FR2522073A1 - Submerged power generator using water waves - has chambers with flexible domes and contg. liq. expelled by pressure of water acting down, to drive turbines - Google Patents

Abstract

The submerged generating unit includes a rigid enclosure mounted on pylons which support it at a fixed depth below the surface of the water. The enclosure is divided into a series of chambers each of which has a flexible dome covering it. The dome on each chamber is such that it may be deformed by the pressure of water under the crest of a wave. When a dome is deformed, water is expelled from the corresponding chamber via a system of non-return valves so that it passes two turbine blades situated one at either end of the unit. More than one such unit may be linked together, and they may be staggered in the direction of wave travel.

Description

Device to be kept submerged at shallow depth and intended to transform and harness wave energy
We have already thought for a long time to use the displacement of waves as a source of mechanical energy in order to transform it, in particular, into electricity.

 Among the known devices, there are some which include elastic capacities intended to be compressed and then released when the waves pass, which has the effect of creating a sort of pulsation with air held captive inside the device.

 It must be half submerged only so that between two crests of waves, in the hollows, the elastic capacities are at atmospheric pressure, that is to say at the minimum possible compression compared to the maximum which is caused by the crest of the wave.

 To be effective, such a device must imperatively be completely sealed in order to avoid the air outlet and the entry of water into the elastic capacities.

 The present invention relates to a device which also has elastic deformable parts but which must be completely submerged and which provides for an operation substantially different from that of the device described above.

 A device according to the invention must be kept submerged at shallow depth and is intended to transform and exploit the energy of the waves. I1 is of the type comprising on the one hand a rigid enclosure containing at least one turbine> or the like, and on the other hand flexible parts liable to deform under the effect of the pressure due to the weight of the concentrated water at l plumb with the crest of the waves, so that a fluid placed in the enclosure is pulsed in one direction, in a closed circuit, with a view to driving the turbine or turbines and is characterized in that the enclosure is divided into at least two aligned chambers which communicate in series by at least one passage provided with a non-return valve and which are each delimited by rigid walls and by a flexible upper dome, the downstream end chamber opening out opposite a turbine rotatably mounted at the inlet of a return channel, the outlet of which is located outside the upstream end chamber, where appropriate opposite a second turbine rotatably mounted, the turbine or turbines rotary being kinematically connected to PTOs of any content type located outside the enclosure.

According to other characteristics of the invention - The fluid is a liquid whose density is at
less equal to that of the water in which the device
must be kept submerged.

- The fluid has a density lower than that of water
in which the device must be kept submerged.

- The device comprises at least one rigid duct which
extends between two non-contiguous chambers in order to make them
communicate directly, the downstream end of this conduit
being advantageously located in the penultimate room
considering the upstream-downstream direction of the fluid flow.

- The device includes several rigid lon pipes
different hearts.

- The space in which the fluid must be located is provided with
partitions which channel said fluid when it is
moving.

- The device must be kept submerged obliquely, ex
downstream hopper being located higher than the upstream end.

- The non-return valve consists of a set of
partition delimiting the room considered, partition which is
articulated at its upper part and cooperates, in position
closing, with a fixed peripheral frame.

- The tops of the domes of the two end chambers are
distant by a distance greater than the maximum distance
who; can separate two peaks of successive waves.

- PTOs are linked to other
similar from another device shifts, compared to
previous, in the natural displacement direction of the waves.

- The device is placed next to another similar to a
distance small enough to favor a vertical flow of
surrounding water.

 The invention will be better understood from the detailed description below made with reference to the accompanying drawing. Of course, the description and the drawing are given only by way of an indicative and nonlimiting example.

 Figure 1 is a schematic sectional view showing a device according to the invention kept submerged at shallow depth.

 Figure 2 is a schematic view showing the pressure gradient exerted by a wave on a device according to the invention.

 Figures 3 to 5 are schematic views showing alternative embodiments of the non-return valves.

 Figure 6 is a schematic sectional view of a device according to the invention dipped obliquely.

 Figure 7 is a schematic plan view showing two devices according to the invention coupled and aligned.

 FIG. 8 schematically shows in plan four devices according to the invention coupled but offset in the direction of the natural displacement of the waves.

 Figure 9 is a front view of two devices according to the invention placed relatively close to each other.

 Referring to FIG. 1, it can be seen that a device according to the invention comprises on the one hand a rigid enclosure 1 containing two turbines with horizontal axis 2 and 3 and on the other hand flexible parts 4a, 4b, 4c and 4d liable to deform under the effect of the pressure due to the weight of the water concentrated below the ridge A of the waves.

 The enclosure 1 is divided into four chambers respectively la, lb, ic and id which are aligned and which communicate in serine, by a passage respectively 5, 6, 7 and 8 formed in the transverse partitions which determine the chambers, these passages being each provided with a non-return valve 9, 10, 11 and 12 respectively.

 Thus each chamber 1a, 1b, 1c and 1d is delimited by rigid walls and by a flexible upper dome.

 The end chamber ld (called "downstream" -due to the direction of flow of the liquid, as described below) opens opposite the turbine 2 mounted rotationally at the inlet of return channel 13 whose outlet 14 is located outside the other end chamber 1a (called "upstream") facing the second turbine 3.

 The turbines 2 and 3 are connected kinematically to power take-off members of any known type located outside the enclosure 1.

 The enclosure is kept submerged at a shallow depth by being subject to pylons 15-16 anchored in the underwater soil B.

 The entire inner part of the enclosure 1 is filled with a liquid whose density is at least equal to that of the water in which the device is kept immersed.

 This relatively heavy liquid constitutes a flywheel due to the large mass set in motion and, simultaneously, contributes to ballasting the enclosure which has all the more ground on the pylons 15-16 and on the ground B.

 When the waves move in the direction of the arrow F1, the crest A passes successively over the flexible domes 4a, 4b, 4c and 4d and this results in a difference in domes due to the mass of water which is pressure on these domes due to the mass of water which is greater below the ridge A.

 As a result, the flexible domes deform and are compressed (or "deflated"), which has the effect of greatly reducing the volume of the corresponding chamber and driving the liquid to the next chamber, in the upstream direction since the check valve prevents this liquid from flowing the other way.

 In FIG. 1, it can be seen that the dome 4a was compressed (fldegonfleal) and then resumed its original shape (plumped up) while the dome 4b is compressed and deformed owing to the fact that it is plumb with the crest A, the dome 4c undergoing a beginning of deformation.

 The staggered deformation in the direction of the arrow F1 (by series juxtaposition of the chambers 4a to 4d) makes it possible to exploit the energy due to the mass of the waves over a relatively large distance and which obviously depends on the length of enclosure 1 and the number of rooms it contains.

 We note that the horizontal displacement of the waves according to arrow F1 has the effect of deforming the domes 4 in the direction of their advancement clestv -dire that we exploit to the maximum the phenomenon of bugs, first by their weight and then by their displacement.

 The liquid contained inside the enclosure 1 therefore progresses from chamber 4a to chamber 4b, then from chamber 4b to chamber 4c and from chamber 4c to chamber 4d according to the arrows F2 that is that is, it is set in motion by the horizontal displacement of the waves.

 This liquid causes the turbine 2 to rotate in the direction of arrow F3 and returns via the channel 13 to the other end of the enclosure 1 where it sets the turbine 3 in motion, which constitutes the end of a cycle.

 There is always a flattened or "deflated" dome which is re-inflated, during the passage of the next wave, by emptying the corresponding chamber of the liquid contained in the adjoining upstream chamber. The dome 4a is "re-inflated" during filling of the chamber la by the liquid coming from the chamber ld, led by the channel 13.

 The inertia of the liquid must help maintain this movement even in the absence of waves but, in any case, the movement cannot unfortunately be reversed, thanks to the presence of the non-return valves 9, 10, 11 and 12 .

 As we know, behind the crest A of each wave is a slightly more pronounced trough compared to the average level located in front of the crest A and the displacement of this trough, correlative to that of the crest A , exerts on the domes a kind of suction which is exactly the opposite of the compression effect exerted by the crest A, so that the "inflation" of the domes is favored.

 We see that the principle according to the invention consists in exploiting both the vertical component and the horizontal component of the moving waves and we have schematized the effect exerted on a series of flexible domes, in FIG. 2, next to a wave.

 n sees that the domes 4a, b, c and d etc ... deform one after the other in the direction of arrow F6 which is the same as that of arrow F1.

 There is shown by a dotted line the pressure gradient which exerts its action on a device according to the invention and it can be seen that beyond a certain distance on either side of the crest For this purpose is zero, which was deliberately chosen when determining the immersion depth of the device, taking into account the flexibility of the dbmes.

 The effect of weight is concentrated below the ridge A for a short distance on either side of the theoretical summit of this ridge and we have shown this distance in C (Fig.l).

 We thus see that the rational length 1 of each dome must be at most equal to the distance C, which is determined experimentally and approximately.

 The number of rooms must be at least two to avoid pressure drops and absorb the full useful value of the wave in a room.

 In practice, the number of rooms is chosen to capture the maximum energy without giving the entire device excessive dimensions.

 An important parameter to take into account is the total length separating the vertices of the two end domes 4a and 4d. This must be greater than the wavelength, that is to say the distance which separates two peaks from two successive waves so that the enclosure always has at least one wave above it, being thus activated at all times.

 The non-return valves can be of any known type but it is of the greatest interest to choose an operating principle as robust and simple as possible to avoid operating irregularities due to corrosion of the water. sea or mechanical deformations for example.

 In Figure 1, these valves are shown schematically. In reality, we can use a known valve as seen on a larger scale in Figure 5, that is to say in the form of a very flexible flexible disc 20 which is integral with a small rod 21 connected to a transverse support 22 and located in the axis of the passage 23.

 During the passage of the liquid from right to left, the disc 20 deforms into a corolla according to the dotted trace n. It opposes the passage in the opposite direction because the pressure 1 'applies on the periphery of the passage 23.

 In Figure 3, we see that there is provided a ring 24 welded opposite the passage 25 and that on this ring 24 is securely fixed a sleeve 26 of very flexible material.

 When the liquid flows in the desired direction, it discards the sleeve 26, which is of slightly frustoconical shape.

according to arrows F7, and the liquid encounters no resistance because the passage section of the sleeve 26 is the same as that of the passage 25 and of the ring 24.

 If, on the contrary, the pressure of the fluid reverses, this pressure tends to deform the sleeve 26 downwards and, above all, to flatten it, which makes any passage of liquid in the opposite direction impossible.

 In FIG. 4, a system is provided comprising, facing the passage 27, a panel 28 of flexible material fixed above the passage 27 by means of members 29.

 The opening and closing of this valve are due to the deformation of the material which constitutes the panel 28.

 As indicated above, it is important that the length L which separates the vertices of the domes 4a and 4d (i.e. the axis of the end chambers la and ld), is at least equal to the wavelength so that there is always a pressure difference between these two end chambers la and ld.

 But, on a given site, the wavelength can vary in fairly large proportions so that in certain circumstances, and despite the precautions taken, there could occur cases where this difference in pressure would tend towards zero.

 To avoid this, a conduit 30 is provided (FIG. 1) which extends from upstream from the first chamber 1a to the penultimate chamber 1c.

 Thus a fraction of the moving liquid borrows this conduit 30 according to the arrows F8 instead of borrowing the wise steps 5, 6 and 7.

 This results in a certain loss of pressure, but this disadvantage is slight compared to the advantage that is obtained from the fact that any impediment to the operation of the system is impossible. Indeed, if two crests of waves are at the same time plumb with the two end chambers-la and ld, while the dome 4c is deflated, the flattening of the domes 4a and 4d will be hampered since the pressure on the dome sd keeps the valve 12 in the closed position and immobilizes the liquid in the intermediate chambers. Thanks to the conduit 30, the liquid contained upstream of the chamber la can flow directly towards the chamber lc, the dome 4c of which is in the deflated position at this time.

 In order for a device according to the invention to operate without fail in all the possible wavelength ranges at a given site, it no longer comprises a single conduit 30 but several conduits of different lengths.

 Thus, with reference to FIG. 7, there is seen a device according to the invention which comprises a channel 30 which extends from the chamber 1a to the interior of the chamber 1c and which is associated with another conduit rigid 31 which originates in the upstream chamber and which terminates beyond the chamber ld.

 Thus, the two chambers lc and ld receive the pressure of the liquid in return according to the arrows F8 and F9.

 In Figure 6, there is shown an embodiment according to which the chambers la, lb, lc and ld are separated from the return channel 13 only by a simple plate.

 However, according to one embodiment of the invention, the space in which the liquid must be located is provided with partitions which channel said liquid when the latter is in motion.

 Thus, in FIG. 1, it can be seen that the chambers 1a, 1b, 1c and 1b are separated from the return channel 13 by two parallel plates 43 and 44 joined at their ends by deflected curved turns 45 and 46 promoting the flow of the liquid to turbines 2 and 3.

 Between the plates 43 and 44, a space 47 is thus provided, this assembly constituting a volume which is deducted from the volume of the interior space of the enclosure 1 in which the liquid is located.

 In addition, these partitions, by promoting the flow of the liquid, ensure better operation of the assembly.

 As indicated above, the invention makes it possible to exploit the vertical component and the horizontal component of the force of the moving waves. To improve the efficiency of a device according to the invention, the whole of the enclosure is given 1 μm inclination which makes with the horizontal H an angle a, the downstream end being situated higher than the upstream end.

The device has a brake effect on the waves which results in a stronger thrust on the flexible domes, from which it results a more powerful force on the turbines 2 and 3
In this same FIG. 6, a particular embodiment of the non-return valves has been represented, according to which each of these valves is constituted by the assembly of a partition and not only by a valve situated opposite a passage. formed in such a partition, as shown in Figure 1.

 Here, the partitions 50, 51, 52 and 53 which delimit the chambers la, lb, lc and ld in the longitudinal direction oe the enclosure 1 are articulated at their upper part and cooperate, in the closed position, with a frame respectively 54 , 55, 56 and 57.

 The captive liquid placed inside the enclosure 1 can, for example, be sea water, which makes it possible to construct the entire device in a very simple manner without taking any particular precautions with regard to Being chéité, because a leak is then of no serious consequence, since there is no air.

 However, it is also not necessary that the seal is too poor since each passage with the outside creates a pressure loss detrimental to the good performance of the system.

 In FIG. 7, two devices have been shown placed side by side and aligned so as to be able to join by drive shafts 60 and 61 the power take-off members 62 and 63 corresponding respectively to the turbines 2 and to the turbines 3.

 We see in this figure that the bottom device itself has power take-off members 62 and 63 provided with transmission shafts 64 and 65 for another similar device, the invention making it possible to associate several speakers and to mount in parallel on the one hand all the turbines 2 and on the other hand all the turbines 3 in order to collect the movement of all the devices.

 By no longer using rigid and rectilinear transmission shafts 60, 61, 64 and 65 but other known transmission members such as so-called "Bowden" cables, cardan shafts, etc., it is possible to associate several offset devices the relative to each other, in the direction of the natural displacement of the waves.

 This is shown in Figure 8 where we see four speakers 1 offset from the ridges Al and A2 which move according to the arrows F1 towards the coast D.

 All the speakers are kept submerged as described above and their power take-off members are connected by members such as "Bowden" cables 70.

 These cables lead to an assembly 71 which captures their movement and transforms it to set in rotation, for example, a shaft 72 leading to an installation on the ground which may include, in particular, an alternator of any known type.

 Thanks to the combination of several offset speakers 1, it is possible to provide complete installations which are perfectly adapted to all sites, whatever their dimensions and their shapes, taking into account that the different speakers can not only be offset but can also not be parallel.

 In the event of a random wave regime, it is ensured that at least one of the speakers is always under the effect of a wave.

 The combination of several enclosures increases the overall inertia of the installation and maintains the movement of the different turbines, so that one is assured that the system is not always active, even in the time interval between two waves.

 It is possible to provide a kinematic connection between the two turbines 2 and 3 of the same enclosure with the aim, here again, of seeking to obtain a single overall mechanism providing great inertia of movement. In this case, there may be only one transmission output per enclosure.

 The axes of rotation of the turbines are advantageously provided with free wheels so that one or more stopped turbines do not brake those which are driving when they are themselves driven by the moving liquid.

 Between two neighboring enclosures, the space which separates them promotes a vertical flow of the surrounding water according to arrows F11 when this space is not too large.

 In accordance with the invention, this space is therefore chosen to favor such a flow, which has the advantage that a dynamic component is added to the weight component due to the mass of water in the waves.

 It is therefore preferable to provide two speakers of a given width rather than a single double width speaker, in order to take advantage of this phenomenon.

 According to an operating variant of a device according to the invention, a liquid lighter than water is used and the vertical effect directed from bottom to top (and no longer from top to bottom) is used, which manifests itself in the hollow of the waves (and no longer at the crest).

 It should be emphasized that the upstream chamber receiving the liquid from the downstream chamber ld, these two chambers must be equal. This is not necessarily the case for the median chambers which can be provided uneven, with the aim of voluntarily creating imbalances because they generate movements, which are the reason for the device.

 The invention is not limited only to the embodiments described and shown but on the contrary embraces all variants.

 In particular, the mechanical members used can be of a different type from those described: turbines with a vertical axis or with a horizontal axis, propellers, transmission members, etc. can easily be chosen by the skilled person depending on powers used, dimensions chosen, etc ...

 Likewise pylons 15 and 16 may prove to be useless in certain cases. The device is then directly fixed to the sea floor.

Claims (11)

1 - Device to be kept submerged at low depth  deur and intended to transform and exploit the energy of  waves, of the type comprising on the one hand a rigid enclosure  (1) containing at least one turbine or the like (2-3) and  on the other hand flexible parts (4) capable of being  deform under the effect of pressure due to the weight of  water concentrated below the crest (A) of the waves,  so that a fluid placed in the enclosure (1) is pulsed  in one direction, in a closed circuit, to train  the turbine (s) (2-3), characterized in that the enclosure  (1) is divided into at least two aligned chambers (the to  ld) which communicate in series by at least one passage (5,  6, 7 and 8) fitted with a non-return valve (9, 10, 11 and  12) and which are each delimited by rigid walls  and by a flexible upper dome (4a, 4b, 4c and 4d), the  downstream end chamber (ld) opening opposite a  turbine (2) rotatably mounted at the entrance of a re  tower (13) whose outlet (14) is located outside the  upstream end chamber weary if necessary n look of a  second rotary mounted turbine (3), the turbine or turbines  rotary (2-3) being kinematically connected to gold  PTOs of any known type (62-63)  located outside the enclosure (1).  tif must be kept submerged.  at least equal to that of the water in which the disposi  that the fluid is a liquid whose density is 2 ~ Device according to claim 1, characterized in that 3 - Device according to claim 1, characterized in that  that the fluid has a density lower than that  water in which the device is to be kept  immersed. 4 - Device according to claim 1, characterized in that  that it comprises at least one rigid conduit (30) which extends  stretches between two non-contiguous rooms in order to make them  communicate directly, the downstream end (30a) of this con  duit (30) being advantageously located in the penultimate  third chamber (1c) considering the upstream-downstream direction of  fluid flow  5 - Device according to claim 3, characterized in that  that it includes several rigid conduits (30, 31 and 32)  of different lengths.  of when it is in motion.  fitted with partitions (43-44-45-46) which channel said fluid  that the space in which the fluid must be located is  6 -Device according to claim 1, characterized in that  7 - Device according to claim 1, characterized in that  that it must be kept dipped obliquely, the end  downstream being located higher than the upstream end.  8 - Device according to claim 1, characterized in that  that the non-return valve consists of the assembly  a partition (50-51-52-53) delimiting the room consi  dereel partition (50-51-52-53) which is itself articulated  has its upper part and cooperates, in the closed position  turne, with a fixed peripheral frame (54-55-56-57).  9 - Device according to claim 1, characterized in that  that the vertices of the domes (4a and 4d) of the two chambers  dsextremite (la and ld) are distant by a distance (L)  greater than the maximum distance which can separate two  ridges (A) of successive waves. 10 - Device according to claim 1, characterized in that  that its power take-off members (62-63) are connected  to others similar to another device shifted, by  compared to the previous one in the direction of natural displacement  (F1) waves. 11 - Device according to claim 1, characterized in that  that it is placed next to another similar, to a dis  weak enough to favor a vertical flow of  surrounding water (F11).