Pressure chamber fish sluice

Abstract

The invention relates to a pressure-chamber fish sluice for overcoming greater height differences in transverse structures (3), such as, for example, flood protection structures or hydroelectric power stations, wherein two sluice chambers (6) with closure elements (7) for the upper (1) and lower bodies of water (2) are operated in opposite directions, so that fish can move upwards and downwards at the same time, wherein a device for energy conversion (8) is arranged in a hydraulic connection of the two sluice chambers (6), which allows an attraction current (5) to be generated, wherein each sluice chamber (6) has at least one compressible region (10) or each sluice chamber (6) is connected to a compressible region (10), and wherein the hydraulic connection of the sluice chambers (6) to the device for energy conversion (8) can be at least substantially closed.

Description

The invention relates to a pressure chamber fish sluice with which fish and other aquatic organisms can pass larger height differences at transverse structures, such as flood protection structures, weirs and dams of hydroelectric power plants or riverbed sills. Prior Art Pressure chamber fish sluices are already in use in several applications. For example, DE102012020781B3 describes a fish passage with a sluice chamber. Single-chamber fish sluices have the disadvantage that fish can only enter the sluice chambers temporarily. To allow for longer entry and exit times, there are also fish sluices with two mirror-inverted-operated sluice chambers, such as the fish sluice described in AT517218B1. This pressure chamber fish sluice enables gentle and low-maintenance operation of two sluice chambers with only one attraction flow, which flows through both sluice chambers. This is achieved by a hydraulic connection between the two chambers. An energy conversion device, such as a turbine or a throttle element, is provided in this connection behind protective elements that prevent fish from entering as much as possible. The fish sluice described in AT517218B1 has the disadvantage that gently overcoming larger height differences, for example over 10 m, is hardly possible because organisms have very little time to adapt to the pressure changes. Theoretically, the pressure change time could be extended by closing the gates very slowly, but such precise control or regulating would only be possible with great effort and would be very susceptible to external conditions, such as a shifting of the gate openings or uneven leaks. Furthermore, when the gates are almost closed, which is necessary for relatively long periods of time, this poses a danger to migrating fish and aquatic organisms for significantly longer periods due to very high flow velocities. Technical task The invention is therefore based on the technical problem of overcoming the disadvantage of the prior art and realizing a pressure chamber fish sluice which, due to two sluice chambers, enables the longest possible entry and exit times and also allows for overcoming large drop heights by ensuring that the pressure adjustment in the sluice chambers is carried out in a targeted, gentle manner and without significant technical regulating effort within a time period in which the migrating fish and other aquatic organisms can adapt. The object according to the invention is solved in particular by the features of the independent claim. Further advantageous embodiments are proposed according to the dependent claims. Solution according to the invention The invention relates to a pressure chamber fish sluice with two sluice chambers, each of which has at least one gate, such as a gate or a flap facing the upstream and downstream water side. The gates are operated such that one sluice chamber is open to the upstream water side and the other respective sluice chamber is open to the downstream water side. After, for example, a predetermined time or as soon as a defined number of fish have entered, the two open gates close, and then the two previously still closed gates open during the so-called switching phase. Fish that have entered the sluice chambers can then continue to migrate after this switching phase. The two sluice chambers of the present invention are hydraulically connected to each other in order to be able to direct a attraction flow from the upstream water side into the first sluice chamber, from there into the second sluice chamber, and then to the downstream water side. The connection has an energy conversion device, such as a turbine, a throttle orifice, a throttling gate, or a throttle flap. Entering this connection is largely prevented by protective elements attached to both sides, such as screens, grates, nets, perforated plates, or sieves. The hydraulic connection is designed such that it can be at least nearly completely closed for extended periods of time during the switching phase, so that little or no flow is possible from one sluice chamber to the other via this connection. This can be achieved either directly, for example, by adapting the provided throttling gates or throttle flaps, by additionally actuated blocking devices, for example, or by adapting the impeller blades when using a turbine as an energy conversion device. During the switching phase, the pressures in the sluice chambers are slowly adjusted to the pressures that will be present after the switching phase, i.e., the pressures of the upstream and downstream water side. To significantly reduce the control and regulating effort, to better compensate for small and variable leaks due to seal losses in the gates, and / or to avoid the need for less precise valves while still enabling the gentlest, most uniform, and controlled adjustment of the pressures possible, areas that are compressible are created in each of the two sluice chambers, or the sluice chambers are hydraulically connected to areas that are compressible. In the simplest case, the compressible areas can be designed as hydrophores or air chambers, i.e., areas containing a gas, such as air, in which the volume changes depending on the pressure. Furthermore, diaphragm expansion vessels or areas with pressure-dependent movable walls are possible, for example those similar to a hydraulic cylinder. If the compressible areas are not directly in the chamber, such as an air-filled chamber section, for example, a connecting by means of piping behind the protective elements of the sluice chamber connection can be advantageous for fish protection. The size of the compressible area depends on several factors, including, among other things, the size of the sluice chambers, the tightness of the gates, the height difference and / or the pressure change rate. There are several options for adjusting the pressures in the sluice chambers during the switching phase. In principle, the pressure should only change slowly, for example with a pressure change rate of 20 to 80 kPa / min (kilopascals per minute), to give the organisms sufficient time to adapt. The least effort required is to move the gates of the pressure chamber fish sluice only very slowly and in a precisely defined manner shortly before they are completely closed and at the beginning of the opening process, so that only small opening cross-sections are present. Since the attraction flow during the switching phase can be prevented by blocking the hydraulic connection between the two sluice chambers, a current that is dangerous for fish and other aquatic organisms hardly occurs anymore, and due to the compressible areas, it is generally possible to provide a gentle pressure adjustment. However, such a design is still always sluggish, susceptible to external influences, and a small danger is still posed by the gates. To improve this, the gates can be designed in such a way that, even at the same actuator travel, only small opening cross-sections result when the gates are almost closed or barely open. For example, the clear opening width behind the gate plate of a vertically movable gate can be reduced in the lower area by the frame or a baffle. Furthermore, protective measures such as screens, grates, nets, perforated plates, or sieves can be provided for fish protection when the gates are almost closed or barely open. However, it is more practical to achieve the pressure adjustment using additional, smaller valves or pumps. Some options are given below as examples. For example, in addition to the standard four gates, four further finely controllable valves can be installed, connecting the two sluice chambers to the upstream and downstream water side, respectively. By selectively opening the valves, the pressure in the chambers can be adjusted slowly and evenly. For improved fish protection, the connecting of the valves in the sluice chambers can take place after the protective elements of the hydraulic chamber connection are connected, and / or protective measures such as screens, grates, nets, perforated plates, or sieves can be provided at the connections. Furthermore, it is possible to additionally connect the two sluice chambers via at least one valve and at least one pump. In turn, connecting the components after the existing or additionally installed protective elements is advantageous for fish protection. In the first step, during the pressure adjustment in the switching phase, the valve is opened so that the pressures of the two sluice chambers adjust in as close correspondence as possible to the defined pressure change rate. The pump then builds up the pressures that will also be present in the sluice chambers after the switching phase. Various hydraulic circuits are possible for this purpose. The function of the pressure equalization valve could also take place from the blocking device of the hydraulic chamber connection if it can be finely adapted and if the compressible areas are sufficiently large. To better compensate for seal losses in the gates, at least one blockable pump and, advantageously, an additional valve parallel to the blockable pump per sluice chamber can connect the sluice chamber to the upstream or downstream water side for pressure adjustment. For pressure adjustment, the pressure in one chamber is increased by means of the pump or by opening the valve, while the pressure in the other sluice chamber is reduced by the pump or by opening the valve, depending on whether the components are designed with a connection in the direction of the upstream or downstream water side. Various well-known valve types can be used for pressure adjustment, including regulating valves, gates, ball valves, and sometimes also check flaps, i.e., valves or flaps, among others and the pump or pumps can also be designed to be regulatable. To enable a defined pressure adjustment, a constant or specific adjusted flow rate can be achieved via these components. Alternatively, pressure equalization can also be achieved by actively changing the volume or pressure of the compressible area, such as, for example, by moving a wall or introducing a gas or liquid, possibly behind a membrane. The invention is now further explained with reference to four exemplary embodiments which are schematically represented in the drawings, wherein Fig. 1a shows a sectional view of an embodiment of the pressure chamber fish sluice without the additional pumps and valves which are useful for pressure adjustment, Fig. 1b shows a top view, cut in the middle of the sluice chamber, of the first embodiment of the pressure chamber fish sluice without the additional pumps and valves which are useful for pressure adjustment, Figs. 2a to 2d show a top view, cut in the middle of the sluice chamber, of a second embodiment of the pressure chamber fish sluice with additional valves for the upstream and downstream water side, Fig. 3a shows a top view, cut in the middle of the sluice chamber, of a third embodiment of the pressure chamber fish sluice with an additional connection between the two sluice chambers, the connection having a valve and a bidirectional pump, Figs. 3b to 3e show further possible hydraulic circuits with pumps and valves for the third embodiment of the pressure chamber fish sluice and Figs. 4a and 4b show a top view, cut in the middle of the sluice chamber, of a fourth embodiment of the pressure chamber fish sluice, in which the sluice chambers are connected to the upstream water side by valves and pumps. In the first embodiment, shown in Figs. 1a and 1b, the structure of the pressure chamber fish sluice according to the invention is illustrated. In Fig. 1a, it can be seen that the water level 5 in the upstream water side 1 is higher than in the downstream water side 2 after the transverse structure 3. The pressure chamber fish sluice projects through the transverse structure 3, is installed flat in this exemplary embodiment, and has a continuous connection to the riverbed 4. The pressure values, given in this and subsequent figures in kPa (Kilopascals), indicate, for example, a height difference of approximately 10 meters between the upstream water side 1 and the downstream water side 2. Fig. 1b shows the four gates 7 of the pressure chamber fish sluice, the two sluice chambers 6, the connection between the two sluice chambers 6 using the energy conversion device 8, which is sealable, as well as the protective elements 9 that prevent fish from entering the connection. A connection, by means of a pipeline from each sluice chamber 6, to the compressible area 10, here designed in exemplary fashion as a hydrophore, is also shown schematically, wherein the connection to the two sluice chambers 6 takes place behind the protective elements of the connection, for example. Fig. 2a shows the previously shown pressure chamber fish sluice with additional valves 11 suitable for gentle pressure adjustment. The valves 11 connect each sluice chamber 6 to the upstream water side 1 and the downstream water side 2, respectively. In Fig. 2a, the gate 7 of the sluice chamber 6 toward the downstream water side 2, which is shown on top, is open, and the gate 7 of the sluice chamber 6 toward the upstream water side 1, shown on the bottom, is open. The pressure in the sluice chambers 6 equilibrates to that on the upstream water side 1 and on the downstream water side 2, respectively, and fish can enter the sluice chambers 6 from both sides, guided by a attraction flow 15. All four valves 11 are closed, which, as with the gates 7, is symbolized by a black filling. 1.     Fig. 2b shows the switching phase of the pressure chamber fish sluice in its initial phase. The two previously opened gates 7, as well as the connection between the two sluice chambers 6 using the energy conversion device 8, have been closed. Then, the valve 11 toward the upstream water side 1 of the sluice chamber 6, shown on top, has been opened so that a pressure equalization current 16 flows into the corresponding sluice chamber 6 and continues to stream in the direction of the compressible area 10. This increases the pressure in sluice chamber 6. In the sluice chamber 6 shown on the bottom, the valve 11 is opened toward the downstream side 2, causing a pressure equalization current 16 from the compressible area 10 to flow to the downstream side 2 and causing the pressure in sluice chamber 6 to decrease. Fig. 2c illustrates the switching phase of the pressure chamber fish sluice at a later point during the switching phase. It can be seen that the pressure in the sluice chamber 6 shown on top has increased further, and there is also more water in the compressible area 10 of this sluice chamber 6. In the sluice chamber 6 shown at the bottom, however, the pressure has decreased further, and water has flowed out of the compressible area 10. Fig. 2d illustrates the pressure chamber fish sluice after the switching phase. The gates 7, which were closed before the switching phase, have opened after complete pressure adjustment. This allows the fish that previously entered into the sluice chambers 6 to continue their migration, guided by the attraction flow 15 which is enabled again by opening the chamber connection. The two valves 11 that were opened for pressure adjustment close again. The next switching phase of this pressure chamber fish sluice would take place in mirror-inverted fashion; that is, the gates 7 and valves 11 of the respective other sluice chambers 6 are actuated according to the sequence described. In Fig. 3a, pressure adjustment is achieved with the aid of a pump 12 that operates in both flow directions (bidirectional pump), for example, and a valve 11 connecting the two sluice chambers 6. During the switching phase, the connection of the two sluice chambers 6 to the energy conversion device 8 is closed. Then, the valve 11 is opened, and a pressure equalization current 16 flows through the valve 11 and the bidirectional pump 12 from the sluice chamber 6 with the higher pressure to the sluice chamber 6 with the lower pressure until pressure equalization has occurred. Then, the bidirectional pump 12 continues to convey the pressure equalization current 16 in the same direction until the pressure states in the sluice chambers 6 approximately correspond to those after the switching phase. Fig. 3b shows the series circuit of a bidirectional pump 12 with a valve 11 as shown in Fig. 3a. Fig. 3c shows another example of a circuit in which two unidirectional pumps 13 that can be blocked by a valve 11 are designed in parallel. Fig. 3d shows a series circuit of a bidirectional pump 12 with a valve 11. A valve 11 is arranged in parallel with this, the pressure equalization taking place using the valve until the pump, via actuating, ensures the required pressure difference. Fig. 3e shows a circuit in which a pressure equalization current 16 in both directions is enabled with only one unidirectional pump 13 by selectively actuating the valve 11. For this purpose, two diagonally arranged valves 11 each are actuated. In the hydraulic circuits of Figure 3, the most airtight possible gates 7 are required because uneven leakage prevents good pressure adjustment. One solution could be to use additional valves 11 to enable an equal leakage flow. In Fig. 4a, pressure adjustment in the illustrated pressure chamber fish sluice is enabled using valves 11 and unidirectional pumps 13. In the process, each sluice chamber 6 is connected to the upstream water side 1 via a valve 11 and a unidirectional pump 12 arranged in parallel, the pump being blockable with a check valve, for example. In the process, the upstream-side connection takes place, for example, behind a fine screen 14 for protection. The connections in the sluice chambers 6 take place, for example, behind the existing protective elements 9. In principle, a circuit with only one unidirectional pump 13 and a valve 11 arranged in parallel is also possible for each sluice chamber 6, provided that this pump is connected to both sluice chambers 6 via one valve 11 each. Fig. 4b shows how the pressure adjustment of the fourth exemplary embodiment takes place. It can be seen that in the sluice chamber 6 illustrated on top, the valve 11 is opened, a pressure equalization current 16 flows into the sluice chamber 6 and the compressible area 10 of this sluice chamber 6, and thus the pressure increases. In the sluice chamber 6 illustrated on the bottom, however, a pressure equalization current 16 is conveyed from the sluice chamber 6 and its compressible area 10, to the upstream water side 1 by the unidirectional pump 13, thereby the pressure in this sluice chamber 6 decreases. After the pressure adjustment is complete, the gates 5   7 and the connection between the two sluice chambers 6 can be reopened, the pump switched off, and all valves 11 closed. The next switching phase is carried out in a similar manner to the one described here. However, the other respective valves 11 and the other respective unidirectional pump 13 are actuated.

Claims

1. A pressure chamber fish sluice consisting of two mirror-inverted operated sluicechambers (6) each with gates (7) to the upstream water side (1) and the downstream water side (2), in which the two sluice chambers (6) are connected to an energy conversion device (8) for releasing a attraction flow (15), characterized in that each sluice chamber (6) has at least one area with a compressible gas or a pressure-dependent movable wall section, such as a membrane or movable wall, for example, or is connected to this compressible area (10) and in that the connection of the two sluice chambers (6) with the energy conversion device (8) can be at least largely sealed.

2. The pressure chamber fish sluice according to claim 1, characterized in that at least onevalve (11) each is provided per sluice chamber (6) from the sluice chamber (6) to the upstream water side (1) and from the sluice chamber (6) to the downstream water side (2), i.e. a total of at least 4 valves (11), for pressure adjustment.

3. The pressure chamber fish sluice according to claim 1, characterized in that at least onebidirectional pump (12), or at least one unidirectional pump (13) is provided for pressure adjustment, optionally blockable, the pump connecting the two sluice chambers (6).

4. The pressure chamber fish sluice according to claim 3, characterized in that at least onefurther valve (11) is arranged in parallel to the bidirectional pumps (12) or to the unidirectional pumps (13), by means of which a pressure equalization is enabled in a precisely defined manner and / or optionally the direction of the pressure equalization current (16) can be adjusted with the valve.

5. The pressure chamber fish sluice according to claim 1, characterized in that for pressureequalization, per sluice chamber (6) at least one optionally blockable unidirectional pump (13) or one optionally blockable bidirectional pump (12) and optionally a valve (11) that is arranged in parallel thereto connect the sluice chamber (6) to the upstream water side (1) or alternatively to the downstream water side (2).

6. The pressure chamber fish sluice according to claim 1, characterized in that four veryprecisely movable gates (7) are used for pressure adjustment, by means of which very small nonfish-passable opening cross-sections can be selectively enabled.

7. The pressure chamber fish sluice according to claims 1 to 5, characterized in that in theconnections of the valves (11) or the pumps (12, 13) to the upstream water side (1), the downstream water side (2), or the sluice chambers (6), grates, nets, perforated plates, or sieves are provided to protect fish, or the valves (11) and pumps (12, 13) are connected behind the protective elements (9) of the energy conversion device (8), i.e., to an area that no fish can reach.

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