VENTURI EFFECT SIPHON ENERGY GENERATION SYSTEM COUPLED WITH AN AIR TURBINE

Abstract

The invention relates to an energy generation system 1 contributing to climate cooling, comprising: A siphon 2 connecting an upstream reservoir 6 to a downstream reservoir 7 where the flow of a liquid 5 is accelerated and the pressure is reduced, converting hydraulic energy into aerodynamic energy; An air introduction device 9 coupled to the Venturi effect zone 8 of an air turbine 3, supplying the zone with depressurized air; The external air turbine 3, drawing in outside air to supply the siphon 2 via the device 9 and converting the aerodynamic energy into mechanical energy. The system operates according to Bernoulli's equation, the acceleration of the liquid in the Venturi effect zone 8 creating a depressurization that draws in outside air. This air, passing through the turbine 3, generates mechanical energy before being introduced into the siphon 2. Figure to be published with the abstract: Figure 1

Description

Title of the invention: SIPHON POWER GENERATION SYSTEM WITH EFFECT VENTURI COUPLED WITH AN AIR TURBINE technical field

[0001] The present invention relates to the field of energy generation systems exploiting hydraulic energy.

[0002] More particularly, it relates to a system using a siphon with a Venturi effect zone to draw in air and drive an air turbine coupled to an electrical power generator. Previous technique

[0003] Below, we describe the prior art known from which the invention was developed.

[0004] Numerous systems have been developed to generate energy from hydraulic sources. Conventional hydroelectric power plants use the force of water flowing from an upper reservoir to a lower reservoir to drive turbines connected to alternators.

[0005] However, these installations generally require the construction of large dams and have a significant environmental impact by altering aquatic and terrestrial ecosystems.

[0006] Other technologies harness the energy of ocean currents, waves, or tides. Tidal turbines, similar to underwater wind turbines, use the force of currents to rotate their blades and generate electricity. Wave energy systems convert wave energy into electricity via various mechanisms such as oscillating water columns or articulated floating bodies. Tidal power plants, for their part, take advantage of the ebb and flow of the tides, often by damming estuaries.

[0007] Although promising in terms of energy, these systems remain complex, expensive and can also disrupt marine environments.

[0008] In view of the state of the art, current systems for generating energy from hydroelectric sources have several limitations. Conventional hydroelectric power plants have a major environmental impact and are only profitable for large-scale installations. Technologies harnessing marine energy remain complex, expensive, and can also disrupt ecosystems.

[0009] There is therefore a need for an electrical power generation system 1 that is efficient, economical, easy to implement, environmentally friendly and requires little maintenance.

[0010] This system should be able to adapt to different reservoir configurations and elevation changes, while being minimally invasive to aquatic ecosystems. Summary of the invention

[0011] The invention aims to overcome these drawbacks. The following presents a simplified summary of selected aspects, embodiments, and examples of the present invention in order to provide a basic understanding of the invention. However, this summary does not constitute an exhaustive overview of all aspects, embodiments, and examples of the invention. Its sole purpose is to present selected aspects, embodiments, and examples of the invention in a concise form as an introduction to the more detailed description of the aspects, embodiments, and examples of the invention that follow the summary.

[0012] A first aspect of the invention relates to an energy generation system configured to exploit the flow of a liquid in order to generate usable mechanical energy, without external energy input, the energy generation system comprising a siphon, an air introduction device and an air turbine.

[0013] In this system, - the siphon is configured to connect the flowing liquid from an upstream reservoir to a downstream reservoir, the upstream and downstream reservoirs being located at different altitudes, said siphon further being equipped with a constriction forming a Venturi effect zone where the flow of the liquid is accelerated and the pressure is decreased according to Bernoulli's equation, thus converting the hydraulic energy of said flowing liquid into aerodynamic energy by drawing in outside air, - the air introduction device is coupled to the Venturi effect zone and the air turbine, the air introduction device being configured to create an intake of outside air, via the air turbine, by the depression generated in said Venturi effect zone and transfer the aerodynamic energy thus obtained to the siphon, and - the air turbine is disposed outside said siphon and configured to be supplied with outside air and to supply said siphon via the air introduction device, said air turbine being further configured to expand the aspirated outside air and convert said aerodynamic energy into mechanical energy.

[0014] According to other optional features of the retaining article, the first aspect of the invention may optionally include one or more of the following features, alone or in combination: - The system further includes an electric generator configured to be coupled to the air turbine and to generate electrical energy from mechanical energy. - The system further includes, * means of measuring air pressure at the Venturi effect zone of the siphon, * means for controlling the flow rate of outside air drawn in by the air turbine, including control of the rotational speed of the electric generator coupled to said air turbine, and * a first control unit configured to automatically control, based on the air pressure measured at the Venturi effect zone, the rotation speed of the electric generator and therefore the flow of outside air drawn in by the air turbine in order to regulate the flow of the liquid flowing in the siphon without human intervention. - the first control unit is configured to control the rotational speed of the air turbine and / or the electric generator in order to optimize the operating point of the system at a speed for which there is a reversal between an increase in electrical power generated and a reduction in the flow rate of the liquid flowing in the siphon. - The first control unit is configured to control the rotational speed of the air turbine and / or the electric generator in such a way as to: * increase the flow rate of the liquid passing through the turbine in the siphon with an energy efficiency lower than the maximum efficiency, in order to manage the liquid level in the upstream reservoir during periods of flooding, and / or * reduce the flow rate of the turbined liquid in the siphon to a predetermined value with an energy efficiency lower than the maximum efficiency, in order to maintain a minimum flow of the liquid during periods of low water, thus widening the range of use of the system in terms of flow rate of the liquid in flow compared to an operation at maximum energy efficiency. - the system also includes, * a level sensor configured to detect when the liquid level in the upstream tank falls below a predetermined threshold, * a self-priming valve coupled to the siphon and a second control unit, said second control unit being configured to, when the level sensor detects a low level, command the opening of the self-priming valve in order to cause a controlled priming of the siphon allowing to maintain a minimum flow of said liquid towards the downstream tank. - The air turbine and / or the electric generator are located in a de-sealed space isolated from the aquatic environment of the siphon, said de-sealed space facilitating the maintenance of said air turbine and electric generator. - The air turbine is configured to exploit a pressure difference between the ambient air PI and the expanded air P2 at the outlet of the air turbine, said pressure difference being created by the Venturi effect in the siphon, such that the ratio between the cooling power of the intake air and the mechanical power produced by the turbine is greater than or equal to 1. - the system further includes a control device configured to adjust the air flow rate Dair and the water flow rate Deau in the siphon according to the temperature of the air or liquid to be cooled, said control device being coupled to the air introduction device and the air turbine to regulate the pressure of the introduction of air into the siphon. - the control device is configured to maintain the air introduction pressure in the siphon between PO-Palt-Pvent and PO-Palt, where PO is atmospheric pressure, Palt is the pressure due to altitude, and Pvent is the pressure due to the Venturi effect, so as to simultaneously optimize the production of mechanical energy and the cooling of the air or liquid. - the second arm of the siphon is configured to extend into the downstream reservoir over a sufficient length to maximize heat exchange between the cooled air circulating in said second arm and the surrounding liquid, said second arm comprising a heat exchange wall designed to promote heat transfer between the cooled air and the liquid in the downstream reservoir, thus enabling the cooling of said liquid before the air rises to the surface.

[0015] A second aspect of the invention relates to a flour mill comprising: - a mill configured to grind cereal grains and produce flour, - a power generation system according to the first aspect of the invention, in which: — the upstream reservoir corresponds to a water reservoir upstream of the mill, — the downstream reservoir corresponds to a tailrace canal downstream of the mill, — the siphon is placed between a millrace supplying water to the mill and the tailrace, exploiting a difference in altitude between the upstream and downstream reservoirs, — the air turbine is coupled to an electric generator configured to produce electricity from the mechanical energy generated by the expansion of air in the air turbine, and — electrical connection means configured to supply at least part of the electricity produced by the electric generator to milling equipment and / or to inject said electricity into an external electrical network.

[0016] A third aspect of the invention relates to a method for producing energy from the potential energy of a liquid, comprising, - A step of accelerating the flow of the liquid in a Venturi effect zone of a siphon connecting an upstream reservoir to a downstream reservoir, the upstream and downstream reservoirs being located at different altitudes, so as to create a localized depression which allows the aspiration of outside air via an air introduction device coupled to said Venturi effect zone, thus converting the hydraulic energy of said liquid in flow into aerodynamic energy, - A step of transferring ambient air to an air turbine disposed outside said siphon, then introducing this air, after passing through the air turbine, into the siphon via said air introduction device coupled to said air turbine, and - A stage of expansion of the outside air drawn into the air turbine, the air turbine converting the aerodynamic energy into mechanical energy, the process being implemented without external energy input.

[0017] According to other optional features of the retaining article, the third aspect of the invention may optionally include one or more of the following features, alone or in combination: - the process further includes a step of automatic control and control of the flow of outside air drawn in by the air turbine via a control of the rotation speed of the electric generator coupled to said air turbine, as a function of a measurement of the air pressure at the level of the Venturi effect zone, so as to regulate the flow of the liquid flowing in the siphon without human intervention. - the process also includes the following steps: * detect, using a level sensor, when the liquid level in the upstream tank falls below a predetermined threshold, * In response to said detection, command the opening of a self-priming valve coupled to the siphon in order to cause a controlled depriming of said siphon, * regulate the flow of outside air drawn in by the air turbine so as to maintain a minimum flow of said liquid flowing from the upstream reservoir to the downstream reservoir after said priming. Brief description of the drawings

[0018] Other features and advantages of the invention will be better understood from the following description and with reference to the accompanying drawings, given by way of illustration and not limitation.

[0019] [Fig-1] Fig. 1 represents a diagram of an energy generation system according to a first embodiment of the invention.

[0020] [Fig.2] The [Fig.2] represents a diagram of an energy generation system 1 according to a second embodiment of the invention.

[0021] [Fig.3] The [Fig.3] represents a diagram of an energy generation system 1 according to a third embodiment of the invention.

[0022] [Fig.4] Fig.4 represents a cross-section of a siphon according to an embodiment of the invention.

[0023] [Fig. 5] Figure 5 illustrates examples of simulation results in the form of graphical representations, showing the velocity profile of the liquid ("velocity magnitude") in the energy generation system 1 according to one embodiment of the invention.

[0024] [Fig.6] The [Fig.6] illustrates examples of simulation results in the form of graphical representations, showing the static pressure and volume fraction profiles in the power generation system 1 according to one embodiment of the invention.

[0025] [Fig.7] The [Fig.7] represents a diagram of an energy production process according to an embodiment of the invention.

[0026] The figures do not necessarily respect the scales, particularly in section, for illustrative purposes.

[0027] Aspects of the present invention are described with reference to flowcharts and / or functional diagrams of processes, apparatus (systems) according to embodiments of the invention.

[0028] In the figures, flowcharts and functional diagrams illustrate the architecture, functionality, and operation of possible implementations of systems and processes according to various embodiments of the present invention. In this regard, each block in the flowcharts or block diagrams can represent a system, device, or module, which includes one or more executable instructions for implementing the specified logical function(s). In some implementations, the functions associated with the blocks may appear in a different order than that shown in the figures. For example, two blocks shown successively may, in fact, be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order, depending on the functionality involved.Each block in the schematic diagrams and / or flowchart, and combinations of blocks in the schematic diagrams and / or flowchart, can be implemented by special hardware systems that perform the specified functions or actions, or perform combinations of special hardware. Description of the implementation methods

[0029] Below, we describe a summary of the invention and the associated vocabulary, before presenting the disadvantages of the prior art, and finally showing in more detail how the invention remedies them.

[0030] In the following description, the term "flowing liquid" as used in the invention refers to a liquid in motion, flowing from one point to another in a single direction, under the influence of gravity or a pressure difference. This flowing liquid is characterized by a flow rate and a velocity and takes the shape of the conduit that contains it. Its flow can be laminar or turbulent depending on the conditions. It should be noted that the movement of the liquid can be caused by a variety of forces and mechanisms, whether mechanical, electromagnetic, thermal, or resulting from molecular interactions. These forces can act alone or in combination, thus creating diverse and complex flow conditions.

[0031] The term "siphon" in the sense of the invention can correspond to an essentially closed and continuous conduit, but which may have certain openings, allowing the flow of a liquid from one reservoir to another located at a lower altitude, without external energy input, the flow being initiated by suction at one of the ends.

[0032] The term "Venturi effect" in the context of the invention refers to a hydrodynamic phenomenon that occurs when a flowing fluid passes through a constriction in cross-section. According to Bernoulli's principle, the fluid's velocity increases and its pressure decreases at the point of constriction. This effect is exploited in the siphon according to the invention to create a suction of outside air to the siphon.

[0033] The expression "Venturi effect zone" in the sense of the invention can correspond to a narrowed portion of the siphon inducing, in accordance with Bernoulli's principle, an acceleration of the flow of the liquid and a decrease in static pressure at that point.

[0034] The term "air introduction device" in the context of the invention can refer to a means for drawing outside air, at a controlled pressure, into the siphon at the Venturi effect zone, due to the negative pressure present there. This device can, for example, consist of one or more orifices formed in the siphon wall. The size, number, and arrangement of these orifices are designed to directly influence the quantity of air introduced and, consequently, the pressure in the siphon.

[0035] The term "air turbine" in the context of the invention may refer to a device comprising one or more wheels equipped with blades, or to any other alternative system, converting the kinetic energy of the outside air drawn in and flowing through it into energy Mechanical or electrical, by expansion of the air. This conversion can be achieved through rotation, oscillation, deformation, or any other mechanism exploiting air movement. The turbine can be axial, radial, hybrid, or even utilize innovative concepts such as: - Oscillating turbines, where a cylinder oscillates under the effect of the wind, - Piezoelectric generators, using the deformation of specific materials, and - Elastic deformation systems, exploiting the flexibility of certain structures. Although alternative technologies are often at the experimental stage, they demonstrate the diversity of possible approaches in the design of air turbines.

[0036] The term "electric power generator" in the context of the invention can refer to a machine that converts the mechanical energy supplied by the air turbine into electrical energy by electromagnetic induction. This could be, for example, an alternator or a direct current electric generator.

[0037] The prior art in the field of hydroelectric power generation mainly comprises systems using hydraulic turbines directly immersed in the flowing liquid, such as Pelton®, Francis® or Kaplan® turbines, the turbine being driven by the flow of the liquid.

[0038] However, these systems have several drawbacks: - the need to have complex moving parts directly in the liquid, which creates disturbances in the liquid flow and reduces the available flow rate, while also posing maintenance, reliability, and cost problems, - a potentially significant environmental impact due to the disruption of the natural flow of the liquid and the risks to aquatic wildlife, - The efficiency of this type of system is often limited by mechanical losses at the turbine level, and - siting constraints related to the need for a significant difference in elevation between the upstream and downstream reservoirs.

[0039] The invention offers an innovative solution to these problems by proposing an electrical energy generation system without moving parts in a flowing liquid, thus reducing maintenance costs and environmental impacts.

[0040] In practice, the invention exploits the flow of a liquid in order to generate usable mechanical energy, without external energy input.

[0041] For this purpose, the invention exploits the Venturi effect to create a depression drawing in outside air, which is then expanded in an air turbine which is coupled to an electric power generator, all outside the flowing liquid.

[0042] Thus, the invention relates to an energy generation system according to the invention comprising several main elements which interact to produce energy efficiently and ecologically.

[0043] The energy generation system 1 according to the invention comprises a siphon 2, an air introduction device 9 and an air turbine 3.

[0044] The siphon 2 is configured to connect a liquid 5 flowing from an upstream reservoir 6 to a downstream reservoir 7.

[0045] The term “reservoir” refers to a container, tank or basin intended to contain and store a liquid, here for the purpose of supplying a flow.

[0046] The term "upstream" refers to what is located upstream, that is, at the origin of the flow of the liquid 5, upstream of the point considered. In the context of the invention, the upstream reservoir 6 is the one from which the liquid 5 flows to the downstream reservoir 7 via the siphon 2.

[0047] The term "downstream" refers to what is located downstream, that is, in the direction of the flow of the liquid 5, after the point in question. In the context of the invention, the downstream reservoir 7 is the one into which the liquid 5 flows from the upstream reservoir 6 via the siphon 2.

[0048] Thus, the upstream reservoir 6 and downstream reservoir 7 are in fluidic communication, that is to say, they are connected by the siphon 2 which allows the liquid 5 to flow from one to the other. The siphon 2 thus ensures the continuity of the flow of the liquid 5 between the two reservoirs.

[0049] Furthermore, the reservoirs 6 and 7 are located at different altitudes. In practice, the upstream reservoir 6 is located at a strictly higher altitude than the downstream reservoir 7. This difference in altitude aids the natural flow of the liquid 5 by exploiting gravity.

[0050] Advantageously, the flow rate of the liquid 5 flowing between the upstream reservoir 6 and the downstream reservoir 7 is between 0.1 m³ / s and 20 m³ / s. This ensures that the system operates at high and constant performance levels.

[0051] The siphon 2 is further provided with a constriction forming a Venturi effect zone 8 where the flow of the liquid 5 is accelerated and the pressure of the liquid 5 is decreased according to Bernoulli's equation.

[0052] In the context of the Venturi effect and siphons, "constriction" refers to a gradual and controlled reduction in the cross-sectional area of ​​the conduit through which the fluid flows. This constriction is not abrupt but is characterized by a continuous decrease in cross-sectional area along a certain distance of the conduit. In the specific case of the siphon 2 according to the invention, the constriction is manifested by a gradual reduction in the cross-sectional area of ​​the tube as it rises from the upstream reservoir 6. up to the vicinity of the summit. This particular geometric configuration creates a Venturi effect zone 8 at the highest point of siphon 2, where the section is narrowest.

[0053] The constriction plays an important role in creating the Venturi effect. Indeed, according to Bernoulli's principle, reducing the cross-section leads to an increase in the fluid flow velocity and, consequently, a decrease in its pressure. It is precisely this pressure drop that generates a suction force, used in the siphon 2 to draw in outside air.

[0054] It is important to note that the constriction is not permanent: after the narrowest point, the cross-section of the siphon 2 gradually widens again during the descent towards the downstream reservoir 7. This asymmetrical configuration of the constriction, with a reduction followed by a widening, is essential to optimize the Venturi effect and ensure the proper functioning of the siphon 2.

[0055] In practice, the Venturi effect zone 8 is located at the top of the siphon 2, which starts from the upstream reservoir 6, rises vertically to a height L (m) and descends towards the downstream reservoir 7 over a distance L+H (m). The cross-section of the siphon 2 is continuously reduced during the ascent from the upstream reservoir 6 to the vicinity of the top, then continuously increases again during the descent towards the downstream reservoir 7.

[0056] In one example, the difference between the altitude of the Venturi effect zone 8 and the upstream reservoir 6 is within a value ranging from +1 meter to +10 meters. This configuration maximizes the suction effect in the siphon 2 without risk of loss of prime.

[0057] This Venturi effect creates a low-pressure area at the Venturi effect zone 8, which draws in outside air via the air intake device 9. This intake results from the pressure difference between the outside air and the low-pressure area created by the Venturi effect. The low pressure in the Venturi effect zone 8 is due to two factors: firstly, the difference in elevation of the water rising a height L relative to the upper reservoir (1 m = 10 kPa in water), denoted Pait (Pa), and secondly, Bernoulli's equation, which gives a low pressure proportional to the square of the water velocity accelerated by the reduction in cross-section in the Venturi effect zone 8, denoted Pvent (Pa).

[0058] The acceleration of the flow and the pressure drop in the Venturi effect zone 8 are key elements for the efficient operation of the energy generation system 1. These phenomena make it possible to convert the hydraulic energy of the flowing liquid 5 into aerodynamic energy in the form of air intake.

[0059] The energy generation system 1 also includes an air introduction device 9 coupled to the Venturi effect zone 8. Air is introduced at a controlled pressure, which determines the air flow rate Dair and the water flow rate Deau in the siphon 2. The hydraulic energy of the flowing liquid 5 is thus exploited to draw in air in siphon 2. The air introduction device 9 is also coupled to the air turbine 3.

[0060] The air introduction device 9 is configured to create an outside air intake by the depression generated in the Venturi effect zone 8. This depression converts the hydraulic energy of the flowing liquid 5 into aerodynamic energy in the form of air intake.

[0061] The air flow rate and the water flow rate are proportional to the pressure at which the air is introduced at the top of the siphon 2: - If air is introduced at the resulting pressure at the top of siphon 2, taking into account the three components (PO: atmospheric pressure - Pait: pressure due to altitude - Pvent: pressure due to the Venturi effect), the air flow rate Dair is zero and the water flow rate Deau is maximum. - If air is introduced at a pressure which tends by value greater than (PO - Paît), namely the pressure at the top of siphon 2 in the absence of Venturi effect, the flow rate Dair is positive (air sucked in by the water) and the water flow rate Deau is reduced. - When the pressure of the air introduced at the top of siphon 2 is at (PO-Palt), this is the beginning of the loss of prime of siphon 2 and the water flow rate Deau tends towards zero.

[0062] This allows outside air to be introduced into the siphon 2 without any mechanical components, relying solely on hydrodynamic effects. In other words, the air introduction device 9 uses the low pressure created by the Venturi effect to draw in outside air, thus improving the system's efficiency. The resulting intake of outside air then feeds an air turbine 3. The aerodynamic energy of the moving air is then transmitted to the air turbine 3. This air intake is the primary mechanism that drives the turbine, unlike conventional wind turbines where wind pressure rotates the blades. Therefore, there is a whole range of air pressures (between (P0-Palt-Pvent) and (P0-Palt)) within which the system is capable of drawing in a certain airflow rate Dair. Fixing this pressure (which is actually a depression relative to PO) is equivalent to fixing the air flow rate Dair and the water flow rate Deau in siphon 2.

[0063] The air turbine 3 is another main element of the power generation system 1, which is located outside said siphon 2 and configured to be supplied with outside air drawn from the siphon 2 via the air inlet device 9. This configuration allows the air turbine 3 to operate as a reverse wind generator, where suction replaces wind thrust.

[0064] In a particular embodiment, the recovery by the air turbine 3 of the outside air drawn into the siphon 2 by the air inlet device 9 is made possible by means of at least one connecting duct physically linking these two elements. The air inlet device 9 may include at least one orifice An air intake opens into siphon 2 at the level of the negative pressure zone created by the Venturi effect. This intake opening is extended by at least one duct that passes through the wall of siphon 2 to exit to the outside and connect to the air outlet of the air turbine 3. In this particular implementation, this duct carries the outside air drawn into siphon 2 via the air turbine 3 located outside the siphon 2. It ensures physical continuity between the intake zone in siphon 2 and the air outlet of the air turbine 3. This duct allows the transfer of aerodynamic energy from the air turbine 3 to siphon 2. Seals at the wall penetration can be used to ensure airtightness.

[0065] The air turbine 3 is further configured to expand the aspirated outside air and, after expansion to supply the sealed duct connected to the air introduction device 9, convert the aerodynamic energy into mechanical energy.

[0066] Indeed, during its expansion in the air turbine 3, the aerodynamic energy of the air is converted into mechanical energy, for example into rotational mechanical energy.

[0067] In summary, the hydraulic energy of the flowing liquid 5 is first converted into aerodynamic energy by drawing in air through the Venturi effect. This aerodynamic energy is also used by the air turbine 3, which converts it into mechanical energy during the expansion of the drawn-in air. We thus have an energy conversion chain: hydraulic → aerodynamic → mechanical, which allows us to exploit the flow of the liquid 5 to generate usable mechanical energy, all without any external energy input.

[0068] Furthermore, the absence of any moving parts in the flowing liquid 5 and the use of a conventional air turbine 3, separate from the flow of the flowing liquid 5, are significant advantages in terms of maintenance, reliability, and risk reduction for aquatic fauna. Thus, by design, the system 1 is inherently 100% fish-friendly, thereby ensuring optimal protection of aquatic biodiversity.

[0069] In summary, the energy generation system 1 exploits a cascade of pressure differences to create a continuous airflow and generate mechanical energy.

[0070] The overall operation can be explained schematically as follows: System 1 comprises three distinct pressure zones: - PI at the inlet of air turbine 3 (e.g., approximately 100 kPa, atmospheric pressure), - P2 at the outlet of air turbine 3 (e.g., approximately 80 kPa), and - P3 at the highest point of siphon 2 (e.g., less than 80 kPa). This configuration creates a pressure gradient PI > P2 > P3, which is favorable to airflow.

[0071] This pressure gradient induces a continuous airflow. Ambient air is drawn into the air turbine 3, then into the siphon 2, following the natural principle of air movement from high-pressure areas to low-pressure areas.

[0072] The air turbine 3, the main element of system 1, exploits the pressure difference between PI and P2 to generate mechanical energy. It converts part of the air pressure energy into kinetic energy, thus functioning as a reverse wind generator where suction replaces wind thrust.

[0073] At the top of the siphon 2, the Venturi effect creates a depression (P3) due to the acceleration of the water 5 in a constricted section. This depression, strong enough to draw in the air exiting the air turbine 3, maintains the airflow throughout the entire system.

[0074] This ingenious system therefore uses the low pressure created by the Venturi effect in the siphon 2 to "pull" air through the air turbine 3, allowing for a continuous generation of mechanical energy without requiring active compression of the air. The air turbine 3 acts as an intermediary, exploiting the pressure difference between the atmosphere and the low pressure point of the siphon 2 to produce useful energy.

[0075] This configuration allows a conversion of hydraulic energy into mechanical energy via an intermediate stage of aeraulic energy, all without external energy input and with optimal compatibility for aquatic biodiversity.

[0076] In one embodiment of the invention, the power generation system 1 comprises an electric generator 4.

[0077] The electric generator 4 is configured to be coupled to the air turbine 3.

[0078] The electric generator 4 is configured to convert the supplied mechanical energy by the air turbine 3 into usable electrical energy.

[0079] The direct coupling between the air turbine 3 and the electric generator 4 ensures a high conversion efficiency.

[0080] However, in some cases, indirect coupling can be achieved by inserting a speed reducer (not shown) between the air turbine 3 and the electric generator 4. Adding a speed reducer makes it possible to adapt the generally high rotational speed of the air turbine 3 to the lower speed required by the electric generator 4. This offers greater flexibility in the choice of components and optimization of their operation. The reducer can also increase the torque transmitted to the electric generator 4.

[0081] The clever arrangement of these different elements (siphon 2 with Venturi effect 8, air introduction device 9, air turbine 3, electric generator 4) allows the energy generation system 1 to efficiently generate electrical energy from a simple liquid flow 5, without any submerged moving part, with a natural ventilation capacity.

[0082] According to an advantageous embodiment, each of the reservoirs 6, 7 can be selected from a watercourse, a water reservoir, a wastewater reservoir, a liquid waste, a waterfall and / or an artificial water reservoir. This allows the energy generation system 1 to be adapted to various situations, environments and installations.

[0083] In a first example, the energy generation system 1 can be installed in natural watercourses. As mentioned above, the upstream reservoir 6 and the downstream reservoir 7 are sections of the watercourse located at different elevations. The siphon 2 connects these two sections, and the air turbine 3 is powered by outside air drawn in by the Venturi effect 8. This first example is advantageous because it uses existing natural resources without requiring the construction of dams, thus reducing environmental impacts.

[0084] In a second example, the energy generation system 1 can be used with wastewater tanks. The upstream tank 6 can be a wastewater collection tank, and the downstream tank 7 can be a treatment tank. The siphon 2 allows the wastewater to be transferred while generating energy. This second example is advantageous for industrial or municipal installations, as it allows wastewater to be recovered by producing renewable energy.

[0085] In a third example, the energy generation system 1 can be integrated into installations with artificial waterfalls. The upstream reservoir 6 is located at the top of the waterfall, and the downstream reservoir 7 at the bottom. The siphon 2 uses the height of the waterfall to maximize the Venturi effect 8 and air intake. This third example is particularly suitable for amusement parks or tourist facilities, providing a source of renewable energy while creating a visual attraction.

[0086] In the fourth example, the energy generation system 1 can be used in industrial cooling systems. The upstream tank 6 can hold hot cooling water, and the downstream tank 7 can hold cooled water. The siphon 2 allows the water to be transferred while simultaneously generating energy and cooling the incoming outside air. This fourth example is advantageous because it combines energy production with cooling, thereby improving the overall energy efficiency of industrial installations.

[0087] In a fifth example, the power generation system 1 can be integrated into a traditional flour mill using hydraulic power. Historically, many watermills were converted into flour mills by replacing the millstones with roller mills, while retaining hydraulic power as the motive force. The mill is supplied with water by a millrace, a diversion channel that brings water to the waterwheel. The upstream reservoir 6 corresponds to the water reservoir upstream of the mill, and the downstream reservoir 7 to the tailrace downstream. The difference in head between the two reservoirs provides the potential energy needed to operate the mill. Energy generation system 1 can be installed in parallel with the existing hydraulic system. Siphon 2 is placed between the millrace and the tailrace, exploiting the difference in elevation. The Venturi effect 8 created by the water passing through siphon 2 draws in air to power an air turbine 3 coupled to an electric generator 4. This fifth example is advantageous because it allows for the production of renewable electricity by utilizing the existing hydraulic infrastructure at the mill, without disrupting the operation of the milling machinery. The generated electricity can be used for the mill's needs or fed back into the grid, providing supplemental income for the miller.

[0088] According to an interesting embodiment, the air turbine 3 can be configured to regulate the flow rate of the liquid 5 flowing in the siphon 2, which is linked to the pressure and flow rate of outside air drawn into the same siphon 2, in coordination with the air introduction device 9. The latter, coupled with the Venturi effect zone 8, allows air to be introduced at a controlled pressure, thus determining the air flow rate Dair and the water flow rate Deau in the siphon 2. The air turbine 3 and the air introduction device 9 therefore work together to optimize the use of the hydraulic energy of the flowing liquid 5, converting it into aerodynamic energy and then into mechanical energy. This provides possibilities for controlling the system to adapt it to variations in flow rate.

[0089] According to another embodiment, the air turbine 3 is configured to regulate the pressure and flow rate of outside air drawn into the siphon 2. This regulation is achieved by exploiting the pressure difference between the atmosphere (PI, approximately 100 kPa) and the point of entry into the siphon (P2, approximately 80 kPa). By modulating its rotational speed or the opening of its blades, the air turbine 3 can directly influence the amount of air it draws in, thus affecting the air flow rate Dair and the water flow rate Deau in the siphon 2. This configuration makes it possible to maintain the pressure and flow rate conditions within an optimal range (between PO-Palt-Pvent and PO-Palt). This allows for fine-tuning of the system's operating conditions, thereby optimizing the exploitation of the hydraulic energy of the flowing liquid 5 and its conversion into mechanical energy.

[0090] In a preferred embodiment, the air turbine 3 is supplied with ambient pressure outside air, which simplifies its integration and makes its operation more reliable under various environmental conditions. By varying the outside air supply, the system can be adjusted for optimal performance without requiring specific pressure or temperature conditions.

[0091] In another preferred embodiment, the air turbine 3 has a power range from 1 kW to 100 kW, allowing flexibility in energy production capacity according to the specific needs of the application. This modularity makes the system adaptable to installations of different sizes and energy requirements.

[0092] In yet another preferred embodiment, the electric generator 4 has a rotational speed of 1500 rpm to 90000 rpm, enabling efficient conversion of mechanical energy into electrical energy. This high-speed capability is particularly beneficial in applications where high electrical power and a rapid response are required.

[0093] Unlike traditional systems, the energy generation system 1 absorbs heat, thus contributing to climate cooling.

[0094] According to a particular embodiment, the power generation system 1 may include variants in the design of the siphon 2, the air introduction device 9, the air turbine 3, and the electric generator 4 to optimize energy efficiency according to the specific conditions of the installation site.

[0095] For example, the siphon 2 can be designed with a length and curvature adjusted to maximize the Venturi effect 8 as a function of the flow rate of the liquid 5 in flow and the difference in altitude between the upstream reservoir 6 and the downstream reservoir 7.

[0096] Furthermore, the siphon 2 can be made from different materials, each offering specific advantages in terms of strength, durability, ease of implementation, and cost. The choice of material depends on the specific constraints of the installation site and the performance objectives of system 1.

[0097] In certain configurations, the siphon 2 is made of wood. Wood offers good mechanical strength, excellent corrosion resistance, and harmonious aesthetic integration into natural environments. Durable, moisture-resistant wood species are preferred to ensure optimal longevity of the structure.

[0098] Alternatively, the siphon 2 can be made of metal, for example stainless steel or aluminum alloy. Metal siphons are characterized by high resistance to mechanical stress, excellent sealing, and long-term durability. They are particularly suitable for installations subjected to intensive operating conditions.

[0099] In other variants, the siphon 2 is made of ceramic. Ceramic offers excellent resistance to abrasion and chemical attack, as well as high dimensional stability. Ceramic siphons are particularly suitable for loaded or corrosive liquids, and offer great ease of maintenance thanks to their smooth and non-porous surface.

[0100] The siphon 2 can also be made of composite material, combining, for example, glass or carbon fibers with a polymer matrix. Composites combine lightness, mechanical strength, and durability, while offering great freedom of shape to adapt to installation constraints. They are particularly well-suited to large-scale systems 1 requiring optimization of the structure's mass.

[0101] Finally, the siphon 2 can be made of plastic, for example PVC, HDPE or PVDF. Plastics offer excellent corrosion resistance, are lightweight, and are easy to manufacture by molding or extrusion. They allow for the creation of complex shapes at a lower cost, while ensuring good sealing and reduced maintenance.

[0102] In an alternative configuration, the siphon 2 may include a first arm 11 extending from the upstream reservoir 6 to the Venturi effect zone 8 and a second arm 12 extending from the Venturi effect zone 8 to the downstream reservoir 7. The first arm 11 rises vertically by a height L (m) from the upstream reservoir 6, while the second arm 12 descends back to the downstream reservoir 7 by a height L+H (m).

[0103] According to another embodiment, the inlet section 111 of the first arm 11 of the siphon 2 has a cross-section between 0.01 m2 and 20 m2. These ranges of values ​​allow the system to function properly for a wide range of applications.

[0104] The term "section" in the context of the invention can refer to the internal surface perpendicular to the fluid flow axis at a given point of the siphon 2. This concept encompasses several types of sections, including the inlet section, the outlet section, and intermediate sections along the path of the siphon 2. In the specific context of the invention, the cross-section is particularly relevant, as it directly determines the flow capacity of the siphon 2, thus influencing the volume of fluid that can pass through the device per unit of time. The cross-sectional area, generally expressed in square meters (m²), is a parameter for characterizing the performance of the siphon 2 in terms of flow rate and fluid transfer efficiency.

[0105] The first arm 11 may have different design variants.

[0106] In a first option, the first arm 11 includes an inlet 111 and an outlet 112, the inlet 111 being configured to be arranged at an altitude strictly lower than the altitude of the outlet 112. More precisely, the inlet 111 can be arranged at the level of the upstream reservoir 6 and the outlet 112 at the level of the Venturi effect zone 8.

[0107] The cross-section of the first arm 11 is continuously reduced from the entrance 111 to the vicinity of the top of the siphon 2. This cross-section can have any shape, by For example, circular or rectangular. The cross-sectional area can vary between inlet 111 and outlet 112. For example, the cross-sectional area of ​​inlet 111 can be larger than that of outlet 112. More precisely, the area of ​​outlet 112 can be between 1 and 5 times smaller than that of inlet 111.

[0108] In one embodiment, the surface area of ​​the outlet 112 of the first arm 11 may be less than the surface area of ​​the inlet 121 of the second arm 12, thus creating the Venturi effect zone 8 at the top of the siphon 2. The outlet 112 section may have a surface area between 0.005 m2 and 15 m2.

[0109] The first arm 11 can also include different types of coatings, selected for example from wood, metal, ceramic, composite or plastic, in order to optimize its mechanical properties and resistance to erosion.

[0110] Finally, in certain configurations, the first arm 11 can be specifically designed to siphon a portion of the liquid 5 flowing from the upstream reservoir 6.

[0111] The second arm 12 of the siphon 2 may also have different design variants.

[0112] In a first option, the section of the second arm 12 can have any shape, for example circular or rectangular, independently of the shape of the section of the first arm 11. The section of the second arm 12 increases continuously from the Venturi effect zone 8 to the outlet 122.

[0113] Alternatively, the second arm 12 may include an inlet 121 and an outlet 122, the inlet 121 being configured to be arranged at an altitude strictly higher than the altitude of the outlet 122. More specifically, the inlet 121 may be arranged at the level of the Venturi effect zone 8 and the outlet 122 at the level of the downstream reservoir 7.

[0114] The cross-section of the second arm 12 can also vary between the inlet 121 and the outlet 122, independently of the surface area variations of the first arm 11. The cross-sectional area increases continuously from the inlet 121 to the outlet 122. For example, the cross-sectional area of ​​the inlet 121 may be smaller than that of the outlet 122. The cross-sectional area of ​​the inlet 121 may have a surface area between 0.005 m² and 20 m², while the cross-sectional area of ​​the outlet 122 may have a surface area between 0.02 m² and 40 m².

[0115] In certain configurations, the section of the outlet 122 of the second arm 12 can be a function of the section of the outlet 112 of the first arm 11, in order to optimize the flow of the liquid 5 in the siphon 2.

[0116] The second arm 12 can also include different types of coatings, selected for example from wood, metal, ceramic, composite or plastic, independently of the coating of the first arm 11, in order to optimize its mechanical properties and resistance to erosion.

[0117] Finally, in certain variants, the second arm 12 can be specifically configured to pump a liquid / air mixture 13 into the downstream reservoir 7, thus improving oxygenation of the moving liquid 5 at the outlet of siphon 2. This configuration is particularly advantageous for the cooling and oxygenation of water reserves or watercourses used for industrial cooling.

[0118] It is important to note that the difference in height H between the upstream reservoir 6 and the downstream reservoir 7 plays an important role in the operation of the siphon 2. This difference in height (and therefore altitude), combined with the continuous reduction of the cross-section of the first arm 11 and the continuous increase of the cross-section of the second arm 12, makes it possible to create the Venturi effect necessary for the suction of air and the operation of the air turbine 3.

[0119] The overall design of the siphon 2, with its variations in cross-section and specific geometry, optimizes the flow of the liquid 5 and the creation of the vacuum necessary for the system to function. This design also contributes to the overall energy efficiency of the system and its ability to generate renewable energy, while offering advantages in terms of water cooling and oxygenation.

[0120] The Venturi effect zone 8 can also have different design and positioning variants.

[0121] In a particular configuration, the Venturi effect zone 8 is arranged at an altitude strictly higher than the altitude of the upstream reservoir 6, in order to optimize the suction effect.

[0122] The section of the Venturi effect zone 8 can have any shape, for example circular or rectangular, independently of the shape of the sections of the arms 11 and 12 of the siphon 2. This section can vary in a range of values ​​from 0.002 m2 to 20 m2, depending on the characteristics of the installation site and the desired performance.

[0123] In some variants, the Venturi effect zone 8 directly includes the air introduction device 9. In other configurations, the Venturi effect zone 8 is fluidly and / or mechanically coupled to the air introduction device 9, the latter being then positioned near said zone.

[0124] The section of the Venturi effect zone 8 can also be determined as a function of the difference in altitude between the altitude of the upstream reservoir 6 and the altitude of said Venturi effect zone 8, in order to optimize the suction effect taking into account the specific geometric characteristics of the installation.

[0125] System 1 may include one or more Venturi effect zones 8, the maximum number being fixed at two in certain variants for reasons of compactness and simplicity. In configurations comprising several Venturi effect zones 8, system 1 may include as many air introduction devices 9 as there are Venturi effect zones 8, each device 9 being associated with a specific zone.

[0126] The flow rate in the first arm 11 of the siphon 2, from the inlet 111 to the outlet 112, can vary over a wide range of values ​​depending on the characteristics of the installation site and the desired performance. In some configurations, this flow rate is between 0.1 m³ / s and 20 m³ / s. This range of values ​​makes it possible to cover a wide variety of applications, from small installations to large-scale systems.

[0127] Similarly, the flow rate of the liquid / air mixture in the second arm 12, from the inlet 121 to the outlet 122, can be adapted to the specific needs of each installation. In some variants, this flow rate ranges from 0.1 m³ / s to 40 m³ / s. This wide range makes it possible to handle large volumes of liquid 5 while ensuring good oxygenation through air entrainment.

[0128] Similarly, the air introduction device 9 may have different design variants to adapt to the specific constraints of each installation of the power generation system 1.

[0129] In certain configurations, the section of the air introduction device 9 can have any shape, for example circular or rectangular, independently of the shape of the sections of the other components of the system 1. The surface area of ​​this section can vary in a range of values ​​from 0.002 m2 to 20 m2, depending on the desired performance and the characteristics of the installation site.

[0130] The air introduction device 9 can be made in various forms, selected for example from a conduit, a pipe, an orifice, a nozzle, a converging nozzle, a jet, or a nozzle. The choice of shape depends on space constraints, permissible pressure losses, and performance objectives.

[0131] In certain variants, the air introduction device 9 is arranged according to the altitude of the downstream reservoir 7, in order to optimize the air intake into the siphon 2, taking into account local pressure conditions. The cross-sectional area of ​​the device 9 can also be determined based on the cross-sectional area of ​​the outlet 112 of the first arm 11, or based on the altitude difference between the upstream reservoir 6 and the Venturi effect zone 8, to adapt the performance of the device to the geometric characteristics of the system 1.

[0132] The air pressure in the air introduction device 9 can vary in a range from -14,000 Pa to -45,500 Pa relative to atmospheric pressure, depending on the intensity of the depression generated in the Venturi effect zone 8. The flow rate of outside air drawn in by the device 9 can be between 0 and 20 m3 / s, and is generally proportional to the suction pressure.

[0133] To optimize suction performance, the air introduction device 9 is preferably coupled to the Venturi effect zone 8 at the point of depression maximum. It is also configured to maximize the equality of the velocity vectors of the liquid 5 and the air, in order to promote momentum exchanges.

[0134] In certain configurations, the air introduction device 9 includes means for regulating the flow of outside air drawn in, for example a regulating valve or a flap register, in order to adjust the performance of the system 1 to the operating conditions.

[0135] Finally, the air introduction device 9 can be made of different materials, for example wood, metal, ceramic, composite or plastic, depending on the mechanical, thermal and chemical constraints specific to each installation, as well as the objectives of durability and cost.

[0136] Similarly, the air turbine 3 can be selected or designed to have a power range adapted to the amount of outside air drawn in by the air introduction device 9, thus allowing optimal conversion of mechanical energy into electrical energy by the electric generator 4.

[0137] The air turbine 3 can be positioned in different ways relative to the level of the liquid 5 flowing in the siphon 2. In practice, it is arranged above this level, in order to limit the risks of immersion and to facilitate maintenance.

[0138] Different types of air turbines 3 can be used in the power generation system 1.

[0139] A particularly advantageous option is to use a variable geometry air turbine 3 at the distributor upstream of the turbine wheel. This technology makes it possible to optimize the performance of the air turbine 3 according to the operating conditions, by adapting the passage cross-section and the angle of attack of the gases.

[0140] Other credible alternatives include double-inlet turbines, impulse turbines, reaction turbines or mixed-flow turbines, each with specific advantages in terms of efficiency, operating range or compactness.

[0141] The rotational speed of the air turbine 3 can be fixed or variable as required. In some variants, the air turbine 3 is configured to operate at variable speed, allowing its power and torque to be adapted to the flow conditions of the liquid 5 and the air. This flexibility is particularly useful for optimizing the system's energy performance over a wide range of flow rates.

[0142] In certain configurations, the air turbine 3 also plays a role in regulating the flow of liquid 5 siphoned by the first arm 11 of the siphon 2. By modulating its rotation speed or its geometry, the air turbine 3 can indeed create a more or less significant back pressure to the suction of the liquid 5, and thus adjust the flow according to the needs.

[0143] The air turbine 3 can be sized for different flow rate ranges, both for the liquid 5 flowing in the siphon 2 and for the outside air drawn in. In some variants, it is configured for liquid flow rates 5 ranging from 0.1 m³ / s to 20 m³ / s, and outside air flow rates drawn in from 0 to 20 m³ / s. These ranges cover a wide spectrum of applications, from small installations to large-scale systems.

[0144] The flow rate of outside air supplying the air turbine 3 can be constant or variable. In certain configurations, it is a function of the rotational speed of the air turbine 3, which makes it possible to adapt the air supply to the actual energy requirements. This regulation can be achieved by mechanical means, such as variable-pitch guide vanes, or by electronic means, such as valves controlled by a controller.

[0145] Finally, to optimize the performance of the air turbine 3, it is preferable to couple it to the air intake device 9 with a sealed duct that minimizes pressure losses. This allows for efficient transfer of energy from the intake outside air, minimizing leakage and heat dissipation.

[0146] The air turbine 3 has specific characteristics which distinguish it from conventional expansion turbines, giving it advantages in terms of cost, durability and manufacturing flexibility.

[0147] First, this air turbine 3 operates with a low expansion ratio, which does not exceed 2 in the most extreme configurations. This characteristic limits the mechanical and thermal stresses on the components, thus paving the way for the use of alternative materials.

[0148] Indeed, thanks to the moderate temperature of the air entering the air turbine 3, it is possible to use low-cost materials for its manufacture, such as certain engineering plastics or organic matrix composites. These materials offer an excellent performance / price ratio for this application, whereas expensive superalloys would be required at higher temperatures.

[0149] This reduced temperature range also has a positive impact on the service life of the air turbine 3. In the absence of significant thermal cycling, fatigue and wear phenomena are greatly reduced. It is therefore possible to achieve exceptional service lives, on the order of 500,000 operating hours, without requiring extensive maintenance. This increased longevity is a major advantage for the reliability and availability of the power generation system 1.

[0150] Finally, the temperature and stress levels compatible with the use of non-metallic materials open up new possibilities in terms of manufacturing processes. In particular, additive manufacturing techniques, such as 3D printing, can be used to produce all or part of the components of the Air turbine 3. Additive manufacturing allows for great design freedom, enabling the integration of complex geometries or optimized cooling channels, for example. It also allows for small production runs at controlled costs, and even for customizing each air turbine 3 to suit local operating conditions.

[0151] Similarly, the power generator 4 can be made according to different technologies, each offering specific advantages in terms of efficiency, compactness and cost.

[0152] A particularly attractive option is to use a permanent magnet generator. This technology offers excellent conversion efficiency thanks to the use of powerful magnets, typically rare-earth (NdFeB), which create an intense magnetic field without excitation losses. Permanent magnet generators are also very compact and lightweight, as they do not require a separate excitation system. They are particularly well-suited to variable-speed applications, such as the air turbine 3 in system 1.

[0153] Alternatively, other types of electric generators 4 may be used, such as wound-rotor synchronous machines, asynchronous machines, or variable reluctance machines. The final choice will depend on the specific constraints of each project, in terms of power, rotational speed, output voltage, and environmental conditions.

[0154] Regardless of the technology used, the electric generator 4 can be configured to be connected to the local or national electrical grid. This connection requires the use of suitable power electronics capable of converting the alternating current produced by the electric generator 4 into a current synchronized with the grid, both in frequency and phase.

[0155] Various power electronics architectures can be considered, such as controlled rectifiers, PWM inverters, or matrix converters. The choice will depend in particular on the power to be injected into the grid, the required power quality, and the applicable connection standards.

[0156] Injection into the network has the advantage of making the best use of the energy produced by system 1, by allowing its consumption by remote users.

[0157] Alternatively, the energy produced by the electric generator 4 can be consumed locally, for example to power electrical equipment located in the immediate vicinity of the system 1. This option is particularly attractive for isolated sites, not connected to the grid, or for applications requiring an autonomous backup power supply.

[0158] The electric generator 4 can be sized to generate different power levels, depending on the specific needs of each installation site of the power generation system 1.

[0159] In certain configurations, the electric generator 4 is designed to produce a relatively modest power output, on the order of 0.5 kW. This power range is particularly suitable for small-scale installations, such as stand-alone systems intended for supplying power to isolated sites or to measurement and communication devices.

[0160] For applications requiring more power, the electric generator 4 can be configured to deliver up to 80 kW. This power range makes it possible to cover a wide spectrum of needs, from powering individual buildings to supplying energy to small communities or medium-sized industrial processes.

[0161] Between these two extremes, the electric generator 4 can be sized to generate any intermediate power output, for example 5 kW, 20 kW or 50 kW, depending on the constraints and objectives specific to each project. This modularity makes it possible to optimize the sizing of system 1 and to adapt it precisely to local energy needs.

[0162] The overall efficiency of the power generation system 1, i.e. the ratio between the electrical energy produced by the electric generator 4 and the hydraulic energy supplied by the flow of the liquid 5, can vary in a range from 25% to 60%.

[0163] In certain optimized configurations, the system 1 can achieve an overall efficiency of 60%. This high performance is achieved through careful design of the entire energy conversion chain, from the Venturi effect zone 8 to the electric generator 4, via the air introduction device 9 and the air turbine 3. An efficiency of 60% means that more than half of the available hydraulic energy is effectively converted into usable electricity.

[0164] In other cases, the overall efficiency of system 1 may be as low as 25%. This lower value can be explained by energy losses related to specific constraints of the installation site, such as a large distance between components or significant pressure losses in the pipes. An efficiency of 25% means that a quarter of the hydraulic energy is ultimately converted into electricity by the electric generator 4.

[0165] Between these two limits, system 1 can exhibit a whole range of intermediate efficiencies, for example 35%, 45% or 55%, depending on its design characteristics and operating conditions. Optimizing overall efficiency is a major challenge for maximizing electricity production from a given hydropower resource.

[0166] Similarly, the power generation system 1 may include electronic control devices to dynamically adjust the operation of the turbine air 3 and the electric generator 4 depending on the variations in the flow rate of the liquid 5 in flow, thus ensuring a constant energy production even in the presence of fluctuations in the supply of water to the upstream reservoir 6.

[0167] These adaptations make it possible to increase the efficiency of the power generation system 1, to reduce energy losses and to optimize electricity production for a wide range of environmental and operational conditions.

[0168] In one embodiment, the power generation system 1 comprises means for measuring the air pressure at the Venturi zone 8 of the siphon 2, means for controlling the flow rate of outside air drawn in by the air turbine 3, including control of the rotational speed of the electric generator 4 coupled to said air turbine 3, and a first control unit. This control unit is configured to automatically control, based on the air pressure measured at the Venturi zone 8, the rotational speed of the electric generator 4 and thus the flow rate of outside air drawn in by the air turbine 3 in order to regulate the flow rate of the liquid 5 flowing in the siphon 2 without human intervention. This allows for automatic and optimized control of the water flow rate in the siphon 2 according to the operating conditions.

[0169] In a first variant of the embodiment, the first control unit of the energy generation system 1 is configured to control the rotational speed of the air turbine 3 and / or the electric generator 4 so as to optimize the operating point of the system at a speed for which there is a reversal between an increase in electrical power generated and a reduction in the flow rate of the liquid 5 flowing in the siphon 2. This makes it possible to maximize the energy efficiency of the system by finding the optimal operating point.

[0170] In a first embodiment, the first control unit of the power generation system 1 is configured to control the rotational speed of the air turbine 3 and / or the electric generator 4 so as to increase the flow rate of the turbined liquid in the siphon 2 with an energy efficiency lower than the maximum efficiency, in order to manage the liquid level in the upstream reservoir 6 during periods of high water, and / or reduce the flow rate of the turbined liquid in the siphon 2 to a predetermined value with an energy efficiency lower than the maximum efficiency, in order to maintain a minimum liquid flow during periods of low water. This makes it possible to significantly broaden the operating range of the system in terms of the flow rate of the liquid 5 compared to operation at maximum energy efficiency, and thus to adapt to seasonal variations.

[0171] In another embodiment, the power generation system 1 includes a level sensor configured to detect when the level of the liquid 5 in The upstream reservoir 6 drops below a predetermined threshold, and a self-priming valve coupled to the siphon 2 and a second control unit activates. This second control unit is configured so that, when the level sensor detects a low level, it triggers the opening of the self-priming valve to induce a controlled depriming of the siphon 2, thus maintaining a minimum flow rate of the liquid 5 towards the downstream reservoir 7. This allows for the automatic management of very low water levels by ensuring a minimum ecological flow rate.

[0172] In yet another embodiment, the air turbine 3 and / or the electric generator 4 are arranged in a de-sealed space, i.e. isolated from the aquatic environment of the siphon 2. This space, isolated from the water, makes it much easier to maintain the air turbine 3 and the electric generator 4 by making them accessible out of the water.

[0173] In one embodiment, the power generation system 1 further comprises at least one air supply duct connecting the Venturi effect zone 8 of the siphon 2 to the air turbine 3 located in the dewatered space. This duct allows the outside air drawn from the air turbine 3 to be conveyed to the siphon 2 while completely isolating the latter from the aquatic environment, thus preventing any risk of contamination.

[0174] The applications of the invention are very diverse. Concrete examples are given below.

[0175] According to a first particular embodiment, the power generation system 1 may include a siphon 2 connecting two freshwater reservoirs, such as a mountain lake and a lowland lake. The difference in altitude between the two lakes is approximately 5 meters, with an average flow rate of 1 m³ / s. The siphon 2 is equipped with a Venturi effect zone 8 located 2 meters below the level of the upstream lake. The inlet section 11 of the siphon 2 has an area of ​​1 m², adapted to the water flow rate. The air turbine 3 used in this case has a power output of 20 kW and is coupled to an electric generator 4 having a rotational speed of 3000 rpm.

[0176] This embodiment is particularly advantageous for mountainous regions with natural lakes at different altitudes. It allows for the production of renewable electricity without impacting water quality and without requiring major infrastructure work.

[0177] According to a second particular embodiment, the energy generation system 1 can also be implemented with artificial water reservoirs, such as retention basins or water towers. In this case, the difference in altitude between the reservoirs can be smaller, on the order of 2 to 3 meters, but the flow rate can be higher, up to 5 m³ / s. A 50 kW air turbine 3 and An electric generator rotating at 6000 rpm can then be used to optimize energy production.

[0178] This embodiment is advantageous for urban or peri-urban areas, where it can be integrated into existing water networks. It offers a decentralized solution for producing electricity close to consumption points, thus reducing line losses.

[0179] These different examples illustrate the flexibility of implementation of the energy generation system 1, which can adapt to various industrial applications and environmental conditions by playing on the choice of tanks, the characteristics of the siphon 2, the adjustment of the air turbine 3 and the sizing of the electric generator 4, while ensuring efficient and ecological energy production.

[0180] Figures 5 and 6 present the results of numerical simulations carried out for an example of sizing of the energy generation system 1 according to the invention.

[0181] The key geometric parameters are a difference in elevation of 1.70 m between the upstream reservoir 6 and the downstream reservoir 7, and a constant cross-section of 6 m2 for the inlets 111 and 121 and the outlets 112 and 122 of the siphon arms 2. The Venturi effect zone 8 is positioned in the liquid vein 5 at a height of 1.2 m above the level of the upstream reservoir 6.

[0182] The simulated operating point corresponds to a liquid flow rate of 3 m³ / s in the siphon 2 and an outside air intake flow rate of 2.1 m³ / s at the air inlet device 9. The negative pressure generated by the Venturi effect at the intake point reaches -20 kPa relative, corresponding to an absolute pressure of 0.8 bar. Under these conditions, the mechanical power extracted at the shaft of the air turbine 3 amounts to 21 kW, for a mechanical efficiency of converting hydraulic energy into mechanical energy of 0.45.

[0183] The graphical representations in Figures 5 and 6 illustrate the liquid velocity ('velocity magnitude'), static pressure ('static pressure'), and air volume fraction ('volume fraction') profiles corresponding to this operating point. In particular, they show the acceleration of the liquid 5 in the Venturi effect zone 8, the static pressure drop at the suction point of the device 9, and the entrainment of air in the liquid stream 5 downstream of the Venturi effect zone 8.

[0184] These simulation results demonstrate the ability of the energy generation system 1 to produce significant mechanical power from the gravitational flow of a liquid, by efficiently exploiting the Venturi effect to draw in air and drive an air turbine 3. They thus validate the concept of the invention and allow the design parameters to be optimized according to the installation conditions and the performance objectives.

[0185] According to another aspect, the invention relates to a method 100 for producing electrical energy from the potential energy of a liquid 5.

[0186] The energy production process 100 may include a step of circulating 110 the liquid 5 between the upstream reservoir 6 and the downstream reservoir 7 via the siphon 2.

[0187] The energy production process 100 may further include a step of accelerating the flow of the liquid 5 in the Venturi effect zone 8 of the siphon 2, so as to create a localized depression which allows the aspiration of air via an air introduction device 9, thus converting the hydraulic energy of said liquid 5 in flow into aerodynamic energy.

[0188] Next, the energy production process 100 may include a transfer step 130 of ambient air to an air turbine 3 disposed outside said siphon 2, and then the introduction of this air, after its passage through the air turbine 3, into the siphon 2 via said air introduction device 9 coupled to said air turbine 3.

[0189] Finally, the energy production process 100 may include a stage of expansion 130 of the outside air drawn into the air turbine 3 coupled to the air introduction device 9, the air turbine 3 converting the kinetic energy of the air into mechanical energy.

[0190] In a particular embodiment, the energy production process 100 may include a step of converting mechanical energy into electrical energy via an electric generator 4 coupled to the air turbine 3, the electricity produced then being able to be injected into the network or stored locally.

[0191] The energy production process 100 enables efficient implementation of the energy generation system 1 in an environmentally friendly manner, optimizing the use of hydraulic energy and minimizing environmental impacts.

[0192] In addition, the use of the energy generation system 1 according to the invention for this energy production process 100 has several advantages.

[0193] First, the absence of moving parts in the flowing liquid 5 simplifies installation, reduces maintenance costs, and ensures optimal protection of aquatic fauna. Indeed, this system is inherently fish-friendly, meaning it minimizes the risk of injury or death to fish as they pass through the installation. This characteristic is particularly important for the preservation of migratory species and aquatic biodiversity.

[0194] In addition, the regulation of the air flow and pressure by the air turbine 3 makes it possible to optimize the energy efficiency of the system.

[0195] In the invention, system 1 uses a quasi-adiabatic expansion to cool the air and reduce its pressure. Indeed, when outside air passes through the air turbine 3 To supply the Venturi zone 8 via the air inlet device 9, the air undergoes a quasi-adiabatic expansion. This process simultaneously cools the air and reduces its pressure. In this system 1, depending on the design, the expansion ratio (defined as the ratio between the pressure in the Venturi zone 8 and atmospheric pressure) varies between 0.8 and 0.5. This expansion causes the air to cool by between 15 and 40 degrees Celsius, respectively. The expansion ratio, and consequently the air cooling, is determined by two main factors: the difference in altitude between the upstream reservoir 6 and the Venturi zone 8 where the depressurized air is introduced, and the reduction in the cross-sectional area of ​​the liquid 5 in the Venturi zone 8. The air flow rate undergoing this temperature reduction is directly related to the water flow rate drawn from the upstream reservoir 6.Optimizing the geometric design of siphon 2 allows for balancing the volumes of air and liquid 5 passing through siphon 2, thus ensuring efficient system operation.

[0196] System 1 can be adapted to neutralize the climate impact of a site while generating renewable energy. Indeed, a site contributing to global warming through heat release could, if it has a suitable hydraulic environment, install System 1. By adapting the design of System 1 in terms of flow rate and negative pressure, and therefore the flow rate of cooled air, the site could neutralize its impact on global warming while benefiting from a renewable source of electrical energy for its operation. This System 1 eliminates the need for energy-intensive ventilation, as the air heated by the installations would be naturally drawn in, thus canceling the thermal impact. Moreover, the principle is particularly efficient, as the efficiency of the air turbine 3 improves with increasing incoming air temperature, for a constant design.

[0197] System 1 offers promising applications for data centers and hydrogen production facilities, among others. Indeed, installing System 1 on a site can primarily aim for climate neutrality while providing a renewable energy source. This system is particularly relevant for facilities such as data centers, whose numbers are increasing with the development of Artificial Intelligence and which contribute significantly to global warming. It can also be applied to hydrogen production facilities using electrolysis, which, even when powered by renewable energy, generate heat equivalent in power to the hydrogen produced, with an overall efficiency of less than 50%.

[0198] System 1 can be optimized for the efficient cooling of water reservoirs and watercourses. Indeed, system 1 can also be designed primarily to cool a water reservoir or a watercourse (downstream reservoir 7). To optimize this effect, the second arm 12 must be sufficiently extended in the downstream reservoir 7. This maximizes heat exchange between the cooled air and the surrounding liquid, allowing for optimal cooling of the water before the air rises to the surface. This application is particularly relevant for the many industrial sites that use watercourses for cooling and face limitations due to high temperatures, exacerbated by climate change or growth ambitions. System 1 could solve this problem, especially since these facilities often already have penstocks leading to the watercourse, thus facilitating system implementation without major investments.

[0199] In one embodiment, the energy production process includes a step of automatic control and servo control of the flow rate of outside air drawn in by the air turbine 3 as a function of a measurement of the air pressure at the level of the Venturi effect zone 8. This control is carried out via a control of the rotation speed of the electric generator 4 coupled to the air turbine 3. This makes it possible to regulate precisely and automatically the flow rate of the liquid 5 flowing in the siphon 2 without requiring human intervention, by adapting in real time the flow rate of outside air drawn in to the operating conditions.

[0200] In another embodiment, the energy production process comprises the following steps: - To detect, using a level sensor, when the level of liquid 5 in the upstream reservoir 6 falls below a predetermined threshold, - In response to this detection, trigger the opening of a self-priming valve connected to siphon 2 to induce a controlled depriming of said siphon 2, and - Regulate the flow rate of outside air drawn in by the air turbine 3 to maintain a minimum flow rate of liquid 5 from the upstream tank 6 to the downstream tank 7 after said depriming. These steps allow for the automatic management of very low water levels in the upstream tank 6, by inducing a controlled depriming of siphon 2 while maintaining a minimum ecological flow rate downstream, without risking damage to the installations.

[0201] The invention described and claimed lies in the use of the Venturi effect to draw in air without an additional pump, and in the expansion of this air by the air turbine 3 to produce mechanical energy.

[0202] Unlike traditional energy generation systems that generate heat, this system absorbs heat by drawing in and cooling air. This characteristic gives it a heat absorption capacity at least equivalent to the electrical power it generates. Furthermore, system 1 offers operational flexibility, allowing optimization of either cooling, by maximizing the flow rate of outside air drawn in and cooled, or energy generation efficiency, depending on the specific application requirements.

[0203] Furthermore, the system has no moving parts in the flowing liquid 5, which reduces maintenance costs and increases reliability. Other envisaged advantages are installation flexibility in various hydraulic environments, the ability to regulate flow and pressure, and a wide range of rotational speeds for the electric generator 4.

[0204] This innovative system opens up interesting prospects for various industrial applications requiring a clean and efficient energy source, such as electricity generation from rivers, water reservoirs, or wastewater. It could also be used to power signaling buoys or marine water treatment plants.

[0205] In summary, this invention provides a promising solution to the challenges of energy efficiency and environmental impact in the field of hydropower production, by innovatively exploiting the principles of the Venturi effect and air expansion.

[0206] The invention can be the subject of numerous variations and applications other than those described above. In particular, unless otherwise indicated, the various structural and functional features of each of the embodiments described above should not be considered as combined and / or closely and / or inextricably linked to one another, but rather as mere juxtapositions. Furthermore, the structural and / or functional features of the various embodiments described above may be the subject, in whole or in part, of any different juxtaposition or any different combination.

Claims

Demands

1. A power generation system (1) configured to exploit the flow of a liquid (5) to generate usable mechanical energy, without external energy input, the power generation system (1) comprising a siphon (2), an air inlet device (9), and an air turbine (3): - the siphon (2) being configured to connect the flowing liquid (5) from an upstream reservoir (6) to a downstream reservoir (7), the upstream reservoir (6) and the downstream reservoir (7) being located at different altitudes, said siphon (2) further being provided with a constriction forming a Venturi effect zone (8) where the flow of the liquid (5) is accelerated and the pressure is reduced according to Bernoulli's equation, thus converting the hydraulic energy of said flowing liquid (5) into aerodynamic energy by drawing in outside air, - the air inlet device (9) being coupled to the Venturi effect zone (8) and to the air turbine (3),the air inlet device (9) being configured to create an intake of outside air, via the air turbine (3), by the depression generated in said Venturi effect zone (8) and to transfer the aerodynamic energy thus obtained to the siphon (2), and - the air turbine (3) being disposed outside said siphon (2) and configured to be supplied with outside air and to supply said siphon (2) via the air inlet device (9), said air turbine (3) being further configured to expand the intake outside air and convert said aerodynamic energy into mechanical energy.

2. Power generation system (1) according to claim 1 further comprising an electric generator (4) configured to be coupled to the air turbine (3) and to generate electrical power from mechanical energy.

3. Energy generation system (1) according to any one of claims 1 to 2, characterized in that it further comprises: - means for measuring air pressure at the level of the Venturi effect zone (8) of the siphon (2), - means for controlling the flow of outside air drawn in by the air turbine (3), including control of the rotation speed of the electric generator (4) coupled to said air turbine (3), and - a first control unit configured to automatically control, as a function of the air pressure measured at the level of the Venturi effect zone (8), the rotation speed of the electric generator (4) and therefore the flow of outside air drawn in by the air turbine (3) so as to regulate the flow of the liquid (5) flowing in the siphon (2) without human intervention.

4. Power generation system (1) according to claim 3, characterized in that the first control unit is configured to drive the rotational speed of the air turbine (3) and / or the electric generator (4) so ​​as to optimize the operating point of the system (1) at a speed for which there is a reversal between increasing electrical power generated and reducing the flow rate of the liquid (5) flowing in the siphon (2).

5. Power generation system (1) according to any one of claims 3 to 4, characterized in that the first control unit is configured to drive the rotational speed of the air turbine (3) and / or the electric generator (4) so ​​as to: - increase the flow rate of the liquid (5) turbined in the siphon (2) with an energy efficiency lower than the maximum efficiency, in order to manage the level of the liquid (5) in the upstream reservoir (6) during flood periods, and / or - reduce the flow rate of the liquid (5) turbined in the siphon (2) to a predetermined value with an energy efficiency lower than the maximum efficiency, in order to maintain a minimum flow of the liquid (5) during low-water periods, thus widening the range of use of the system (1) in terms of the flow rate of the liquid (5) in flow compared to operation at maximum energy efficiency.

6. A power generation system (1) according to any one of claims 1 to 5, characterized in that it comprises: - a level sensor configured to detect when the level of the liquid (5) in the upstream reservoir (6) falls below a predetermined threshold, and - a self-priming valve coupled to the siphon (2) and a second control unit, said second control unit being configured to, when the level sensor detects a low level, command the opening of the self-priming valve in order to cause a controlled priming of the siphon (2) allowing to maintain a minimum flow of said liquid (5) flowing towards the downstream reservoir (7).

7. Power generation system (1) according to any one of claims 1 to 6, characterized in that the air turbine (3) and / or the electric generator (4) are arranged in a de-sealed space isolated from the aquatic environment of the siphon (2), said de-sealed space enabling the maintenance of said air turbine (3) and electric generator (4) to be facilitated.

8. Power generation system (1) according to any one of claims 1 to 7, characterized in that the air turbine (3) is configured to exploit a pressure difference between the ambient air PI and the expanded air P2 at the outlet of the air turbine (3), said pressure difference being created by the Venturi effect in the siphon (2), such that the ratio between the cooling power of the aspirated air and the mechanical power produced by the turbine (3) is greater than or equal to 1.

9. System (1) according to any one of claims 1 to 8, characterized in that it further comprises a control device configured to adjust the air flow rate Dair and the water flow rate Deau in the siphon (2) as a function of the temperature of the air or the liquid to be cooled, said control device being coupled to the air introduction device (9) and to the air turbine (3) to regulate the air introduction pressure in the siphon (2).

10. System (1) according to claim 9, characterized in that the control device is configured to maintain the air introduction pressure in the siphon (2) between PO-Palt-Pvent and P0-Palt, where PO is atmospheric pressure, P0 is the pressure due to altitude, and Pvent is the pressure due to the Venturi effect, so as to simultaneously optimize the production of mechanical energy and the cooling of the air or liquid.

11. A system (1) according to any one of claims 1 to 10, characterized in that a second arm (12) of the siphon (2) is configured to extend into the downstream reservoir (7) over a length sufficient to maximize heat exchange between the cooled air circulating in said second arm (12) and the surrounding liquid, said second arm (12) comprising a heat exchange wall designed to promote heat transfer between the cooled air and the liquid in the downstream reservoir (7), thus allowing the cooling of said liquid before the air rises to the surface.

12. Flour mill comprising: - a mill configured to grind cereal grains and produce flour, - a power generation system (1) according to any one of claims 1 to 11, wherein: — the upstream reservoir (6) corresponds to a water reservoir upstream of the mill, — the downstream reservoir (7) corresponds to a tailrace channel downstream of the mill, — the siphon (2) is placed between a millrace supplying water to the mill and the tailrace, exploiting a difference in altitude between the upstream (6) and downstream (7) reservoirs, — the air turbine (3) is coupled to an electric generator (4) configured to produce electricity from the mechanical energy generated by the expansion of air in the air turbine (3), and — electrical connection means configured to supply at least some of the electricity produced by the electric generator (4) to milling equipment and / or to inject said electricity into an external electrical network.

13. A method (100) for producing energy from the potential energy of a liquid (5), comprising - An acceleration step (120) of the flow of the liquid (5) in a Venturi effect zone (8) of a siphon (2) connecting an upstream reservoir (6) to a downstream reservoir (7), the upstream reservoir (6) and the downstream reservoir (7) being located at different altitudes, so as to create a localized depression which allows the aspiration of outside air via an air introduction device (9) coupled to said Venturi effect zone (8), thus converting the hydraulic energy of said liquid (5) in flow into aerodynamic energy, - A transfer step (130) of ambient air to an air turbine (3) disposed outside said siphon (2), then the introduction of this air, after its passage through the air turbine (3), into the siphon (2) via said air introduction device (9) coupled to said air turbine (3), and - A stage of expansion (150) of the outside air drawn into the air turbine (3), the air turbine (3) converting the aerodynamic energy into mechanical energy, the process (100) being implemented without external energy input.

14. Method (100) of energy production according to claim 13, characterized in that it further comprises a step of automatic control and servo control of the flow of outside air drawn in by the air turbine (3) via a control of the rotation speed of the electric generator (4) coupled to said air turbine (3), as a function of a measurement of the air pressure at the level of the Venturi effect zone (8), so as to regulate the flow of the liquid (5) flowing in the siphon (2) without human intervention.

15. A method (100) for producing energy according to any one of claims 13 to 14, characterized in that it comprises the following steps: - detecting, by means of a level sensor, when the level of the liquid (5) in the upstream reservoir (6) falls below a predetermined threshold, - in response to said detection, controlling the opening of a self-priming valve coupled to the siphon (2) in order to cause a controlled priming of said siphon (2), - regulating the flow of outside air drawn in by the air turbine (3) so as to maintain a minimum flow of said liquid (5) flowing from the upstream reservoir (6) to the downstream reservoir (7) after said priming.

Images