DE2529759A1 - DEVICE FOR GENERATING ENERGY FROM SEA WAVES - Google Patents

Description

Dr. F. Zumstein Sr. - Dr. E. Assmann - Dr. R. Koenigsberger Dipl.-Phys. R. Holzbauer - Dipl.-Ing. F. Klingseisen - Dr. F. Zumstein jun.

PATENT LAWYERS

TELEPHONE: COLLECTIVE NO. 225341

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CHECK ACCOUNT: MUNICH 91139-809. BLZ 7OO10O80 BANK ACCOUNT: BANKHAUS H. AUFHÄUSER

ACCOUNT NO. 397997. Bl-Z 70030600

8 MONKS 2.

BRÄUHAUSSTRASSE 4

6 / Li

74.2429

Kjell BUDAL, Trondheim and d
Johannes FALNES, Tronheim / Norway

Device for generating energy from ocean waves

The invention relates to a device for generating energy from ocean waves, with the aid of which the energy from ocean waves is converted into some other type of energy, so that usable energy is obtained. The device is either completely in the sea or can only be partially in the sea
immerse and contains at least one movable member, the
consists of a rigid or elastic material and vibrates under the influence of the waves of the sea. .The movable part or parts is or are connected to at least one damping resistor which

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supplies valuable energy and / or consumes energy.

The main task of the device is to supply energy, but the device as a whole or in some is Share can be used as a breakwater.

Various devices and devices have been proposed for utilizing the energy of the ocean waves, but they can obtained with the help of these proposed devices only small amounts of energy for certain purposes e.g. for operating billgen water pumps or signal buoys in the sea. Recently, however, the Energy generation from ocean waves is important on a large scale. In this context, reference is made to the journals "Nature", 249, p. 720 Ms? 24 (1974) and "IEEE Ocean", I, S, 240 to 243 (1974) referenced. These proposals relate to large-scale mechanical vibratory systems, the movable bairfceile which consist of concrete or other rigid building materials, which vibrate in the interaction of waves .Sys-fceis step over the moving parts. The moving parts operate pumps, which in turn operate a turbine that is connected to a 'Stroageneratoreinrichtung'

In US-PS 2,886,931 a hydraulic resonator is described » in which a liquid in a pipe or a chamber interacts directly with the sea and this is pressurized due to the wave motion. The vibrating column of liquid is used to generate energy, for example by the fact that the liquid, when it occupies its highest point, partially withdrawn into a basin mrd »that is above sea level, and that the liquid from the basin via a turbine back into the sea.

The basic frequency of a mechanical, oscillating system

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is (i / 27 () ~ fs / m, where S is the spring constant of the system and the total effective mass is designated by m. For certain waves, the power consumption or the power requirement S is mainly from buoyancy or in connection with The total mass also includes the additional hydrodynamic mass and possibly also the reshaped tuning mass, which will be discussed in more detail later.

As is well known, the deflection of an oscillating system has the greatest value when the fundamental frequency of the oscillating System is equal to the frequency of the exciting force. As is well known, this effect occurs when converting ocean wave energy with the help of fluids that are tuned to resonance, as is the case, for example, with the hydraulic Resonator described in US Pat. No. 2,886,951 is the case, but it is not heretofore known to use resonance tuning to be provided in the conversion of sea wave energy in a mechanical system that contains moving parts, which are set in vibration by the waves.

Known mechanical devices have a fundamental frequency which is much higher than the frequency range typical of ocean waves and which includes devices no means for setting or adjusting the fundamental frequency as a function of the wave frequency changes.

Hydraulic vibration systems that are tuned to resonance have several disadvantages when using such devices based on this principle, usable energy should be delivered. In particular, the loss due to fluid friction is very significant. Such a vibratory Device must be sized accordingly, and ultimately the tuning of the frequency is such Setting up an entire octave was problematic, however

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in the energy absorption of the natural waves in the most seas is very beneficial.

The difficulties in building a tuned mechanical vibratory device that must be overcome will be explained with reference to the device shown in Fig. 1 in the accompanying drawing. This device has a container 1 which executes vertical vibrations in the sea as a result of the action of the sea waves. The energy generation can for example be carried out with the help of a propeller 3, which is attached to the free end of a long shaft 2, the other End is connected to an electrical generator which is housed within the container 1. The fundamental period the vibratory device is approximately T = 2 7τΥΐ7έΓ »where with g the acceleration due to gravity and with 1 the Distance between the bottom of the container and the sea level is designated when the container is in the equilibrium position. Typical values for the period of oscillation in ocean waves are within the range from 7 to 14 seconds, and Preferably, such an interpretation is to be made that T can be freely selected within this range “I.e. that here 1 is adjustable within a range of 12 to 50 m. A correspondingly large-scale arrangement is over unsuitable for several reasons. In particular, the exciting force of the waves on the container is considerably reduced when the bottom of the container is well below sea level. This is due to the fact that the pressure fluctuations due of the wave movements decay, and that in the case of a sinusoidal wave exponentially with the distance from the sea level. For this reason, the container should be designed as low as possible. A deep container indicates large dead volume, since the oscillation amplitude of the container is significantly less than the height 1. With increasing Dimensions of the construction of such a device also take place the frictional forces with which the device is subject to.

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_ 5 -

The aim of the invention is to design a mechanical vibratory device that is tuned to resonance so that that wave energy can be converted into another form of energy with high efficiency. Preferably should The large, stimulating forces in the vicinity of the sea level are exploited, and in particular the structure should be justifiable Have dimensions. Preferably, the device should be designed so that with the help of a simply constructed Device, the fundamental frequency of the arrangement is adjustable, so that the device on the frequency changes of the waves in appeals to their characteristic area. In particular, according to the invention, a conversion of the mechanical vibration energy of the device into other forms of energy, in particular into Usable forms of energy take place with a high degree of efficiency.

According to a preferred embodiment of the invention, the Absorption of an energy in the case of irregular waves, namely above a value that which is tuned to resonance, can be optimally achieved, namely in that the vibratory movement using a motor or kit another drive mechanism can be controlled and regulated.

According to the invention, a device for generating energy is distinguished from ocean waves in that the vibratory device has a fundamental frequency, so that the with the help the energy absorbed by the device is as high as possible. With a stationary, sinusoidal or nearly sinusoidal wave means this is that the fundamental frequency is equal to or nearly equal to the wave frequency. With irregular waves, for example occur as a result of wind, this means that the basic frequency is equal to the annual average wave frequency, or that the basic frequency can be regulated to a value that is equal to or almost equal to the frequency that corresponds to the maximum, corresponds to the actual power spectrum of the waves, i.e. one such frequency, hereinafter referred to as the characteristic frequency

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is denoted by waves.

The component of the device that is exposed to the forces of the waves is and is thereby set in oscillation, is referred to below as an interaction element that has an or several masses are connected, which are referred to as so-called tuning masses, which are either within the device, lying in the sea, on the seabed or on land. These masses are not directly exposed to the influence of the forces of the waves, vibrate however in connection with the interacting member, so that the actual mass of the entire vibratable Arrangement is sufficiently sized so that the fundamental frequency of the arrangement is equal to or approximately equal to the characteristic Wave frequency is. The tuning mass preferably vibrates at a higher speed than the interaction element, so that the tuning mass is relatively small as a result, see above that the entire arrangement does not require too much space. In the case of a small mass, there is also the advantage that it can be applied to simpler ones Way in shape and / or size can be varied as a large mass, so that the fundamental frequency of the arrangement is simpler can be set or adjusted. The conversion of the kinetic energy of the mass into another form of energy, in particular into a usable form of energy is technologically easier to be carried out when there is a rapidly oscillating mass than in the case when the oscillating mass is slow swings.

The arrangement supplies usable energy, for example, by connecting the spacing lanes to an electrical generator that dampens the movement of the arm action member. The damping ability can be determined with the help of the damping resistance R, where the damping resistance is due to the power supplied to the generator, i.e. approximately the usable power, bestlBffit is »which has a time average of 1/2 Eu» where u is the velocity amplitude of the interaction term

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des is with sinusoidal motion. The interacting term is also dampened by the waves running out to the outside. The time average power for the generation of such waves is 1/2 R u, where R is the so-called output resistance which denotes a frequency-dependent, constant parameter with which every special device is afflicted is. If the usable power is to be 1 / 2Ru maximum, R = R is to be assumed, i.e. if the absorbed energy is equal to the output. This refers to sinusoidal waves. It is therefore important that the damping resistance R assumes a suitable value that the device operable as an effective wave energy absorber. In the case of waves occurring as a result of wind that are not exactly sinusoidal, the assumption can be made that the power consumed is maximum when R is somewhat larger than R, i.e. that the power consumed is slightly greater than the power delivered.

The operation of the resonance-tuned device is as follows: the incoming waves set the device in motion, whereby an outgoing wave occurs. If the vibratory arrangement is small compared to the wavelength, or if this is point-symmetrical, it is a circular wave. The outgoing wave is superimposed on the incoming wave Wave so that the wave obtained thereupon which passes the device has a reduced amplitude, and consequently a reduced energy. As a result, the device has absorbed energy from the shaft. The ability of the outgoing wave The more similar the time dependency of the outgoing wave to that of the incoming wave, the stronger the disturbance of the incoming wave Wave is. In the case of a linear oscillation system, the time dependence of the incoming wave can only be reproduced when the incoming wave is exactly sinusoidal. However, ocean waves are never sinusoidal, so the outgoing wave is is only almost similar to the incoming wave, and this departure

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The deviation is greater, the more the incoming wave deviates from the exact sinusoidal shape. What follows is a free, resonance-tuned, appropriately damped oscillatory arrangement extremely advantageous for absorption in sinusoidal Sea waves, however, the efficiency of such an arrangement drops considerably when waves occur due to wind.

The absorption in such a device can be improved in the following manner. If it is assumed that a force from a controllable motor or other controllable drive mechanism acts on the flywheel in addition to the inertia force, the restoring force (buoyancy force), damping force and the force supplied by the shaft are coordinated in such a way that the flywheel and thus the interaction element can be used in any way Way are movable. On the other hand, the flywheel can be replaced by a device combined from a drive motor and generator, which controls the movement of the changeover element. Assuming that the interacting member is acted upon by aem motor and the generator, this can move so that outgoing waves are generated with the same time dependence as the incoming waves, but the phase is reversed. Such an arrangement represents an optimal wave absorber for any type of wave, Ua. the arrangement supplies waves of any time dependency and consequently cancels the arbitrary time dependence of the waves. The energy absorption is reflected in the fact that the generator supplies more energy than the motor consumes. The difference corresponds to the usable energy,

With reference to the above, the present Invention a device for converting sea wave energy into any other form of energy and has -at least one movable part, the so-called interaction element, <ias consists of rigid or elastic material and is built into a damped Scüwicgungsanordming that

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contains at least one mass, at least one spring arrangement and at least one device for energy absorption, supplies the usable energy and / or consumes energy, whereby the interaction element interacts with the cells occurs, so that vibrational forces are absorbed from the shafts and the vibratory arrangement is set in vibration will. With such an arrangement, the object of the invention is achieved in that at least one other hater is provided, which is referred to as a so-called tuning mass, which is connected to the interaction element and itself added to the actual hatred of the entire vibratory arrangement, the tuning mass being arranged so that it is not directly influenced by the wave forces, but can oscillate in connection with the interaction element, so that the fundamental frequency of the arrangement is equal to or almost equal to the characteristic frequency of the ocean waves.

According to a preferred embodiment of the invention, a drive device such as a motor or a pump is provided, by the one variable force on the interaction element in addition to the other, on the interaction element exerted forces is exerted, wherein the drive means an oscillatory movement on the interaction member to the extent and in the time dependence that corresponds to that of the momentary excitation force of the wave, so that the energy released in the device is as large as possible.

Further details, advantages and features of the invention emerge from the following description of exemplary embodiments with reference to the accompanying drawing.

1 shows a schematic view of an arrangement which serves to explain the prior art;

2 to 7 show views of embodiments of a device according to the invention.

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Identical or similar parts are given the same reference symbols Mistake.

Referring to Figures 1 and 2, a semi-submerged container is in an equilibrium position. Of the Container 1 is held in this position with the help of a rope 2, a chain or the like, which is on rollers 3 and 4, the are accommodated in a housing 5 attached to the seabed, is guided and connected to a buoyant member 6 is. As a result of the buoyancy force of the link 6, the rope 2 is constantly subjected to a tensile force. The role 3 is with a Flywheel 7 connected, which in turn is connected to an electrical generator in a known manner. The generator as well as the mechanical and electrical connections are not shown in the drawing. The flywheel and the generator represent a common component of the device.

When the container 1 is exposed to the sea waves, it carries out alternating vertical movements (vibrations), so that the roller 3 and the flywheel 7 carry out vibrating rotary movements with the generator. With a corresponding, mutually coordinated choice of the influencing variables of the device, such as the inertial movement of the flywheel 7, the diameter of the roller 3 over which the rope 2 is guided, the oscillatable arrangement has a fundamental frequency that is close to the characteristic frequency of the waves is * In particular, the peripheral speed of the flywheel 7 is intended to be substantially greater than the linear speed of the container so that the mass flywheel dea may be relatively low. The electrical generator, which supplies the usable energy, is - preferably old - connected to the circumference of the flywheel 7, whereby the costs for such a generator decrease with increasing initial speed of the flywheel,

If the characteristic frequency of the waves changes, it should

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preferably the basic frequency of the vibratory Change the arrangement as well. This is achieved by changing the tuning mass. A flywheel is preferred for this, because the moment of inertia of a flywheel is easily adjustable is. On the other hand, the effective mass can be set by adjustment so that with the help of a corresponding Gear maintained the relationship between the linear movement of the rope 2 and the rotational movement of the flywheel can be.

The flywheel can also be acted upon by a force of a controllable or servomotor in addition to the other forces so that the arrangement, such as by the inertia forces, by the spring forces, damping forces due to the Buoyancy and forces transmitted by the waves in such a The interplay is that the container and the "mistake effect element" execute a movement that is exactly in sync with the incoming birds. Preferably that can Flywheel replaced by a motor generator that can be operated electrically, mechanically or hydraulically, such as E.g. a centrifugal pump, with the help of which the container movements can be regulated.

Figo 3 shows a modified embodiment of the in Fig.2 device shown, in which the roller-flywheel connection 3 to 7 carried out in two ways and in the container 1 is housed. Accordingly, the ropes 2 and the pulleys 4 are also duplicated, the pulleys 4 as above described, are attached to the seabed.

In Fig. 4 an arrangement is shown in which the rollers 3 are toothed and mesh with a rack 8, which is attached to a vibratable part 9, which via cables 10 is anchored to the seabed. When the container 1 vibrates, the toothed rollers 3 roll on the rods

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8 so that the flywheel 7 rotates.

In Fig. 5 there is shown an embodiment similar to that in Fig. 4 is similar, but the vibratory part 9 is constructed like a truss and denoted by 11 and on the Is attached to the seabed.

In the embodiments shown in FIGS. 2 to 5, there are transmission devices between the interaction member and the remaining part of the vibratory arrangement mechanically, for example with wire ropes or toothed wheels designed.

Hydraulic transmission devices can also be provided be.

The above embodiments are half-immersed.

With reference to FIGS. 6 and 7 vibratory devices are shown which interact with the waves which are completely immersed.

The arrangement according to the invention shown in FIG. 6, which is completely immersed, has containers 12 and 13 which are arranged in pairs and are filled with gas and which are connected to one another via a line 14. The container 12 has a movable or flexible wall 15 which represents the interaction element and which lies below sea level. The container 13 is provided with a rigid wall and can be arranged on land or also be submerged in water. This is preferably attached to the army base. Line 14 contains a turbine 16 which is connected to a generator as described above.

The movements of the container 12 under the influence of the waves

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set the wall 15 in vibration, so that the volume of the container 12 changes. Here, the gas flows through the line 14, which contains the turbine 16, so that it rotates. As in the embodiment shown in Fig. 2, the coordination of the arrangement by designing the turbine as a Motor pump done with a flywheel.

In this embodiment, part of the line can be ^{filled with E 1} liquid, which forms a vibrating column of liquid and at the same time represents all or part of the tuning mass of the arrangement. The vote can be set by the length or height of the liquid column.

In Fig. 7 a modified embodiment of the device shown in Fig. 6 is shown, wherein each of the containers and 13 is provided with a flexible wall 15. The two containers are arranged at a distance from one another which is approximately half the wavelength. As a result, the waves that impinge in the longitudinal direction of the conduit 14 generate one Opposite phase pressure in the two vessels so that the liquid or gas flow through the turbine 16 increases, which is housed in the line 14.

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Claims (1)

Claims SSwShT ΐΐΐ WV * iiU · »■■ · C ^ B C" · ■ "·> ϊϊ ^ ΪμΪ Zi ^ ta Ϊηη SCS «-« ■ ^ H Ϊημ ΐΐΖρ ■ *** Sk ** te * ΐ · »ΐΖιΖ * BW * Ϊβη ** ri * ϊ * ϊ * · SZw ΐΓΐ Device for generating energy from ocean waves, with at least one movable part as an interaction element, which consists of rigid or elastic material and is part of a damped, vibratory Arrangement represents the at least one mass, at least one spring mechanism and at least one energy-absorbing Contains device that supplies usable energy and / or consumes energy in which the interacting element interacts with the waves and absorbs the vibrational forces from the waves to the vibratory To set the arrangement in vibration, characterized by at least one more Mass as a tuning mass, which is connected to the interaction element and adds up to the total mass of the entire vibratory Arrangement added, the tuning mass being arranged so that it is not directly affected by the wave forces is applied, but oscillates in synchronism with the interaction element, and that the fundamental frequency of the oscillatable Arrangement is equal to or almost equal to the characteristic frequency of the ocean waves. 2. Device for generating energy from ocean waves with at least a movable part as an interaction element, which consists of rigid or elastic material and is a component represents a damped, oscillatable arrangement, the at least one mass, at least one spring device and contains at least one energy absorbing device which supplies usable energy and / or energy consumed, in which the interaction element "interacts" with the waves and vibrational forces from the Absorbs waves to the vibratory arrangement in 609884/0450 To set vibration, characterized by a drive device, preferably a motor or a pump that has a variable force on the interacting member in addition to the forces acting otherwise on the interaction member, wherein the drive device an oscillatory movement on the interaction element in terms of amount and time dependence that corresponds to that of the actually exerted wave force, with optimal energy being released. 3. device for generating energy from ocean waves with at least one movable part as an interaction element, which consists of rigid or elastic material and is part of a damped, vibratory arrangement represents the at least one mass, at least one spring device and at least one energy-absorbing Contains device that supplies usable energy and / or consumes energy in which the interacting element occurs in interaction with the waves and absorbs vibrational forces from the waves to the vibratory To set the arrangement in vibration, characterized by at least one tuning mass according to claim 1 and by a drive device according to claim 2. 4. Apparatus according to claim 1, characterized in that the vibratory arrangement has a damping that the time average value generated during the damping Power is approximately equal to the time average of the power, which vcn the interaction element in the form of an expiring Wave is delivered. 5. Device according to one of claims 1 or 3, characterized in that a translation device between the interaction element and the tuning mass provided 509884/0450 is, so that the tuning mass moves much faster than the interaction element. Device according to claim 1 and 3> characterized in that that the tuning mass contains at least one flywheel. 7. Device according to one of claims T, 2 or 3, characterized by an approximately stationary reference point as an energy transfer device between the interaction element and the remaining arrangement, wherein the interaction member with the reference point via a force-transmitting Device is connected, which is subjected to a tensile force to the extent that the force-transmitting device is under tension during the entire oscillation of the interaction element. 8. Device according to one of claims 1, 2 or 3, characterized in that the interaction member as a half-immersed, A buoyant body is designed that performs alternating, vertical movements in the sea. 9 «Device according to one of claims 1, 2 or 3, characterized characterized in that the interaction member is designed as a movable or flexible wall of a container, the swims in the sea. 10. Device according to one of claims 1, 2 or 3, characterized in that the interaction element is two with each other contains related moving parts or walls that are spaced apart, which is about half the characteristic wavelength of the waves. 509884/0450 Blank page