Marine wind power propulsion device

Abstract

The present invention relates to a marine wind propulsion device using a rotary wing, which can be used for retrofit / refurbished and newly built vessels, thereby reducing the fossil fuel consumption of the vessel by about 50%. A marine wind propulsion device comprising a mast extending in a vertical direction and a rotor comprising a rotary wing configured to rotate about an axis perpendicular to the vertical direction, the rotor being carried by the mast and comprising an orienting device for orienting the rotor about the vertical direction, the rotating wings can generate sail thrust used for pushing the ship and driving torque around the axis when subjected to the wind action.

Description

Technical Field

[0001] The present invention belongs to the field of ship propulsion, in particular the field of wind propulsion, and can be used as a main propulsion means or an auxiliary propulsion means.

[0002] The present invention can be applied to existing ships, or implemented as part of ship construction, or implemented gradually to reduce the fossil fuel consumption of ships. Background Art

[0003] 90% of world trade is carried out by ships, which are powered by fossil fuels and emit about 3% of global greenhouse gases.

[0004] Today, about 7% of the world's oil is used to propel these ships.

[0005] International regulations aim for reductions in CO2 emissions per tonne-km of at least 40%, 70% and close to 100% in 2030, 2040 and 2050, compared to a 2008 reference value.

[0006] However, total energy consumption for maritime transport is nearly 3,000 terawatt hours per year, so solutions using low-carbon emission fuels such as agrofuels or synthetic fuels must be complemented by solutions aimed at reducing energy consumption on board ships.

[0007] Using wind propulsion is a well-considered solution under development, but it faces several difficulties.

[0008] First of all, in terms of tonnage, the ships in question had a carrying capacity hundreds of times greater than the largest sailing ships ever built.

[0009] Logistics constraints: Vessels should deliver cargo within a predictable timeframe that is not affected by wind damage.

[0010] Therefore, the solutions implemented so far have been to use wind propulsion units as an auxiliary means of propulsion, while the vessel retains its main engine.

[0011] Wind propulsion systems employed to date primarily include "kites," rigid sails, deployable sails (conventional or inflatable), thick aerodynamic shapes, and Flettner rotors utilizing the Magnus effect.

[0012] These systems can reduce the vessel's consumption, but they also present technical and operational limitations: they require a large surface area to generate propulsion, may require many masts, making port operations difficult, they can restrict visibility, and in some ports and navigation areas, they can make entry and exit difficult due to the need to pass under bridges, they can require maintenance and replacement of parts that are subject to significant wear, and they are less effective in shallow apparent winds, especially headwinds. When they cannot be lowered or retracted, they can constitute significant additional air resistance and, in these conditions, lead to additional consumption, which is then propulsed by the main engine.

[0013] Some systems, such as Flettner rotors or thick aerodynamic profiles, require energy to operate under most operating conditions, limiting their overall efficiency.

[0014] Therefore, these wind propulsion systems in the prior art, when used on relatively large cargo ships, may have a certain efficiency in downwind conditions (such efficiency can be obtained on certain sea routes and / or by reducing the ship's operating speed), but may not save more than 30% of the ship's consumption while maintaining an acceptable operating speed on various routes. Summary of the Invention

[0015] The object of the present invention is to address the shortcomings of the prior art and achieve greater emission reduction effects than the prior art equipment under more diverse wind forces and a wider range of operating conditions. To this end, the present invention relates to a ship comprising a displacement hull and a maneuverable propulsion device, the ship generating hydrodynamic resistance at a reference forward speed, comprising a wind propulsion device comprising a mast extending in a vertical direction, a rotor consisting of rotating wings, the rotating wings being capable of rotating around an axis perpendicular to the vertical direction, the rotor being carried by the mast and comprising an orienting device configured to orient the rotor around the vertical direction, wherein the rotating wings are capable of generating sail thrust to propel the ship when acted upon by wind, and generating a driving torque around the axis.

[0016] This wind propulsion device is therefore similar to a wind turbine, except that it can simultaneously and optimally use sail thrust and drive torque, thereby reducing the ship's fuel consumption by generating steerable sail thrust to propel the ship forward, while retaining the possibility of generating drive torque, in particular to generate energy that can in turn be used for ship propulsion or other purposes. Therefore, regardless of the wind direction, this wind propulsion device, whether used as main propulsion device or auxiliary device, can effectively reduce fuel consumption.

[0017] Compared with the wind propulsion devices of the prior art, these characteristics enable the wind propulsion device to generate propulsion assistance, or even the entire propulsion force of the ship, under more wind conditions, especially but not limited to small-angle headwind conditions, and even under tailwind conditions. At the same time, compared with the wind propulsion devices of the prior art, the area occupied to generate equivalent sail thrust is smaller.

[0018] Compared with the devices of the prior art, the device significantly reduces the obstruction to visibility and also significantly reduces the air resistance when the device is not in use.

[0019] The vessel can be realized according to some of the embodiments and variations thereof described below, which can be considered individually or in any technically feasible combination.

[0020] According to some exemplary embodiments, the length of the hull is less than 150 meters, the reference forward speed is between 5 knots and 20 knots, and the configuration of the wind propulsion device is such that the sail thrust is greater than or equal to 50% of the hydrodynamic resistance at the reference forward speed under a tailwind condition where the true wind speed is 2.5 times the reference forward speed.

[0021] According to some other embodiments, the hull length is greater than 150 meters, the reference forward speed is between 5 knots and 20 knots, and under tailwind conditions with a true wind speed of 2.5 times the reference forward speed, the sail thrust is greater than or equal to 30% of the hydrodynamic resistance at the reference forward speed.

[0022] The wind propulsion device may consist of two masts spaced longitudinally apart.

[0023] There may also be a lateral distance between the two masts.

[0024] According to some exemplary embodiments, the mast may carry a rotor having a rotor wing comprised of two blades, one blade including an aerodynamic airfoil profile, the rotor including a mechanism for orienting the blades about an axis relative to the rotor.

[0025] The vessel may include batteries and the wind propulsion device may include a generator driven by the rotor blades.

[0026] According to some embodiments, a wind propulsion device includes a nacelle connected to a mast and carrying a rotor, with a generator mounted in the nacelle.

[0027] According to other embodiments, the generator may be mounted within the mast or on the deck and connected to the rotor wing via a mechanical or hydraulic connector configured to transfer the mechanical rotational power of the rotor wing to drive the generator.

[0028] The motorised propulsion means may comprise an electric motor.

[0029] Electric motors may be reversible, capable of generating electricity when driven.

[0030] The wind propulsion device may include an electric drive device for driving the rotor blades so that the rotor blades operate as air thrusters.

[0031] According to some embodiments, the wind propulsion device may include a plurality of rotors distributed on a mast in a vertical direction.

[0032] The mast may include a telescopic section.

[0033] According to some variants, the mast may comprise a tiltable portion about a tilting axis perpendicular to the vertical.

[0034] A portion of the mast may be contoured to a shape that reduces the mast's air resistance.

[0035] The latter configuration also allows for additional sail thrust to be obtained by using the mast as a rigid wing and adjusting the mast's orientation appropriately according to wind and sailing conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present invention can be based on the following Figures 1 to 14D The present invention is implemented by the embodiment shown, but is in no way limited thereto, wherein:

[0037] Figure 1 shows a schematic cross-sectional view of a vessel employing wind propulsion in a downwind sailing configuration;

[0038] Figure 2 shows a schematic cross-sectional view of a vessel employing wind propulsion in an upwind sailing configuration;

[0039] Figure 3 A flowchart illustrating a method for selecting a wind propulsion device suitable for a ship is shown;

[0040] Figure 4 A side view of a cargo ship using a wind propulsion device is shown, including an enlarged cross-sectional view of a blade of the wind propulsion device;

[0041] Figure 5 A side view of a tanker using a wind propulsion device is shown;

[0042] Figure 6 A schematic longitudinal section of a wind propulsion device is shown, wherein a generator is installed in a mast;

[0043] Figure 7 Shown Figure 4 A top view of a cargo ship in FIG, wherein the mast of a wind propulsion device is orthographically projected onto the deck;

[0044] Figure 8 A front view showing the equivalence of single and multiple rotors in terms of sail thrust is shown;

[0045] Figure 9 A perspective view of a wind propulsion device consisting of a multi-rotor mast is shown;

[0046] Figure 10 Shown Figure 9 a ship with its mast retracted;

[0047] Figure 11 A schematic diagram showing the power flow and distribution between propulsion devices of a ship using a wind propulsion device;

[0048] Figure 12A 、 Figure 12B 、 Figure 12C and Figure 12D shows a top view schematic diagram of some configurations of a wind propulsion system according to wind direction;

[0049] Figure 13 Shown Figure 4 A top view of a cargo ship in FIG, wherein the direction of the rotor is relative to the longitudinal direction of the ship;

[0050] Figure 14A 、 Figure 14B 、 Figure 14C and Figure 14D Schematic top view showing some configurations of a wind propulsion system consisting of two masts according to wind direction. DETAILED DESCRIPTION

[0051] definition

[0052] A vessel is a vessel the normal purpose of which is to travel over distances within predictable times and / or at a controllable speed, in particular for the transport of goods or passengers, or for the performance of a specific operation while underway, such as fishing, prospecting or laying submarine cables, to name a few non-exhaustive examples and regardless of wind conditions.

[0053] The vertical direction is perpendicular to the floating surface of the ship.

[0054] Sail thrust is the mechanical thrust generated by a rotor blade perpendicular to its axis when acted upon by wind. It does not generate driving torque or electricity. This mechanical thrust exists when the rotor blade is rotating freely about its axis, or when the wind is acting upon the rotor blade to generate driving torque and operate as a wind turbine.

[0055] Air propeller refers to a mode of operation in which the rotor is rotated by the engine and behaves like an airplane propeller.

[0056] Real wind refers to the wind when it blows, which can be represented by a vector. The direction of the vector is the wind direction, and the magnitude of the vector is the wind speed.

[0057] The apparent wind speed is the vector sum of the true wind speed and the ship's forward speed vector. The latter is represented by a vector whose direction is the direction of the ship and whose magnitude is the ship's forward speed. The apparent wind speed is the wind speed felt on the ship's deck.

[0058] Both hydrodynamic drag and aerodynamic drag are forces that oppose the motion of a ship.

[0059] Propulsion force is the projection in the direction of ship movement, which is the result of subtracting resistance from the thrust generated by the propulsion device.

[0060] While under certain specific conditions wind propulsion can cover 100% of a vessel’s propulsion needs, when converting / renovating existing vessels already equipped with propulsion (usually internal combustion engines), the goal is to provide a propulsion auxiliary that reduces total consumption by at least 30%, and preferably at least 50%.

[0061] Wind propulsion units are therefore designed to work alongside the propulsion units already on board the vessel in order to reduce their consumption.

[0062] like Figure 1 As shown, according to some schematic and exemplary embodiments, a ship 100 using a wind propulsion device includes a displacement hull 10 on which a motorized propulsion device is installed, for example, in the form of an internal combustion engine 20 driving a marine propeller 21.

[0063] The resistance of a ship depends on the ship's forward speed and the wind force it is subject to. The total resistance of a ship includes:

[0064] - resistance of the hull, superstructure and appendages;

[0065] - resistance of hydrodynamic propulsion devices;

[0066] - Resistance of wind propulsion devices.

[0067] As is known to those skilled in the art, propulsion devices, whether hydrodynamic (propeller 21) or aerodynamic (rotating wings 115), may produce primarily thrust and / or drag, depending on how they are used.

[0068] The vessel includes a wind propulsion device 101 , which consists of a mast 111 extending in a vertical direction 110 relative to the hull. A rotor 115 is mounted on the mast 111 , and the rotor 115 is rotatable around an axis 116 perpendicular to the vertical direction 110 .

[0069] According to this exemplary embodiment, the rotor is mounted in a nacelle 120 which is pivotally connected about a vertical axis at the top of a mast 111 .

[0070] The rotor comprises blades 1151, 1152 having an airfoil shape, which can be oriented about an axis 117 substantially perpendicular to the axis 116 of the rotor by a suitable mechanism, thereby changing the pitch angle of the rotor.

[0071] According to this exemplary embodiment, nacelle 120 includes a generator 121 connected to a battery 130 .

[0072] Thus, according to this exemplary embodiment, the wind propulsion device looks like a wind turbine, but its purpose is different from that of a wind turbine.

[0073] When the wind propulsion device is acted upon by wind 190 with a speed of V0, the wind causes the rotor to rotate, generating a surface that is swept by the blades 1151 and 1152 and V0. 3 Proportional to the rotational power, and to the area swept by the blades and V0 2 Proportional to the thrust of the sail which is substantially perpendicular to the plane of rotation of the rotor.

[0074] If the blades are allowed to rotate freely, that is, the generator 121 does not generate a resistance torque, the rotational power is zero, and the propulsion force comes from the thrust of the sail.

[0075] Conversely, if the blade is blocked from rotating, the rotational power is also zero and the surface exposed to the wind is limited to the blade surface. Therefore, the sail thrust is a function of the orientation of the blade about its axis.

[0076] Between these two extremes, the ratio of sail thrust to rotational power can be adjusted, the latter generating electrical energy to power the battery 130, depending in particular on the orientation of the blade about its axis 117 (pitch) and the apparent wind direction relative to the rotor's axis of rotation.

[0077] Sail thrust can increase the boat speed up to a speed of V 150, so sail thrust and rotational power are actually proportional to the apparent wind speed (V0 – V) (a vector relationship) and should be adjusted accordingly.

[0078] Thus, the thrust from the sails on the rotors 115 can be used to supplement the propulsion of the vessel, while the electricity generated can be stored in batteries.

[0079] According to some simple embodiments, the wind propulsion device assists the propulsion engine by the thrust of the sail to reduce consumption, and the energy generated by the rotational power can be stored in the battery and can be used for purposes other than ship propulsion, such as providing power for the ship's refrigeration unit or any other equipment.

[0080] Figure 2 The configuration in FIG is that the vessel is traveling against a headwind of 290°, with the rotor blades facing the wind direction, and the vessel is traveling at a forward speed of 250° via the propulsion engines. The thrust of the sails on the rotor blades creates air resistance, which hinders the movement of the vessel.

[0081] However, according to the first configuration, this drag can be significantly reduced by stopping the rotation of the rotor and adjusting the direction of the blades appropriately.

[0082] According to the second configuration, the vessel is equipped with electric propulsion motors to assist in vessel propulsion under these conditions.

[0083] According to a first variant, the generator 221 driven by the rotor is reversible and can be used as an electric motor driving the rotor.

[0084] The generator / motor 221 is powered by batteries, which may have previously been charged by the generator / motor 221 operating in generator mode and being driven by the rotor.

[0085] Thus, according to this approach, the rotors can be used as air thrusters, thereby generating propulsion and assisting the propulsion engines or even replacing them in propelling the vessel.

[0086] According to another configuration compatible with the previous one, the vessel is equipped with an electric propulsion motor 230 so that the marine propeller 21 can drive the vessel alone or together with the internal combustion engine 20 .

[0087] In this case, Figure 2 In the configuration, under headwind conditions, the rotor blades can rotate under the action of the wind to generate electrical energy, which is supplied to the electric propulsion motor 230 through the battery. The electric propulsion motor assists the internal combustion engine 20 in propelling the ship, thereby reducing fuel consumption.

[0088] Therefore, the wind propulsion device can assist the ship's propulsion regardless of the wind direction, including headwind conditions.

[0089] The device can also generate and store electrical energy, including when the vessel is at anchor, and can be adjusted to a minimum aerodynamic drag configuration if necessary.

[0090] Figure 3 The wind propulsion system in the vessel can be matched to existing ships in order to reduce fuel consumption by at least 30% and up to 50% in the so-called simplified configuration, and by close to 100% in the so-called complete configuration.

[0091] It therefore offers great flexibility in adapting to existing vessels, depending on their usage and the foreseeable costs of overhauls.

[0092] To this end, according to a first step 310 of data collection, relevant technical information about the vessel may be collected, in particular the vessel's geometrical, hydrodynamic and aerodynamic characteristics, such as:

[0093] - Hull characteristics: length, displacement, location of center of gravity and center of buoyancy;

[0094] -Hydrodynamic drag and aerodynamic drag as a function of cruising speed.

[0095] With these characteristics, it is possible to build a ship model that can be used in simulations.

[0096] In a parallel step 320 of collecting operational constraints, factors such as the maximum permissible height and width, for example, when passing under a bridge or in a canal, and the positioning and footprint of cargo or equipment on deck can be obtained. With this information, the maximum footprint of the wind propulsion system and possible retraction techniques can be determined.

[0097] Finally, the step 330 of acquiring sailing conditions comprises acquiring a target sailing speed, in particular at least one reference cruising speed, characteristics of the propulsion engine and wind conditions in a typical sailing area.

[0098] For example, as a first approximation, winds in the Atlantic are mostly westerly with speeds between 11 m / s and 21 m / s, and similar data are available for all navigation areas.

[0099] Most cargo or passenger ships travel at speeds between 5 and 20 knots (2.57 to 10.29 m / s).

[0100] Although there may be special circumstances, the cost of installing such a wind propulsion system on board a vessel can be repaid within a reasonable operating time through fuel savings.

[0101] Wind propulsion devices can be adapted to different configurations.

[0102] In a first feasibility check, to ensure that sufficient assistance could be provided in all wind and route conditions, thereby reducing emissions by 50%, in the tailwind condition, the rotor blades were perpendicular to the wind direction, and for an average wind speed of V 01 and the reference forward speed of the ship V1, when the true wind speed V 01 When the sail thrust is equal to 2.5 times the forward speed V1, the sail thrust should be at least equal to the hydrodynamic resistance of the ship at the same speed (D H ) part. (V 01 =2.5*V1).

[0103] In addition, when a vessel is equipped with or is intended to be equipped with electric propulsion (whether aerodynamic or hydrodynamic), at an average wind speed of V02 In the case of the rotor, the electric power generated when the ship moves forward at the second forward speed V2 is (V 02 ±V2) 3 Proportional, depending on the direction of the wind relative to the speed of travel, the two speeds add up in headwind conditions.

[0104] Under these conditions, the minimum sweep area of ​​the rotor blades of a wind propulsion device can be determined by the following formula:

[0105] Formula 1

[0106]

[0107] Formula 2

[0108]

[0109] Where A is the surface swept by the rotor blades of the wind propulsion device, ρ is the air density, T is the sail thrust, P is the rotational power, and C T and C P is a coefficient that can be obtained from tables, databases or numerical calculations and is applicable to different implementation schemes of wind propulsion systems.

[0110] Therefore, under normal sailing conditions, the direction of the rotor blades is different from the direction perpendicular to the wind direction, and the operation of the wind propulsion device involves determining the optimal position of the rotor and blade pitch to generate maximum propulsion force.

[0111] When presizing and selecting characteristics of wind propulsion devices, the sail thrust under downwind conditions is considered as a sizing parameter.

[0112] As shown below, this configuration is rarely used in actual navigation situations and is only a notable configuration used to determine the minimum performance configuration of wind propulsion equipment for initial selection.

[0113] For ships less than 150 meters in length, this ratio may be equal to 50% (T>0.5D H ), for ships with a length greater than 150 meters, the ratio may be equal to 30% (T>0.3D H ). These limits are theoretical and are used for preliminary sizing.

[0114] One reason for this is that large ships can be equipped with two masts, each with a rotor. Outside of certain operating points, including those mentioned above, only one rotor is truly effective due to aerodynamic interference between the rotors. In other cases, the thrust generated by wind propulsion is significantly increased.

[0115] However, if there are more than two masts, difficulties arise with regard to deck occupancy and aerodynamic interference of one rotor with another.

[0116] For small vessels with a length of less than 100 meters, installing two masts is usually difficult, but not always impossible; for medium-sized vessels with a length between 100 and 150 meters, considering the advantages of two masts, the technical solution of two masts carrying the rotors is usually preferred.

[0117] The examples listed below show that these minimum requirements can easily be exceeded.

[0118] Combined with other constraints, the most appropriate implementation plan can be selected.

[0119] One rotor per mast

[0120] According to a first embodiment, the wind propulsion device comprises a single rotor on each mast, e.g. Figure 4 and Figure 5 As shown, Figure 4 For example of a bulk carrier 400, Figure 5 An example of a Suez-class tanker 500.

[0121] See also Figure 4 and Figure 5 For ships with a length greater than or equal to 150 meters, the wind propulsion device consists of two masts, each of which has a rotor 411, 412, 511, 512 and is longitudinally distributed on the hull.

[0122] There is a certain longitudinal distance l between the two masts 411 and 412 and between the two masts 511 and 512. Taking into account the structural limitations of the implementation and other limitations specific to the ship, it is preferred that this distance be maximized.

[0123] The total distance between the two masts is at least 1.5 times the diameter of the largest rotor to limit aerodynamic interference between the rotors, since in operation (see Figure 13 ), the rotor is typically at an angle 1320 to the longitudinal direction 1310.

[0124] According to this exemplary embodiment, the rotor is rotatably connected to the top of the mast and includes a nacelle that houses various control mechanisms, particularly the pitch control of the rotor blades, as well as a motor-generator driven by the rotor. The generator can be reversible and can also be used as an electric motor to drive the rotor, which can then operate in air propeller mode.

[0125] In addition, a pivot connection about a vertical axis may also be provided at the bottom of the mast or at a portion of the mast close to the bottom.

[0126] The mast portion 413 may be designed in a shape that limits its aerodynamic drag.

[0127] Each rotor is composed of two blades 4151 and 4152, and two blades 5151 and 5152, whose cross sections 415 and 416 follow the aerodynamic profile of the wing. They are shown to be solid here, but may also be hollow.

[0128] The aerodynamic shape of the blades is optimized to generate sail thrust, which is controlled by a variable pitch mechanism.

[0129] In the case where the rotor is driven solely by wind power, a portion of the blades 415 may be asymmetrical, with the blades being twisted along their length.

[0130] In the case where the rotor also functions as an air propeller, a portion 416 of the blades may be symmetrical and the blades may not be twisted.

[0131] This dual-blade configuration enables:

[0132] - Reduce the lateral footprint of the wind propulsion device and its aerodynamic drag by aligning the blades with the mast;

[0133] - Reduce the overall height of the wind propulsion device by aligning the blades perpendicular to the mast.

[0134] Therefore, aligning the blades with the mast can reduce the impact of the wind propulsion device on visibility, especially when maneuvering, without hindering loading and unloading operations by cranes, or setting the wind propulsion device in a configuration that can be tilted towards the ship's deck, for example when the ship is passing under a bridge.

[0135] From the previously determined minimum swept surface area, the minimum diameter of the rotor can be derived, and hence the height of the first mast.

[0136] As long as the stability of the vessel remains within an acceptable range, the minimum swept surface area and the corresponding mast height can be increased, thereby improving the potential efficiency of the wind propulsion device. The heights of the two masts 511 and 512 can be different. Similarly, the two rotors can also be equipped with rotor blades of different diameters.

[0137] The stability of a vessel depends on its mass, the position of its centre of gravity relative to the centre of buoyancy, the characteristics of the hull (primarily related to the application altitude and the strength of the sail thrust), and secondly on the displacement of the centre of gravity after the rotor is installed.

[0138] like Figure 6As shown, according to some embodiments, a generator 621, whether of the generator type or the generator / motor type, can be placed on a platform 630 inside the mast 611 to lower the center of gravity of the wind propulsion device. A mechanical connection consisting of a constant velocity joint 625 can drive the generator through the rotor 615, and when the generator type is a generator / motor, it can also drive the rotor in air propeller mode.

[0139] According to some embodiments (not shown), the generator or generator / motor may be mounted on the deck of the vessel and connected to the rotor by a mechanical or hydraulic connection.

[0140] According to other embodiments, the generator and the motor driving the rotor blades to operate as air propellers may be two separate entities, respectively disposed at different locations in the nacelle, inside the mast, or on the deck of the ship.

[0141] Depending on the wind direction, the volume covered by the wind propulsion device is a sphere 490, which should be checked for collision with the ship's structure or cargo on board.

[0142] like Figure 7 As shown, in addition to the solution of orienting the rotating rotor so that the blades are perpendicular to the mast, thereby reducing the overall height of the wind propulsion device when passing under a bridge or other similar situations, according to some embodiments, the mast 411, 412 may include a part that can be tilted about an axis perpendicular to the vertical direction relative to the part where the mast is connected to the hull.

[0143] According to a variant, the tilting connector can be located at or close to the bottom of the mast and the boat deck, or higher up on the mast.

[0144] According to some variants, the tilting connector allows the upper portion of the mast to be tilted relative to the lower portion at an angle between 0° and 180°. At an angle of 0°, the mast is vertical and the two portions are aligned; at an angle of 180°, the two portions are parallel.

[0145] In order to achieve the above tilting, the blades must be aligned with the mast beforehand.

[0146] exist Figure 7 In the example shown, the tilting connector is located at the deck level, and the upper portion can be tilted at a 90° angle to lower the wind propulsion device closer to the deck of the vessel 400.

[0147] To achieve this, the two masts carrying the rotors are offset by a transverse distance e along the width of the ship. This transverse offset also limits the impact of the wind propulsion system on visibility and reduces aerodynamic interference between the rotors on the masts.

[0148] Multi-rotor mast

[0149] like Figure 9 As shown, according to some embodiments, the wind propulsion device 900 may include multiple rotors, where each mast 911 and 912 has five rotors, and the multiple rotors are distributed along the vertical direction of the mast.

[0150] This configuration can disperse the thrust of the sail to different heights of the mast, which has less impact on the stability of the ship when the sail thrust is the same, or can obtain a larger sail thrust within a certain stability limit.

[0151] Depending on the wind direction, the envelope of the volume covered by the wind propulsion device is an ellipse 690, which is also advantageous for implementation on certain types of vessels.

[0152] This configuration also allows for a reduction in the distance between masts, thereby reducing aerodynamic interference, compared to solutions with a single rotor on each mast.

[0153] Therefore, the use of a multi-rotor mast may allow for more than two masts to be provided when the configuration of the vessel is adjusted.

[0154] Figure 8 It is shown that, to a first approximation, from the perspective of sail thrust, multiple rotors of diameter d superimposed on a mast, as long as the trajectories of the rotors are coordinated or almost coordinated, generate a sail thrust of the same order of magnitude as the sail thrust generated by a single rotor with a diameter D equal to the sum of the diameters of the multiple rotors (here N*d).

[0155] Thus, four superimposed rotors (each with a diameter of 15 meters) can generate the same order of magnitude of sail thrust as a single rotor with a diameter of 60 meters.

[0156] Alternatively, the rotor blades of the multiple rotors may not have the same diameter, but the trajectories of the superimposed rotor blades must be intermeshing or quasi-intermeshing, with the minimum distance between the blade tips of two superimposed rotor blades being less than or equal to 1 / 20 of the rotor blade diameter.

[0157] Figure 10 In the embodiment, the masts 611, 612 carrying the multiple rotors may include one or more telescopic sections that allow the masts to be retracted to a lower height after the blades of the rotors are oriented perpendicular to the masts, for example to enable a ship to pass under a bridge.

[0158] Those skilled in the art understand that a mast, whether comprising a single rotor or multiple rotors, may comprise one or more telescopic sections and a tiltable connection relative to another section, and the tiltable connection section and / or the non-tiltable section may comprise a telescopic section.

[0159] As with configurations where each mast consists of one rotor, a pivoting connection about a vertical axis allows the rotors to be oriented relative to the wind. In the case of a multi-rotor mast, this pivoting connection of the rotors about the mast's vertical axis can be implemented individually for each rotor, or the pivoting connection about the vertical axis can be located at the base of the mast, thereby simultaneously determining the orientation of all rotors. These two variants are not mutually exclusive. Each of the multiple rotors on a mast can be individually oriented. This configuration specifically takes into account the fact that, for masts with a height of approximately 100 meters, in some applications, the wind conditions, particularly the wind speed, at the top of the mast may differ from those near the vessel's deck.

[0160] Mast

[0161] Whether it is a single rotor or a multi-rotor, Figure 4 The mast portion 413 may be profiled to limit its aerodynamic drag, or the mast may include an aerodynamic fairing for this purpose.

[0162] In certain embodiments, the mast, especially when it has a device at the top for orienting the nacelle in addition to a device at the bottom of the mast, can be used as a rigid sail by properly orienting it relative to the wind direction, thereby providing additional sail thrust.

[0163] In the case of a multi-rotor mast, in addition to the air propulsion thrust generated by the rotor itself, the operation of the rotor in the air propulsion mode can be coordinated with a special-shaped mast. Under the action of the aerodynamic flow caused by the rotor, in addition to the air propulsion thrust generated by the rotor itself, thrust can also be generated by the mast acting as a wing.

[0164] According to some embodiments, the mast may consist of a lattice structure on which an aerodynamic fairing is mounted.

[0165] motor

[0166] According to some embodiments, the vessel may include an electric propulsion device.

[0167] According to some embodiments, these electric propulsion devices 221 ( Figure 1 ) can drive the rotor, thereby making it operate as an air propeller. This mode of operation can be implemented in both single-rotor configurations and multi-rotor configurations.

[0168] According to some other embodiments, as an alternative or in addition to the latter, the electric propulsion device includes an electric motor 230 ( Figure 1 ), used to drive at least one marine propeller 21 ( Figure 1 ), providing hydrodynamic propulsion for ships.

[0169] According to some exemplary embodiments, the electric motor driving the marine propeller may be pre-existing, for example, when the vessel includes an internal combustion engine (diesel or gas turbine) coupled to the electric motor, or the electric motor is installed when the vessel is converted and a wind propulsion device is installed.

[0170] As a non-limiting example, this electrical device, known as a PTO / PTI, can be installed on an existing propeller shaft and can work alongside or in addition to an internal combustion engine, providing up to 100% of the required propulsion. It can also be used for regenerative braking, absorbing mechanical energy and converting it into electrical energy, which can be stored in batteries or used directly onboard. It can also be used in generator mode, driven by the internal combustion engine or by the marine propeller spinning freely under the hydrodynamic forces generated by the vessel's motion or water currents.

[0171] For example, Asea Brown Boveri Ltd. of Sweden We sell PTO / PTI units suitable for installation on existing vessels with a power of up to 6 MW.

[0172] Figure 11 In accordance with a so-called complete system, the electrical energy generated by the rotor via the generator passes through a current rectifier 720 and is then directed to a power distributor 730 .

[0173] The power divider may distribute power between the PTO / PTI device, the battery, and onboard equipment 740 (if applicable).

[0174] The power divider can also direct electrical power to an electric motor or generator / motor to drive the rotor blades operating in air propeller mode.

[0175] The PTO / PTI device can drive the marine propeller 21 independently or in addition to the internal combustion engine and provide power to the marine propeller 21 through the transmission shaft 750 .

[0176] The PTO / PTI arrangement may also generate electrical energy, driven by a drive shaft 750 which is driven by the marine propeller 21, such as in the case of regenerative braking, or by the internal combustion engine.

[0177] The electrical energy generated by the PTO / PTI device can be directly transmitted to the power distributor 730 and distributed according to the demand related to the navigation conditions.

[0178] To this end, the control device 790 composed of a control program can control various power sources and their distribution according to navigation conditions to maintain conditions with minimum greenhouse gas emissions.

[0179] run

[0180] FIG. 12A to FIG. 12BExamples of the operation of a wind propulsion device under different wind conditions are shown. These wind conditions correspond to the usual operating conditions of a wind propulsion device, but exclude tailwind and headwind, and the rotor forms an angle α with respect to the apparent wind direction. Although the wind propulsion device can operate under these conditions, they are not the usual operating conditions.

[0181] In tailwind, headwind, leeward and crosswind conditions, the best results are usually achieved when the rotors are oriented approximately perpendicular to the true wind direction, but this is not an absolute rule. In upwind conditions, the rotors can be oriented approximately parallel to the axis of the vessel.

[0182] like Figure 13 As shown, when the wind propulsion device includes two masts with rotors, the direction of the rotor blades is not perpendicular to the longitudinal direction 1310 of the hull, which greatly limits the aerodynamic interference of the rotor of one mast on the rotor of the other mast, including in sailing conditions with wind and wind.

[0183] The rotor blades are steered relative to the mast to rotate in any direction with the wind. By adjusting this direction and the blade pitch, the optimum conditions can be found to generate propulsion in all wind conditions.

[0184] In all cases shown, the rotor 115 is oriented at an angle α to the direction of the apparent wind 1195. The vector representing the apparent wind is the vector sum of the true wind vector 1190 and the vessel's velocity vector 1150.

[0185] exist Figure 12A In this case, the vector 11951 representing the apparent wind is perpendicular to the direction of movement 150 and the ship speed 11501. In this case, the rotor can rotate freely and generate the sail thrust 11911, which acts as the propulsion force T A Projected onto the moving direction 150.

[0186] Figure 12B In the figure, the projection of the vector 11952 representing the apparent wind direction in the direction of the ship's motion is parallel to the motion velocity vector 11502. In this case, the rotor blades can act as sails to generate sail thrust 11912, and can also act as wind turbines to generate torque 11922 and rotational power, which are converted into electrical energy to power the PTO / PTI type electric motor, generating hydrodynamic thrust by driving the ship's propeller of the electric propulsion device. Propulsion force T A It is the sum of the hydrodynamic thrust of the ship's propeller and the projection of the sail thrust 11912 in the ship's moving direction 150. In addition, all or part of the electricity generated by the rotor can be used to charge the battery.

[0187] Figure 12CIn the example, when sailing upwind, the projection of the apparent wind vector 11953 onto the vessel's direction of motion 150 is opposite to the vessel's speed 11503. In this situation, the wind propulsion device functions as a wind turbine, generating torque 11923 and rotational power, which is converted into electrical energy to power a PTO / PTI-type electric motor to assist the maneuvering propulsion device. The wind propulsion device generates sail thrust 11913, which is projected in the vessel's direction of motion, opposite to the vessel's forward direction. This aerodynamic drag is less than the electrical power generated, so the wind propulsion device generates power.

[0188] In extreme cases, especially in headwind conditions, the wind propulsion device can be configured to minimize aerodynamic drag, for example, by aligning the blades of the rotor 115 with the mast and stopping its rotation. The vessel can then be moved by the electric motor, which draws its power from the battery.

[0189] Most vessels with wind propulsion installed can accommodate a battery with a capacity of several megawatt hours, which can power the PTO / PTI unit for several hours when used to assist or directly propel the vessel.

[0190] Figure 12D The rotor blades can be driven to rotate by drawing energy from batteries or other means, and can generate aerodynamic thrust (11914) to generate propulsion force. In addition, an electric device driven by a PTO / PTI device or an internal combustion engine can also generate additional propulsion force.

[0191] When a vessel is equipped with both a PTO / PTI unit and an aerofoil propulsion unit capable of operating in air thruster mode, both units may be used simultaneously.

[0192] Furthermore, to reduce greenhouse gas emissions and other pollutants, internal combustion engines can be combined with wind propulsion to propel the vessel or generate electricity via PTO / PTI units, in particular to charge batteries.

[0193] It is practically impossible to repeatedly stop and restart a large internal combustion engine. Therefore, wind propulsion, especially for large ships, can keep the internal combustion engine running below a power threshold.

[0194] The switch from one operating mode to another is made according to the wind direction, in particular by adjusting the orientation of the rotor, and the distribution of the generated and consumed power by the power divider.

[0195] 14A to 14C Shows the results of two similar Figure 4The following are operational examples of a vessel with a single rotor mast, the characteristics of which are given in Table 1. In particular, the figures show examples of rotor orientations under these conditions. In all cases, the hydrodynamic drag of the hull at 12 knots is 153 kN.

[0196] like Figure 14A As shown, under upwind sailing conditions, the forward speed of the vessel 1150 is 12 knots, the true wind speed 1191 is 20 knots, and the wind direction is 40° to the moving direction of the vessel.

[0197] In this scenario, the rotor rotates and generates 1 MW of electricity. The rotor's angle α with the apparent wind (1195°) is approximately 30°, resulting in an aerodynamic drag of approximately 8 kilonewtons. The effect of this force on the hull in the ship's direction of motion creates an additional drag of 11 kilonewtons due to drift and heeling. This power is supplemented by batteries or the internal combustion engine, providing 1.1 MW of power to the ship's propellers, generating 172 kilonewtons of thrust. Taking into account electrical and mechanical losses, the wind propulsion system achieves a 46% reduction in propulsion power in this scenario.

[0198] like Figure 14B As shown, under upwind sailing conditions, the forward speed of the vessel 1150 is 12 knots, the true wind speed 1191 is 30 knots, and the wind direction is 35° to the moving direction of the vessel.

[0199] The rotor is angled 40° to the apparent wind to limit aerodynamic drag in the direction of the ship's motion, which is approximately 64 kilonewtons. This drag exerts an additional 12 kilonewtons on the hull. The rotor generates 2.6 megawatts of electricity, which drives the ship's propeller. Taking into account losses, the propeller's thrust is 1.4 megawatts, or 230 kilonewtons. In this configuration, the wind propulsion system generates 100% of the power required to propel the ship.

[0200] like Figure 14C As shown, under crosswind sailing conditions, the forward speed 1150 of the ship is 12 knots, the true wind speed 1191 is 30 knots, and the wind direction is 90° to the moving direction of the ship.

[0201] The rotor can be angled 42° to the apparent wind direction (1195°). The rotor generates a total sail thrust of 165 kilonewtons. This thrust contributes an additional 12 kilonewtons of hull resistance, making the sail thrust sufficient to propel the ship. In addition, the rotor generates 2.2 megawatts of electricity, which can be stored in batteries, for example. Therefore, after accounting for electrical and mechanical losses, the wind propulsion system generates 243% of the auxiliary power.

[0202] like Figure 14DAs shown, under upwind sailing conditions, the forward speed of the vessel 1150 is 12 knots, the true wind speed 1191 is 20 knots, and the wind direction is 65° relative to the moving direction of the vessel.

[0203] With the rotor angled 30° to the apparent wind, it generates 73 kilonewtons of sail thrust and 0.9 megawatts of electrical power. The sail thrust generates an additional 12 kilonewtons of hull drag. The electrical energy generated by the rotor is fed into the electric propulsion system, which, taking into account electrical and mechanical losses, produces 0.6 megawatts of propulsion power and 92 kilonewtons of thrust. This results in an assist ratio of 99%.

[0204] These examples show that the wind propulsion device can provide a large proportion of assistance to the ship's propulsion device, and the assistance ratio can exceed 100% even when moving into the wind.

[0205] Therefore, by selecting the operating mode of the wind propulsion device according to the wind strength, the operating power of the internal combustion engine can be controlled below a specified threshold, minimizing greenhouse gas emissions and other pollutants while maintaining the battery charge at an ideal level.

[0206] Back to Figure 3 ,In the size presetting step 340, the constraints are analyzed, especially the stability constraints.

[0207] In the design step 350 , the characteristics of the wind propulsion device and, if applicable, the characteristics of the PTO / PTI device may be refined based on initial constraints and by simulating operating conditions.

[0208] Based on the results of the simulation and design steps, the performance of the integrated system is summarized in the diagram 370, for example a wind propulsion device with two masts, whether it can be operated in air propulsion mode, whether a PTO / PTI device is used, and the level of assistance at a given speed is given according to the wind direction and wind speed. Each polar curve 371, 372, 373, 374 corresponds to the real wind speed.

[0209] As can be seen from the figure, once the wind direction deviates from the vertical axis (downwind-headwind), the level of assistance that can be achieved becomes very significant, reaching 100% or even higher, but under such extreme conditions, the assistance level is still very significant.

[0210] Example

[0211] The following examples demonstrate that, when a vessel is sufficiently large, it is easy to achieve or exceed these minimum conditions. Indeed, the heeling and righting moments determine a vessel's stability under the action of wind propulsion devices, and therefore impose structural limits on the height and power of these devices. Height and power are proportional to the square and cube of the vessel's length, respectively. Therefore, for vessels over 100 meters in length, the installed devices must always produce at least 50% of the propulsion assist. The remaining limitations are primarily related to floor space and cost.

[0212] The first exemplary embodiment is Figure 4 The following table summarizes the characteristics of the bulk carriers shown:

[0213] Table 1

[0214] length 138 meters beam 18 meters Draft 6.5 meters Cruising speed 12 sections Displacement 11,570 tons Deadweight 8.210 tons Gross tonnage 7.548 tons Engine power (electric) 2700 kilowatts

[0215] An example of a wind propulsion system for this vessel would consist of two single-rotor masts with the following characteristics:

[0216] Table 2

[0217] Rotor diameter 60 meters Mast height 43.5 meters Number of blades per rotor (symmetrical profile) 2 Total rotor power 3000 kilowatts

[0218] At a forward speed of 12 knots, the hull generates a drag of 153 kilonewtons.

[0219] In tailwind conditions (similar to Figure 1 ), with a true wind speed of 30 knots, or 2.5 times the ship's forward speed, the wind propulsion device can generate a thrust of 294 kN, or almost twice the ship's drag. In practical applications, the motorized marine propeller can be used in regenerative braking to brake the ship and generate energy.

[0220] In tailwind conditions with a true wind speed of 20 knots, that is, a wind speed less than twice the ship's forward speed, the sail thrust generated by the wind propulsion device is 141 kilonewtons, equivalent to 92% of the ship's resistance.

[0221] It is worth noting that in these downwind conditions, the rotor axes of rotation are parallel to the true wind direction, and the aerodynamic interference between the rotors is such that the sail thrust is actually obtained by a single rotor.

[0222] For the same ship, under headwind conditions ( Figure 2 The vessel's forward speed is 8 knots, the true wind speed is 22 knots, and the wind propulsion device acts as a wind turbine, generating 40% of the power required to propel the vessel by the electric propulsion device.

[0223] When the ship's forward speed is 12 knots and the true wind speed is 25 knots, the wind propulsion device acts as a wind turbine and can generate 15% of the power required by the electric propulsion device to propel the ship.

[0224] As with tailwind conditions, headwind conditions can also be unfavorable due to the aerodynamic interference that one rotor creates on the other, so in practice the unit operates in these conditions almost as if there were only one rotor.

[0225] The following embodiments illustrate preset dimensions of wind propulsion devices for different ships based on a single-rotor mast. These preset dimensions can then be refined based on other technical limitations.

[0226] According to the third exemplary embodiment, the corresponding bulk carrier has an overall length of 127 meters, a beam of 21.2 meters, a deadweight tonnage of 14,130 metric tons, is equipped with a 4.4 MW internal combustion engine, and has a maximum speed of 16 knots. The following are the results under different reference speeds and different rotor diameters:

[0227] Table 3

[0228]

[0229]

[0230] These results show that a rotor consisting of 60-meter-diameter rotor blades can achieve a sail thrust of 50% of the drag. Although a single-rotor mast can achieve this effect, if the installation distance between the masts can be guaranteed, using two single-rotor masts with smaller diameter rotor blades may be more advantageous.

[0231] According to the fourth exemplary embodiment, the bulk carrier has an overall length of 171.7 meters, a molded width of 27 meters, a deadweight tonnage of 28,356 metric tons, and an internal combustion engine power of 4.95 MW:

[0232] Table 4

[0233]

[0234] According to this example, the rotor diameter is approximately 80 meters. More precisely, between 60 and 80 meters, a sail thrust of approximately 50% of the resistance is achieved. However, due to the length of the hull (171 meters), it would be difficult to install two rotors with rotors of 80 meters in diameter while ensuring a distance of 1.5 times this diameter between them. However, considering the above-mentioned operating mode, in this case, it would be better to install two 60-meter rotors, where the 60-meter rotor meets the condition of sail thrust equal to 30% of the resistance.

[0235] According to the fifth exemplary embodiment, the bulk carrier has an overall length of 285 meters, a molded width of 45 meters, a deadweight tonnage of 180,915 metric tons, an internal combustion engine power of 15.45 MW, and a maximum speed of 16.7 knots:

[0236] Table 5

[0237]

[0238]

[0239] Therefore, based on this example, we tend to choose rotors with a diameter of between 80 and 100 meters for two rotor blades, or the equivalent for a mast using multiple rotors.

[0240] The above description and embodiments show that the present invention achieves the intended goal and enables ships of any size to use a wind propulsion device consisting of one or two masts, regardless of the route and wind conditions, to reduce internal combustion engine emissions by at least 30%, preferably by at least 50%.

Claims

1. A marine wind propulsion device, arranged in a ship (100, 400, 500, 900), the ship comprising a displacement hull (10) and a maneuvering propulsion device (20), the ship generating hydrodynamic resistance at a reference forward speed (150), the marine wind propulsion device comprising a mast (111, 411, 412, 511, 512, 911, 912) extending in a vertical direction (110) and a rotor, the rotor comprising a rotary wing (115), the rotary wing (115) being configured to rotate about an axis (116) perpendicular to the vertical direction, the rotor being carried by the mast and comprising an orientation device for orienting the rotor about the vertical direction, wherein: The rotary wing (115) is capable of generating a sail thrust (1191) for propelling the ship and a driving torque (1192) around the axis (116) when acted upon by wind.

2. The marine wind propulsion device according to claim 1, wherein: The length of the hull is less than 150 meters, the reference forward speed (150) is between 5 knots and 20 knots, and the configuration of the wind propulsion device is such that the sail thrust (1191) is greater than or equal to 50% of the hydrodynamic resistance at the reference forward speed under a tailwind condition where the actual wind speed is 2.5 times the reference forward speed.

3. The marine wind propulsion device according to claim 1, wherein: The length of the hull is greater than 150 meters, the reference forward speed (150) is between 5 knots and 20 knots, and under a tailwind condition where the true wind speed is 2.5 times the reference forward speed, the sail thrust (1191) is greater than or equal to 30% of the hydrodynamic resistance at the reference forward speed.

4. The marine wind propulsion device according to claim 2 or 3, wherein: The wind propulsion device is composed of two masts (411, 412, 511, 512, 911, 912), with a longitudinal distance (l) between the two masts, and each mast carries at least one rotor.

5. The marine wind propulsion device according to claim 4, wherein: There is a transverse distance (e) between the two masts.

6. The marine wind propulsion device according to claim 1, wherein: The mast carries a rotor having a rotor wing consisting of two blades (4151, 4152), one blade comprising an aerodynamic airfoil section (415, 416), the rotor comprising means for orienting the blades about an axis (117) relative to the rotor.

7. The marine wind propulsion device according to claim 1, comprising a battery (130), wherein: The wind propulsion device includes a generator (121) driven by the rotor (115).

8. The marine wind propulsion device according to claim 7, wherein: The wind propulsion device comprises a nacelle (120) connected to the mast and carrying the rotor, and the generator (121) is installed in the nacelle.

9. The marine wind propulsion device according to claim 8, wherein: The generator (121) is installed in the mast or on the deck and is connected to the rotor blade via a connector (625). The connector is configured to transmit the mechanical rotational power of the rotor blade to drive the generator.

10. The marine wind propulsion device according to claim 7, wherein: The motorized propulsion device includes an electric drive device (230).

11. The marine wind propulsion device according to claim 10, wherein: The electric drive device is reversible and can generate electricity when driven.

12. The marine wind propulsion device according to claim 1, wherein: The wind propulsion device includes a plurality of rotors distributed on the mast (911, 912) along the vertical direction.

13. The marine wind propulsion device according to claim 1, wherein: The mast (911, 912) includes a telescopic portion.

14. The marine wind propulsion device according to claim 1, wherein: The mast (411, 412) comprises a tiltable portion about a tilt axis perpendicular to the vertical direction.

15. The marine wind propulsion device according to claim 1, wherein: A portion of the mast (413) has a profile for reducing the air resistance of the mast.

16. The marine wind propulsion device according to claim 1, wherein: The wind propulsion device includes an electric motor (221) configured to drive the rotor (115) so that the rotor operates as an air propeller.

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