US20140363298A1 - Diffuser-type endplate propeller - Google Patents

Diffuser-type endplate propeller Download PDF

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Publication number
US20140363298A1
US20140363298A1 US14/151,827 US201414151827A US2014363298A1 US 20140363298 A1 US20140363298 A1 US 20140363298A1 US 201414151827 A US201414151827 A US 201414151827A US 2014363298 A1 US2014363298 A1 US 2014363298A1
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US
United States
Prior art keywords
propeller
endplate
diffuser
type
hull
Prior art date
Legal status (The legal status 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 status listed.)
Abandoned
Application number
US14/151,827
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English (en)
Inventor
Young-Zehr Kehr
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
National Taiwan Ocean University NTOU
Original Assignee
National Taiwan Ocean University NTOU
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 National Taiwan Ocean University NTOU filed Critical National Taiwan Ocean University NTOU
Assigned to NATIONAL TAIWAN OCEAN UNIVERSITY reassignment NATIONAL TAIWAN OCEAN UNIVERSITY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KEHR, YOUNG-ZEHR
Publication of US20140363298A1 publication Critical patent/US20140363298A1/en
Priority to US15/860,685 priority Critical patent/US10155575B2/en
Abandoned legal-status Critical Current

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    • 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
    • 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

Definitions

  • the present invention generally relates to a propeller, and more particularly, to a diffuser-type endplate propeller.
  • tip vortex free (TVF) propeller and contracted loaded tip (CLT) propeller.
  • TVF tip vortex free
  • CLT contracted loaded tip
  • the endplate thereof is tangential to the cylindrical surface of the propeller blade-tip. That is during the rotation of the propeller, the endplate becomes a portion of the cylindrical surface to reduce the viscous resistance of the endplate.
  • the successive developers further make the endplate contracted by design, i.e., for the new designed CLT propeller, the leading edge radius of the endplate is greater than the radius of the trailing edge.
  • both the TVF propeller and the CLT propeller are able to effectively prevent the fluid at the high-pressure side-surfaces of the propeller blades from flowing to the low-pressure side-surfaces so as to keep the loads of the blade-tips and suppress the intensity of the tip vortex. Accordingly, a quite portion of the thrust produced by the above-mentioned TVF propeller or CLT propeller is provided by the high-pressure side-surfaces of the propeller blades, which reduces the probability for the low-pressure side-surface of the propeller to produce cavitation.
  • Another more serious trouble is that if a CLT propeller is applied to a hull based on the inclined-shaft design, for example, a speedboat, the CLT propeller under an inclined-shaft inflow condition has a more serious cavitation phenomenon occurred at the endplate of a blade when the blade turns to the upper-vertical position.
  • the present invention is directed to a diffuser-type endplate propeller under an inclined-shaft inflow condition which can largely reduce even eliminate the sheet cavitation phenomenon produced by the endplates no matter the propeller blades turn to any angle positions.
  • An embodiment of the present invention provides a diffuser-type endplate propeller for driving a hull.
  • the diffuser-type endplate propeller includes a propeller hub and a plurality of blades.
  • the propeller hub is connected to a transmission shaft of the hull.
  • Each of blades respectively has a blade-body and an endplate connected to each other, wherein each of the blade-bodies is connected to the propeller hub and extends outward from the propeller hub to the corresponding endplate, each the endplate bends from the corresponding blade-body to extend towards the stern of the hull, each of the endplates has a leading edge and an trailing edge, each the leading edge keeps a first distance from the axis of the propeller hub, each the trailing edge keeps a second distance from the axis of the propeller hub, and the first distance is less than the second distance.
  • the above-mentioned diffuser-type endplate propeller is configured to drive the hull for proceeding towards a sailing direction, wherein the axis of the propeller hub is not parallel to the sailing direction.
  • the above-mentioned blades are disposed and radially arranged on the propeller hub.
  • the above-mentioned diffuser-type endplate propeller is integrally molded.
  • the above-mentioned angle of attack is ⁇ 1°.
  • the endplate propeller of the invention is a diffuser-type endplate propeller, i.e., when the diffuser-type endplate propeller is rotating, it does not produce sheet cavitation phenomenon at the endplates, so that the invention improves the efficiency of the endplate propeller and reduces the hull vibration and noise.
  • FIG. 1 is a schematic partial diagram showing a diffuser-type endplate propeller connected to a hull in an embodiment of the invention.
  • FIG. 2 is a three-dimensional diagram of the diffuser-type endplate propeller of FIG. 1 .
  • FIG. 3 is a front-view diagram of the diffuser-type endplate propeller in FIG. 1 in the angle of view towards the stern of the hull.
  • FIG. 4 is a diagram showing the diffuser-type endplate propeller of FIG. 2 in clockwise rotating.
  • FIG. 5A is a diagram showing the inflow velocity at the inclined-shaft for the diffuser-type endplate propeller of FIG. 1 .
  • FIG. 5B is a diagram showing the diffuser-type endplate propeller of FIG. 5A in clockwise rotating along the X axis.
  • FIG. 5C is a diagram showing the inflow velocity at the endplate for the diffuser-type endplate propeller of FIG. 5A , wherein the propeller turns to the 0° circumferential position.
  • FIG. 5D is a diagram showing the inflow velocity at the cylindrical endplate for a conventional propeller under an inclined-shaft inflow condition, wherein the propeller turns to the 0° circumferential position.
  • FIG. 5E is a diagram showing the inflow velocity at the endplate for the diffuser-type endplate propeller of FIG. 5A , wherein the propeller turns to the 180° circumferential position.
  • FIG. 5F is a diagram showing the inflow velocity at the cylindrical endplate for a conventional propeller under an inclined-shaft inflow condition, wherein the propeller turns to the 180° circumferential position.
  • FIG. 1 is a schematic partial diagram showing a diffuser-type endplate propeller connected to a hull in an embodiment of the invention
  • FIG. 2 is a three-dimensional diagram of the diffuser-type endplate propeller of FIG. 1
  • FIG. 3 is a front-view diagram of the diffuser-type endplate propeller in FIG. 1 in the angle of view towards the stern of the hull.
  • a diffuser-type endplate propeller 100 of the embodiment is able to drive a hull 20
  • the diffuser-type endplate propeller 100 includes a propeller hub 110 and a plurality of blades 120 .
  • the propeller hub 110 is connected to a transmission shaft 22 of the hull 20 .
  • Each of the blades 120 respectively has a blade-body 122 and a endplate 124 connected to each other, in which each the blade-body 122 is connected to the propeller hub 110 and extends outward from the propeller hub 110 to the corresponding endplate 124 , and each the endplate 124 bends from the corresponding blade-body 122 to extend towards a stern 24 of the hull.
  • Each the endplate 124 has a leading edge 124 a and an trailing edge 124 b, in which the leading edge 124 a keeps a first distance D1 from an axis L of the propeller hub 110 , the trailing edge 124 b keeps a second distance D2 from the axis L of the propeller hub 110 , and the first distance D1 is less than the second distance D2.
  • the diffuser-type endplate propeller 100 of the embodiment is installed, for example, at the bottom of the hull 20 and operated under an inclined-shaft condition.
  • the diffuser-type endplate propeller 100 is connected to an end of the transmission shaft 22 through the propeller hub 110 , while another end of the transmission shaft 22 is connected to the engine in the hull 20 (not shown).
  • the transmission shaft 22 is driven to rotate the diffuser-type endplate propeller 100 , and, by means of the rotating of the blades 120 , the water flow is back pushed towards the stern 24 so as to produce a forward reaction for driving the hull 20 to proceed in a sailing direction A2, in which the axis L of the propeller hub 110 is not parallel to the sailing direction A2.
  • the quantity of the blades 120 is two to six. In the embodiment, there are, for example, four blades 120 , which are disposed and radially arranged on the propeller hub 110 .
  • the diffuser-type endplate propeller 100 is fabricated in, for example, casting process by using metallic material or composite materials. In other words, the propeller hub 110 and the blades 120 can be integrally molded to have better rigidity to withstand the pressure of the water flow.
  • the blade-body 122 of a blade 120 can further include a high-pressure side-surface towards the stern 24 and a low-pressure side-surface back from the stern 24 , in which the most portion of the thrust produced by the diffuser-type endplate propeller 100 is provided by the high-pressure side-surface.
  • the diffuser-type endplate propeller 100 in the embodiment rotates clockwise and the endplates 124 can prevent the water flow moved by the rotations of the blades 120 from flowing to the low-pressure side-surfaces at the blade-tips so as to ensure the diffuser-type endplate propeller 100 having good efficiency and effectively suppress the tip vortex.
  • the leading edge 124 a is, for example, for guiding the water flow of the high-pressure side-surface of the propeller to flow to the trailing edge 124 b along the inner-side of the endplate 124 , and then, guiding the water flow out of the high-pressure side-surface through the trailing edge 124 b.
  • the endplate 124 of the embodiment chordwise extends to the trailing edge 124 b from the leading edge 124 a, in which the leading edge 124 a keeps a first distance D1 from the axis L, the trailing edge 124 b keeps a second distance D2 from the axis L, and the first distance D1 is less than the second distance D2, and further thus, the endplate 124 has a diffused shape chordwise.
  • FIG. 4 is a diagram showing the diffuser-type endplate propeller of FIG. 2 in clockwise rotating.
  • the rotating track of the leading edge 124 a forms a cylindrical surface S 1
  • a negative angle of attack (the diffuser angle) a is present between each the endplate 124 and the leading edge 124 a .
  • the leading edge 124 a and the cylindrical surface S 1 has a boundary line I 1
  • the endplate 124 is located at the boundary line I 1 and has a first section C 1 along the chord of the endplate 124
  • the cylindrical surface S 1 has a second section C 2 on the boundary line I 1
  • the included angle of the first section C 1 and the second section C 2 is just the above-mentioned angle of attack ⁇ .
  • the above-mentioned angle of attack ⁇ is, for example, ⁇ 1°, which means the endplate 124 of the embodiment has a negative angle of attack.
  • FIG. 5A is a diagram showing the inflow velocity at the inclined-shaft for the diffuser-type endplate propeller of FIG. 1 .
  • FIG. 5B is a diagram showing the diffuser-type endplate propeller of FIG. 5A in clockwise rotating along the X axis.
  • FIG. 5C is a diagram showing the inflow velocity at the endplate for the diffuser-type endplate propeller of FIG. 5A , wherein the propeller turns to the 0° circumferential position.
  • FIG. 5D is a diagram showing the inflow velocity at the cylindrical endplate for a conventional propeller under an inclined-shaft inflow condition, wherein the propeller turns to the 0° circumferential position.
  • FIG. 5A is a diagram showing the inflow velocity at the inclined-shaft for the diffuser-type endplate propeller of FIG. 1 .
  • FIG. 5B is a diagram showing the diffuser-type endplate propeller of FIG. 5A in clockwise rotating along the X axis.
  • FIG. 5E is a diagram showing the inflow velocity at the endplate for the diffuser-type endplate propeller of FIG. 5A , wherein the propeller turns to the 180° circumferential position.
  • FIG. 5F is a diagram showing the inflow velocity at the cylindrical endplate for a conventional propeller under an inclined-shaft inflow condition, wherein the propeller turns to the 180° circumferential position.
  • the actual experiments prove when the diffuser-type endplate propeller 100 rotates under an inclined-shaft condition, the diffuser-type endplate 124 not only prevents the water flow of the high-pressure side-surface from flowing to the low-pressure side-surface, but also eliminates the sheet cavitation phenomenon produced by the endplates 124 no matter the propeller blades 120 turn to any angle positions.
  • the axis L of the propeller hub 110 has an inclined-shaft angle ⁇ towards the sailing direction A2 of the hull, in which the inclined-shaft angle ⁇ ranges, for example, between 8° and 12°, and the propeller is suitable for a high-speed boat such as a speedboat.
  • the hull 20 in sailing produces a propeller inflow V1, in which the propeller inflow V1 enters the diffuser-type endplate propeller 100 in a direction opposite to the sailing direction A2, and the propeller inflow V1 has an included angle towards the axis L, i.e. the inclined-shaft angle ⁇ .
  • the propeller inflow V1 can be resolved into a first inflow component V1 cos ⁇ parallel to the axis Land a second inflow component V1 sin ⁇ vertical to the axis L.
  • the second inflow component V1 situp enables the endplate 124 turning to the 0° circumferential position to increase the actual angle of attack or to the 180° circumferential position to decrease the actual angle of attack.
  • the diffuser-type endplate propeller 100 rotates in a peripheral velocity ⁇ R around the X axis, wherein the peripheral velocity ⁇ R1 produces an opposite cylindrical tangential inflow velocity ⁇ R1 and the peripheral velocity ea is equal to the cylindrical tangential inflow velocity ⁇ R1.
  • the cylindrical tangential inflow velocity ⁇ R1 and the second inflow component V1 sin ⁇ together form a first actual angle of attack ⁇ 1 produced by the inclined-shaft inflow at the endplate 124 .
  • the cylindrical tangential inflow velocity ⁇ R1 and the second inflow component V1 sin ⁇ together form a first cylindrical endplate angle of attack ⁇ 11 produced by the inclined-shaft inflow at the cylindrical endplate 220 , in which the first cylindrical endplate angle of attack ⁇ 11 is positive.
  • the cylindrical tangential inflow velocity ⁇ R1 and the second inflow component V1 sin ⁇ together form a second actual angle of attack ⁇ 2 produced by the inclined-shaft inflow at the endplate 124 .
  • the cylindrical tangential inflow velocity ⁇ R1 and the second inflow component V1 sin ⁇ together form a second cylindrical endplate angle of attack ⁇ 22 produced by the inclined-shaft inflow at the cylindrical endplate 220 , in which the second cylindrical endplate angle of attack ⁇ 22 is negative.
  • the first cylindrical endplate angle of attack ⁇ 11 and the second cylindrical endplate angle of attack ⁇ 22 have the same absolute values but they are positive and negative respectively. Since in the diffuser-type endplate propeller 100 of the invention, the angle of attack ⁇ of the endplate 124 of the blade 120 is ⁇ 1° by design, so that when the blade 120 turns to the 0° circumferential position, the first actual angle of attack ⁇ 1 of the endplate 124 is less than the first cylindrical endplate angle of attack all by 1°, and the decreased actual angle of attack of the endplate 124 reduces the sheet cavitation phenomenon produced at the low-pressure side-surface.
  • endplate 124 c contacts the high-pressure side-surface of the propeller and the immerged depth of the endplate 124 at the 180° circumferential position is deeper, therefore, no cavitation phenomenon occurs which thus effectively improves the efficiency of the endplate propeller and suppresses the vibration and noise induced by the propeller.
  • the diffuser-type endplate propeller of the invention can prevent the flow at the high-pressure side-surface from back-flowing to the low-pressure side-surface.
  • the diffuser-type endplate propeller of the invention can largely reduce the serious extent of cavitation on the outer side of the endplate, even can eliminate cavitation on the endplate.
  • the invention can significantly improves the efficiency of the propeller and largely reduce the vibration and noise produced by the propeller.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
US14/151,827 2013-06-07 2014-01-10 Diffuser-type endplate propeller Abandoned US20140363298A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US15/860,685 US10155575B2 (en) 2013-06-07 2018-01-03 Diffuser-type endplate propeller

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
TW102120356 2013-06-07
TW102120356A TWI515147B (zh) 2013-06-07 2013-06-07 擴散型端板螺槳

Related Child Applications (1)

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US15/860,685 Continuation-In-Part US10155575B2 (en) 2013-06-07 2018-01-03 Diffuser-type endplate propeller

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3508415A1 (en) * 2018-01-03 2019-07-10 National Taiwan Ocean University Diffuser-type endplate propeller
US11945562B1 (en) * 2023-09-20 2024-04-02 Cyclazoom, LLC Shovel blade airplane/boat propeller

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US1117103A (en) * 1914-04-29 1914-11-10 William Steinbach Propeller.
US1597175A (en) * 1925-03-17 1926-08-24 Boening Ernest Propeller
US2099229A (en) * 1936-01-15 1937-11-16 Possenheim Louis Fin equipped rudder
DE1781084A1 (de) * 1968-08-21 1971-02-25 Richard Buchwald Vorrichtung zur Nutzbarmachung der Spitzenwirbel bei Schiffspropellern und Luftschrauben,Steigerung des Propulsionswirkungsgrades und Gewaesserbelueftung
US4300889A (en) * 1980-04-01 1981-11-17 Wormser Robert S Shallow draft propeller pocket
US4443202A (en) * 1981-05-29 1984-04-17 Arena Daniel J Surface propeller mounting assembly for boats
US4632636A (en) * 1983-05-27 1986-12-30 Edward H. Smith Propeller with blades having regressive pitch
US5205765A (en) * 1990-11-27 1993-04-27 The Pinnacle Corporation Boat hull and propulsion system or the like
US20090226323A1 (en) * 2005-11-01 2009-09-10 Masahiko Suzuki Quiet propeller
WO2012053378A1 (ja) * 2010-10-19 2012-04-26 三菱重工業株式会社 推進装置とそれを使用する船舶

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JPS58194689A (ja) * 1982-05-08 1983-11-12 Mitsui Eng & Shipbuild Co Ltd 船舶用プロペラの製造方法
DK71892D0 (da) * 1992-05-29 1992-05-29 Gori 1902 As Propel med optimal nyttevirkning ved frem- og baksejlads
CN2389840Y (zh) * 1999-06-11 2000-08-02 陈培歪 螺旋桨
JP5161423B2 (ja) * 2005-11-01 2013-03-13 株式会社ベルシオン 流体集束プロペラ
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KR20120132082A (ko) * 2011-05-27 2012-12-05 한국해양연구원 프로펠러 날개 끝에 곡판이 부착된 덕트 프로펠러 추진장치
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* Cited by examiner, † Cited by third party
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US698582A (en) * 1901-12-13 1902-04-29 Edward E Strothman Propeller-wheel.
US1117103A (en) * 1914-04-29 1914-11-10 William Steinbach Propeller.
US1597175A (en) * 1925-03-17 1926-08-24 Boening Ernest Propeller
US2099229A (en) * 1936-01-15 1937-11-16 Possenheim Louis Fin equipped rudder
DE1781084A1 (de) * 1968-08-21 1971-02-25 Richard Buchwald Vorrichtung zur Nutzbarmachung der Spitzenwirbel bei Schiffspropellern und Luftschrauben,Steigerung des Propulsionswirkungsgrades und Gewaesserbelueftung
US4300889A (en) * 1980-04-01 1981-11-17 Wormser Robert S Shallow draft propeller pocket
US4443202A (en) * 1981-05-29 1984-04-17 Arena Daniel J Surface propeller mounting assembly for boats
US4632636A (en) * 1983-05-27 1986-12-30 Edward H. Smith Propeller with blades having regressive pitch
US5205765A (en) * 1990-11-27 1993-04-27 The Pinnacle Corporation Boat hull and propulsion system or the like
US20090226323A1 (en) * 2005-11-01 2009-09-10 Masahiko Suzuki Quiet propeller
WO2012053378A1 (ja) * 2010-10-19 2012-04-26 三菱重工業株式会社 推進装置とそれを使用する船舶
US9021970B2 (en) * 2010-10-19 2015-05-05 Mitsubishi Heavy Industries, Ltd. Propulsion device and ship using the same

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3508415A1 (en) * 2018-01-03 2019-07-10 National Taiwan Ocean University Diffuser-type endplate propeller
US11945562B1 (en) * 2023-09-20 2024-04-02 Cyclazoom, LLC Shovel blade airplane/boat propeller

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Publication number Publication date
CN104229109A (zh) 2014-12-24
TW201446590A (zh) 2014-12-16
TWI515147B (zh) 2016-01-01

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Owner name: NATIONAL TAIWAN OCEAN UNIVERSITY, TAIWAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KEHR, YOUNG-ZEHR;REEL/FRAME:031956/0873

Effective date: 20131211

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION