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US3385374A - Marine propeller - Google Patents

Marine propeller Download PDF

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Publication number
US3385374A
US3385374A US616999A US61699967A US3385374A US 3385374 A US3385374 A US 3385374A US 616999 A US616999 A US 616999A US 61699967 A US61699967 A US 61699967A US 3385374 A US3385374 A US 3385374A
Authority
US
United States
Prior art keywords
jet
propeller
blade
blades
thrust
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.)
Expired - Lifetime
Application number
US616999A
Other languages
English (en)
Inventor
Kaplan Paul
August F Lehman
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.)
OCEANICS Inc
Original Assignee
OCEANICS Inc
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 OCEANICS Inc filed Critical OCEANICS Inc
Priority to US616999A priority Critical patent/US3385374A/en
Priority to GB2484/68A priority patent/GB1218363A/en
Priority to DE19681556511 priority patent/DE1556511B2/de
Priority to BE709657D priority patent/BE709657A/xx
Priority to NL6800936A priority patent/NL6800936A/xx
Priority to SE00835/68A priority patent/SE350231B/xx
Priority to ES349613A priority patent/ES349613A1/es
Priority to FR1553261D priority patent/FR1553261A/fr
Priority to NO00259/68A priority patent/NO127389B/no
Priority to CH100468A priority patent/CH491780A/de
Application granted granted Critical
Publication of US3385374A publication Critical patent/US3385374A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • B63H1/28—Other means for improving propeller efficiency
    • 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
    • B63H1/18—Propellers with means for diminishing cavitation, e.g. supercavitation
    • 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
    • B63H1/20—Hubs; Blade connections
    • 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
    • B63H1/28—Other means for improving propeller efficiency
    • B63H2001/286—Injection of gas into fluid flow to propellers, or around propeller blades
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H23/00—Transmitting power from propulsion power plant to propulsive elements
    • B63H23/32—Other parts
    • B63H23/34—Propeller shafts; Paddle-wheel shafts; Attachment of propellers on shafts
    • B63H2023/346—Propeller shafts; Paddle-wheel shafts; Attachment of propellers on shafts comprising hollow shaft members

Definitions

  • ABSTRACT OF THE DISCLOSURE A marine screw propeller having internal ducting connected to a huid-pressure source by means of which lluid is discharged as a jet sheet at a predetermined velocity and angle from critical locations on the blade surface in the area of the trailing edge.
  • the parameters of the blade and jet are so arranged that a condition of super-circulation is induced resulting in a lift force which exceeds the theoretical maximum obtainable due to camber and angle of attack.
  • Still another object of the invention is to provide a marine screw propeller design which can be made structurally strong without making it susceptible to cavitation and decreased eiciency.
  • increased thrust and eiciency are obtained from marine screw propellers through the control of the pressure distribution on the blades by inducing a condition of super-circulation, which is defined as a means of developing a lift force which exceeds the theoretical maximum attainable with any given propeller blade geometry by virtue of changes in camber and angle of attack.
  • a condition of super-circulation which is defined as a means of developing a lift force which exceeds the theoretical maximum attainable with any given propeller blade geometry by virtue of changes in camber and angle of attack.
  • the propeller is driven by a combination of torque applied to the propeller shaft and by the torque developed by the jet momentum reaction which occurs as a result of the discharge of jets from the trailing edges of the blades.
  • Propellers driven by drive shaft torque 'or jet momentum reaction generated by fluid discharge from the blades, as well as a combination of the two, are known in the art. In all cases, however, the total lift force which can be generated by the blades is limited by the phenomena of cavitation and/or separation of the liquid operating medium from the surfaces ot' the blades.
  • the present invention utilizes a jet discharge in the form of a jet ap in the vicinity of the trailing edges of the blades which is critically shaped in width, length, angle of discharge, and veice locity, to induce super-circulation, in addition to the benefit which results incidentally from the jet momentum recovery of the jet.
  • a jet discharge in the form of a jet ap in the vicinity of the trailing edges of the blades which is critically shaped in width, length, angle of discharge, and veice locity, to induce super-circulation, in addition to the benefit which results incidentally from the jet momentum recovery of the jet.
  • This is achieved with the jet ilap by modifying the chordwise pressure distribution of the foil so as to reduce the pressure peaks occurring with normal distributions while increasing the overall load developed by the pressure distribution profile.
  • FIGURE 1 is a view of one of the blades and a portion of the hub of a marine screw propeller in plan view, i.e., looking in the direction of the drive shaft of the propeller;
  • FIGURE 2A is a chord section view in enlarged scale of the blade, taken on the line 2 2 of FIGURE 1 looking in the direction of the arrows, showing the lift and thrust force vectors of both the foil eiiect and the jet-induced super-circulation effect, the latter vector including a relatively small jet momentum reaction component;
  • FIGURE 2B is a partial chord section similar to FIG- URE ZA but in larger scale to illustrate the jet slot width limits;
  • FIGURE 2C is a chord section view corresponding to FIGURE 2A showing the lift and thrust yforce vectors of a propeller in which there is a jet discharge aligned with the nose-tail line of the blade section so that super circulation does not occur although the jet momentum reaction torce remains;
  • FIGURE 3A is a diagrammatic view of a chord section of a blade or foil showing, superimposed thereon, a plot of the pressure distribution which occurs when the blade is driven at incidence without the present invention
  • FIGURE 3B is a view of the blade of FIGURE 3A, showing a plot of the upper surface pressure distribution utilizing a jet ilap deflection in accordance with the present invention
  • FIGURE 4 is a View in longitudinal section of the stern of a ship taken through the axis of the drive shaft and including a propeller and drive shaft assembly embodying the present invention
  • FIGURE 5 is a view in horizontal section through the stern of the ship of FIGURE 4, illustrating one representative mechanism for introducing fluid under pressure into the propeller blades;
  • FIGURE 6 is a plan or full-face view, looking the direction ofthe axis ofthe drive shaft of the propeller of FIG- URE 4 and having one of is four blades illustrating internal ducting by a section passing through all of the chord lines of the blade.
  • FIG. 1 the invention is illustrated as embodied in a marine screw propeller 10 (FIGURES 4 and 6) attached to a hollow tail or drive shaft section 11 in a ship 12 (illustrated only diagrammatically to show the underwater portion of the stern).
  • a marine screw propeller 10 (FIGURES 4 and 6) attached to a hollow tail or drive shaft section 11 in a ship 12 (illustrated only diagrammatically to show the underwater portion of the stern).
  • FIGURE 1 the propeller lil is illustrated in enlarged scale in FIGURE 1 and in still larger scale in FIGURES 2A and 2B.
  • each of the four blades, 10a' b, c and a' of the propeller 10 includes internal ducting of the type indicated generally by the numeral 13 in the blade section 19a.
  • the ducting 13 is preferably divided into discrete ducts 13a, b and c by means of contoured inner partitions 14a and b, terminating at the trailing edge 1S of the blade in an elongated discharge opening or series of openings 16, best seen in FIGURES 1 and 6, adapted to discharge a iluid jet sheet I (FIGURE 4) from the surface of the blade opposite the suction or low pressure side of the blade.
  • the inner hub openings and the iluid passageways are so designed so as to control the exit velocity of the uid at the trailing edge. It will be observed that the slot 16 extends over a substantial length of the trailing edge of the blade from a point near the central hub 17 to a point near the blad-e tip to approximately the 0.85 radius of the blade.
  • the drive shaft section 11 to which the propeller 10 is affixed is hollow and includes, in its portion disposed within the propeller, radial ports or openings I8 which place the interior conduit Ila of the shaft 11 in communication with the ducts 13a, b and c of each of the blades.
  • the jet velocity at any given point along lthe length of the jet ap discharge J should exceed the magnitude of the local water velocity at the particular point.
  • the sizes of the ports ⁇ 1'8 as lwell as the sizes of the ducts t13a, b and c can be selected and arranged to achieve this result.
  • the low path from the interior of the shaft l1 into each of the blades is further controlled by a tapered plug 18a.
  • the drive shaft il between the main propulsion motor (not shown) of the ship and the propeller, passes through a stationary collector box 19 having seals 19a and 1913.
  • the collector is connected by suitable conduits 20 and 21 to the output sides of pumps 22 and 23, the pumps having their input sides connected by conduits 24 and 25 to suitable openings in the ships hull beneath the water line, preferably at points having high pressures.
  • the hollow drive shaft section 11, within the collector box 19, is formed with radial openings 26 communicating with the hollow interior.
  • a contoured plug 27 can be included within the hollow shaft within the collector 19 to promote uniform flow.
  • torque is applied to the drive shaft in the conventional manner by means of the main propulsion engine and, in addition, uid is pumped through the ducts 113 and out of the slots 16 in a jet flap.
  • the pumps 22 and 23 are used to supply and to adjust 4the ow rate of the jets to the optimum value, recognizing that some pumping action will occur automatically, as the propeller rotates, due to the centrifugal force generated by the turning propeller.
  • the function of the jet flap emitted from the slots is so arranged in its shape, positioning and flow rate, in accordance with the present invention, that super-circulation is induced.
  • the concept of circulation is the basis of airfoil and propeller blade theory. Assuming a finite span foil, the lift per unit length of span varies directly with circulation. Lift is expressed as follows:
  • FIGURES 3A and 3B it will be seen that the pressure distribution on a foil due to super-circulation induced by the jet iiap (FIGURE 3B) differs considerably from that created by the foil at incidence (FIGURE 3A).
  • a total lift force from the pressure distribution is achieved without the pressure peak associated with the generation of the same total lift through foil incidence.
  • the limit of the maximum thrust obtained with incidence, camber, or both, is exceeded significantly by -the jet flap induced super-circulation effect.
  • the reduction in the maximum pressure peak magnitude for the case of the jet flap pressure pattern acts to inhibit the possibility of separation as well as the susceptibility to cavitation.
  • the jet ilap is discharged at an angle 1- to the nose tail line of the blade 10a.
  • the angle 1- is illustrated as being approximately 30 degrees, although as described below it can vary over a range of angles.
  • the latter component less the drag loss constitutes a net thrust gain of relatively small magnitude and is insignificant for practical and achievable ilow rates that would yield etiicient operation.
  • U.S. Patent No. 2,511,156 discloses a marine screw propeller in which this reaction component is utilized to augment the thrust of the propeller.
  • the lift force to which the present invention is directed is that indicated by the vector bearing the legend Additional Lift Due to Super-Circulation. To achieve supercirculation:
  • the thickness of the jet sheet i.e. the slot width
  • the jet stream angle must be between approximately 15 and 75 degrecs from the nose tail line of the blade prole at each particular radial section of the propeller as shown in FIGURE 2A
  • the velocity of the jet stream must be greater than the resultant water velocity at each parti-cular radial section of the propeller
  • the majority of the jet stream must be emitted between the blade root and approximately the 0.85 radial section as shown in FIGURE 1, with the jet slot being located in the region of the trailing edge of the blade or inward up to a distance of 0.15 chord as also shown in FIGURE 2A.
  • the parameters can be optimized to achieve a loading per unit area of the blade which can be increased tive to ten times over conventional average design loadings (loadings obtainable without the jet ap action) without increasing cavitation susceptibility.
  • the driving torque of the propeller is supplied by the main drive shaft and the increase in thrust loading is achieved without a corresponding increase in shaft torque.
  • the eiciency of the propeller is increased for any given required amount of total thrust.
  • the means for supplying fluid to the ducts within the blade can be widely varied, as can the geometry of the blades and the internal ducting.
  • the jet fluid used in the embodiment of the invention described herein is water, other liquids can be used as can gasses such as steam, air, machinery exhaust gas and the like. The invention should not, therefore, be regarded as limited except as defined by the following claims.
  • a marine screw propeller comprising a hub portion and a plurality of blades extending radially therefrom, each having a curvilinear foil surface, fluid duct means in the blades, and uid discharge openings disposed adja- -cent the trailing edges of the blades and disposed primarily in the space between the blade root and the'0.85 radial section of the blade to discharge fluid from said duct means in a shaped jet stream, said iluid duct means having inlet means communicating with said hub portion, said openings being shaped and arranged to direct the jet stream at an angle of between approximately 15 and 75 degrees to the nose-tail line of each radial profile of the blades and in a direction having a component opposite to the direction of thrust of the blades, and means to pass iluid through said duct means from the openings at a velocity greater than the resultant water velocity at each radial section of the blade, and having a predetermined magnitude to achieve predetermined local loading thereon and to establish super-circulation about the blades.
  • said duct means in each blade comprising a plurality of generally coplanar ducts separated by internal partitions, and ports in the hub communicating with the ducts, with the said duct and port dimensions and contours controlling the uid discharge velocity along the length of shaped jet discharge.

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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)
  • Insulation, Fastening Of Motor, Generator Windings (AREA)
US616999A 1967-01-23 1967-01-23 Marine propeller Expired - Lifetime US3385374A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
US616999A US3385374A (en) 1967-01-23 1967-01-23 Marine propeller
GB2484/68A GB1218363A (en) 1967-01-23 1968-01-17 A marine propulsion system
BE709657D BE709657A (de) 1967-01-23 1968-01-19
DE19681556511 DE1556511B2 (de) 1967-01-23 1968-01-19 Schiffsschraube
NL6800936A NL6800936A (de) 1967-01-23 1968-01-22
SE00835/68A SE350231B (de) 1967-01-23 1968-01-22
ES349613A ES349613A1 (es) 1967-01-23 1968-01-22 Una disposicion para propulsion marina.
FR1553261D FR1553261A (de) 1967-01-23 1968-01-22
NO00259/68A NO127389B (de) 1967-01-23 1968-01-22
CH100468A CH491780A (de) 1967-01-23 1968-01-23 Schiffsantrieb und Verfahren zu dessen Betrieb

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US616999A US3385374A (en) 1967-01-23 1967-01-23 Marine propeller

Publications (1)

Publication Number Publication Date
US3385374A true US3385374A (en) 1968-05-28

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ID=24471877

Family Applications (1)

Application Number Title Priority Date Filing Date
US616999A Expired - Lifetime US3385374A (en) 1967-01-23 1967-01-23 Marine propeller

Country Status (10)

Country Link
US (1) US3385374A (de)
BE (1) BE709657A (de)
CH (1) CH491780A (de)
DE (1) DE1556511B2 (de)
ES (1) ES349613A1 (de)
FR (1) FR1553261A (de)
GB (1) GB1218363A (de)
NL (1) NL6800936A (de)
NO (1) NO127389B (de)
SE (1) SE350231B (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4050849A (en) * 1976-04-19 1977-09-27 Sheets Herman E Hydrodynamic transmission for ship propulsion
US5464321A (en) * 1978-11-24 1995-11-07 The United States Of America As Represented By The Secretary Of The Navy Marine propeller
US10315742B2 (en) 2017-08-22 2019-06-11 Aurora Flight Sciences Corporation High efficiency, low RPM, underwater propeller
US11644046B2 (en) 2018-01-05 2023-05-09 Aurora Flight Sciences Corporation Composite fan blades with integral attachment mechanism
WO2024127049A1 (en) * 2022-12-15 2024-06-20 Kovacs Attila Propeller for a watercraft and watercraft having such a propeller

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2251468B3 (de) * 1972-10-20 2008-02-28 Licentia Patent-Verwaltungs-Gmbh Verfahren und Einrichtung zur Verbesserung des Wirkungsgrades von Antrieben für Wasserfahrzeuge
GB2164306B (en) * 1984-09-17 1988-08-24 Vickers Plc Multi-bladed propeller and shaft assembly
DE19734770A1 (de) * 1997-08-11 1999-02-18 Tina Artinger Einrichtung zur Verringerung der Randwirbel von endlichen dynamischen Auftriebskörpern durch Erzeugung einer Gegenströmung
BG64380B1 (bg) * 1999-04-26 2004-12-30 Добромир АЛЕКСАНДРОВ Витло
DE10160000B4 (de) * 2001-12-07 2005-10-27 Kvaerner Warnow Werft Gmbh Verfahren und Vorrichtung zum Reduzieren von Materialschäden an Schiffsrudern

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US736952A (en) * 1903-01-08 1903-08-25 William Logan Screw-propeller.
US1119178A (en) * 1912-07-15 1914-12-01 Carl A Krantz Propeller and driving means therefor.
US1190755A (en) * 1914-07-16 1916-07-11 John Hahn Method of propulsion for vessels and screw-propeller for effecting the same.
US2169325A (en) * 1934-06-08 1939-08-15 Julius J Novak Sustaining and propelling member for fluid-sustained craft
CA505082A (en) * 1954-08-17 Hauser Arnold Fluid propeller drive
GB774396A (en) * 1954-04-23 1957-05-08 Elfyn John Richards Improvements in or relating to helicopter rotor propulsion means
US3109495A (en) * 1962-12-18 1963-11-05 Thomas G Laug Base ventilated hydrofoil
US3209714A (en) * 1963-10-14 1965-10-05 Romald E Bowles Fluid control systems for foils

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR493771A (fr) * 1916-12-30 1919-08-21 Pierre Jean Baptiste Boiffin Système de propulsion dans les fluides par des jets de gaz, à haute température, animés d'un mouvement rotatoire autour d'un axe commun horizontal
FR22339E (fr) * 1917-08-04 1921-06-30 Pierre Jean Baptiste Boiffin Système de propulsion dans les fluides par des jets de gaz à haute température animés d'un mouvement rotatoire autour d'un axe commun horizontal
FR26777E (fr) * 1921-11-04 1924-03-15 Système de propulsion dans les fluides par des jets de gaz à haute température, animés d'un mouvement rotatoire autour d'un axe commun horizontal
US2058361A (en) * 1935-06-04 1936-10-20 Starr K Sherwood Propeller
US2511156A (en) * 1946-08-07 1950-06-13 Richard J Glass Propeller
DE805732C (de) * 1949-06-30 1951-05-28 Hermann Piontek Fluegelschraube bzw. Schaufelrad mit Duesenantrieb
DE846361C (de) * 1949-09-13 1952-08-11 Arnold Hauser Antriebseinrichtung mit einem mindestens zweifluegeligen Propeller, insbesondere fuer Schiffe
DE828651C (de) * 1950-06-27 1952-01-21 Rudolf Voigt Dipl Ing Schraubenpropeller mit Reaktionsantrieb
DE851001C (de) * 1951-03-08 1952-09-29 Hermann Piontek Fluegelschraube bzw. Schaufelrad mit Duesenantrieb, insbesondere fuer Schiffsantrieb

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA505082A (en) * 1954-08-17 Hauser Arnold Fluid propeller drive
US736952A (en) * 1903-01-08 1903-08-25 William Logan Screw-propeller.
US1119178A (en) * 1912-07-15 1914-12-01 Carl A Krantz Propeller and driving means therefor.
US1190755A (en) * 1914-07-16 1916-07-11 John Hahn Method of propulsion for vessels and screw-propeller for effecting the same.
US2169325A (en) * 1934-06-08 1939-08-15 Julius J Novak Sustaining and propelling member for fluid-sustained craft
GB774396A (en) * 1954-04-23 1957-05-08 Elfyn John Richards Improvements in or relating to helicopter rotor propulsion means
US3109495A (en) * 1962-12-18 1963-11-05 Thomas G Laug Base ventilated hydrofoil
US3209714A (en) * 1963-10-14 1965-10-05 Romald E Bowles Fluid control systems for foils

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4050849A (en) * 1976-04-19 1977-09-27 Sheets Herman E Hydrodynamic transmission for ship propulsion
US5464321A (en) * 1978-11-24 1995-11-07 The United States Of America As Represented By The Secretary Of The Navy Marine propeller
US10315742B2 (en) 2017-08-22 2019-06-11 Aurora Flight Sciences Corporation High efficiency, low RPM, underwater propeller
US11644046B2 (en) 2018-01-05 2023-05-09 Aurora Flight Sciences Corporation Composite fan blades with integral attachment mechanism
WO2024127049A1 (en) * 2022-12-15 2024-06-20 Kovacs Attila Propeller for a watercraft and watercraft having such a propeller

Also Published As

Publication number Publication date
DE1556511A1 (de) 1970-09-24
GB1218363A (en) 1971-01-06
BE709657A (de) 1968-07-19
ES349613A1 (es) 1969-10-01
NL6800936A (de) 1968-07-24
CH491780A (de) 1970-06-15
SE350231B (de) 1972-10-23
NO127389B (de) 1973-06-18
FR1553261A (de) 1969-01-10
DE1556511B2 (de) 1970-09-24

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