tidal barrage

Abstract

A tidal barrage comprising a plurality of spaced apart towers, a plurality of barriers between the towers for controlling the flow of water through the barrage, and one or more turbine devices, wherein the towers comprise at least first, second and third towers, wherein the first tower is located between the second and third towers and houses one or more turbines, wherein one or more first barriers are disposed between the first and second towers and one or more second barriers are disposed between the first and third towers, wherein the barriers are configured such that when the one or more first barriers and the one or more second barriers are in a first configuration a first flow path through the barrage is defined from a first side of the barrage to a second side of the barrage and when the one or more first barriers and the one or more second barriers are in a second configuration a second flow path through the barrage is defined from the second side of the barrage to the first side of the barrage, and water flowing through the first and second flow paths flows in the same direction through the one or more turbines housed in the first tower, wherein the one or more barriers comprise a water-impermeable flexible membrane, a buoyancy member and one or more tethers.

Description

Technical Field

[0001] This disclosure relates to a tidal weir, and more particularly to a tidal weir capable of generating electricity from two bidirectional flowing phases using a unidirectional turbine generator. Background Technology

[0002] Traditional tidal weirs (or tidal range barriers) used for coastal protection, built on the same principles as gravity dams, are common, for example in the Netherlands. Like traditional dams, these weirs can also generate electricity, albeit less common, as tides flow over installed turbines. A notable example is the installation at the mouth of the Larancee River in France. However, some critics argue that such installations are uneconomical and environmentally harmful.

[0003] This disclosure relates to a highly portable, less complex, and less costly method that achieves the same purpose as conventional tidal range technology, but is significantly easier and less costly to install and maintain.

[0004] The purpose of this invention is to provide a simple, environmentally friendly, cost-effective, and inconspicuous tidal weir that has the potential for rapid installation, significantly reduces major marine civil engineering, and can be easily configured for power generation, flood mitigation, or coastal protection during full bidirectional or low tide operation, as well as providing recreational and transportation benefits. Summary of the Invention

[0005] According to a first aspect of the invention, a tidal weir is provided, comprising: a plurality of spaced-apart towers; a plurality of barriers between the towers for controlling water flow through the weir; and one or more turbine units; wherein the towers include at least a first tower, a second tower, and a third tower; wherein the first tower is located between the second tower and the third tower and houses one or more of the turbines; wherein one or more first barriers are disposed between the first tower and the second tower, and one or more second barriers are disposed between the first tower and the third tower; wherein the barriers are configured such that when the one or more first barriers and the one or more second barriers are in a first configuration, a first flow path through the weir is defined from a first side of the weir to a second side of the weir, and when the one or more first barriers and the one or more second barriers are in a second configuration, a second flow path through the weir is defined from the second side of the weir to the first side of the weir, and water flowing through the first flow path and the second flow path flows in the same direction through the one or more turbines housed in the first tower; wherein one or more of the barriers include an impermeable flexible membrane, a buoyancy member, and one or more tethers.

[0006] The one or more first barriers disposed between the first tower and the second tower preferably include a single bidirectional barrier, the single bidirectional barrier including an impermeable flexible membrane, a buoyancy member and one or more tethers.

[0007] By setting a bidirectional buoyancy barrier in the inlet channel defined between the first and second towers, passive control can be uniquely provided, wherein the barrier reverses direction in response to a change in flow direction without external control.

[0008] The one or more second barriers disposed between the first tower and the third tower preferably comprise a pair of unidirectional barriers. Each second barrier may include an impermeable flexible membrane, a buoyancy member, and one or more tethering chains.

[0009] Preferably, the tower further includes a fourth tower and one or more third barriers, the fourth tower being located on the opposite side of the third tower relative to the first tower, the one or more third barriers being disposed between the third tower and the fourth tower, wherein the third tower accommodates one or more additional turbine units, wherein the barriers are configured such that when the one or more third barriers are in a first configuration, a third flow path through the weir is defined from a first side of the weir to a second side of the weir, and when the one or more third barriers are in a second configuration, a fourth flow path through the weir is defined from a second side of the weir to a first side of the weir, and water flowing through the third flow path and the fourth flow path flows in the same direction through the one or more turbines housed in the third tower.

[0010] The one or more third barriers disposed between the first tower and the second tower preferably include a single bidirectional barrier, the single bidirectional barrier including an impermeable flexible membrane, a buoyancy member and one or more tethers.

[0011] When a pair of barriers are provided between the two towers, one of the barriers will be positioned on either side of the one or more turbines. When a single barrier is provided, the barrier can be moved between a first position on one side of the one or more turbines and a second position on the opposite side of the one or more turbines.

[0012] The tidal weir can be permanently applied to tidal estuaries, and can also be applied to tidal lagoons extending from the coastline or to independent enclosed areas located at sea, for purposes including but not limited to power generation, flood control and disaster reduction, creation of water sports and recreational facilities, or improvement of coastal erosion protection.

[0013] Where appropriate, the bridge structure can be supported on a tidal weir above a high water level marker to provide access for, but not limited to, maintenance, pedestrian or bicycle traffic, as well as rail and / or vehicle traffic and power transmission or cables (such as fiber optics).

[0014] In a plan view, the towers may be substantially rectangular or rhomboid in shape. The towers may be arranged in a straight or curved array, between which tidal flows are restricted and cannot bypass the array. The opposite faces of each pair of adjacent towers preferably have substantially parallel, flat, and smooth surfaces.

[0015] As discussed, one or more of the barriers include an impermeable flexible membrane, a buoyancy member, and one or more tethers. In use, the membrane may include a lower edge portion and an upper edge portion, the lower edge portion being fixed relative to the riverbed of the water body in which the weir is located, the membrane and the buoyancy member being attached to each other in the upper edge portion, and the tethers may include a first end and a second end, the first end being attached to the buoyancy member and / or to the membrane in the upper edge portion, and the second end being attached to an anchor.

[0016] The buoyancy component may include a manifold through which water can be introduced into the interior of the buoyancy component. The manifold may be connected to a pump.

[0017] The barrier including the buoyancy component is provided with buoyancy-assisted weirs, which, as further disclosed, can be deployed in different configurations to adapt to the function of tidal weirs for low tide or bidirectional flow power generation, and to adapt to any or all of the following further functions: including but not limited to flood control and disaster reduction, creating recreational facilities for water sports, or improving coastal erosion protection.

[0018] The towers can be made of any suitable material, including but not limited to prefabricated steel structures, stone structures, or cast-in-place concrete structures. The towers can be independent of each other, forming the weir by arranging a suitable array of towers and subsequently placing suitable barriers between the towers. These towers may include prefabricated submersible units, which can be arranged independently of each other as distinct components in appropriate locations before a cost-effective buoyancy weir is installed between them.

[0019] By housing turbines in towers spaced apart from each other and setting one or more barriers including buoyancy weirs between the towers, a cost-effective weir can be provided, with an installation cost that is only a fraction of any existing technology installation.

[0020] An array of unidirectional turbine units can be deployed across the lower part of the respective tower. The turbine units can be arranged substantially perpendicular to the direction of the tidal flow.

[0021] Each of the turbine units preferably includes a converging portion, a diffuser portion, at least a portion of a tube, and a turbine connectable to a generator. The converging portion is connected to a first end of a mixing chamber such that a venturi tube is defined between the end of the converging portion and the mixing chamber; the diffuser portion is connected to a second end of the mixing chamber, the diffuser being configured such that, in use, the pressure at the diffuser outlet is greater than the pressure at the venturi tube; at least a portion of the tube is located within the converging portion such that an annular structure is defined between the tube and the converging portion to form a first flow channel, and the tube defines a second flow channel within the tube; wherein the turbine is located within the tube.

[0022] Furthermore, preferred features are given in the dependent claims. Attached Figure Description

[0023] The invention will now be described by way of example with reference to the accompanying drawings:

[0024] Figure 1 A schematic plan view of the tidal weir according to the first arrangement in the low tide configuration is shown;

[0025] Figure 2 The reverse inward flow configuration is shown. Figure 1 The layout shown;

[0026] Figure 3 Showing a configuration in low tide Figure 1 A schematic plan view of one module of a tidal weir;

[0027] Figure 4 It shows the configuration in reverse flow. Figure 3 A schematic floor plan of the module;

[0028] Figure 5 An elevation view of the tidal weir dam supporting the bridge structure is shown;

[0029] Figure 6 It shows the applicable Figure 1 Plan and elevation views of the tower of the barrier shown;

[0030] Figure 7 It shows the applicable Figure 1 The plan and elevation views of the alternative tower for the tidal weir dam are shown, which includes optional installation auxiliary equipment;

[0031] Figure 8 It shows what is suitable for use as Figure 1 Side view of an exemplary buoyancy weir of a barrier in a tidal weir dam;

[0032] Figure 9It shows something similar to Figure 4 The diagram shows a schematic plan view of the module, but the module features an improved barrier arrangement;

[0033] Figure 10 It shows what is suitable for use as Figure 1 Side view of the bidirectional weir of the barrier in the tidal weir shown;

[0034] Figure 11 The deployed shapes of the membranes of exemplary unidirectional and bidirectional buoyancy weirs arranged in a straight line are shown; and

[0035] Figure 12 A trapezoidal tower arranged in a curved pattern is shown, which has the same characteristics as... Figure 11 Membranes of the same shape. Detailed Implementation

[0036] The invention will now be described by way of example with reference to the accompanying drawings.

[0037] Figure 1 and Figure 2 A schematic plan view of a tidal weir 1 arranged according to an exemplary configuration is shown, which is installed in a tidal body and is configured for both low tide and inward flow. Figure 3 and Figure 4 It shows Figure 1 and Figure 2 An ideal schematic plan view of a preferred power generation module of the barrier, also in a low tide and inward flow configuration.

[0038] In a broad sense, a tidal weir 1 includes multiple spaced towers 2, multiple barriers 3 between these towers for controlling the flow of water through the weir 1, and one or more turbine devices 4 (see Figure 6 The tower includes at least a first tower 2a, a second tower 2b, and a third tower 2c, wherein the first tower 2a is located between the second tower 2b and the third tower 2c and houses one or more turbine units 4. One or more first barriers 3a are disposed between the first tower 2a and the second tower 2b. One or more second barriers 3b are disposed between the first tower 2a and the third tower 2c. The barriers 3 are configured such that when one or more first barriers 3a and one or more second barriers 3b are in a first configuration (e.g., ...), Figure 1 and Figure 3 As shown), a first flow path is defined from the first side of the weir to the second side of the weir 1 (as indicated by the flow arrows), and when one or more first barriers 3a and one or more second barriers 3b are in a second configuration (as shown by the flow arrows), a first flow path is defined through the weir 1. Figure 2 and Figure 4As shown in the figure, a second flow path (as indicated by the flow arrows) is defined from the second side of the weir to the first side of the weir. This configuration, as clearly shown, causes water flowing through the first and second flow paths to flow in the same direction through one or more turbines housed in the first tower.

[0039] In this arrangement, preferably, the tower also includes a fourth tower 2d located on the opposite side of the third tower 2c relative to the first tower 2a, and one or more third barriers 3c disposed between the third tower 2c and the fourth tower 2d. The third tower 2c accommodates one or more additional turbine devices, wherein the barriers 3c are configured such that when one or more third barriers 3c are in a first configuration (e.g., Figure 1 and Figure 3 As shown), a third flow path (as indicated by the flow arrows) is defined from the first side of the weir to the second side of the weir, when one or more third barriers 3c are in the second configuration (as shown). Figure 2 and Figure 4 As shown in the figure, a fourth flow path (as indicated by the flow arrows) is defined from the second side of the weir to the first side of the weir. Similarly, as clearly shown in the figure, water flowing through the third and fourth flow paths flows in the same direction through one or more turbines housed in the third tower.

[0040] The first tower 2a and the third tower 2c, one or more turbine units 4 housed in the first tower 2a and the third tower 2c, and one or more first barriers 3a, second barriers 3b, and third barriers 3c between the first tower 2a and the third tower 2c can be considered to define the power generation module (e.g. Figure 3 and Figure 4 (Schematic depiction), wherein the weir preferably includes multiple power generation modules. As shown, one or more turbines 4 housed in the first tower 2a preferably face one or more turbines housed in the third tower 2c of the power generation module. Therefore, the water flow through the first tower 2a and the third tower 2c will meet in the area between the first tower and the third tower, and leave the weir between the first tower 2a and the third tower 2c, as... Figure 3 and Figure 4 As clearly shown.

[0041] like Figure 1 and Figure 2 As shown, the power generation modules can be arranged adjacent to each other. In this case, in the power generation module, the second tower 2b houses one or more turbines located away from the one or more turbines housed by the first tower 2a, and / or the fourth tower 2d houses one or more turbines located away from the one or more turbines housed by the third tower 2c.

[0042] A weir section can be installed along with this module, which omits the turbine device 4 and simply serves to block the water flow around the weir 1. This barrier section can employ any suitable structure. Furthermore, openings closed by one or more barriers 3 can be provided to allow vessels to pass through the weir. For example, as... Figure 1 and Figure 2 As shown, an opening 5 can be provided that allows two channels to pass through the barrier 3 during high tide. The barrier 3 is positioned during tidal formation so that it can be opened or removed to allow unobstructed passage for shipping.

[0043] Purely as a non-restrictive example, Figure 1 and Figure 2 The tidal dam shown includes five power generation modules and a navigation channel 5.

[0044] Figures 1 to 4 The barrier 3 is schematically shown and can take any suitable known form, including but not limited to, gates or caissons. However, preferably, the barrier 3 comprises a buoyancy barrier, as discussed in detail below. Regardless of their specific form, one or more of the first barriers 3a, one or more second barriers 3b, and one or more third barriers 3c may comprise a pair of barriers, one of which is disposed on either side of the one or more turbines. This is Figure 3 and Figure 4 The arrangement is shown in the diagram, where only functional barriers are illustrated. Optionally, one or more of the first barriers 3a, one or more second barriers 3b, and one or more third barriers 3c may comprise a single barrier that is movable between a first position on one side of the one or more turbines and a second position on the opposite side of the one or more turbines, for use in... Figure 3 and Figure 4 The flow is controlled appropriately in the manner shown.

[0045] The form of Tower 2 is not particularly limited. Preferably, Tower 2 extends along a longitudinal axis in the plan view, wherein the longitudinal axes are preferably arranged generally parallel to each other and / or generally aligned with the direction of the tidal flow. In this arrangement, as clearly shown in the figures, the longitudinal axes are all parallel and substantially aligned with the direction of the tidal flow. As shown, the tower can be substantially rectangular in the plan view. Again, as shown in the figures, adjacent towers can include opposing, parallel, substantially flat surfaces.

[0046] The flow axis of one or more turbine devices 4 is preferably arranged at an angle to the tidal flow. In this arrangement, the flow axis is preferably set substantially perpendicular to the longitudinal axis.

[0047] Figure 5 It shows Figure 1 and Figure 2 An elevation view of the tidal weir, where tower 2 has the additional optional function of serving as a bridge pier. An illustrative illustration shows how channel 5 can optionally be located in deeper water. Bridge 6 can be used for any of the purposes discussed above. As illustratively shown, the height of the bridge over the channel can be increased if necessary.

[0048] Now refer to Figure 6 and Figure 7 Consider the preferred turbine device and the exemplary structure of the tower in which the turbine device is installed.

[0049] Preferably, each turbine assembly 4 includes a converging portion 4a and a diffuser portion 4c. The converging portion 4a is connected to a first end of a mixing chamber 4b, such that a venturi tube is defined between the end of the converging portion 4a and the mixing chamber 4b. The diffuser portion 4c is connected to a second end of the mixing chamber 4b, and the diffuser 4c is configured such that, in use, the pressure at the diffuser outlet is greater than the pressure at the venturi tube. More preferably, at least a portion (not shown) of a tube located in the converging portion 4a defines an annular structure between the tube and the converging portion to form a first flow passage, and the tube defines a second flow passage within the tube, and a turbine connectable to a generator is located within the tube. This turbine assembly can be configured according to the teachings of patent EP 2864627, the contents of which are incorporated herein by reference in their entirety. However, it should be noted that the turbine assembly 4 can take any suitable alternative form.

[0050] The turbine units 4 are preferably arranged in an array, which can be configured as needed. For example, the turbine units 4 can be arranged in multiple rows, as shown in the figure. One or more turbine units 4 in any array may include turbine unit barriers (not shown) for selectively blocking water flow through the turbine units. For this purpose, any suitable barrier capable of blocking water flow can be provided.

[0051] Specific reference Figure 6The plan and elevation views show an exemplary tower comprising a group of turbine units 4, each configured according to the above discussion. A preferred embodiment is to integrally cast the converging section 4a and the diffuser section 4c into the tower. In another preferred embodiment, facilities for vertical wet recovery can be provided in the channel area above the waterline of the power generation section, which includes turbines and generators within a casing, as well as associated equipment including a mechanical power receiver. In this case, conventional gates or similar conventional devices can be installed across the turbine units upstream of the power generation section to prevent high flow rates through other turbine units in the same turbine unit group. Furthermore, if dry access to the casing of the power generation section is required, a second gate can be installed on the downstream side of the power generation section.

[0052] In a preferred embodiment, Tower 2 is manufactured off-site in a dry dock or other suitable location and is designed with substantially waterproof, submersible internal compartments, giving the entire tower buoyancy and allowing it to float to a position using conventional towing and back-towing tugs before being submerged, so as to lower it to a suitable location.

[0053] Figure 7 Optional additional installation auxiliary equipment is disclosed, which can be deployed integrally onto the tower. This installation auxiliary equipment may be omitted. When included, it can be used individually or in combination with each other, as will be apparent to those skilled in the art.

[0054] For example, one or more scour protection skirts 7 can be attached to the tower's base during off-site fabrication to facilitate rapid positional stability during installation. In some estuarine bed conditions, the tower's own weight can be used to achieve rapid partial penetration of the scour protection skirts 7 by allowing the tower to be submerged, increasing its self-weight, and thus providing temporary positional stability as it enters the estuarine bed.

[0055] In addition, vertical pile guide tubes 8 can be installed. These tubes can be open within the tower base, allowing piles to be driven into the estuary bed to secure the tower base in place. As will be readily understood by those skilled in the art, the number of piles to be driven into each tower will depend on several site-specific conditions, including but not limited to key environmental factors such as water depth, wave occurrence rate, estuary bed morphology, and pile size. Preferably, at least three piles will be driven into each tower, as they provide a convenient means of maintaining the tower base in a truly vertical position during installation.

[0056] Further penetration of the scour protection skirt 7 into the seabed can be achieved using conventional techniques. These techniques involve injecting water under the tower within the periphery of the scour protection skirt 7 via a suitable water injection conduit 9 at the base of the skirt 7, and pumping out the resulting slurry through selected components of a set of drainage conduits 10. With the water injection conduit 9 closed, this drainage pumping method can also be used alone to reduce the water pressure under the tower, effectively increasing the tower's self-weight and enabling further controlled penetration into the estuary bed. Installation can be initially accomplished by injecting grout into an annular structure between the interior of the vertical pile conduit 7 and the outer surface of the pile. Once the grout has solidified to secure the tower base to the pile, installation is then completed by injecting the grout under the tower base invert within the periphery of the scour protection skirt 7 via the water injection conduit until all water from this space is drained through the drainage conduit and undiluted grout begins to flow out through it.

[0057] Figure 7 A preferred embodiment is also disclosed in which each scour protection skirt 7 is separated to allow water to be pumped into one compartment via a selected water injection conduit 9 during installation, while water is pumped out of another compartment via a selected drain conduit 10, thereby selectively leveling the tower base. Figure 7 The example shown is only one of many possible configurations. Three compartments and three vertical pile guides allow the two plane axes of the tower base to be kept vertically tilted during installation. This process can also be assisted by selectively wedging one or more piles into the corresponding vertical pile guides to keep these points on the tower base vertically fixed while the height of one or more other points continues to be adjusted.

[0058] Figure 7 Another optional feature of the scour protection skirt is also disclosed, which can be used when an impermeable barrier has already been pre-installed at the same location on the estuarine bed. A cross-base gap 11 allows the tower base to be installed across the impermeable barrier without physical interference. A properly positioned water injection pipe 9 can be used to flush sand and silt out of the gap from the side, and then grout is injected through the same water injection pipe 9 to seal the gap to the impermeable barrier.

[0059] As described above, preferably, one or more barriers 3 include buoyancy barriers. Such buoyancy barriers can be arranged according to the disclosure in UK Patent Application No. 2102604.2, the contents of which are incorporated herein by reference. Preferably, Figure 3 and Figure 4 All barriers in the diagram are buoyancy barriers.

[0060] Figure 8An exemplary buoyancy barrier is shown, comprising an impermeable flexible membrane 12, a buoyancy member 13, and a tethering chain 14. Preferably, as shown, in use, the membrane 12 includes a lower edge portion 12a and an upper edge portion 12b, the lower edge portion 12a being fixed relative to the riverbed 15 of the water body 16 in which the weir 1 is located, the membrane 12 and the buoyancy member 13 being attached to each other in the upper edge portion 12b, and the tethering chain 14 including a first end 14b and a second end 14b, the first end 14b being attached to the buoyancy member 13 and / or to the membrane 12 in the upper edge portion 12b, and the second end 14b being attached to an anchor 17. Water levels are shown at 16a and 16b. An optional impermeable barrier is shown at 18. In some arrangements, the impermeable barrier 18 may also optionally serve as the anchor 17. For example, in an alternative arrangement, the lower edge portion 12a of the membrane may be located on the riverbed and subjected to ballast or otherwise secured.

[0061] The buoyancy component 13 preferably includes a manifold (not shown) through which water can be introduced into the interior of the buoyancy component 13. The manifold is preferably connected to a pump.

[0062] Buoyancy barriers offer a highly cost-effective solution. Furthermore, these buoyancy barriers can be raised and lowered as needed by introducing or discharging water from the buoyancy member 13. If necessary, a channel 21 or other device can be provided to receive the buoyancy member in its lowered position.

[0063] As a non-restrictive example only, according to Figure 1 and Figure 2 The tidal weir arrangement incorporates one or more buoyancy barriers in the channel, which can be configured for surge flood protection, as described below. Barrier 3 in channel 5 is raised by dewatering buoyancy element 13. This buoyancy element continues to rise as the water level rises above the normal high tide level. A specific safety limit can be set for the rise in water level upstream of the estuary. In this case, the gate used to block water flow through the turbine device may be closed to prevent further rise in water level upstream of the estuary. Buoyancy element 13 will continue to rise to increase the head difference on the buoyancy barrier and prevent any further flooding until buoyancy element 13 rises to a height that can be specified in the design phase as sufficient to protect the coastal area of ​​the upper estuary from storm surges and the maximum estimated sea-level rise due to global warming. Even beyond a theoretical point in the extreme flood event specified in the design, the change in the geometry of the buoyancy barrier will eventually inhibit further increases in the height of the buoyancy member and allow water to flow over the buoyancy member, which acts as a weir, and continue upstream into the estuary, just like any other form of barrier submerged by unforeseen sea-level rise caused by, for example, a tsunami.

[0064] As discussed further below, especially in reference Figure 9 and Figure 10 A two-way buoyancy barrier can be set up.

[0065] Figure 9 An exemplary configuration of one power generation module of the tidal weir is shown. This arrangement differs from the reference configuration. Figure 3 and Figure 4 The arrangement discussed includes both unidirectional and bidirectional barriers 3. In the arrangement shown, bidirectional barriers 3a and 3c are positioned within the air intake channel. Bidirectional barriers 3a and 3c are passive and reverse in response to changes in flow direction without external control. The two unidirectional barriers 3b in the central outflow channel can be operated in any situation by partially submerging a failed buoyancy element 13, causing the failed buoyancy element 13 to sink during power generation and then dehydrate again during tidal reversal to restore its function. If a malfunctioning barrier automatically sinks to the seabed under the pressure of the tide flowing over it, that barrier may also be operated passively. The success rate of such passive operation depends on the specific project environment.

[0066] It should be noted that alternative combinations of unidirectional and bidirectional buoyancy barriers are possible, as are different combinations of buoyancy and non-buoyancy barriers. Those skilled in the art will readily understand many suitable arrangements. The invention is not limited in this respect.

[0067] In any of the described arrangements, the inflow channel can be wider than the central outflow channel, and vice versa.

[0068] Considering this barrier, they can all be of conventional form, all of buoyancy, or a hybrid configuration. For example, the inflow channel can be fitted with a passive, two-way buoyancy weir, and the outflow channel can be fitted with a conventional barrier of any desired form. Those skilled in the art will readily conceive of many different configurations.

[0069] Figure 10 A side view of a bidirectional buoyancy barrier disclosed in UK patent application no. 2102604.2 is shown. Figure 10 This shows the complete translation of the buoyancy barrier during tidal reversal. This view is an end view, not a cross-section, showing the buoyancy weir / barrier extending between the two towers 2 in the arrangement shown. As indicated by the arrow on the right, Figure 10 The active flow in the diagram is from right to left, with the details in the solid lines showing the active positions of the weir components. The details shown in the dashed lines represent the positions of these components when the water flows against the current.

[0070] The membrane 12 is attached to the vertical centerline v of the tower wall above the anchor. The edges of the membrane 12 are folded against the wall to allow the buoyancy member 13 to move freely as the water level and flow direction change. It is important to note that in this way, the membrane 12 forms a bend B at each end of the buoyancy member, extending a short distance downstream of the buoyancy member 13, such that the top of the membrane 12 in the bend B is horizontal at no point lower than the top of the buoyancy member 13, and is folded away from the surface of the end wall 2, rather than dragging over it, to minimize abrasion damage to the membrane 12. It is also important to note that the membrane 12 is held against the end wall by water pressure and rises above the high water level line to minimize leakage losses. A slot 21 is provided in the flexible membrane 12 to provide a passage for water flow into the turbine device 4.

[0071] Figure 11 An exemplary flexible membrane 12 is shown in its unfolded shape for bidirectional operation between the combiner units of turbine units in two adjacent parallel towers 2. The location of the slot 14 is shown in the portion of the membrane folded vertically upward against the parallel plane of the adjacent tower. An unfolded shape of one of four directly adjacent unidirectional barriers is also shown, where the slot 14 is not required.

[0072] As can be clearly seen from the discussion in this article, a single power generation module consists of a single central upstream section, on either side of which are two downstream sections shared with adjacent modules.

[0073] The central upstream section preferably comprises a single bidirectional buoyancy weir, the membrane of which is anchored to the center of the estuary bed. This single bidirectional buoyancy weir self-regulates with each reversal of the tidal flow. Excessive seepage beneath the membrane that could lead to head loss and / or downstream land uplift is prevented or adequately mitigated by the central impermeable barrier 18 and / or a sufficiently long seepage path.

[0074] Each of the two downstream sections preferably includes two unidirectional buoyancy weirs, the upstream of which always functions according to the tidal direction to maintain the head difference between the upstream and downstream sides of the tidal weir. The downstream buoyancy weir fails and is always partially and actively submerged by floodwater or passively submerged due to downstream overtopping. This is achieved by installing a scour skirt to the underside of the tower during its construction as described above, and then preferably by ensuring… Figure 11 The dimension “x” (the length of the membrane that remains in contact with the riverbed at the estuary) is used to provide a sufficiently long seepage path to reduce seepage to an acceptable low amount, or, if necessary, an impermeable barrier is installed at each end of the tower as an anchor for the membrane, thereby preferably preventing inappropriate seepage and any subsequent downstream land heave from bypassing the four unidirectional buoyancy barriers in each power generation module.

[0075] It should also be noted that, as a matter of detailed design, some tidal weir devices may exist where environmental conditions and other design factors may lead to the selection of rock dumping levels over the entire or partial planar coverage area of ​​the tidal weir. For example, this approach may be chosen to mitigate localized scour at the weir's inlet and outlet, and in any case, to help reduce the sensitivity of the downstream estuary to uplift in the region.

[0076] Figure 12 The same unfolded shape of a typical flexible membrane 12 is disclosed, which is designed for unidirectional operation between diffusers of two adjacent parallel towers 2 arranged in a curved manner. Figure 12 The preferred trapezoidal planar shape of the tower is also disclosed to achieve the curved arrangement of the tidal weir while maintaining the relative parallel planes of the adjacent towers 2.

[0077] It is important to note that, for example Figure 1 and Figure 2 The overall structure of the tidal weir 1 shown, and the construction based on any of the above principles, can achieve the following desired design results:

[0078] • It can effectively maintain the natural tidal velocity and volumetric flow profile at various points along the estuary, minimizing any environmental disturbance to the overall seabed morphology. This is achievable because the number and size of the turbine units in each tower can be varied to match the natural flow velocity and flow rate at each module location on the weir. For example, in Figure 1 In the middle, the fourth module from the left is located in a deeper channel that carries more water than the other modules need to pass through, in order to maintain optimal performance for all modules while preserving the original flow profile of the entire route. Therefore, this module is designed to be longer than the others to accommodate more and / or larger turbine units.

[0079] UK patent application no. 2102604.2 discloses a first-order approximation in which the displacement of the buoyancy element in a buoyancy weir / barrier (a function of diameter) is primarily equal to the water weight behind a portion of the membrane, vertically above the downstream waterline, with an air gap below that portion. The relatively small self-weight of the buoyancy element itself, along with the self-weight of the membrane, is subject to a secondary downward force from the buoyancy reaction. In any case, this is essentially a very light and low-cost alternative to any robust structural tidal barrier (e.g., rockfill bunds or structural dam barriers) designed to resist the maximum overturning moment that the head difference between the upstream and downstream sides of such a barrier might exert on the barrier. As discussed herein, the longer the route, the greater the difference in financial costs that favors weirs and dams that include buoyancy barriers. Furthermore, with increasing water depth, the magnitude of buoyancy in the buoyancy weir required to achieve the same head difference will only increase slightly to match the minimal additional wet weight of the required longer flexible membrane. The cost of achieving a buoyancy weir for any given head difference is a first-order approximation and therefore independent of water depth. In contrast, the cross-sectional area of ​​any structural barrier (such as a gravity dam) increases proportionally to the square of the water depth, thus increasing the capital cost advantage of buoyancy weirs with increasing water depth.

[0080] The turbine device of this type disclosed herein provides a fish-friendly technology for approximately 80% of the water flow bypassing the turbine. The remaining approximately 20% of the flow can be filtered using a smaller and less expensive screen than required by any alternative technology. This screen can be easily cleaned with a mechanical device such as a brush or sprayer, or more simply, by a short cleaning using the reverse thrust of the turbine at low tide. Any debris thus removed can continue to pass through the turbine device in the remaining 80% of the flow.

[0081] While the tidal weir has been described for installation at tidal estuaries, it can also be installed in other bodies of water, such as for unidirectional flows across large rivers or flows that only occur at low tide. Furthermore, in relatively shallow waters with significant tidal currents, where the estuary bed may even be exposed at low tide, the shallow water depth limits the maximum diameter of any renewable energy power generation installation, requiring a large number of such installations and potentially a route longer than the estuary width can accommodate. Digging trenches along the route to accommodate larger diameter installations may not be ideal, as such trenches are prone to silting up and could concentrate all the larger generators in deeper waters, fundamentally altering the natural flow velocity distribution along the entire route and causing devastating environmental consequences. In this case, the disclosed arrangement allows for the deployment of a large number of power generation installations to match natural flow patterns, regardless of the available length of the tidal barrier arrangement.

[0082] When used in this specification and claims, the terms "comprising" and "including," and variations thereof, mean to include the specified features, steps, or entirety. These terms should not be construed as excluding the presence of other features, steps, or components.

[0083] The features disclosed in the preceding description, claims, or drawings, expressed in their particular form, or in the form of means for performing the disclosed functions, or in the form of methods or processes for obtaining the disclosed results, may suitably be used alone or in any combination of these features to implement the invention in its different forms.

[0084] While some exemplary embodiments of the invention have been described, the scope of the appended claims is not intended to be limited to these embodiments only. The claims should be interpreted literally and intentionally, and / or include their equivalents. Many alternative arrangements will be readily understood by those skilled in the art within the scope of the claims.

Claims

1. A tidal weir (1), comprising: Multiple spaced towers (2); Multiple barriers (3) between the towers are used to control the flow of water through the weir; as well as One or more turbine units (4); The towers mentioned therein include at least a first tower (2a), a second tower (2b), a third tower (2c), and a fourth tower (2d); The first tower (2a) is located between the second tower (2b) and the third tower (2c), the fourth tower (2d) is located on the opposite side of the third tower (2c) to the first tower (2a), and the first tower (2a) and the third tower (2c) house one or more of the turbine devices (4). A single bidirectional first barrier (3a) is provided between the first tower and the second tower, and a pair of unidirectional second barriers (3b) are provided between the first tower and the third tower, and a single bidirectional third barrier (3c) is provided between the third tower and the fourth tower. The barrier is configured such that: When the first barrier and the second barrier are in a first configuration, a first flow path through the weir is defined from a first side of the weir to a second side of the weir, and when the first barrier and the second barrier are in a second configuration, a second flow path through the weir is defined from a second side of the weir to a first side of the weir, and water flowing through the first flow path and the second flow path flows in the same direction through one or more turbines housed in the first tower; and When the third barrier is in the first configuration, a third flow path through the weir is defined from the first side of the weir to the second side of the weir, and when the third barrier is in the second configuration, a fourth flow path through the weir is defined from the second side of the weir to the first side of the weir, and water flowing through the third and fourth flow paths flows in the same direction through one or more turbines housed in the third tower; At least the first barrier and the third barrier each include an impermeable flexible membrane, a buoyancy component, and one or more tethers.

2. The tidal weir according to claim 1, wherein, Each of the second barriers includes an impermeable flexible membrane, a buoyancy member, and one or more tethers.

3. The tidal weir according to claim 1 or 2, wherein, The one or more turbines housed in the first tower face the one or more turbines housed in the third tower.

4. The tidal weir according to claim 3, wherein, The second tower houses one or more turbines facing away from one or more turbines housed by the first tower, and / or the fourth tower houses one or more turbines facing away from one or more turbines housed by the third tower.

5. The tidal weir according to claim 1, wherein, The first tower and the third tower, one or more turbine units housed by the first tower and the third tower, and the first barrier, the second barrier and the third barrier define the power generation module, wherein the weir includes a plurality of the power generation modules arranged adjacent to each other.

6. The tidal weir according to claim 1, wherein, In the plan view, the tower extends along the longitudinal axis.

7. The tidal weir according to claim 6, wherein, The longitudinal axes are arranged to be generally parallel to each other and / or generally along the direction of the tidal flow.

8. The tidal weir according to claim 6 or 7, wherein, The flow axis of the one or more turbine devices is substantially perpendicular to the longitudinal axis.

9. The tidal weir according to claim 1, wherein, The tower is basically rectangular in plan view.

10. The tidal weir according to claim 1, wherein, Adjacent towers consist of relatively parallel, generally flat surfaces.

11. The tidal weir according to claim 1, wherein, In use, the membrane includes a lower edge portion and an upper edge portion, the lower edge portion being fixed relative to the riverbed of the water body in which the weir is located, the membrane and the buoyancy member being attached to each other at the upper edge portion, and each of the one or more tethering chains including a first end and a second end, the first end being attached to the buoyancy member and / or to the membrane in the upper edge portion, and the second end being attached to an anchor.

12. The tidal weir according to claim 1, wherein, The buoyancy component includes a manifold through which water can be introduced into and / or discharged from the interior of the buoyancy component.

13. The tidal weir according to claim 12, wherein, The manifold is connected to the pump.

14. The tidal weir according to claim 1, wherein, Each of the one or more turbine units includes: A converging portion, the converging portion being connected to a first end of a mixing chamber, such that a venturi tube is defined between the end of the converging portion and the mixing chamber; A diffuser section connected to a second end of the mixing chamber, the diffuser being configured such that, in use, the pressure at the diffuser outlet is greater than the pressure at the venturi tube; At least a portion of the tube located in the converging portion, the converging portion defining an annular structure between the tube and the converging portion to form a first flow channel, and the tube defining a second flow channel within the tube; and A turbine that can be connected to a generator, wherein the turbine is located inside the tube.

15. The tidal weir according to claim 1, wherein, Each of the towers houses a set of the turbine units.

16. The tidal weir according to claim 1, wherein, One or more of the turbine devices include a turbine device barrier for selectively blocking water flow through the turbine device.

Images