsynet med permanentmagneter, hvilke permanentmagneter udgør en del af en permanentmagnetmotor, når ringskruen (12) er monteret i thrusteren (10).Ring screw according to one of claims 1-3, characterized in that the ring screw (15) of the ring screw is provided with permanent magnets, which permanent magnets form part of a permanent magnet motor when the ring screw (12) is mounted in the thruster (10). 5. Ringskrue ifølge et af kravene 1-4, kendetegnet ved, at ringskruen (12) er en monoblok, hvor skruebladene (18) har fast skruestigning.Ring screw according to one of Claims 1 to 4, characterized in that the ring screw (12) is a monoblock with the screw blades (18) having a fixed screw pitch. 6. Thruster (10), der omfatter en ringskrue (12) og en permanentmagnetmotor, kendetegnet ved, at thrusteren (10) omfatter en ringskrue (12) ifølge et af kravene 1-6 og et thrusterhus (13), der indeslutter ringskruens (12) ring (15), og som omfatter permanentmagnetmotorens statorviklinger.Thruster (10) comprising a ring screw (12) and a permanent magnet motor, characterized in that the thruster (10) comprises a ring screw (12) according to one of claims 1-6 and a thruster housing (13) enclosing the ring screw ( 12) ring (15), comprising the stator windings of the permanent magnet motor. 7. Anvendelse af en ringskrue (12) ifølge et af kravene 1-5 i en thruster (10) på et fartøj, hvor ringskruen (12) drives af en permanentmagnetmotor.Use of a ring screw (12) according to one of claims 1-5 in a thruster (10) on a vessel, wherein the ring screw (12) is driven by a permanent magnet motor.
DK13753301.4T 2012-08-14 2013-08-13 RING SCREW WITH PREVENTION DK2885203T3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO20120899A NO335877B1 (en) 2012-08-14 2012-08-14 Ring propeller with forward twist
PCT/EP2013/066925 WO2014026993A1 (en) 2012-08-14 2013-08-13 Ring propeller with forward screw

Publications (1)

Publication Number Publication Date
DK2885203T3 true DK2885203T3 (en) 2017-05-01

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Family Applications (1)

Application Number Title Priority Date Filing Date
DK13753301.4T DK2885203T3 (en) 2012-08-14 2013-08-13 RING SCREW WITH PREVENTION

Country Status (14)

Country Link
US (1) US20150210370A1 (en)
EP (1) EP2885203B1 (en)
JP (1) JP6158331B2 (en)
KR (1) KR102112493B1 (en)
BR (1) BR112015003246A2 (en)
DK (1) DK2885203T3 (en)
ES (1) ES2621905T3 (en)
HK (1) HK1209708A1 (en)
HR (1) HRP20170565T1 (en)
NO (1) NO335877B1 (en)
PL (1) PL2885203T3 (en)
PT (1) PT2885203T (en)
RU (1) RU2628625C2 (en)
WO (1) WO2014026993A1 (en)

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AU2021246540A1 (en) * 2020-04-02 2022-12-08 Open Inductions Pty Ltd Fluid drawing induction motor

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Also Published As

Publication number Publication date
RU2015106853A (en) 2016-10-10
HK1209708A1 (en) 2016-04-08
US20150210370A1 (en) 2015-07-30
RU2628625C2 (en) 2017-08-21
JP6158331B2 (en) 2017-07-05
WO2014026993A1 (en) 2014-02-20
EP2885203A1 (en) 2015-06-24
NO20120899A1 (en) 2014-02-17
PT2885203T (en) 2017-04-24
ES2621905T3 (en) 2017-07-05
NO335877B1 (en) 2015-03-16
HRP20170565T1 (en) 2017-06-30
EP2885203B1 (en) 2017-02-15
KR102112493B1 (en) 2020-05-19
JP2015524771A (en) 2015-08-27
PL2885203T3 (en) 2017-07-31
BR112015003246A2 (en) 2017-07-04
KR20150043467A (en) 2015-04-22

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