Wave-powered propulsion system
Patent Information
- Application Number
- EP2023783465
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-08-25
- Filing Date
- 2023-08-24
- Publication Date
- 2025-07-02
AI Technical Summary
Current wave energy systems for propelling boats face inefficiencies and high costs due to environmental challenges and are not designed for flexible operation, particularly during adverse conditions or maneuvers, making them uncompetitive with other renewable energy sources and posing safety risks.
A wave propulsion system with a shutter that can be submerged or raised, mounted at the rear of a boat, utilizing a base connected to a movable yoke and articulated assembly to harness wave energy for propulsion while allowing disengagement during unfavorable conditions, reducing interference with boat operations and maintaining maritime safety.
The system enhances propulsion efficiency, reduces fuel consumption, and enables the generation of electrical energy, while allowing for safe operation and maintenance by being easily disengaged, thus improving the cost-effectiveness and adaptability of wave energy conversion for boat propulsion.
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Figure 1.1
Abstract
Description
Description Title: Wave propulsion system Technical field
[0001] The present invention relates to the field of propulsion, and more particularly to a wave propulsion system using wave energy to propel a boat. Prior art
[0002] Waves, a wave-like phenomenon generated primarily by wind and forming on the surface of water in seas and oceans, are capable of providing so-called renewable energy. The energy generated by converting this renewable energy can be mechanical, hydraulic, or electrical. In the case of conversion to mechanical energy, the mechanical energy generated can be used to propel a boat, for example.
[0003] Capturing and converting this renewable energy can be achieved in a variety of ways, such as through a wave energy system. Most current wave energy systems are based on the same principle, which involves moving a mobile element relative to a fixed element in response to the movement of the waves. This movement of a first element relative to a second is then converted into usable energy.
[0004] The main current obstacles to the commercial development of wave energy systems, such as wave propulsion systems, are a lack of maturity and / or efficiency, and / or high manufacturing and maintenance costs. Indeed, the harsh environmental conditions to which they are subjected coupled with moderate efficiency make the cost of energy production (electrical or mechanical) uncompetitive compared to other energies, such as fossil fuels or other renewable energies such as solar or wind, whose technologies are now mature with a manufacturing cost that continues to decrease. In addition, a wave energy system designed to propel a boat and / or produce energy from a boat must generally be designed and integrated from the design stage of the boat, involving significant costs and constraints.Furthermore, existing wave energy systems are generally not designed to be disengaged when weather conditions are not conducive to its operation or during delicate maneuvers, such as towing the vessel, as defined in the SOLAS standard, or docking at a quay.
[0005] Therefore, there remains a dual need, a need to propose a solution with a high efficiency / cost ratio capable of efficiently converting renewable energy generated by wave motion for boat propulsion and / or electrical power generation, and a need to propose a solution that can be installed on many types of boats, and which, after installation, meets maritime safety requirements. Summary
[0006] This disclosure improves the situation.
[0007] There is provided a wave propulsion system configured to be installed on a boat, said system comprising a flap, said wave propulsion system being able to place the flap in a working configuration, where the flap is submerged in the water, or in a raised configuration, where the flap is out of the water, the wave propulsion system being able to comprise: a base mounted at the rear of the boat, the base being connected to a yoke movable relative to the base, the yoke being arranged so as to place the flap in the working configuration or the raised configuration, an articulated assembly connecting the flap to said yoke, the articulated assembly being arranged so as to allow oscillation of the flap under the action of the movements of the boat caused by the movements of the waves when said flap is in the working configuration, a lifting actuation means making it possible to switch from the working configuration to the raised configuration.
[0008] Advantageously, thanks to these provisions, the propulsion generated by the wave propulsion system, when the flap is placed in the working configuration, can lead to a reduction in the stress on the other means of propulsion of the boat (e.g. cargo ships or passenger ships). For example, when the boat is equipped with a propeller engine as the primary means of propulsion, the use of the wave propulsion system mounted at the stern of the boat can advantageously reduce fuel consumption. According to another additional advantage, the wave propulsion system, when it is additionally coupled to a generator (e.g. electric), via an energy conversion chain for example, can provide electrical energy to the boat.Furthermore, advantageously, when the flap is placed in the raised configuration, it is then possible to clear the space located at the rear of the boat (at the stern of the boat) to facilitate various operations, such as for example emergency or non-emergency towing of the vessel such as a LNG carrier, or to enable the wave propulsion system to be disengaged. when conditions are not optimal for its operation, such as the absence of swell or excessively strong swell, avoiding any risk of damaging the wave propulsion system or damaging the vessel, or even allowing safe docking.
[0009] In particular, advantageously, it is possible to clear the rear of the boat by putting the hinged assembly and the flap completely out of the water, and without reducing the surface area of the deck (eg main) at the rear of the boat.
[0010] Furthermore, advantageously, the size of the system is included (or even fully included) within the width of the boat. In particular, the dimensions and / or arrangements of the base, and / or the fork, and / or the articulated assembly, and / or the flap are configured to limit the size of the wave energy system, and in particular configured so that the size of the system is included (or even fully included) within the width of the boat. The vessel can dock, on the right or left side of the hull, eliminating or at least limiting the risks of interference between the system and the quay. The presence of the system does not prevent the mooring of the boat to the quay.
[0011] By flap, it can also be understood foil or hydrofoil.
[0012] By switching from the working configuration to the raised configuration, it can be understood that the shutter switches from the working configuration to the raised configuration, and vice versa.
[0013] By base mounted at the stern of the boat, it can be understood that the base is mounted on the rear external surface of the hull of the boat, arranged so as to be below the deck (e.g. the main deck) of the boat and above the water, so that the fork is permanently out of the water, and so that in the raised configuration, the hinged assembly and the flap are placed completely out of the water but without reducing the surface area of the deck located at the stern of the boat (or reducing the useful surface area of the deck at the stern of the boat or limiting the use of the useful surface area of the deck located at the stern of the boat). The base is therefore fixed on the stern, above the waterline when the vessel is unloaded, and preferably above the waterline of the vessel under maximum load, usually called the reference waterline.
[0014] Boat movement can be understood as pitching and / or heaving movements generated by the movement of the waves (i.e., by the swell). The pitching and / or heaving energy of the boat is converted into propulsion energy via the wave propulsion system to generate the oscillation of the flap.
[0015] To a lesser extent or in addition, the energy of the swell via the movement of the waves can also be transmitted directly to the propulsion flap, adding to the movements generated by the boat and thus reinforcing the oscillation of the flap.
[0016] In one or more embodiments, the yoke may be rotatably mounted on the base between a low position and a high position.
[0017] The high position of the yoke allows the shutter to be placed in the raised configuration, and the low position of the yoke allows the shutter to be placed in the working configuration.
[0018] In one or more embodiments, the boat may comprise a longitudinal direction X and in which the base comprises a first bearing and a second bearing, the first and second bearings being arranged on either side of a median plane (XM), the yoke being connected (A1; A1') to the first and second bearings by respective journals.
[0019] In one or more embodiments, the angle of rotation between the low position and the high position of the yoke around the axis of the journals (A1, A1') may be greater than 70 degrees, preferably greater than 105 degrees, and even more preferably greater than 120 degrees.
[0020] In one or more embodiments, the articulated assembly may comprise at least a first arm and a second arm connected to the yoke and to at least one flap arm by respective pivot links (A2, A2', A3, A3'), said first arm and said second arm being arranged to cross and pivot relative to each other in a plane perpendicular to the flap and along the longitudinal direction of the boat X, said flap arm being connected to the flap by at least one pivot link (A4) with the flap.
[0021] In one or more embodiments, the articulated assembly may comprise at least a first arm and a second arm connected to the yoke and to at least one flap arm (230a) by respective pivot links (A2, A2', A3, A3'), said first arm and said second arm being arranged to cross and pivot relative to each other in a plane perpendicular to the flap and along the longitudinal direction of the boat X, said flap arm being connected to the flap by at least one pivot link (A4) with the flap, the articulated assembly being configured so that the oscillation of the flap under the action of the boat results simultaneously from the work of the first arm and the second by pivoting relative to the yoke by the pivot links (A2', A3)' and relative to the flap arm by the pivot links (A2, A3), as well as from the work of the flap relative to the flap arm around the pivot link (A4) between the flap and said at least one flap arm.
[0022] In one or more embodiments, the articulated assembly may include first and second arms connected respectively to one or a plurality of flap arms and to the yoke, and which are arranged symmetrically with respect to the median plane (XM).
[0023] In one or more embodiments, the articulated assembly may comprise at least a first set of active and / or passive motion control elements and at least a second set of active and / or passive motion control elements configured to respectively control the pivoting of the first arm and the second arm, said first set of motion control elements being arranged between the yoke and the first arm, and said second set of motion control elements being arranged between the yoke and the second arm.
[0024] Thus, advantageously, the use of a set of passive and / or active motion control elements between the arms of the articulated assembly makes it possible to enhance the propulsion efficiency of the wave energy system, for example by causing a form of mechanical resonance to appear in the movement of the flap. This mechanical resonance in the movement of the flap may be dependent on the configuration of the sets of motion control elements and / or the configuration of each motion control element.
[0025] By active, it can be understood that the motion control elements of a set of active motion control elements can be controlled by a control unit so as to adapt the characteristics of the motion control elements to external conditions, such as for example in relation to the swell encountered, or to the different phases of movement of the propulsion flap and / or the first and second arms. This control requires an electrical and / or hydraulic power supply.
[0026] Thus, advantageously, when the sets of motion control elements are active, it is possible to adapt their characteristics. By their characteristics, it can be understood, for each motion control element, their respective stiffness, their respective inertia, and their respective damping. The respective damping of each active motion control element can be positive if the movement is slowed, or negative if energy is injected to increase the oscillation of the shutter.
[0027] In one or more embodiments, the first set of motion control elements and / or the second set of motion control elements may be passive, each set of motion control elements may respectively include a first return spring and a second return spring.
[0028] When the first set of motion control elements and / or the second set of motion control elements are passive, the mechanical resonance in the movement of the shutter may be dependent on the stiffness of the return springs.
[0029] In one or more embodiments, the first set of motion control elements and / or the second set of motion control elements are active, each set of motion control elements may respectively comprise a first actuator and a second actuator.
[0030] The first cylinder and the second cylinder can be linear cylinders.
[0031] In one or more embodiments, the first set of motion control elements and / or the second set of motion control elements are active, each set of motion control elements may respectively comprise a first screw-nut system and a second screw-nut system.
[0032] In one or more embodiments, the base may include a guide member for guiding a tow cable.
[0033] Preferably, the tow cable is used when the shutter is placed in the raised configuration.
[0034] In one or more embodiments, the guide element may be formed as a through opening, and when the shutter is placed in the raised configuration, a space is released and which is defined by an opening cone extending from said opening, said opening cone being defined by an opening angle of at least 180 degrees in a plane perpendicular to the median plane XM, and at least 30 degrees in the median plane XM, preferably at least 60 degrees in the median plane XM.
[0035] The guide element may be an orifice included in a fairlead meeting the constraints defined in the SOLAS standard for towing very large vessels such as LNG carriers. The fairlead may be defined by a minimum diameter of 600 millimeters and a minimum height of 300 millimeters.
[0036] In one or more embodiments, the lifting actuating means may be at least one hydraulic cylinder or at least one electric cylinder or at least one screw-nut system.
[0037] In one or more embodiments, the wave propulsion system may include at least one locking device for locking the flap in the working configuration or the raised configuration.
[0038] In one or more embodiments, the flap may have a rectangular or triangular or trapezoidal or ellipsoidal shape in the XY plane, and a symmetrical NACA profile type shape in the XM plane.
[0039] In one or more embodiments, the shutter arm may comprise at least one means for actively adjusting an angle between the shutter and the shutter arm along a plane perpendicular to the shutter and along the transverse direction of the shutter.
[0040] The present disclosure also relates to an assembly comprising a system according to the present disclosure and a boat, the system being mounted at the rear of the boat, preferably at the stern of the boat.
[0041] In one or more embodiments, the vessel may be a cargo vessel or a passenger vessel.
[0042] A cargo ship can be understood to mean a container ship (carrying processed goods), a bulk carrier (carrying ores, cereals, rubble, sand, etc.), or a chemical tanker, a gas tanker, an oil tanker, an LNG carrier, or a roll-on / roll-off ship.
[0043] In one or more embodiments, the base may be mounted on the rear outer surface of the boat hull at the stern, the base being positioned to be below the boat deck and above the water, such that the fork is permanently out of the water, and such that in the raised configuration, the hinged assembly and the flap are positioned completely out of the water without reducing the deck area of the boat.
[0044] In one or more embodiments, the footprint of the system is entirely included within the width of the boat. Brief description of the drawings
[0045] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analyzing the attached drawings, in which: Fig. 1
[0046] [Fig. 1] illustrates a wave propulsion system mounted on a vessel such as a cargo ship. Fig. 2a
[0047] [Fig. 2a] illustrates a perspective view of the propulsion system with a rotatably mounted yoke. Fig. 2b
[0048] [Fig. 2b] illustrates a top view (XY plane) of Figure 2a. Fig. 2C
[0049] [Fig. 2c] illustrates a sectional and perspective view of Figure 2a along the section plane A-A'. Fig. 3
[0050] [Fig. 3] illustrates a sectional view B-B' and side view of the wave propulsion system of Figure 2a placed in the raised configuration. Fig. 4
[0051] [Fig. 4] illustrates the kinematics of the propulsion flap under the action of the ship's pitching and waves in working configuration. Fig. 5
[0052] [Fig. 5] illustrates the wave propulsion system mounted in translation on a boat. Description of the embodiments
[0053] In the various figures, the same references designate identical or similar elements. For reasons of clarity of the presentation, certain elements may not be shown to scale.
[0054] Figure 1 shows a wave energy propulsion system mounted on a vessel such as a cargo ship.
[0055] The wave propulsion system 100 can be mounted at the rear of the boat, for example at the stern of the boat. In the example of FIG. 1, the wave propulsion system can be in the working configuration, i.e. corresponding to the partial or total immersion of the flap 105 in the water.
[0056] The vessel 103 may be a ship such as a cargo ship or a passenger ship and include a longitudinal direction X and a transverse direction Y. Cargo ships may be, for example, a container ship (comprising processed goods), a bulk carrier (comprising ores, grain, rubble, sand, etc.), or a chemical tanker, or an LNG or oil tanker.
[0057] Passenger ships can be, for example, ferries or cruise ships.
[0058] As described in Figure 1, when the wave propulsion system is in the working configuration, the propulsion flap may be partially or totally submerged, preferably totally submerged, so as to allow propulsion of the boat via the oscillation of the flap generated by the movements of the boat, themselves generated by the swell, thus limiting the use of its electric motor or its combustion engine for example. The movements of the boat generated by the swell may be pitching and / or heaving movements of the boat, the pitching and / or heaving energy being transmitted to the flap so as to cause its oscillation via the articulated assembly and therefore the propulsion of the boat.
[0059] Additionally, to a lesser extent, wave energy can also be directly transmitted to the shutter, thus enhancing its oscillation.
[0060] In one or more embodiments, the converted energy can also be used, partially or totally, to generate electrical energy via a conversion chain connected to a converter (e.g. electric generator, not shown), the conversion chain being connected to the wave propulsion system 100, for example connected to the articulated assembly.
[0061] The wave propulsion system may comprise a base 110 fixed to the rear of the boat, e.g. to the stern of the boat, and connected to a yoke 115, as well as an articulated assembly 120 making it possible to connect the yoke 115 to the propulsion flap 105.
[0062] In one or more embodiments, the base may be mounted on the rear external surface of the boat hull at the stern. The base may be arranged to be below the boat deck and above the water, such that the fork is permanently out of the water, and such that in the raised configuration, the hinged assembly and the flap are positioned completely out of the water but without reducing the deck area of the boat (or reducing the usable deck area at the rear of the boat).
[0063] In particular, in one or more embodiments, the base is therefore fixed on the stern, above the waterline when the vessel is unloaded, and preferably above the waterline of the vessel under maximum load, usually called the reference waterline.
[0064] The articulated assembly may be arranged to allow oscillation of the propulsion flap (or flap) under the action of the movements of the boat generated by the swell (i.e. by the movements of the waves), when the flap is placed in the working configuration and thus generate propulsion of the boat. The yoke may be arranged to place the propulsion flap in the working configuration or the raised configuration. More precisely, the movement of the yoke, between a low position and a high position of the yoke, allows the movement of the articulated assembly to be driven, which in turn drives the propulsion flap in order to place it from the working configuration to the raised configuration, and vice versa (from the high position to the low position).
[0065] For this purpose, the yoke can be mounted in rotation or translation on the base between the low position and the high position.
[0066] Furthermore, whether in the lowered or raised position, the fork (and the base) can be permanently out of the water. In particular, they can be permanently above the waterline of the boat.
[0067] Figures 2a to 2c illustrate the wave propulsion system arranged in the working configuration and comprising a rotatably mounted yoke.
[0068] More specifically, Figure 2a illustrates a perspective view of the wave propulsion system with a rotatably mounted yoke, Figure 2b illustrates a top view (XY plane) of Figure 2a, and Figure 2c illustrates a sectional and perspective view of Figure 2a along a section plane A-A'.
[0069] The base may comprise a first bearing 210a and a second 210b, the first and second bearings being arranged on either side of a median plane (XM), and the yoke may be connected A1; A1' to the first and second bearings by respective journals.
[0070] For example, the first bearing 210a and the second bearing 210b may be respectively defined in a first projection and a second projection located respectively at a first end and a second end of the base, the projections being arranged to be in opposition. The yoke (eg in the form of a U) may comprise a first and a second journal connected A1; A1 ' respectively to the first and second projection via the first and second plate.
[0071] Further, the base may include a guide member 210c configured to guide a towing cable when the flap is positioned in the raised and / or lowered configuration. For example, the guide member may be formed as a through opening. For example, the guide member 210c may be a through opening in a third projection included in the base 110 so as to form a fairlead. The through opening may have a diameter greater than 600 millimeters and the fairlead may have a height of at least 300 millimeters and have structural characteristics to meet the constraints defined in the SOLAS standard relating to emergency towing.
[0072] The shutter can be connected to the articulated assembly via a shutter arm 230a.
[0073] For example, the flap arm 230a may be connected to the yoke via at least a first arm 220a and a second arm 220b connected to the yoke 115 and to the flap arm 230a by respective pivot connections A2, A3, A2', A3'. The first arm and the second arm may be arranged to cross and pivot relative to each other in a plane perpendicular to the flap, for example a plane XM, and in the longitudinal direction of the boat Y.
[0074] With reference to Figure 2b, the shutter arm may further be connected to the shutter by at least one respective connection A4.
[0075] Thus, the oscillation of the flap under the action of the boat in the working position can result simultaneously from the work of the first arm and the second by pivoting relative to the yoke by the pivot connections A2', A3' and relative to the flap arm by the pivot connections A2, A3, as well as from the work of the flap relative to the flap arm around the pivot connection A4 between the flap 105 and said at least one flap arm 230a. In other words, the oscillation of the flap can be ensured by the simultaneous work of each of the pivots A2, A3, A2', A3', and A4.
[0076] In one or more preferred embodiments, the articulated assembly may comprise first and second arms connected respectively to one or a plurality of shutter arms and to the yoke, and which are arranged symmetrically with respect to the median plane (XM).
[0077] In addition, the first arms can be separated from each other so that the distance between them is less than the width of the boat (or ship). Similarly, the second arms can be separated from each other so that the distance between them is less than the width of the boat (or ship). This helps to reduce the footprint of the wave energy system so that it is fully included within the width of the boat.
[0078] For example, one or a plurality of shutter arms 230a, 230b may be connected to the yoke by at least two first arms 220a, 220c connected respectively to the yoke 115 and to the arm or to the plurality of shutter arms 230a, 230b by pivot connections A2, A2', and may be connected to the yoke by at least two second arms 220b, 220d connected respectively to the yoke and to the arm or to the plurality of shutter arms 230a, 230b by pivot connections A3, A3'.
[0079] The shutter may be connected to one or a plurality of shutter arms by respective pivot links A4, A4'.
[0080] In one or more embodiments, the first arms or the second arms, or the shutter arms may constitute a single respective part in the form of an inverted II or not. For example, the first arms 220a, 220c may be comprised in a part in the form of an inverted II.
[0081] Further, with reference to Figure 2c, the articulated assembly 120 may comprise at least a first set of motion control elements 240a, 240b and a second set 245a, 245b of motion control elements respectively configured to control (or drive) the pivoting of the first and second arms. The first set of motion control elements may be arranged between the yoke 115 and the first arm 220a, and the second set of motion control elements may be arranged between the yoke 115 and the second arm 220b.
[0082] Further, each set of motion control elements may be a set of active and / or passive motion control elements.
[0083] In one or more embodiments, when the first set of motion control elements and / or the second set of motion control elements are passive, each set of motion control elements respectively comprises a first return spring 240a, 245a and a second return spring 240b, 245b.
[0084] As an example (Figure 2c), the first set 240a, 240b of motion control elements may include a first return spring (e.g., compression or extension) 240a connected to the yoke 115 and the first arm 220a by respective pivot links, and a second return spring 240b (e.g., compression or extension) connected to the yoke 115 and the first arm 220a by respective pivot links. Similarly, the second set 245a, 245b of motion control elements may include a first return spring (e.g., compression or extension) 245a connected to the yoke 115 and the second arm 220b by respective pivot links, and a second return spring 245b (e.g., compression or extension) connected to the yoke 115 and the second arm 220b by respective pivot links.
[0085] In one or more embodiments, the first set of motion control elements and / or the second set of motion control elements are active, each set of motion control elements respectively comprising a first cylinder (eg linear cylinder) 240a, 245a and a second cylinder (eg linear cylinder) 240b, 245b.
[0086] Each cylinder of the motion control element sets can be connected to a respective motor driven by a control unit so as to adapt the characteristics (eg stiffness, damping, inertia) of each cylinder in relation to external conditions or in relation to the movement phases of each arm or in relation to the movement of the boat, and thus optimize the propulsion effort of the flap during propulsion. External conditions can be, for example, the type of swell encountered.
[0087] The control unit can be placed on the wave energy system or placed directly on the boat, for example.
[0088] Further, when the articulated assembly comprises first and second arms, the articulated assembly may comprise first and second sets of motion control elements arranged symmetrically with respect to the median plane XM.
[0089] In order to maintain the wave propulsion system in the working configuration or the raised configuration, it may comprise at least one locking device (not shown in Figures 2a to 2c) for locking the position of the flap in one or other of the configurations. For example, the locking device may be included between the yoke and the base.
[0090] In one or more embodiments, the locking device is mounted on the yoke so as to be integral with its movement.
[0091] According to one example, the locking device may be a rack and pinion system coupled to a key (or locking shaft / bar) locking a locking position 280a or 280b respectively locking the yoke in a low position so that the shutter is placed in a working configuration, and in a high position so that the shutter is placed in a raised configuration. For example, each locking position may be formed by two collinear openings, the first opening being arranged on the base and the second opening being arranged on the yoke. When the yoke moves from the low position to the high position, the two openings of the high position are aligned so as to allow the insertion of the key by the locking device.
[0092] When the flap is placed in the working configuration via the yoke placed in the low position, the locking device makes it possible to prevent rotation of the yoke and thus guarantees good transmission of the propulsion force and other hydrodynamic forces applied to the flap (and / or good propulsion efficiency) via the connection A1, A1' and the inserted key (not shown) in the locking position forming the low position.
[0093] In one or more embodiments, the wave propulsion system may include at least two locking devices and first and second locking positions arranged symmetrically on either side of the XM plane.
[0094] In one or more embodiments, the wave propulsion system may comprise at least three locking positions on a single side of the XM plane, or on either side of the XM plane. Such arrangements make it possible to place the wave propulsion system in one or more intermediate positions between the working configuration (i.e. low position of the yoke) and the raised configuration (i.e. high position of the yoke).
[0095] Referring to Figure 2b or Figure 3, the wave propulsion system may include a lifting actuation means or a plurality of lifting actuation means 260 configured to place the propulsion flap in the working configuration or the raised configuration.
[0096] The lifting actuating means may be arranged between the base and the yoke via respective pivot connections. For example, the lifting actuating means may be a hydraulic cylinder such as a double-acting linear cylinder or a screw-nut system.
[0097] In one or more embodiments, the plurality of lifting actuating means is a plurality of hydraulic cylinders (or a plurality of screw-nut systems) comprising at least two hydraulic cylinders (or at least two screw-nut systems). Preferably, the plurality of hydraulic cylinders (or a plurality of screw-nut systems) of the lifting actuating means 260 comprises at least four hydraulic cylinders (at least four screw-nut systems).
[0098] For example (Figure 2b or Figure 3), the cylinders of the plurality of hydraulic cylinders 260 can be connected to the base by a respective pivot connection A6, and the rod of each hydraulic cylinder for transmitting the force (e.g. by pushing) to cause the articulated assembly and the flap to move can be connected to the yoke by a respective connection A7, see Figure 3 or Figure 2b. When actuating the cylinders to move from the working configuration to the raised configuration (after unlocking the locking position by the locking device), or vice versa, the force transmitted by the rods of the cylinders to the yoke allows it to rotate around the base along the connections A1, A1' formed by the plates and the trunnions so that the yoke moves from the low position to the high position, carrying with it the articulated assembly and the propulsion flap (or flap), see Figure 3.
[0099] The flap may be presented as a thin structure extending mainly in two directions, a longitudinal x-direction and a transverse y-direction, with a thin thickness in the third direction (Z-direction). The thickness of the flap may vary between the leading edge and the trailing edge in the manner of an aerodynamic spoiler.
[0100] The flap can have a rectangular, triangular, trapezoidal, or ellipsoidal shape. For example, the shape of the flap can be similar to the tails of marine mammals, such as dolphins or whales. The flap can have dimensions where the length along the Y axis is greater than the width along the X axis. The thickness of the flap is defined so as to be consistent with the other quantities, particularly from the point of view of resistance to forward movement (this is to minimize drag).
[0101] The dimensions of the propulsion flap must be adapted to the dimensions of the wave propulsion system, which must itself be adapted to the environmental conditions and constraints of the vessel. For example, the dimensions of the flap can be in a range of 4 to 46 meters for lengths (length generally not exceeding the width of the vessel), 2 to 13 meters for widths, and for a maximum thickness (or height) of up to 200 centimeters. More precisely, the dimensions are 30 meters for the length located at the end of the flap, 8.75 meters for the width, and 130 centimeters for the maximum height (or thickness).
[0102] According to one embodiment, the flap can be made of steel or composite materials (such as fiberglass or carbon fiber plastic) or a combination of both. The composite material construction can allow the propulsion flap to be configured with a certain flexibility, in particular by controlling the arrangement of the fibers along the chord. This flexibility optimizes the propulsive aspect, like a flipper. In addition, the use of composite materials to make the flap also allows the system to be made lighter.
[0103] According to one embodiment, the flap may have an aircraft wing profile or a symmetrical NACA type profile.
[0104] Figure 3 shows a sectional view B-B' and side view of the wave propulsion system of Figure 2a placed in the raised configuration.
[0105] The flap 105 can be completely removed from the water via the lifting actuation means 260 allowing the rotation of the yoke (and therefore of the articulated assembly) around the pivot connection A1, A1' with the base allowing it to move from the low position to the high position.
[0106] In this raised configuration, the rear of the boat can be completely (or partially) freed up, allowing various operations to be carried out, such as towing (e.g. emergency towing) the vessel or docking at a quay. Indeed, the dimensions of the wave propulsion system, generally adapted to the dimensions of the vessel, can be significant given the limited space in a port or near a mooring quay.
[0107] Furthermore, this disengagement does not reduce the useful surface area of the deck (such as the main deck for example) located at the rear of the boat.
[0108] In addition, disengaging the wave propulsion system from the water ensures the integrity of the wave system or the vessel when environmental conditions are not conducive to its use, or even guarantees safe docking of the vessel without structural damage.
[0109] Disengagement can also free up space in the event of the boat being towed by another boat.
[0110] For this purpose, the third projection comprising the through opening 210c can be crossed by a towing cable 340. The placement of the flap in the raised configuration can make it possible to free up a space defined by an opening cone starting from the opening and having an opening angle 360 of at least 180 degrees in a plane perpendicular to the median plane XM, and of at least 30 degrees in the median plane XM, preferably 60 degrees in the plane XM. This opening cone can be defined according to the SOLAS standard for the towing of high-tonnage vessels such as LNG carriers for example.
[0111] This third projection comprising a through opening can be used to pass a tow cable to tow the boat / vessel whether in working configuration or in raised configuration. Preferably, towing and use of the tow cable with the third projection is carried out in raised configuration.
[0112] In Figure 3, the deployment of the rods of the hydraulic cylinders 260 is also illustrated when the yoke is moved from a low position to a high position.
[0113] Furthermore, when the shutter is placed in the raised configuration, the locking device can make it possible to release the stress exerted on the lifting actuation means 260 (e.g. hydraulic cylinders or irreversible screw-nut system), and to prevent any fall of the shutter and the articulated assembly in the event of failure of the lifting actuation means.
[0114] Advantageously, when the lifting actuation means 260 are one or a plurality of irreversible screw-nut systems, the prevention against any fall of the shutter and of the articulated assembly in the event of failure of the lifting actuation means is significantly improved via the irreversibility of the irreversible screw-nut system.
[0115] In one or more embodiments, the angle of rotation between the low position and the high position of the yoke around the axis of the journals (A1, A1') is greater than 70 degrees, preferably greater than 105 degrees, and even more preferably greater than 120 degrees.
[0116] Figure 4 illustrates the kinematics of the propulsion flap under the action of the ship's pitching and waves in working configuration.
[0117] During the rotary movement, generated by the movement of the waves, of the flap arm(s) (and therefore of the propulsion flap) around the pivot links A2, A3, A2', A3', the flap arm(s) and the propulsion flap can be returned to their original position via the set(s) of motion control elements causing an oscillating movement of the flap conducive to the propulsion of the ship.
[0118] The flap arm may comprise at least one means 410 for adjusting the angle between the flap and the flap arm in a perpendicular plane and along the transverse direction of the flap (or in the XM plane). For example, the adjustment means may be one or more hydraulic cylinders (e.g. linear cylinder) each cylinder of which is in pivot connection A8 with the flap arm, and the rod of each cylinder is in pivot connection A9 with the flap. Thus, it is possible to actively adjust the angle between the flap and the flap arm(s) during wave phenomena, making it possible to optimize the propulsive effect of the wave-powered system. Injecting energy into this flap / horizontal arm connection also makes it possible to more clearly reveal a resonance in the oscillation of the mechanical system and therefore a propulsive performance peak.
[0119] Figure 5 illustrates the wave propulsion system mounted in translation on a boat.
[0120] In this embodiment, the yoke 115 can be mounted in translation on the base 110 fixed to the boat 103.
[0121] The articulated assembly and the propulsion principle remain the same as in the embodiments presented previously, except that the shutter can be placed in the working configuration or the raised configuration by a translational movement along the Z direction or following an inclined ramp.
[0122] In this embodiment, the locking device can be placed along the base at different levels to secure the hinged assembly at different heights corresponding to different heights of the propulsion flap.
Claims
Claims
1. A wave propulsion system (100) configured to be installed on a boat, said system comprising a flap (105), said wave propulsion system being able to place the flap in a working configuration, where the flap is submerged in water, or in a raised configuration, where the flap is out of the water, the wave propulsion system comprising: a base (110) mounted at the rear of the boat (103), the base being connected to a yoke (115) movable relative to the base, the yoke being arranged so as to place the flap in the working configuration or the raised configuration, an articulated assembly (120) connecting the flap (105) to said yoke (110), the articulated assembly being arranged so as to allow oscillation of the flap under the action of the movements of the boat caused by the movements of the waves when said flap is in the working configuration,a lifting actuating means (260) for switching from the working configuration to the raised configuration.,
2. The system of claim 1, wherein the yoke is rotatably mounted on the base between a low position and a high position.
3. System according to the preceding claim, in which the boat comprises a longitudinal direction X and in which the base comprises a first bearing (210a) and a second bearing (210b), the first and second bearings being arranged on either side of a median plane (XM), the yoke being (115) connected (A1; A1 ') to the first and second bearings by respective journals.
4. System according to the preceding claim, in which the angle of rotation between the low position and the high position of the yoke around the axis of the journals (A1, A1') is greater than 70 degrees, preferably greater than 105 degrees, and even more preferably greater than 120 degrees.
5. System according to one of the preceding claims wherein the articulated assembly comprises at least a first arm (220a) and a second arm (220b) connected to the yoke and to at least one flap arm (230a) by respective pivot links (A2, A2', A3, A3'), said first arm and said second arm being arranged so as to cross and pivot relative to each other in a plane perpendicular to the flap and along the longitudinal direction of the boat X, said flap arm (230a) being connected to the flap (105) by at least one pivot link (A4) with the flap, the articulated assembly being configured so that the oscillation of the flap under the action of the boat results simultaneously of the work of the first arm and of the second by pivoting relative to the yoke by the pivot connections (A2', A3)' and relative to the shutter arm by the pivot connections (A2, A3), as well as of the work of the shutter relative to the shutter arm around the pivot connection (A4) between the shutter (105) and said at least one shutter arm (230a).
6. System according to the preceding claim, in which the articulated assembly comprises first and second arms connected respectively to one or a plurality of shutter arms and to the yoke, and which are arranged symmetrically with respect to the median plane (XM).
7. System according to the preceding claim 5 or 6, wherein the articulated assembly comprises at least a first (240a, 240b) set of active and / or passive motion control elements and at least a second set of active and / or passive motion control elements (245a, 245b) configured to control the pivoting of the first arm and the second arm respectively, said first set of motion control elements (240a, 240b) being arranged between the yoke (115) and the first arm (220a), and said second set (245a, 245b) of motion control elements being arranged between the yoke (115) and the second arm (220b).
8. System according to the preceding claim, wherein the first set of motion control elements and / or the second set of motion control elements are passive, each set of motion control elements respectively comprises a first return spring (240a, 245a) and a second return spring (240b, 245b).
9. System according to one of claims 7 to 8, wherein the first set of motion control elements and / or the second set of motion control elements are active, each set of motion control elements respectively comprises a first cylinder (240a, 245a) and a second cylinder (240b, 245b).
10. A system according to any preceding claim, wherein said base comprises a guide member for guiding a towing cable (340).
11. System according to the preceding claim, wherein the guide element is formed as a through opening, and when the shutter is placed in the raised configuration, a space is released and which is defined by an opening cone starting from said opening, said opening cone (360) being defined by an opening angle of at least 180 degrees in a plane perpendicular to the median plane XM, and at least 30 degrees in the median plane XM, preferably at least 60 degrees in the median plane XM.
12. System according to any one of the preceding claims, in which the lifting actuating means (260) is at least one hydraulic cylinder or at least one electric cylinder or at least one screw-nut system.
13. A system according to any preceding claim, wherein the wave propulsion system comprises at least one locking device for locking the flap in the working configuration or the raised configuration.
14. System according to any one of the preceding claims, in which the flap has a rectangular or triangular or trapezoidal or ellipsoidal shape in the XY plane, and a symmetrical NACA profile type shape in the XM plane.
15. A system according to any one of the preceding claims 5 to 13, wherein the shutter arm comprises at least one means (410) for actively adjusting an angle between the shutter and the shutter arm along a plane perpendicular to the shutter and along the transverse direction of the shutter.
16. An assembly comprising a system according to any one of the preceding claims and a boat, said system being mounted at the rear of the boat, preferably at the stern of the boat.
17. An assembly according to the preceding claim, wherein the base is mounted on the rear external surface of the hull of the boat at the stern, the base being positioned so as to be below the deck of the boat and above the water, so that the yoke is permanently out of the water, and so that in the raised configuration, the hinged assembly and the flap are placed completely out of the water without reducing the surface area of the deck of the boat.
18. An assembly according to claim 16 or claim 17, wherein the overall dimensions of the system are entirely included within the width of the boat.
19. An assembly according to the preceding claim in which the boat is a cargo ship or a passenger ship.