Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H11/00—Marine propulsion by water jets
  • B63H11/02—Marine propulsion by water jets the propulsive medium being ambient water
  • B63H11/10—Marine propulsion by water jets the propulsive medium being ambient water having means for deflecting jet or influencing cross-section thereof
  • B63H11/107—Direction control of propulsive fluid
  • B63H11/117—Pivoted vane
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H11/00—Marine propulsion by water jets
  • B63H11/02—Marine propulsion by water jets the propulsive medium being ambient water
  • B63H11/10—Marine propulsion by water jets the propulsive medium being ambient water having means for deflecting jet or influencing cross-section thereof
  • B63H11/107—Direction control of propulsive fluid
  • B63H11/11—Direction control of propulsive fluid with bucket or clamshell-type reversing means

Definitions

• This invention relates to a new type of waterjet propuls ⁇ ive system for high speed boats.
• Today's systems consist of propellers (fixed or vari ⁇ able), surface piercing propellers, waterjets and air- propellers.
• Normal propellers in particular variable pitch propel ⁇ lers give good propulsive efficiency for speeds up to appr. 40 knots. Normally they are not used above 40 knots.
• Waterjets are more reliable than propellers and surface piercing propellers, and do not have any vibration prob ⁇ lems. Waterjets have a lower propulsive efficiency than a surface piercing propeller at high speed, but normally they have better propulsive efficiency and manoeuvring capabilities at low speed.
• the waterjet also make use of a paddle wheel, rotating in the same direction as the waterflow, but the paddle wheel is fitted into a closed pump house and acts like an impeller. This makes the sy ⁇ stem act like a waterjet, which is not the case in the above mentioned systems.
• the waterjet according to the invention it is pos ⁇ sible to achieve a propulsive efficiency similar to, or better than, a surface piercing propeller at high speed, and at the same time achieve similar or better reliabili ⁇ ty, manoeuvrability and propulsive efficiency as today's waterjets at low speed.
• Reversing can be done by using reverse ducts the same way as is done on ordinary waterjets.
• FIG.1 A non-limiting embodiment of an arrangement, specifically a waterjet for propulsion of high speed boats, according to the invention, is shown in Fig.1, 2 and 3.
• Fig.1 and Fig.2 show a side view, partly in section, of an embodiment of the present system, Fig.1 illustrating the system in reversing condition, whereas Fig.2 illu ⁇ strates the system at speed.
• Fig.3 shows the system as seen from above.
• a paddle wheel 1 is fitted into a substantially closed pump house 11, and is acting as an impeller.
• the pump house 11 is fitted with a water inlet 8 in the front and a water outlet 4 in the rear.
• the pump house 11 is formed in such a way that the lower part 2, between the inlet 8 and the outlet 4, is kept close to the paddle wheel 1 and forces the water to change direction and follow the lower part 2 of the house 11 until it is thrown out through the outlet 4.
• the upper part 3 of the pump house 11 can be constructed with an appropriate distance to the paddle wheel 1 , as its function is simply to close the pump house 11. Because the pump house is so to say fully closed, except from the inlet 8 and the outlet 4, a vacuum is created in the pump house 11, as the water is thrown out via the outlet 4. This vacuum sucks new water into the pump house 11, through the inlet 8, and then according to the dis- placement principle.
• an air inlet is arranged, preferably through the paddle wheel shaft 9 by making it hollow and with holes 10 from the hollow shaft into each chamber between the paddles 7. Air is then allowed to communicate with the system through an adjustable valve, for thereby controlling the vacuum level.
• the effect achieved by this is very similar to the effect achieved from a variable pitch propeller.
• the waterjet has no submer- ged parts creating friction.
• the only friction losses come from the lower part of the pump house and the water outlet.
• ordinary waterjets has to reduce velocity of the water entering the waterjet during high boat speed. This is done by a water intake formed like a diffusor, and leads to a large water in ⁇ take.
• the waterjet, according to the invention can take the water into the jet at the same velocity as the boat speed. This enables us to use a significant smaller water intake than ordinary waterjets.
• the waterjet can be made of the same materials as today's waterjets.
• Size, shape and number of paddles can to be adjusted to various engine and boat sizes, for example in the same way as it is done for ordinary waterjets and propellers.

Landscapes

• 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)
• Nozzles (AREA)
• Ship Loading And Unloading (AREA)
• Turbine Rotor Nozzle Sealing (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=19898304

Family Applications (1)

Country Status (5)

Families Citing this family (8)

Family Cites Families (2)

• 1995
  • 1995-06-15 NO NO952362A patent/NO952362L/no unknown
• 1996
  • 1996-05-31 CN CN96194713A patent/CN1060730C/zh not_active Expired - Fee Related
  • 1996-05-31 WO PCT/NO1996/000133 patent/WO1997000198A1/en not_active Application Discontinuation
  • 1996-05-31 EP EP96921165A patent/EP0832034A1/de not_active Withdrawn
  • 1996-07-10 AU AU62454/96A patent/AU6245496A/en not_active Abandoned

Non-Patent Citations (1)

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