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
  • B63H11/11—Direction control of propulsive fluid with bucket or clamshell-type reversing means
• • 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

Definitions

• the invention relates to a method for operating a water jet drive for watercraft according to the preamble of patent claim 1 and an arrangement for carrying out the method according to the preamble of patent claim 9.
• propulsion devices for water vehicles using propulsion means that is to say both visual propellers of different geometries and so-called water jet propulsion systems, as is known, cannot be adapted to larger speed ranges without there being any adverse effects on the efficiency.
• Variable pitch propellers also have only a limited working range, whereby the best efficiency can be achieved over the entire prope 11 distance 1 only with a propeller blade position and a propeller speed / degree of progress ratio.
• a water jet drive Compared to a ship's propeller, which has to process an inflow speed that changes with the speed of the watercraft, but cannot otherwise be influenced, a water jet drive has the advantage that for the pump accelerating the water, an optimal inflow of the pump blade profiles in all driving ranges and all pump speeds and thus Operating points of the best efficiency can be achieved if the flow-determining nozzle of the water jet drive is designed so that its effective exit cross-section can be changed during operation.
• nozzle outlet speed of the water jet is optimal with regard to the nozzle efficiency, a flow velocity of the pump that changes with the speed of the watercraft, and a throughput that changes as a function of the speed of the water; see. GB-PS 1 063 945.
• control flaps of a water jet drive to be pivoted in opposite directions about each of a vertical axis, which are connected downstream of the jet outlet opening of a radial pump, the nozzle cross section being controlled by the control flaps according to the equation
• A nozzle cross section (in square inches)
• control flaps designed as cylinder jacket sections to the outlet end of the water jet drive and which are held by sector-shaped cheeks and which each have a horizontal axis about a vertical axis in a housing which is pivotally mounted on the pump housing by means of crossbeams to be pivoted in opposite directions; see. DE-OS 25 44 743.
• All of these controls have the characteristic that either beam deflection is only possible in a vertical direction with a simultaneous reduction of the nozzle exit area, which cannot be influenced separately, or a vertical jet deflection upwards and downwards is possible without changing the nozzle cross-section.
• the invention is based on the object of specifying a method and an arrangement for carrying out the method for a manual or automatic control of the nozzle outlet cross-section, regardless of the driving speed and as a result of the different pressures present at the nozzle outlet cross-section, which operate the water accelerating pump guaranteed in the range of optimal efficiencies in the entire operating range and by a controlled vertical deflection of the propulsion jet also allows the watercraft to be trimmed, which also enables extensive thrust reversal for reverse travel and for the braking process, and that the arrangement can also be carried out in towing mode, i.e. in the event of a breakdown Drive device - drive motor and / or pump - should still generate a usable control pressure.
• the method according to the invention achieves optimum operation with regard to thrust and efficiency of the water jet drive in all operating ranges with regard to speeds and driving speeds, since the associated effective cross section "Fw” is used independently of the driving speed “w” depending on the pump speed "n” via the variable effective nozzle cross section Water flow "Q” is regulated.
• a control rate, the throughput "Q" proportional speed "vx” or the associated dynamic pressure “pdynx” at a suitable location "x" within the flow channel are advantageously used as control criteria for the nozzle outlet cross section "F" to be controlled and
• the values "pdynx" and "n” or vx can either be supplied as a control signal to a computer and associated automatic control device or can be displayed in a suitable form for manual adjustment of the optimum.
• the invention likewise allows the vertical component of the effective water jet and thus the trimming to be carried out automatically, the deviation from the setpoint value of the inclination of the watercraft about the transverse axis in the case of a water jet drive and / or also about the longitudinal axis for the actuation of the flaps required for this when using two or more water jet drives on the watercraft, detected by suitable sensors and fed to the control in a suitable signal form.
• the nozzle according to the invention has an easily manageable, at least partially rectangular, cross-section and, in addition to an effective change in the nozzle cross-sections by changing the position of the two control flaps relative to one another, also permits a change in the vertical component of the effective component that is possible by simultaneously adjusting the two flaps to carry out the method Thrust. Furthermore, the possible lowering of the front mounting of the lower flap enables an almost complete reversal of thrust.
• a bypass opening is created within the nozzle by the possible lowering of the front end of the lower flap according to the invention, so that due to the injector effect which arises in this way, an enlargement of the accelerated water mass with a lower exit speed arises from the nozzle, particularly at low water depth in ports or on rivers the agitation of the bottom is reduced and is advantageously used in the area of low speeds to improve the beam efficiency and the thrust.
• the water-bearing bypass generated in this way can also be used as a passive rudder in towing and can generate useful control forces.
• the component carrying the nozzle is designed as a housing and is mounted so as to be pivotable about a vertical axis, which axis can be inclined relative to the vertical, cornering can be carried out easily and safely. All parts of the control, which generate the cross-sectional change of the nozzle, the vertical viewing deflection and the thrust reverser for reversing, are directly or indirectly connected to the housing, which leads to a simple, reliable and efficient design of the water jet drive .
• the upper flap can have an oppositely curved surface at the lower end, which serves as the upper limit of the nozzle cross section. This is very advantageous because by simultaneously closing the flow cross-section on the front edge of the lower control flap in the area of the bearings and on the rear edge between the facing surfaces of the lower and upper flap, the water channel of the entire water jet drive can be closed from the outlet side, so that a throughflow and / or damage to the inner pump parts when the drive is at a standstill while in port is safely avoided.
• Figure 1 shows a pump map with lines constant
• FIG. 2 shows a parallel projection of a control unit for the nozzle of a water jet reaction drive according to the invention
• FIG. 3 shows a section through the schematic nozzle according to FIG. 2 with the associated control flaps in the "closed position for downtimes",
• FIG. 4 shows a section through the schematic nozzle according to FIG. 2 with the associated control flaps in the position "slow travel with horizontal deflection downwards to reduce the onset",
• FIG. 5 shows a section through the schematically illustrated nozzle according to FIG. 2 with the associated control flaps in the position "slow travel with water quantity increased due to injector action at lower speed” and also the position of the control flaps as "passive rudder",
• 7 shows a section through the schematically represented nozzle according to FIG. 2 with the associated control flaps in the position "fast travel with reduced nozzle area and horizontal deflection downwards (negative" Aufki moment ")
• FIG. 8 shows a section through the schematically illustrated nozzle according to FIG. 2 with the associated control flaps in the "reverse travel and braking" position.
• FIG. 9 shows a further control nozzle, shown schematically in parallel projection, with two flaps that can be adjusted at both ends in a nozzle body that can be pivoted about the vertical axis, in the position for "slow travel with negative trim torque".
• FIG. 10 shows a nozzle according to FIG. 9 in the "brake and reverse travel" position.
• FIG. 11 shows a nozzle according to FIG. 9 in the position "slow travel with an increased amount of water at a lower speed due to the action of an injector"
• FIG. 12 shows a further control nozzle schematically shown in parallel projection with two flaps that can be adjusted at both ends in a nozzle body that can be pivoted about the horizontal axis in the position “travel at low speed in a right-hand curve”
• Figure 13 shows a nozzle according to Figure 12 in the position
• FIG. 15 shows a control scheme for water jet drives according to the invention.
• the dynamic pressure proportional to the throughput Q 1 can be chosen at any point of constant cross-section and constant flow direction within the pump or the flow channel.
• pdynx * means the dynamic pressure i measuring cross-section "Fx" at the operating point (10) optimum efficiency at the design speed "n *” (3) and the throughput "Q *", the pressure "pdynx” the measured value at the current pump speed "n”.
• FIG. 2 An exemplary embodiment for carrying out the method according to the invention will now be described with reference to FIG. 2, only the parts belonging to the invention being shown. From that in advance to one A flow channel arranged on the watercraft with an inlet having an intake opening at its front end, a pump downstream of the inlet in its central region for drawing in and accelerating water and a nozzle at the jet outlet opening at its rear end, therefore only the rear end of the pump body is shown.
• the pump body has an approximately circular cross section and merges downstream into a nozzle D formed by a nozzle body 19, an upper flap 20 and a lower flap 21.
• the nozzle body 19 is pivotally mounted on the pump body in the pivot axis 22, which is only partially shown, and can be adjusted vertically at an angle to the pump axis by means of the pivot device 37 (not shown in more detail).
• the end face 23 of the nozzle body 19 is designed in the shape of a circular arc.
• the underside of the nozzle body is open and closed by the lower flap 21.
• the middle bearing eyes 27 and 32 movably mounted flap 21 forms the lower boundary of the flow channel and the nozzle.
• the lower flap 21 also has lateral cheeks 24, which are used to guide the flap 21 in the nozzle body 19 and to limit the water jet when reversing.
• the upper flap 20 is rotatably mounted about a pivot axis 25 in the bearing eye 25 'of the nozzle body 19 and can be adjusted by an adjusting means 26 which acts on a bearing 31 and on the other hand a nozzle body 19 is pivotably mounted in a bearing eye 38. Furthermore, two adjusting devices 33 are provided between the bearing eyes 32 de lower flap and the bearing eye 31 of the upper flap 2.
• the lower flap 21 has bearings 27 at its front end, in which the swiveling device consisting of the indicated adjusting device 28, the angle levers 39 and the linkage 40 engages, with which the lower flap can be lowered at this end.
• Spacer tabs 29 are arranged on the bearing 27, the other ends of which are pivotably connected to the upper flap 20 in the bearings 30.
• the effective nozzle cross section is achieved by changing the gap 34 between the lower circular arc ⁇ shaped surface 35 of the upper flap 20 and the rear edge 36 of the lower flap 21 changeable.
• FIGS. 3 to 8 show the various possible positions of the control flaps 20 and 21 in relation to the nozzle body 19 serving as a flow channel and the flow directions of the propellant jet generated therewith, as well as the lowering of the flap 21.
• FIG. 5 shows the "bypass position" of the nozzle, the driving jet flowing in cross section 42 at the speed 43 of the bypass cross-section 44 corresponding to the driving speed 45 corresponding to the driving speed 45 by friction and mixing a lower exit velocity compared to the driving jet 46 in cross section 34 and thus improves the nozzle efficiency in the low vehicle speed range.
• FIGS. 9 to 11 show a second exemplary embodiment of such a control nozzle.
• the gap 34 between the rear edges 36a, 36b of the flaps 21a, 21b is closed, the front edge 47a or 47b or both is adjusted such that the gap accelerated by the pump accelerates the water in almost the same way Flow direction in the pump can flow in the opposite direction and thus creates a shot opposite to the normal direction of travel. If, on the other hand, the gap 34 is additionally opened, a bypass acting as an injector is created.
• FIGS. 12 to 14 show another version rotated by 90 ° of the control device shown in FIGS. 9 to 11, the horizontal beam deflection and thus the control of the travel direction and being shown here by the simultaneous pivoting of the two flaps 21a, 21 in the same direction by pivoting the nozzle body 1 about the horizontal axis 22, the vertical deflection of the driving jet for trimming is achieved.
• the trimming of the watercraft described above can of course be carried out automatically with the aid of a computer.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Ocean & Marine Engineering (AREA)
• Control Of Turbines (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

Priority Applications (1)

Applications Claiming Priority (4)

Publications (1)

Family

ID=25888404

Family Applications (1)

Country Status (3)

Families Citing this family (13)

Citations (3)

Family Cites Families (7)

• 1990
  • 1990-10-23 DE DE4033674A patent/DE4033674A1/de active Granted
  • 1990-12-12 WO PCT/DE1990/000959 patent/WO1991009773A1/de active IP Right Grant
  • 1990-12-12 DE DE91900165T patent/DE59005129D1/de not_active Expired - Fee Related
• 1991
  • 1991-07-25 EP EP91900165A patent/EP0460144B1/de not_active Expired - Lifetime

Patent Citations (3)

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