METHOD FOR OPERATING A SHIP, IN PARTICULAR A CARGO SHIP, WITH AT LEAST ONE MAGNUS ROTOR

BACKGROUND

1. Technical Field

The invention concerns a method of operating a ship, in particular a cargo ship, with at least one Magnus rotor.

2. Description of the Related Art

Magnus rotors are also known as Flettner rotors or sailing rotors.

The Magnus effect describes the occurrence of a transverse force, that is to say perpendicularly to the axis and to the afflux flow direction, in the case of a cylinder which rotates about its axis and which has an afflux flow perpendicularly to the axis. The flow around the rotating cylinder can be viewed as a superimposition of a homogeneous flow and an eddy around the body. The irregular distribution of the overall flow affords an asymmetrical distribution of pressure at the cylinder periphery. A ship is thus provided with rotating or turning rotors which in the flow of the wind generate a force perpendicular to the effective wind direction, that is to say the wind direction which is corrected with the highest speed, which force can be used similarly as when sailing to propel the ship. The vertically disposed cylinders rotate about their axis and air flowing thereto from the side then preferably flows in the direction of rotation around the cylinder, by virtue of the surface friction. Therefore on the front side the flow speed is greater and the static pressure is lower so that the ship receives a force in the forward direction.

Such a ship is already known from ‘Die Segelmaschine’ by Claus Dieter Wagner, Ernst Kabel Verlag GmbH, Hamburg, 1991, page 156. That investigated whether a Magnus rotor, also known as a Flettner rotor, can be used as a drive or auxiliary drive for a cargo ship.

What is common to such ships is that the Magnus effect is used only to generate a forward propulsion force for the ship.

BRIEF SUMMARY

In accordance with one embodiment of the invention there is provided a method of operating a ship, in particular a cargo ship, with at least one Magnus rotor, comprising a step of detecting the wind direction of a wind. In addition the method provides for operating the at least one Magnus rotor with a direction of rotation such that the action between the wind and the Magnus rotor provides for generating a force which is directed substantially in opposite relationship to the forward direction of the ship.

In that way it is possible to generate a rearwardly directed force by the Magnus effect in order on the one hand to move the ship rearwardly and on the other hand to produce a braking effect for the ship from a forward movement. In that respect it is precisely the latter that is advantageous as a ship does not have any brake in the actual sense, but its forward movement can only be braked by an oppositely directed rearward movement. Producing such a rearward movement however is not physically possible at all in the case of classic sailing ships by means of the position of the sail and, in the case of ships which have a screw drive, can only be achieved by way of the screw drive. Producing a rearwardly directed screw force however causes unwanted lateral deflections on the part of the ship which change the course thereof and which, in the event of heavy braking, that is to say producing a rearwardly directed screw force at full power, can be so great that those lateral deflections can no longer be compensated for by the rudder assembly.

It is therefore advantageous, in accordance with the method of the invention, to generate a rearwardly directed force by means of the Magnus effect in order thereby to maneuver the ship in reverse without the use of a screw propeller and without the lateral deflection caused by same, or to slow the ship down, or to assist with the rearwardly directed screw force by means of the Magnus effect and thereby to achieve maneuvering or braking more quickly or by virtue of less screw involvement.

The invention also concerns a method of operating a ship, in particular a cargo ship, with at least two Magnus rotors, wherein at least one Magnus rotor is provided on the port side of the ship and at least one Magnus rotor is provided on the starboard side of the ship. The method comprises a step of detecting the direction of a wind. The method further comprises a step of operating the at least one Magnus rotor on the port side of the ship with a direction of rotation such that the action between the wind and the at least one Magnus rotor on the port side of the ship provides for generating a force directed substantially in the direction of the forward direction or the rearward movement of the ship. At the same time the at least one Magnus rotor on the starboard side of the ship is operated with the direction of rotation which is opposite to the direction of rotation of the at least one Magnus rotor on the port side of the ship such that the action between the wind and the at least one Magnus rotor on the starboard side of the ship provides for generating a force directed substantially in opposite relationship to the direction of the force of the at least one Magnus rotor on the port side of the ship.

This method is advantageous as the forces generated in opposite directions on the port side of the ship and the starboard side of the ship produce a turning moment about the center of gravity of the ship. By means of that turning moment, the ship can be turned in a desired direction which can be predetermined by the respective directions of rotation of the port and starboard Magnus rotors. If in that case the ship does not experience any other forwardly or rearwardly directed force, the ship rotates substantially on the spot. If for example a forwardly or rearwardly directed force is generated by a screw, the ship can be deflected in one direction or the other by means of that turning moment without using a rudder assembly for that purpose or for assisting same in the deflection movement. The degree of deflection due to the Magnus effect can be predetermined in that case by the respective speeds of rotation of the Magnus rotors.

The invention also concerns a method of operating a ship, in particular a cargo ship, with at least two Magnus rotors, wherein at least one Magnus rotor is provided on the port side of the ship and at least one Magnus rotor is provided on the starboard side of the ship. The method has a step of detecting the direction of a wind. The method further has a step of operating the at least one Magnus rotor on the port side of the ship and the at least one Magnus rotor on the starboard side of the ship with the same direction of rotation so that the action between the wind and the at least two Magnus rotors provides for generating a force directed substantially in the direction of the forward direction or the rearward movement of the ship. In that case the speed of rotation of the at least one Magnus rotor on the port side of the ship is different from the speed of rotation of the at least one Magnus rotor on the starboard side of the ship.

That method is advantageous as in that way, in the case of a forward or rearward movement which is at least partially caused by the Magnus rotors, deflection of the ship can be effected only by or in supporting relationship by the Magnus rotors. Thus the deflection can be effected jointly with a rudder assembly in order to assist the latter, or also solely by the operating according to the invention of the Magnus rotors to completely relieve the load on the rudder assembly.

The invention also concerns a ship, in particular a cargo ship, comprising at least one Magnus rotor, a motor associated with the Magnus rotor and an associated converter. The ship further has a control unit for controlling the converter, the motor and therewith the Magnus rotor. The control unit in a first operating mode is adapted to operate the at least one Magnus rotor with a direction of rotation such that the action between the wind and the Magnus rotor provides for generating a force which is directed substantially in opposite relationship to a forward direction of the ship. The control unit in a second operating mode is adapted to operate a Magnus rotor on the port side of the ship with a first direction of rotation such that the action between the wind and the first Magnus rotor provides for generating a force directed substantially in the direction of the forward direction or the rearward movement of the ship. The control unit is further adapted to operate a second Magnus rotor on the starboard side of the ship with a second direction of rotation which is opposite to the first direction of rotation such that the action between the wind and the at least one second Magnus rotor provides for generating a force which is directed substantially in opposite relationship to the direction of the force of the at least one first Magnus rotor. The control unit in a third operating mode is adapted to operate a first Magnus rotor on the port side of the ship and a second Magnus rotor on the starboard side of the ship with the same direction of rotation such that the action between the wind and the first and second Magnus rotors provides for generating a force directed substantially in the direction of the forward direction or the rearward movement of the ship. The speed of rotation of the first Magnus rotor is different from the speed of rotation of the second Magnus rotor.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Embodiments by way of example and advantages of the invention are described more fully hereinafter with reference to the following Figures.

FIG. 1 shows a perspective view of a ship with four Magnus rotors,

FIG. 2 shows a block circuit diagram of a control of the ship with four Magnus rotors,

FIG. 3 shows a perspective view of a ship with four Magnus rotors,

FIG. 4 shows a diagrammatic plan view of the ship with four Magnus rotors,

FIG. 5 shows a diagrammatic plan view of the ship with four Magnus rotors for generating a forward propulsion force,

FIG. 6 shows a diagrammatic plan view of the ship with four Magnus rotors for generating a rearward propulsion force,

FIG. 7 shows a diagrammatic plan view of the ship with four Magnus rotors for generating a moment about the center of gravity of the ship,

FIG. 8 shows a diagrammatic plan view of the ship with four Magnus rotors for generating a forward propulsion force and a moment about the center of gravity of the ship.

FIG. 9 shows a diagrammatic cross-sectional view of a Magnus rotor according to the present invention,

FIG. 10 shows a diagrammatic plan view of a Magnus rotor of a ship with a rotor mounting,

FIG. 11 shows the view of FIG. 10 with a vector diagram,

FIG. 12 shows the views from FIGS. 10 and 11 with a vector diagram, and

FIG. 13 shows the view from FIG. 12 with an alternative vector diagram.

DETAILED DESCRIPTION

FIG. 1 shows a perspective view of a ship with four Magnus rotors 10. In this case the ship has a hull comprising an underwater region 16 and an above-water region 15. The ship further has four Magnus rotors 10 which are arranged at the four corners of the hull and which are preferably cylindrical. In this case the four Magnus rotors 10 represent wind-operated drives for the ship according to the invention. The ship has a bridge 30 arranged in the forecastle. The ship has underwater a screw 50 or a propeller 50 as well as a rudder assembly 60 or a rudder 60. For improved maneuverability the ship can also have transverse thruster rudders, wherein preferably one is provided at the stern and one to two transverse thruster rudders are provided at the bow (not shown). Preferably those transverse thruster rudders are driven electrically. In this case the bridge 30 and all superstructures above the weather deck 14 are of an aerodynamic configuration to reduce wind resistance. That is achieved in particular by sharp edges and sharp-edged structures being substantially avoided. To minimize wind resistance and achieve an aerodynamic configuration as few superstructures as possible are provided.

The ship has a longitudinal axis 3 arranged to extend parallel to the keel line and horizontally. Thus when travelling straight ahead (and without the operation of transverse thruster rudders) the longitudinal axis 3 corresponds to the direction of travel of the ship.

FIG. 2 shows a block circuit diagram of a control of the ship with four Magnus rotors. Each of the four Magnus rotors 10 has its own motor M and a separate converter U. The converters U are connected to a central control unit SE.

A diesel drive DA is connected to a generator G to generate electrical energy. In that respect, instead of a diesel drive DA, it is possible to provide an array of a plurality of individual diesel drives DA with the generator G or a corresponding number of individual generators G which considered as a whole respectively provide to the exterior the same power as a corresponding individual large diesel drive DA or generator G. The respective converters U are connected to the generator G. The Figure also shows a main drive HA also connected to an electric motor M which in turn is connected with a separate frequency converter U both to the control unit SE and also to the generator G. In this case the four Magnus rotors 10 can be controlled both individually and also independently of each other.

Control of the Magnus rotors 10 and the main drive HA is effected by the control unit SE which, from the current wind measurements (wind speed, wind direction) E1, E2 and on the basis of the items of information relating to the target and actual travel speed E3 (and optionally on the basis of items of navigation information from a navigation unit NE), determines the appropriate speed of rotation and direction of rotation for the individual Magnus rotors 10 and the main drive HA to achieve a desired forward propulsion force. In dependence on the thrust force of the four Magnus rotors 10 and the current speed of the ship and the target value of speed, the control unit SE steplessly regulates the main drive HA in a downward direction if that is necessary. Thus the wind energy power can be automatically and directly converted into a fuel saving. The ship can be controlled even without the main drive HA, by means of the independent control of the Magnus rotors 10. In particular stabilization of the ship can be achieved in a heavy swell, by suitable control of the respective Magnus rotors 10.

In addition it is possible to provide one or more transverse thruster rudders QSA to improve maneuverability of the ship. In that respect a transverse thruster rudder QSA can be arranged at the stern and one to two transverse thruster rudders QSA can be provided on the ship at the front. A motor M for the drive and a converter U are associated with each transverse rudder QSA. The converter U is in turn connected to the central control unit SE and the generator G. Thus the transverse thruster rudders (only one is shown in FIG. 2) can also be used for controlling the ship as they are connected to the central control unit SE (by way of the converter U). The transverse thruster rudders QSA can each be actuated individually in respect of their rotary speed and direction of rotation, by the central control unit SE. Control can be effected in that respect as described above.

FIG. 3 shows a perspective detail view of the ship with four Magnus rotors 10. The Figure shows the control of an individual one of the four Magnus rotors 10. In this respect, the Figure shows the control unit SE for actuation of the diesel drive DA, the generator G and the converter U of the one Magnus rotor 10. The diesel drive DA serves to drive the generator G which then in turn generates electrical energy and feeds it inter alia into the illustrated converter U. In accordance with its actuation the converter U feeds that electrical energy through the control unit SE to the motor M to operate it in respect of direction of rotation and rotary speed in accordance with the settings of the control unit SE. In that case the generator G can also feed its electrical energy to further consumers like the converters U of the further three Magnus rotors 10 in FIG. 1 or also to the on-board network or transverse thruster rudders and the like. The converter U can also receive electrical energy from other sources.

The control unit SE is connected to an operating unit BE which can be arranged for example on the bridge of the ship. By way of that operating unit BE, inputs can be actuated to the control unit SE by the crew of the ship. The operating unit BE can have input options such as a keyboard or a touch screen display. There can also be knobs for pressing or turning, keys, switches, levers or the like as the input means. They can be physically defined and/or can be virtually displayed for example on a touch screen display. It is also possible to implement inputs to the control unit SE by means of speech input, for example by way of a microphone. In addition items of information and messages of the control unit SE can also be displayed and outputted by means of the operating unit BE, for example optically on display elements such as displays or monitors, acoustically by way of loudspeakers etc, in the form of signal or warning sounds or a spoken message or also by means of a printer or plotter in the form of a printout on paper or the like.

FIG. 4 shows a diagrammatic plan view of the ship with four Magnus rotors 10a, 10b, 10c and 10d. In this case the four Magnus rotors 10 in FIG. 1 as shown as Magnus rotors 10a, 10b, 10c and 10d. The Magnus rotors 10a, 10b, 10c and 10d are each driven by the four respective motors Ma, Mb, Mc and Md which in turn are respectively fed and actuated by the four converters Ua, Ub, Uc and Ud. The four converters Ua, Ub, Uc and Ud are actuated by the control unit SE which receives its inputs by way of the operating unit BE. In that respect the positions of the motors Ma, Mb, Mc and Md and converters Ua, Ub, Uc and Ud, shown in FIG. 4, do not have to correspond to the real arrangement as this diagrammatic plan view is only intended to illustrate the interrelationship in principle of the control of the Magnus rotors 10a, 10b, 10c and 10d.

According to the invention therefore the Magnus rotors 10a, 10b, 10c, and 10d can each be actuated individually by the control unit SE by means of the converters Ua, Ub, Uc and Ud. It is thus possible to give each Magnus rotor 10a, 10b, 10c and 10d, its own rotary speed and its own direction of rotation out of two possible directions of rotation. In that respect, those presettings can be implemented on the one hand by the operating unit BE, that is to say settings for each individual one of the four Magnus rotors 10a, 10b, 10c and 10d can be actuated directly by way of the operating unit BE, and those settings can then be converted by the control unit SE into corresponding control signals for the converters Ua, Ub, Uc and Ud. On the other hand, the operating units BE can also predetermine modes of operation of the ship, which are then further processed by the control unit in order to actuate each individual Magnus rotor 10a, 10b, 10c and 10d in such a way that the co-operation of all four Magnus rotors 10a, 10b, 10c and 10d provides the predetermined operating mode for the ship.

The possible options arising out of that individual actuation of the four Magnus rotors 10a, 10b, 10c and 10d for the ship according to the invention will be illustrated hereinafter.

FIG. 5 shows a diagrammatic plan view of the ship with four Magnus rotors 10a, 10b, 10c and 10d for generating a forward propulsion force. To improve clarity of the drawing this view shows the four Magnus rotor 10a, 10b, 10c and 10d without the motors Ma, Mb, Mc and Md, the converters Ua, Ub, Uc and Ud, the control unit SE and the operating unit BE in FIG. 4. In this view, a wind W acts from the left, that is to say from port, on the ship or the Magnus rotors 10a, 10b, 10c and 10d. To generate a forward propulsion force using the Magnus effect the Magnus rotors 10a, 10b, 10c and 10d are therefore actuated by the control SE in such a way that they rotate to the right, that is to say clockwise. In order moreover to generate the same respective forward propulsion force by each of the four Magnus rotors 10a, 10b, 10c and 10d they are also operated at the same speed of revolution. In that respect, for the sake of simplification, it is assumed that the wind speed is matched to the speed of revolution of the Magnus rotors 10a, 10b, 10c and 10d, that is to say it is assumed to be the same for all four Magnus rotors 10a, 10b, 10c and 10d. Nonetheless it is however also possible to determine a specific wind speed for each individual Magnus rotor 10a, 10b, 10c and 10d and to adapt the speed of revolution of each individual Magnus rotor 10a, 10b, 10c and 10d thereto in order to achieve the same forward propulsion for each individual Magnus rotor 10a, 10b, 10c and 10d.

When the Magnus rotors 10a, 10b, 10c and 10d are actuated in such a way that each of them generates the same forward propulsion force F_forwardthen the four forward propulsion forces F_forward,1, F_forward,2, F_forward,3and F_forward,4are added to give a total forward propulsion force F_{forward,total}of the ship, which the ship experiences by virtue of the Magnus rotors 10a, 10b, 10c and 10d. At the same time ideally there are no lateral forces or a moment about the center of gravity of the ship.

FIG. 6 shows a diagrammatic view of the ship with four Magnus rotors 10a, 10b, 10c and 10d for generating a rearward propulsion force. For that purpose the four Magnus rotors 10a, 10b, 10c and 10d, with the same wind conditions as assumed in FIG. 5, are actuated with the opposite direction of rotation as was used in FIG. 5 to generate the forward propulsion force. In the case shown in FIG. 6 of a wind W from port, that means that the four Magnus rotors 10a, 10b, 10c and 10d for generating a rearward propulsion force are driven in rotation towards the left, that is to say in the anti-clockwise direction. In that respect in this case also the four Magnus rotors 10a, 10b, 10c and 10d can be driven at different speeds of rotation in order in each case to achieve the same rearward propulsion force F_rearwardfor each Magnus rotor 10a, 10b, 10c and 10d. Those four individual rearward propulsion forces F_rearward,1, F_rearward,2, F_rearward,3and F_rearward,4are added to give a total rearward propulsion force F_{rearward,total}. At the same time ideally no lateral forces or a moment about the center of gravity of the ship occur.

That total rearward propulsion force F_{rearward,total}can be used on the one hand to drive the ship according to the invention in the rearward direction, just as the total forward propulsion force F_{forward,total}can drive the ship according to the invention in the forward direction. In that respect the respective total forward propulsion force F_{forward,total}or the total rearward propulsion force F_{rearward,total}of the four Magnus rotors 10a, 10b, 10c and 10d can be used alone to drive the ship accord ng to the invention, that is to say in the case of a pure total forward propulsion force F_{forward,total}or total rearward propulsion force F_{rearward,total}no lateral forces or moments occur and the ship travels in a straight line forwardly or rearwardly.

In that respect it is to be noted that, by virtue of the movement of the ship in the medium which is itself moving, namely water, flows and waves act at any time on the underwater region 16 of the ship and influence the direction of movement, that is to say the course of the ship, by way of those forces. Equally the wind W not only produces the Magnus effect but also acts on the above-water region 15 of the ship and thus also causes deflection of the ship from its desired direction of movement and displacement of the ship into the direction of the ship, in which the wind is blowing, that is to say towards leeward. Those sea and wind influences may have to be taken into consideration in navigation so that an ideal pure forward or rearward movement of the ship will only rarely occur, but rather the generated forward propulsion force F_{forward,total}, or total rearward propulsion force F_{rearward,total}of the four Magnus rotors 10a, 10b, 10c and 10d are superposed with the natural forces acting on the ship to produce a real forward or rearward movement thereof.

Furthermore, still further drives for the ship can additionally act both in the forward direction and in the rearward direction. Thus forward travel or rearward travel of the ship can be assisted by a forward propulsion force F_{forward,screw}or rearward propulsion force F_{rearward,screw}by a ship screw 50 or the like. In addition, in forward or rearward travel of the ship, lateral forces can also be produced, for example by transverse thruster rudders, to laterally deflect the ship. Likewise lateral forces can be exerted by way of the rudder assembly 60 to deflect the ship. All those forces are added to give a total forward or rearward movement of the ship.

In addition the total rearward propulsion force F_{rearward,total}of the four Magnus rotors 10a, 10b, 10c and 10d can also be used to brake a ship which is travelling forwardly in order on the one hand to reduce the forward travel or on the other hand to completely stop its forward travel. That situation can occur if the ship is travelling forwardly and then the total rearward propulsion force F_{rearward,total}the four Magnus rotors 10a, 10b, 10c and 10d is applied.

In that case the forward movement can be produced by the total forward propulsion force F_{forward,total}of the four Magnus rotors 10a, 10b, 10c and 10d and/or by the forward propulsion force F_{forward,screw}of a ship screw 50 or the like. If the forward movement of the ship is at least partially produced by the total forward propulsion force F_{forward,total}of the four Magnus rotors 10a, 10b, 10c and 10d, the four Magnus rotors 10a, 10b, 10c and 10d are to be reduced in their speed of revolution, down to a stopped condition. Then the direction of rotation is to be reversed and the speed of rotation is to be attained, which is intended to produce the total rearward propulsion force F_{rearward,total}by the four Magnus rotors 10a, 10b, 10c and 10d. In that respect, braking of the four Magnus rotors 10a, 10b, 10c and 10d and reversal thereof and acceleration in the opposite direction of rotation is coordinated as between the four Magnus rotors by the control unit SE in such a way that, at any moment in time, reversal of the total forward propulsion force F_{forward,total}to the total rearward propulsion force F_{rearward,total}causes as far as possible only forces in the forward or rearward direction respectively in order to avoid lateral forces and moments due to the four Magnus rotors 10a, 10b, 10c and 10d. If the ship is driven forwardly by other drive forces like the forward propulsion force F_{forward,screw}of a ship screw 50 or the like, that is to say the four Magnus rotors 10a, 10b, 10c and 10d are in a stopped condition, then, to initiate a braking action by means of the Magnus effect, they are to be accelerated in the appropriate direction of rotation to the required rotary speed, in the same way as described hereinbefore for the situation involving a reversal in the forces involved.

In that respect, braking of a ship is of particular significance as the ship moves floating in the medium water and does not have a solid surface therebeneath, like for example a motor vehicle, in relation to which a braking force can be applied. Thus, hitherto ships were decelerated by reversing the direction of rotation of the screw 50, thereby producing a force in the water, that is in opposition to the forward movement. That deceleration effect only acts very slowly because of the enormous inertia of the mostly very large ships, in particular cargo ships, so that braking of the ship already has to be initiated a long time before the moment at which the ship comes to a stop. As a result, a ship and in particular a cargo ship can scarcely perform a braking operation in order for example to avoid a collision with another ship or the like. Furthermore, generating a rearward force by the screw 50 to decelerate the ship in the water also leads to a lateral force which deflects the ship from its actual course and which has to be compensated by the rudder assembly 60. If deceleration is indeed performed with full rearward force by the screw 50, that lateral force can even become so great that it can no longer be compensated by the rudder assembly 60 and the ship runs off course.

It is therefore particularly advantageous to support deceleration of a ship by means of the four Magnus rotors 10a, 10b, 10c and 10d or to perform such deceleration solely thereby. It is possible in that way to generate a higher rearward propulsion force than only by the screw 50 alone so that it is precisely in a deceleration situation under full power to avoid a collision, that it is possible to achieve faster braking to a stopped condition. In addition, when performing braking solely by means of the Magnus rotors 10a, 10b, 10c and 10d, the laterally acting force due to the screw 50 can also be avoided and the ship can be held reliably on course by the rudder assembly 60 or the like, even when being decelerated.

FIG. 7 shows a diagrammatic plan view of the ship with four Magnus rotors 10a, 10b, 10c and 10d for generating a moment about the center of gravity of the ship. In that respect, it is assumed that the ship is being subjected to the same wind W acting from port, as in FIGS. 5 and 6. In this case the four Magnus rotors 10a, 10b, 10c and 10d are actuated by the control unit SE in such a way that the two Magnus rotors 10a and 10c rotate in such a way that they are added to give a total forward propulsion force F_{forward,total}and the two Magnus rotors 10b and 10d are rotating in such a way that they are added to give a total rearward propulsion force F_{rearward,total}. In the FIG. 7 situation that means that the two Magnus rotors 10a and 10c are rotating towards the right, that is to say in the clockwise direction, and the two Magnus rotors 10b and 10d are rotating towards the left, that is to say in the anti-clockwise direction.

Thus a total forward propulsion force F_{forward,total}is produced on the port side of the ship and a total rearward force F_{rearward,total}is produced on the starboard side of the ship, by the four Magnus rotors which are actuated in that way. As however the ship is designed as a whole, that is to say the two sides of the ship are joined together, that superimpositioning of the port-side total forward propulsion force F_{forward,total}and the starboard-side total rearward propulsion force F_{rearward,total}results in a rotary moment Mm about the center of gravity S of the ship. In that respect the four Magnus rotors 10a, 10b, 10c and 10d can be operated at the same speeds of revolution or also in part or respectively at different speeds.

In the FIG. 7 situation that moment Mm causes rotation of the ship about its center of gravity S towards the right, that is to say in the clockwise direction. Reversing the directions of rotation of all four Magnus rotors 10a, 10b, 10c and 10d however can also produce a moment Mm which acts in the opposite direction, that is to say towards the left, that is to say in the anti-clockwise direction.

That moment Mm can be used to rotate the ship on the spot in order thereby to maneuver the ship. A rotary moment Mm can be used in one direction of rotation to initiate rotation of the ship in that direction. In addition the opposite moment Mm can be used by reversal of the direction of rotation for braking the rotation of the ship. The same considerations apply in that respect as when decelerating the ship as shown in FIG. 6.

In that respect the four Magnus rotors 10a, 10b, 10c and 10d, for producing a pure rotary moment about the center of gravity of the ship, are to be actuated in such a way that, by virtue of their speeds of rotation, they respectively generate a force F_forward,1, F_rearward,2, F_forward,3and F_{rearward, 4}which are identical in magnitude, and the forces F _forward,1and F_forward,3differ from the forces F_rearward,2and F_rearward,4only in their sign, that is to say their orientation in the forward and rearward direction respectively of the ship.

FIG. 8 shows a diagrammatic plan view of the ship with four Magnus rotors 10a, 10b, 10c and 10d for generating a forward propulsion force and a moment about the center of gravity of the ship. Here the four Magnus rotors 10a, 10b, 10c and 10d are driven at different speeds of rotation in the same directions of rotation. In the FIG. 8 case a wind W is again acting on the ship from port. To produce a total forward propulsion force F_{forward,total}the four Magnus rotors are correspondingly driven towards the right, that is to say clockwise, see FIG. 5. In that respect however in the FIG. 8 case, the two Magnus rotors 10a and 10c at the port side of the ship are driven at a higher rotary speed than the two Magnus rotors 10b and 10d on the starboard side of the ship. In that way, a higher forward propulsion force is generated at the port side of the ship by the forces F_forward,1and F_forward,3than by the forces F _forward,2and F_forward,4at the starboard side of the ship. That excess of port-side forward propulsion force in relation to the starboard-side forward propulsion force generates a moment Mm about the center of gravity S of the ship, in this case a moment Mm which acts towards the right, that is to say clockwise, see FIG. 7. The total forward propulsion force F_{forward,total}and the moment Mm are superimposed to give an overall movement of the ship so that the ship is moved on the one hand forwardly and on the other hand at the same time towards the right.

Thus the different speeds of rotation of the four Magnus rotors 10a, 10b, 10c and 10d make it possible to also steer the ship when moving, that is to say to laterally influence the course, in the case shown in FIG. 8 to travel in the forward movement along a right-hand curve, that is to say a curve towards starboard, that is to say in the clockwise direction. If the speeds of rotation of the four Magnus rotors 10a, 10b, 10c and 10d are so selected that the two starboard-side Magnus rotors 10b and 10d generate higher forward propulsion forces F_forward,2and F_forward,4than the two port-side Magnus rotors 10a and 10c, the ship is deflected towards the left, that is to say towards port, that is to say in the anti-clockwise direction.

If the four Magnus rotors 10a, 10b, 10c and 10d are operated in such a way that a total rearward propulsion force F_{rearward,total}is generated, then in this case also the ship can be deflected in the manner shown in FIG. 8, that is to say also in the case of a rearward movement of the ship, whether that is for braking the ship or for the rearward movement of the ship, deflection of the ship can be effected by means of different rotary speeds of the starboard-side and port-side Magnus rotors 10a, 10b, 10c and 10d with the same directions of rotation.

In all those cases either the lateral deflection of the ship can be effected solely by the different rotary speeds of the starboard-side and port-side Magnus rotors 10a, 10b, 10c and 10d with the same directions of rotation, or such lateral deflection can also be effected jointly with the rudder assembly 60 or also by transverse thruster rudders in order to assist with the effects thereof.

In comparison with the production of a pure total forward propulsion force F_{forward,total}as described with reference to FIG. 5, the production of a combined total forward propulsion force F_{forward,total}with a moment Mm, in accordance with the description relating to FIG. 8, involves the production of a lesser total forward propulsion force F_{forward,total}as two of the four Magnus rotors 10a, 10b, 10c and 10d cannot be operated at full power, that is to say the maximum rotary speed, in order to produce the moment Mm required for deflection of the ship, by virtue of that difference in the rotary speeds and thus the starboard-side and port-side forward propulsion forces. Thus exerting a moment Mm for deflection of the ship always leads to a reduction in the total forward propulsion force F_{forward,total}.

In regard to the above-described possible ways of maneuvering center a ship with Magnus rotors, attention is to be drawn to the fact that four Magnus rotors 10a, 10b, 10c and 10d are admittedly shown in and described with reference to FIGS. 5 to 8, but those possible options are possible with a multiplicity of combinations of Magnus rotors as long as the rotary speed and direction of rotation can be predetermined as described hereinbefore at least for some of the Magnus rotors. In addition, for producing a moment Mm, as shown in FIGS. 7 and 8, it is at least necessary to have a respective Magnus rotor 10a, 10c on the port side of the ship and a Magnus rotor 10b, 10d on the starboard side.

FIG. 9 shows a sectional view of the Magnus rotor 10 according to the invention of a ship. The Magnus rotor 10 has a cylindrical rotor body 8 and an end plate 12 arranged in the upper region. The rotor body 8 is mounted rotatably on a rotor mounting 4 by means of a bearing 6. The rotor body 8 is connected by way of means for force transmission, to a drive motor 106, in the upper region of the mounting 4. The rotor mounting 4 has an inside surface 7. A measuring device 5 is arranged in the region of the inside wall 7, in a lower region of the rotor mounting 4. The measuring device 5 can be reached by means of a working platform 108.

The measuring device 5 is adapted to determine a flexural loading on the rotor mounting, as a consequence of a substantially radial force loading on the bearing 6, due to the action of a force on the rotor body 8. The measuring device has two strain gauge sensors 9, 11 which in the present example are arranged at an angle of 90° to each other.

The rotor mounting 4 is connected to the deck of the ship by means of a flange connection 110.

FIG. 10 shows a diagrammatic cross-sectional view through a Magnus rotor 10 according to the invention. The Magnus rotor 10 has the rotor mounting 4 within the rotor body 8. A first strain gauge sensor 9 and a second strain gauge sensor 11 are arranged at the inside surface 7 of the rotor mounting 4, as part of the measuring device. The first strain gauge sensor 9 is on a first axis 13, as viewed from the center point of the rotor mounting 4. The first axis 13 extends at an angle β relative to the longitudinal axis 3 of the ship. In a particularly preferred embodiment the angle β=0. The second strain gauge sensor 11 is arranged along a second axis 17 at the inside surface 7 of the rotor mounting 4, as considered from the center point of the rotor mounting 4. In a particularly preferred embodiment the angle between the first axis 13 and the second axis 17 α=90°.

The first strain gauge sensor 9 is connected by means of a signal line 19 to a data processing installation 423. The second strain gauge sensor 11 is connected by means of a second signal line 21 to the data processing installation 23. The data processing installation 23 is connected by means of a third signal line 25 to a display device 27. The display device 27 is adapted to display the direction and magnitude of the propulsion force acting on the rotor mounting 4. The data processing analysis is adapted to perform the method according to the invention.

FIGS. 11 to 13 show in principle the same view as FIG. 10, except that the diagrammatically indicated signal lines and the data processing installation as well as the display device have been omitted. The way in which the force acting on the Magnus rotor 10 is interpreted and determined by means of the measuring device is illustrated by means of FIGS. 11 to 13.

Beginning with FIG. 11 it is to be noted that the Magnus rotor 10 has a side remote from the wind and a side 34 towards the wind. The side 34 towards the wind has a surface, towards which wind flows in an afflux flow. The direction from which the wind flows to the Magnus rotor 10 in an afflux flow differs in that respect from the actual wind direction when considered stationarily, as the ship is generally in motion. Wind is incident on the Magnus rotor 10 in the direction of the arrow 33, whereby the Magnus rotor 10 is acted upon with a force, in the direction of the wind. That is referred to hereinafter as the wind force or briefly F_W. The Magnus rotor 10 rotates in the direction of the arrow 29. Because of the Magnus effect, that produces a force in the direction of the arrow 35, as shown in FIG. 12. That force is referred to hereinafter as the Magnus force or briefly F_M. The vector F_Mextends orthogonally relative to the vector F_W.

Therefore a force which is composed of the wind force F_Won the one hand and the Magnus force F_Mon the other hand acts on the rotor mounting 4. Addition of the two vectors F_Wand F_Mresults in a vector for the total force, hereinafter referred to as F_G. The vector F_Gis in the direction of the arrow 37.

FIG. 13 corresponds to FIGS. 11 and 12, and also FIG. 10, with the exception that the longitudinal axis 3 and the first axis 13 on which the first strain gauge sensor 9 is disposed coincide in FIG. 13. The total force F_Gin the direction of the arrow 37, which has already been deduced by reference to FIGS. 11 and 12, can be interpreted in the case of vectorial consideration as a sum of two vectors at a right angle to each other. In a particularly preferred embodiment the first strain gauge sensor 9 and the second strain gauge sensor 11 are arranged at a right angle to each other. In the FIG. 13 embodiment the first strain gauge sensor is arranged in the direction of travel and thus in the direction of the longitudinal axis 3 of the ship at the inside of the rotor mounting 4 while the second strain gauge sensor 11 is orthogonal thereto and is thus arranged substantially precisely in the transverse direction of the ship along the second axis 17.

Consequently the vector of the total force F_Gcan be divided into a vector in the direction of the longitudinal axis 3 or the first axis 13 and a second vector in the direction of the second axis 17. The proportion in the direction of the first axis 13 or the longitudinal axis 3 is referred to hereinafter as F_V. The vector in the direction of the second axis 17 is referred to hereinafter as F_Q. In that respect F_Vstands for propulsion force and extends in the direction of the arrow 39 while F_Qis to be interpreted as a transverse force and is in the direction of the arrow 41.

Depending on the direction in which the vector F_Gacts, the flexural loading detected by the first strain gauge sensor 9 differs from the flexural loading detected by the second strain gauge sensor 11. The ratio of the flexural loadings in the directions of the arrows 39 and 41 relative to each other changes with an angle γ between the total force F_Gin the direction of the arrow 37 and one of the two axes 13 and 17. For the situation where the flexural loadings detected by the first strain gauge sensor and the second strain gauge sensor 11 are of equal magnitude, the angle between the total force F_Gand the propulsion force F_Vγ=45°. For the situation where for example the flexural loading detected by the first strain gauge sensor 9 is twice as great as that detected by the second strain gauge sensor 11, the angle of F_Gto F_Vor relative to the first axis 13, γ=30°.

In general terms consequently the angle y between F_Gand F_Vfollows from the relationship γ=arc tan (signal value of the first strain gauge sensor 11/signal value of the second strain gauge sensor 9).

Likewise, taking the two signal values ascertained by the individual strain gauge sensors 9, 11, in addition to the angle of the acting force F_G, it is possible to ascertain therefrom the magnitude thereof in relation to selectively the first or second strain gauge sensor measurement value. The magnitude of the vector is afforded by the relationship F_G=F_V/cos(γ) or signal value equivalent=(signal value of the first strain gauge sensor 9)/cos y).

The various embodiments described above can be combined to provide further embodiments. All of the U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet are incorporated herein by reference, in their entirety. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments.

These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.

METHOD FOR OPERATING A SHIP, IN PARTICULAR A CARGO SHIP, WITH AT LEAST ONE MAGNUS ROTOR

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