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(11) | EP 2 029 425 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
A METHOD FOR WAVE PROPULSION OF WATERCRAFTS VERFAHREN EINES WELLENARTIGEN ANTREIBENS VON SCHWIMMENDEN EINHEITEN UNE MÉTHODE POUR PROPULSER UNE EMBARCATION PAR VAGUES |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
[0001] The object of the invention is a method for wave propulsion of watercrafts, surface or underwater ones.
[0002] Currently a number of devices use wave propellers for propelling watercraft, in which liquids are mixed perpendicular to the plane of the elements' oscillation.
[0003] Wave propulsion in known watercrafts is generated by putting into self-aligning or reciprocating motion, in the plane perpendicular to the liquid flow direction, a specific number of arms, to which, at a part of their length projecting from the hull of the watercraft, a surface propeller is attached. In most known solutions, presented for example in patent specifications US 3620651, US 5611666, RU 2009958 and ES 2170004, the arms are moved only with the possibility to change frequency while maintaining a constant amplitude of motion. Hydrodynamic efficiency of propulsion with the locomotor wave or constant amplitude is significantly undervalued in the conditions of change in the desired speed of the watercraft mainly due to swirls in the flow occurring along the surface propeller.
[0004] From patent specification EP 0903288, which represents the prior art closest to the subject-matter of independent claim 1, a solution of a watercraft with a wave propulsion is also known, in which each of the arms performing motion in the plane perpendicular to the liquid flow direction is driven by an individual generator of variable amplitude and frequency of movements, which are controlled by a central electronic control unit. The specification does not disclose a method for controlling the parameters of initiated locomotor wave in order to increase hydrodynamic efficiency of propulsion at different speeds of the watercraft.
[0005] A method for generating flow motion of watercraft referred to in the present invention uses, similarly to aforesaid solutions, motion generation in the plane perpendicular to the direction of fluid flow, generating motion of a certain number of arms, which at a part of their lengths project from the hull of the craft, and to which the surface propeller is attached. The essence of the invention consists in that the arms generate locomotor wave of variable characteristic, wherein the values of neighbouring amplitudes of the locomotor wave at a given moment are not constant but increase with the distance from the head of the system towards its centre so that the ratio between the currently neighbouring amplitudes ranges from 1 to 2.
[0006] Advantageously, an outline of the contour of the surface of the propeller is curve-shaped when the arms are arranged in the same plane, and the outline of the contour is symmetrical to the symmetry axis of the propeller.
[0007] The solution according to the present invention forces the wave flow of fluid, which in combination with a system of independently movable, self-aligning or reciprocating elements constituting a single and flexible set of structural elements, enables generation of the locomotor wave. The parameters of the wave, i.e. amplitudes or particular arms peaks and operational frequency, may be modified as a function of the fluid flow velocity lengthways the propeller, in real time, in a constant and independent manner. The result of controlling the wave characteristics and specific geometry of the propeller is security of the laminar flow of fluid along its surface and ensuring optimum parameters of the locomotor wave, resulting from the mechanics of a given fluid, wherein the parameters comply with the required fluid flow velocity after the surface propeller is properly immersed in the fluid, which hence ensures improvement of the hydrodynamic efficiency rate.
[0008] A method according to the invention is explained on the basis of a description of how a sample watercraft (shown in the figure) solution works and what its structure is. Figure 1 - a perspective projection of a single propelling device; figure 2 - one of the methods for the layout of two surface propellers in watercraft; figure 3 - geometry of the locomotor curve at a moment of accelerating the watercraft from zero velocity; figure 4 - geometry of the curve at the moment when the watercraft reaches an average progressive velocity; figure 5 - geometry of the locomotor curve at the moment when the watercraft reaches its maximum progressive velocity; figure 6 - contour of the surface propeller in the horizontal projection; figure 7 - possible configuration options for the propeller of a single and double hull watercraft and submarine.
[0009] A method of controlling the propulsion was shown based on the propelling system with the self-aligning arms, as shown in figure 1. In the option shown, the surface propeller (1) is a flexible rubber membrane connecting particular arms (2). The water is relocated perpendicular to the plane of arms (2) oscillation. Hydraulic bilateral actuators were used as motion generators (3). Each generator (3) is connected with two independent distributors (7). The system is equipped in the overflow tank (6) and the constant discharge pump (8), which delivers the working agent parallel to all generators (3). Change in the characteristics of the locomotor waves, which is shown nationally in figures 3, 4, and 5, is obtained by means of changing the opening time of distributors (7) valves, controlled by the electronic central control unit (4). The software controlling the operation of distributors ensures selection of wave characteristics depending on the velocity of the watercraft required by the operator as well as the current velocity of the watercraft. If velocity of the watercraft increases from zero, i.e. when the watercraft starts moving, wave amplitudes (A) are relatively high and operational frequency of the system is low, as shown in figure 3. When progressive velocity increases, amplitudes (A) of the motion of particular arms (2) decrease and frequency of the entire system increases, which is shown in figure 4, until it reaches the maximum value, as shown in figure 5, when operational frequency reaches its maximum value. The values of neighbouring amplitudes (A) of the locomotor wave at a given moment are not constant but they increase with the distance from the head of the system towards its centre, and shown in figures 3, 4 and 5. Symbol VC refers to relative liquid flow velocity, and symbol Vp refers to an absolute progressive velocity of the watercraft.
1. A method for wave propulsion of watercrafts, which consists in that a specific number
of arms (2) are put into motion in the plane perpendicular to the liquid flow direction,
and the arms at a certain part of their length project from the hull of the watercraft,
and to which a surface propeller (1) is attached, wherein each of the arms (2) performing
a self-aligning or reciprocating motion is propelled with an individual generator
(3) of variable amplitude (A) and frequency (f) of displacements, controlled by a
central electronic control unit (4), characterised in that the arms (2) generate a locomotor wave of variable characteristic, wherein the values
of neighbouring amplitudes (A1, A2 ; A2,A3 ; ...) of the locomotor wave at a given moment are not constant but increase with
the distance from the head of the system towards its centre so that the ratio (s)
between the currently neighbouring amplitudes (A2/A1 ; A3/A2 ; ...) of the wave ranging from 1 to 2.
2. A method according to claim 1, characterised in that the outline of the contour (5) of the surface of the propeller (1) is curve-shaped
when the arms (2) are arranged in the same plane.
3. A method according to claim 2, characterised in that the outline of the contour (5) is symmetrical to the symmetry axis of the propeller
(1).
1. Verfahren eines wellenartigen Antreibens von schwimmenden Einheiten, in dem eine bestimmte
Anzahl von Armen (2) in zur Flüssigkeitsströmungsrichtung senkrechten Ebene in Bewegung
gesetzt werden, wobei die Arme (2) auf einem Teil ihrer aus dem Rumpf der schwimmenden
Einheit herausragenden Länge ein flächiges Druckelement (1) besitzen, wobei jeder
der Arme (2) mittels eines individuellen Generators (3) in eine Schwenk- oder Hin-und-Her-Bewegung
mit einer variablen Verlagerungsamplitude (A) und -Frequenz (f) gesetzt werden, und
die von einer zentralen elektronischen Steuereinheit (4) geführt werden, dadurch gekennzeichnet, dass die Arme (2) eine verkehrsmotorische Welle mit einer variablen Kennlinie generieren,
wobei die Werte der benachbarten Amplituden (A1, A2, A2, A3;...) der verkehrsmotorischen Welle im jeweiligen Moment nicht konstant sind, sondern
sich mit dem Abstand vom Systemkopfstück in Richtung dessen Mitte vergrößern, und
das Verhältnis (s) zwischen den jeweils benachbarten Amplituden (A2/A1; A3/A2;....) im Bereich von 1 bis 2 liegt.
2. Verfahren nach Anspruch 1 dadurch gekennzeichnet, dass die Konturumrisse (5) der Fläche des Druckelements (1), wenn die Arme (2) in derselben
Ebene liegen, die Form einer Kurve haben.
3. Verfahren nach Anspruch 2 dadurch gekennzeichnet, dass die Konturumrisse (5) symmetrisch zur Symmetrieachse (9) des Druckelements (1) sind.
1. Une méthode pour propulser une embarcation avec des vagues, qui consiste en ce qu'un
certain nombre de bras (2) sont mis en mouvement dans le plan perpendiculaire à la
direction d'écoulement de liquide, et les bras, à une certaine partie de leur longueur,
font saillie de la coque de l'embarcation, et à laquelle une hélice de surface (1)
est attachée, dans laquelle chacun des bras (2) effectuant un mouvement d'auto-alignement
ou un mouvement alternatif est propulsé par un générateur individuel (3) variable
en amplitude (A) et fréquence (f) des déplacements, contrôlé par une unité de commande
électronique centrale (4), caractérisée en ce que les bras (2) génèrent une vague locomotrice de caractéristique variable, dans laquelle
les valeurs des amplitudes voisines (Ai, A2 ; A2,A3; ...) de la vague locomotrice
à un moment donné ne sont pas constantes, mais augmentent avec la distance de la tête
du système vers son centre de sorte que le(s) rapport(s) entre les amplitudes actuellement
voisines (A2/A1; A3/A2 ;..) de la vague varie(nt) de 1 à 2.
2. Une méthode selon la revendication 1, caractérisée en ce que le contour (5) de la surface de l'hélice (1) est en forme de courbe quand les bras
(2) sont disposés dans le même plan.
3. Une méthode selon la revendication 2, caractérisée en ce que le contour (5) est symétrique par rapport à l'axe de symétrie de l'hélice (1).
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.
Patent documents cited in the description