Wind turbine based on Bernoulli's principle of negative pressure

Abstract

Wind power plant comprising a tower with at least 2 openings for air, a duct system, a turbine (11) in the intake duct, connected to a generator (4) for generating electrical energy, wherein the tower consists of a wing-like profile, the air flowing past it creates a negative pressure on the outwardly (convexly) curved side, characterized in that a flap (13) is located at the upper end of the tower, which is closed in negative pressure operation and can be opened to control the chimney effect and, in low wind or calm conditions, drives the generator (4) and generates energy through the upward flow of air.

Description

[0001] The invention relates to a wind turbine for generating electricity by utilizing the negative pressure (according to Bernoulli) that arises with a wing-like profile (1) and the chimney effect that arises with such towers. State of the art

[0002] Currently, electricity from wind power is predominantly generated by wind turbines with rotor blades or paddles. These are mounted on a mast or tower. The rotor axis can be slightly inclined to the horizontal or horizontally oriented (HAWT = horizontal axis wind turbine), or it can coincide with or be parallel to the mast or tower axis (VAWT = vertical axis wind turbine). The rotor is driven by wind, and the rotational motion is transferred to an electric generator.

[0003] This operating principle produces a so-called whining sound or whooshing noise and casts strobe-like shadows due to the rotating rotor blades. Both the noise and the shadows are perceived as unpleasant by people, which is why a minimum distance to residential areas must be maintained.

[0004] Furthermore, the high speed of the rotor blades poses a danger to native birds, bats, and migratory birds. Therefore, numerous environmental and nature conservation regulations must be observed during the permitting process. Due to these characteristics, potential installation sites are significantly reduced, and the permitting procedures can take up to seven years. The following patents relating to the state of the art were considered: WO 2016 / 054 080 A1 Publication date: 07.04.2016 WO 2023 / 195854A1 Publication date: 12.10.2023 DE 10 2014 014 199 A1 2016.03.17 Publication date: 17.03.2016 DE 10 2016 006 702 A1 2017.05.11 Disclosure date: 11.05.2017 DE 10 2018 127 869 A1 2019.12.05 Disclosure date: 05.12.2019 DE 10 2020 006 586 A1 2021.02.18 Disclosure date: 18.02.2021

[0005] Known wind power plants utilize rotor blades or vanes mounted on a mast or tower. The rotor is driven by wind, and the rotational motion is transferred to a power generator. German patent application DE 10 2014 014 199 A1 (17.03.2016) proposes increasing wind loads by utilizing the chimney effect through air inlet and outlet openings. In contrast, German patent application DE 10 2020 006 586 A1 (18.02.2021) utilizes the differential pressure created in towers / tubes due to the height difference to drive a turbine wheel.

[0006] Further concepts were also found that are part of the state of the art, such as... 1. vertical wind turbine 2. Exploitation of the Venturi effect (Sheerwind) (2014) 3. Utilizing the chimney effect

[0007] However, these concepts have not yet been able to prevail or make a decisive contribution to energy production. Description

[0008] The invention relates to a novel wind turbine for generating electricity by utilizing the negative pressure (according to Bernoulli) created by a wing-like profile (1). This negative pressure draws air in through openings in the tower and an associated duct system (3). A turbine (11) is located in the intake duct, driven by the flowing air and connected to one or two generators (4).

[0009] Additionally, at the top of the tower there is a flap (13) which is closed in negative pressure operation and can be opened to control the chimney effect and, in low wind or calm conditions, drives the generator (4) by the upward flow of air and generates energy.

[0010] The wing-like profile is connected to the stationary lower part by a rotating ring (6) and can always be optimally aligned with the wind or sun. This is accomplished either electrically or via a wind vane.

[0011] The main advantage of this novel wind turbine compared to a rotor-based system is likely to be its ease of approval by authorities, acceptance by environmental organizations and the public, as its wing-like profile blends into the landscape more harmoniously than towers with rotors. Furthermore, the system is characterized by significantly lower noise pollution and poses no danger to birds or bats, so little or no resistance from authorities, citizens, and environmental and nature conservation associations is expected.

[0012] Another advantage is the simpler design. There is no need for the complex assembly of generators or rotors using a crane or helicopter. The generator is preferably located near the ground. The intake (5) is positioned at a height where it poses no danger to people or animals. A sufficiently large, funnel-shaped opening in the intake (5) reduces the wind speed to such an extent that there is no risk to people or animals. This design also reduces construction and maintenance costs compared to systems with rotor blades.

[0013] The second stage of development includes the use of photovoltaics (10) on the flat side of the profile, which is usually oriented to the south due to the prevailing wind direction in Western Europe from west to east. Task:

[0014] The object of the present invention is to generate energy without the disadvantages of wind turbines with rotor blades and to enable a faster expansion of wind power. Solution to the problem:

[0015] By utilizing the negative pressure that arises according to Bernoulli's equation for dynamic and static pressure when the dynamic pressure is greater than the static pressure, and by utilizing the chimney effect that occurs in such towers.

[0016] If you create a wing-like profile with openings at its thickest / most pronounced camber (i.e., where the greatest low pressure is created), position it vertically, and align it with the wind direction, the airflow at that point will create a low pressure. This low pressure will draw air out of the holes in the profile. (Other geometries with wing-like profiles are also possible, e.g., additional horizontal profiles with holes alongside the vertical profile.)

[0017] Either the profile (1) itself is used as the intake duct, or a tube system (3) inside it. This tube system can be fitted with flaps to optimize the system's efficiency. Air is drawn in at the lower end of the profile and drives one or two generators via a turbine (11) in the intake airflow. The generator is located outside the duct to minimize flow resistance. It is either directly below the tower with a shaft to the generator or connected laterally to the intake duct via a belt drive.

[0018] To achieve the optimal angle of attack relative to the wind direction, the tower is adjusted either mechanically with a weather vane or electrically via a rotating ring. The rotating part of the tower is connected to the stationary part of the system by a pipe (8).

[0019] The airflow on the surface of the profile can be optimized with riblets (shark skin). This is achieved either by applying appropriately ribbed riblet films, by painting (with the structure embossed before curing with UV light), or by directly lasering the surface.

[0020] Ideally, the system would be coupled with a storage facility for the generated energy. A hydrogen production device with a storage unit would be suitable for this purpose. Since this is currently still relatively expensive, using used batteries from electric cars as storage is a viable alternative (this naturally depends on the system's output).

[0021] This invention could produce electricity in windy conditions (low pressure), sunny conditions (photovoltaics), and when there is no wind or at night (chimney effect).

[0022] The advantages of this invention would make a significant contribution to independence from fossil fuels. Furthermore, rapid expansion is possible, as widespread acceptance among citizens, environmentalists, and conservationists is expected, allowing for the use of previously unsuitable areas. Additionally, native birds / bats and migratory birds would be protected.

[0023] In calm or low wind conditions, the chimney effect created by such towers is used for additional energy generation. For this purpose, a flap (13) is located at the top of the tower. This flap is closed during negative pressure operation.

[0024] If the temperature inside the profile is warmer than the outside temperature, a chimney effect occurs. This effect is due to the fact that warm air has a lower density than cold air, resulting in thermal convection. In this operating mode, the air exits through the upper flap (13). A negative pressure is created inside the tower, drawing air in through the intake duct. This duct contains a turbine (11) that drives one or two generators. Therefore, this system can still generate electricity even in light winds or calm conditions.

[0025] The chimney effect is used in the Persian wind tower, called Bagdir, to cool houses.

[0026] To initiate and enhance this effect, the tower can be painted dark and heating elements can be installed inside the tower, powered by rechargeable electrical storage, photovoltaics or ongoing electricity production.

[0027] Alternatively, the lower part of the tower or the roof of the operations building can be fitted with solar collectors. These collectors absorb solar heat. A water-antifreeze mixture transfers this heat via a heat exchanger to the solar storage tank. This tank supplies heating elements inside the tower and initiates and enhances the chimney effect. First expansion stage:

[0028] Furthermore, the wind turbine can be combined with a photovoltaic system (10). In this case, the surface of the profile opposite the curved side is fitted with solar cells.

[0029] Since a west-east wind usually blows in large parts of Europe, and thus the tower with the curved side of the profile points towards the north, the surface opposite the curved side, which is equipped with solar cells, is automatically oriented towards the south.

[0030] Depending on where the greatest efficiency is achieved, wind or solar, the profile could be tracked via the rotating ring (6) to follow the sun and the system could always be operated with the optimal efficiency. Construction type: Tower

[0031] A shell construction using particle- or fiber-reinforced polymers, steel, or concrete could be suitable here; organic materials (wood / bamboo) are also conceivable. This depends on the size of the plant. A combination of these materials is also possible. Operations building (12) / Switchgear

[0032] The switchgear (9) is located at ground level in the operations building and is therefore easily accessible. The generator and air intake are preferably located on the first floor and are thus also easily accessible. The intake at this height poses no danger to humans or animals.

[0033] By appropriately designing the building (e.g., cladding it with wood), the facility blends better into the environment and increases acceptance. Reference symbol list (Fig. 1-4): 1 profile (wing-like) 2 openings 3 pipe system 4 Generator 5 Intake 6 Turntable 7 Fixed pipe 8 pipes in a rotating tower 9 Switchgear 10 Photovoltaics 11 Turbine / Fan blades 12 company buildings 13 Air flap 14 solar collectors Four pages of drawings follow. Fig. 1 Complete system, tower with air inlet and outlet openings Fig. 2 Section of the tower in the area of ​​the air outlet openings Fig. 3. Tower top with opening flap Fig. 4 Intake with turbine, generator and tower slewing ring, solar collectors

Claims

[1] Wind turbine consisting of a tower with at least two openings for air, a duct system, a turbine (11) in the intake duct, connected to a generator (4) for generating electrical energy, wherein the tower consists of a wing-like profile, the passing air creates a negative pressure on the outwardly (convex) curved side, characterized by that at the top of the tower there is a flap (13) which is closed in negative pressure operation and can be opened to control the chimney effect and, when there is little wind or no wind, drives the generator (4) and generates energy through the air flowing upwards. [2] Wind turbine according to claim 1, characterized by that additional photovoltaics (10) are used by equipping the surface of the profile opposite the curved side with solar cells (10). [3] Wind turbine according to claim 1 or 2, characterized byThe profile can be aligned using a rotating ring (6). Depending on where the greatest efficiency is achieved, wind or solar, the profile can be adjusted using the rotating ring (6), allowing the system to always operate at optimal efficiency. [4] Wind turbine according to claim 1, characterized by that the chimney effect is initiated or enhanced by dark painting of the tower and / or by heating elements supplied with hot water from solar collectors or electrical storage tanks.

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