Vertical-axis double-turbine tidal energy (reverse power) power generation device and efficient working method

Abstract

A vertical-axis double-turbine tidal energy (reverse power) power generation device and an efficient working method are characterized in that a primary turbine and a secondary turbine are adopted for the first time, and the primary turbine starts the secondary turbine through natural hydraulic power; the secondary turbine drives the generator to generate power by using relative hydraulic power, and the relative attack angles of all blades of the secondary turbine at any position are equal to 0 degree because the directions of the relative hydraulic power are opposite, so that all the blades can synchronously output power at any position; in this way, the problem that blades of an existing vertical shaft turbine cannot synchronously output force is solved. The blades of the primary turbine or the secondary turbine are connected with the hub in the horizontal direction, and therefore the problem that the diameter of an existing vertical shaft turbine cannot be enlarged is solved. A brand-new salix leaf type reverse power blade is adopted for a primary turbine or a secondary turbine, the cross section structure of the blade is in a salix leaf type, namely, the upper arc face and the lower arc face are completely symmetrical, and the efficient working method of the blade is that the blade is kept in a completely horizontal working state, namely, the zero lift angle and the relative attack angle are both zero. As a result, the rotating resistance is parallel to the chord line, so that the rotating resistance and the blade tail eddy current loss are extremely small, the laminar flow boundary layer is relatively stable, and the reverse power efficiency is relatively high.

Description

[0001] Technical Field: The present invention relates to the technical field of hydropower generation.

[0002] Background Art: Tidal energy is formed by the universal gravitation of the moon-earth coupling. As long as the moon and the earth remain unchanged, tidal energy will remain unchanged cyclically. Therefore, tidal energy is a pure green renewable energy with extremely good stability. In addition, the density of tidal energy is much larger than that of wind energy. Because the density of water is generally ρ = 1000 kg / , while the density of air is generally only ρ = 1.2 kg / . We know that the natural wind speed in nature is generally only U = 6 - 10 m / s, while the flow velocity of tidal water is generally only U = 3 - 4 m / s. Let the area A = 1 , then the natural wind energy = ρ • A • = • 1.2 • A • = 600 W, while the tidal energy = = • 1000 • A • = 32000 W. Therefore, the density of tidal energy is 53 times that of natural wind energy. In addition, the directions of the flood tide and the ebb tide of tidal energy are opposite.

[0003] Existing tidal energy turbines are mainly horizontal-axis wing-type turbines, and the horizontal-axis wing-type turbines have the following advantages: that is, the rotation plane of the horizontal-axis wing-type turbine is perpendicular to the water flow direction. Therefore, the natural angle of attack of all blades of this turbine is the same at any position. Therefore, all blades of this turbine can output power synchronously. Therefore, the efficiency of this turbine is relatively high.

[0004] The horizontal-axis airfoil turbine has the following disadvantages: (1). Since the shape of the existing horizontal-axis airfoil turbine is like a spoke: the blades extend outward from the hub like the spokes of a bicycle wheel, and the maximum number of blades does not exceed three. The biggest disadvantage of such a spoke structure is that the solidity is too small, resulting in a very low capture rate of natural water energy (the solidity of the existing horizontal-axis airfoil wind turbine is only 0.03, which means that 97% of the natural wind energy is wasted). (2). Since all the blades of the existing horizontal-axis airfoil wind turbine are airfoil lift blades, the cross-sectional structure of the blade is asymmetric, and the operating state parameters such as pitch angle, zero-lift angle, and natural angle of attack are all greater than 0°. As a result, the rotational resistance angle is also greater than 0°, which leads to the intersection of the rotational resistance and the chord line, and the rotational resistance is relatively large. This will undoubtedly hinder the rotation of the blade, thereby reducing the efficiency of the blade. (3). The diameter of the horizontal-axis turbine is limited by the water depth, and the diameter of the turbine directly determines the size of its rated capacity. (4). The generator of the horizontal-axis hydraulic turbine is immersed in water for a long time, not only has the risk of leakage, but also has a relatively high maintenance cost.

[0005] The greatest advantage of the vertical-axis turbine is that it can accept water flows from any direction, which is crucial for the utilization of tidal energy.

[0006] The disadvantages of the vertical-axis airfoil turbine are also obvious: (1). The rotary surface of the vertical-axis airfoil turbine is parallel to the flow direction, resulting in the continuous change of the natural angle of attack of all the blades of the turbine. As we know, only when the angle of attack is equal to 15°, the lift coefficient can reach the maximum value of 1.2 - 1.5, and the blade can have an angle of attack equal to 15° only when it is in a specific position. Once it leaves the specific position, the lift coefficient of the blade will drop significantly until it becomes zero. This is one of the reasons for the low efficiency of the existing vertical-axis airfoil turbine. (2). When the lift coefficient of the blade of the vertical-axis airfoil turbine is the largest, the rotational resistance is also the largest. This is the second reason for the low efficiency of the vertical-axis hydraulic turbine. (3). The blades of the vertical-axis turbine are installed vertically. The blade is not the power arm, but the support rod is the power arm. And the support rod has to bear the weight of the blade, so the support rod cannot be extended. Therefore, the turbine diameter cannot be enlarged. Therefore, the rated power of the vertical-axis turbine is relatively small.

[0007] In summary, existing horizontal-axis turbines have high efficiency, but the turbine diameter is limited by water depth and cannot be enlarged. Moreover, the turbine needs to be aligned with the water flow direction. Once it deviates, the efficiency will drop to zero, while the flood tide and ebb tide of the tide are in opposite directions. Existing vertical-axis turbines do not need to be aligned with the water flow direction, but the efficiency of existing vertical-axis turbines is low, the turbine diameter cannot be enlarged, and the rated power is too small. The present invention proposes a vertical-axis dual-turbine tidal energy (reaction power) generation device and an efficient working method. This device has all the advantages of the above-mentioned horizontal-axis turbines and vertical-axis turbines: it can be enlarged, has high efficiency, and does not require yaw and can utilize water energy in any direction.

[0008] Summary of the Invention: This application is a divisional application of an invention submitted by the applicant on March 1, 2025, namely: a vertical-axis dual-rotor wind power (reaction power) generation device and an efficient working method, with the application number: 2025102371362.

[0009] When the inventor was conducting wind tunnel tests on blades of various structural forms, it was accidentally found that a vertical-axis willow-leaf-shaped blade has a phenomenon of rotating against the wind. The specification appendix Figure 1 gives a schematic diagram of the vertical-axis willow-leaf-shaped blade rotating against the wind. As shown in this figure, the willow-leaf-shaped blade (1) rotates against the wind around the vertical axis (2). The specification appendix Figure 2 gives the A-A cross-sectional view in the above Figure 1 . As shown in this figure, the cross-sectional structure of the willow-leaf-shaped blade (1) is willow-leaf-shaped, that is, the upper and lower arc surfaces are completely symmetrical, and the camber h and thickness b are both within appropriate ranges. The efficient working method of this blade is: maintaining a completely horizontal working state, that is, both the zero-lift angle and the angle of attack are zero.

[0010] The specification appendix Figure 3 gives the cross-sectional structure and lift working principle diagram of a general airfoil lift blade. As shown in this figure, the cross-sectional structure of a general airfoil blade is airfoil-shaped, that is, the upper and lower arc surfaces are asymmetrical, and the camber h and thickness b are both within appropriate ranges. The working state parameters of the zero-lift angle and the angle of attack α are both greater than zero. Only in this way can the airfoil blade form lift . However, the cross-sectional structure of the above willow-leaf-shaped blade (1) is willow-leaf-shaped, that is, the upper and lower arc surfaces are completely symmetrical. The working state parameters of this blade, the zero-lift angle and the angle of attack, are both equal to zero. Therefore, no lift can be formed on the upper surface of the willow-leaf-shaped blade (1). So, the power that drives the willow-leaf-shaped blade (1) to rotate against the wind is not lift. Then, where does the power that drives the willow-leaf-shaped blade (1) to rotate against the wind come from?

[0011] The inventor believes that the laminar boundary layer is the medium for fluid-structure interaction. Therefore, the fluid and the solid surface interact through the laminar boundary layer. When the camber h and thickness b of the solid surface are within appropriate ranges, the arc surface has a rectifying and accelerating effect on the fluid. When the fluid is in a laminar state, there is a velocity gradient in its longitudinal direction. According to Bernoulli's theorem, the velocity gradient is equal to the pressure gradient, and this pressure gradient is the lift force. Similarly, when the fluid is in a laminar state, there is velocity kinetic energy, i.e., power, in its transverse direction. According to Newton's third law, that is, the action force and the reaction force are equal in magnitude and opposite in direction. The action force is the power, and the reaction force is the counter-power. Therefore, both the counter-power and the lift force are the basic functions of the laminar state. In fact, the main power of a rocket nozzle or a steam turbine moving blade is the counter-power of the fluid.

[0012] The inventor believes that the counter-power of the fluid is related to the flow state of the fluid. When the fluid is in a laminar state, the resistance is the smallest. Once the turbulent state appears, the resistance will gradually increase, and the counter-power will gradually decrease or even become zero. Therefore, the fluid must maintain a laminar state to maintain a stable power output. Only by maintaining a stable power output can there be a stable counter-power. For example, the moving blade of a steam turbine forms a convergent nozzle. The steam flow is restricted by this convergent nozzle, and the laminar state is more stable, so the efficiency of the counter-power is greater. Assuming that turbulence appears at the nozzle, the counter-power efficiency of the nozzle will surely decrease. Similarly, the counter-power of a rocket nozzle also depends on a stable laminar state. Assuming that turbulence appears at the rocket nozzle, the counter-power efficiency at that place will surely decrease. Therefore, the necessary condition for forming a stable counter-power is to maintain a stable laminar state.

[0013] The Reynolds number is a dimensionless parameter characterizing the flow state of the fluid. The actual Reynolds number = , where ρ is the fluid density, U is the flow velocity, L is the chord length of the arc surface, μ is the dynamic viscosity coefficient, and for air, μ = 1.82X •S. And the rated Reynolds number for the arc surface to maintain a laminar state is in the range of — . Therefore, as long as the actual Reynolds number of the arc surface does not exceed the rated Reynolds number, the flow state will remain in a laminar state unchanged.

[0014] The inventor believes that the structure of the willow-leaf-shaped blade (1) and the laminar state of the fluid are extremely similar to the structure of the convergent nozzle formed by the moving blade of a steam turbine and the rocket nozzle and their laminar states. According to the similarity principle, a counter-power can be formed on the upper and lower surfaces of the willow-leaf-shaped blade (1). Therefore, the only power to push the above willow-leaf-shaped blade (1) to rotate against the wind is the counter-power of the wind.

[0015] According to Newton's third law, the action force and the reaction force are equal in magnitude and opposite in direction. That is to say, the reaction force of the fluid is equal in magnitude and opposite in direction to its driving force. In fact, even for a standard streamlined body, the drag coefficient is 0.04 (see "Fluid Mechanics as I Understand It" by Wang Hongwei, published by National Defense Industry Press, the 1st edition, December 2014, page 177). Therefore, the reaction force efficiency of a standard streamlined body is equal to 0.96. So, the maximum reaction force efficiency of the above-mentioned willow-leaf-shaped blade (1) does not exceed 0.96, and the limit efficiency value is equal to 1.

[0016] The inventor believes that on the working surface of the airfoil blade of the existing vertical-axis H-type wind turbine, both lift and reaction force can be formed, and the efficiency of the reaction force is relatively high. However, the traditional airfoil theory holds that only lift can be formed on the surface of an airfoil or an airfoil blade, and no reaction force will be formed.

[0017] The specification appendix Figure 4 shows the working principle diagram of the existing vertical-axis Darrieus H-type wind turbine. As shown in this figure, only the natural angle of attack of the airfoil blade (5) in the right position is equal to 15°. Once it leaves this position, the natural angle of attack is no longer equal to 15°, and the lift coefficient will rapidly decrease until it becomes zero. This is one of the main reasons for the low efficiency of the vertical-axis wind turbine. As shown in this figure, the airfoil blades (2), (7), (5), and (8) of the existing vertical-axis wind turbine are all lift-type blades. Generally, the cross-sectional structure of a lift-type blade is airfoil-shaped, that is, the A surface and the B surface are asymmetric, and the working state parameters such as the zero-lift angle and the natural angle of attack α are both greater than zero. As a result, the rotational resistance angle Φ is also greater than 0°, which leads to a relatively large drag coefficient. This is the second main reason for the low efficiency of the existing vertical-axis wind turbine. When the natural wind acts on the airfoil blade (5), a relative wind force is formed on the leeward surface (B), and the relative wind force will necessarily form a fluid dynamic force , and the fluid dynamic force will form a lift , and the lift will form a driving force . At the same time, on the windward surface (A), the relative wind force will also form a fluid dynamic force , and the fluid dynamic force will form a reaction force and superimpose with the lift-driving force to jointly push the blade to rotate in the ω direction. At the same time, when the natural wind acts on the leeward surface (B) of the airfoil blade (2), a driving force is formed, which further pushes the blade to rotate in the ω direction.

[0018] Driven by the airfoil blades (5) and (2), the airfoil blades (7) and (8) will also rotate, and thus relative wind forces are formed on the windward surface (A) and the leeward surface (B) of the airfoil blades (7) and (8). , and the relative wind forces will necessarily form hydrodynamic forces , and the hydrodynamic forces on the (B) surface can simultaneously form lift and reaction forces , and the hydrodynamic forces on the (A) surface can also form reaction forces , and the lift will in turn form driving forces and be superimposed with the reaction forces to jointly drive the blade to rotate in the ω direction. As described above, the lift must first be converted into a driving force before it can become the power to drive the blade to rotate, and this conversion rate is not 100%, while the hydrodynamic forces can be 100% converted into the reaction forces that drive the blade to rotate. This is the advantage of the reaction forces.

[0019] The specification appendix Figure 5 gives a schematic diagram of the wind tunnel test of the vertical-axis willow-leaf-shaped reaction-force wind turbine (4). As shown in this figure, the outlet diameter Φ of the fan (1) is 1000 mm, the diameter Φ of this wind turbine (4) is 1630 mm, the distance between this wind turbine (4) and the fan (1) is 2715 mm, the measured maximum wind speed at a radius of 500 mm is 9 m / s. When the fan (1) is started, the measured wind turbine rotates slowly. When the rotational speed of the wind turbine (4) reaches the measured rotational speed, quickly tighten the handwheel of the brake (8). At this time, the maximum power value displayed on the display is the actual power value of the measured wind turbine. Wind tunnel test results on November 17, 2024: When the rotational speed n = 90 r / min, the measured power P s of the wind turbine (4) is 116 w.

[0022] The inventor of the present invention believes that the hub is an essential and important component of the wind turbine, and rotational work is the most basic function of the wind turbine. Once the wind turbine stops operating, it cannot perform work externally, and as long as the wind turbine rotates, it has a lever effect, that is, the blades of the wind turbine push the hub to rotate and perform work like a lever.

[0023] As we know, the theoretical power P z of the wind turbine = M n ·ω, where M nis torque, and ω is angular velocity. That is to say, when the angular velocity ω of the wind turbine is constant, the theoretical power P of the wind turbine z is proportional to the torque M n , and the torque M n is equal to the torsion force F n multiplied by the blade length R n . That is to say, the longer the blade, the greater the torque and the greater the theoretical power. This is the unique lever effect of the wind turbine. As we know, the torsion force where ρ is the air density, A n is the working area of the blade, U x is the relative velocity, i.e., the linear velocity, and U x = 2πR n ·n, and the angular velocity ω = U x / R n . Thus, we have: The working efficiency C of the wind turbine p = P s / P z , where P s is the measured power.

[0030] As shown in the attached instruction manual Figure 4 , the lift force formed by the hydrodynamic force on the surfaces of the airfoil blades (5), (7) and (8) = ρ . In the formula, is the windward area of the blade, and in the formula, is the relative wind speed, i.e., the linear velocity; at the same time, the reactive force formed by the hydrodynamic force = ρ . In the formula, is the windward area of the blade, and in the formula, is the natural wind speed, and the relative wind speed, i.e., the linear velocity = 2π •n. In the formula, is the radius of the support rod (3), and n is the rotational speed. That is to say, if the support rod (3) is long enough, the relative wind speed, i.e., the linear velocity will be large enough, and the lift force And the reaction force is large enough, which is the leverage of the blade. The main driving forces of the existing airfoil blades are the lift force and the reaction force, and the lift force and the reaction force are relative to the wind energy, while the relative wind energy is secondary wind energy and has no direct relationship with the natural wind energy. The natural wind energy is primary wind energy, and the primary wind energy can only play a role in starting the blade to rotate. Therefore, the lift force or the reaction force is proportional to the square of the relative wind speed, that is, the linear speed, and is proportional to the windward area of the airfoil blade, has no direct relationship with the natural wind energy, and has no relationship with the swept area. Therefore, the theoretical power of the wind turbine = ρ , where ρ in the formula is the air density, is the windward area of the blade, is the relative wind speed, that is, the linear speed. The working efficiency of the wind turbine = <1, where is the actual power of the wind turbine, is the theoretical power of the wind turbine, and the limit efficiency of the wind turbine = 1. Therefore, the brand-new theoretical power and efficiency formulas of the wind turbine are:

[0031] =( + + ••• • •+ ) ( is the total theoretical power of the wind turbine)------------(1)

[0032] = ρ (ρ is the air density, ρ = 1.2 kg / )----------(2)

[0033] ={ , ,• • • } ( is the surface area of all blades in n segments)---(3)

[0034] ={ , , ,• • • } ( is the linear speed at point n)--------- (4)

[0035] = 2π n ([[]] ​is the radius of the blade at point n, and n is the rotational speed) ------------ (5)

[0036] ={ ( + ), ( + ), • • • ( + ) --------- (6)

[0037] = / <1 ( is the efficiency of the wind turbine, is the actual power of the wind turbine) ------ (7)

[0038] The specification appendix Figure 6 gives the top view in the A direction of the above Figure 5 As shown in the figure, the willow leaf-shaped reaction blades (12) and (13) are arranged in a row and simultaneously utilize the natural wind force and the relative wind force and output power synchronously; (14) and (15) are arranged in a row and simultaneously utilize the relative wind force and output power synchronously; (16) and (17) are arranged in a row and simultaneously utilize the natural wind force and output power synchronously; (18) and (19) are arranged in a row and simultaneously utilize the relative wind force and output power synchronously. As shown in the figure, only the willow leaf-shaped reaction blades (12) and (13) and (16) and (17) can synchronously utilize the natural wind energy (F), while at the same time (14) and (15) and (18) and (19) cannot synchronously utilize the natural wind force .

[0039] The specification appendix Figure 7 gives the actual dimensions of the blades of the willow leaf-shaped reaction wind turbine (4) in the above Figure 5 As shown in the figure, the surface of the blade is divided into 8 approximate trapezoids, plus a tip end face (approximate triangle). Calculate the surface areas of these 8 approximate trapezoids respectively, multiply by 2 faces, then multiply by the number of blades 8, and then add the area of an approximate triangle multiplied by the number of blades 8, which is the total surface area of the 8 blades in each section. Through calculation, it is obtained that =0.096m²; =0.237m²; =0.296m²; =0.28m² =0.256m²; = 0.232 m²; = 0.212 m²; = 0.015 m²; = 0.024 m². The radius of the surface area of each section takes the median value, which are respectively: = 185 mm; = 255 mm; = 350 mm; = 450 mm; = 550 mm; = 650 mm; = 750 mm; = 807 mm; = 815 mm. The total windward area of the 8 blades of the wind turbine 8 = 0.824 m², and the swept area of the wind turbine = 3.14X = 2 m², so the solidity of the wind turbine, that is, the wind capture rate, is equal to 0.4, which is 4 times larger than the solidity of the three-blade wind turbine with the same diameter, that is, the wind capture rate.

[0040] As described above, the linear velocity = 2π •n. Substitute the above radius and the rotational speed n value into this formula to calculate the linear velocity values of each section, which are respectively: = 1.74 m / s, = 2.4 m / s, = 3.29 m / s, = 4.2 m / s, = 5.1 m / s, = 6.1 m / s, = 7 m / s, = 7.6 m / s. The theoretical power values of each section are respectively: = 0.3 kgm / s, = 1.96 kgm / s, = 5.8 kgm / s, = 12.4 kgm / s, = 20.3 kgm / s, = 31.5 kgm / s, = 43.6 kgm / s, = 3.95 kgm / s, = 6.3 kgm / s. Then, when the rotational speed of the wind turbine n = 90 r / min, the theoretical total power of the 8 blades is equal to the sum of the above theoretical power values, that is 126 kgm / s, while the measured power is 116 w. Then, the calculated efficiency = 116 w / 126 kgm / s = 0.92, and this efficiency far exceeds that of existing vertical-axis wind turbines. As we know, a high-efficiency wind turbine means it has the ability to utilize low-density natural wind energy, and it also means the wind turbine has a shorter blade length, a lower risk of blade breakage, and a lower cost.

[0041] The inventor believes that the vertical-axis willow-leaf-shaped double-rotor wind (reaction force) turbine structure and the method for efficient operation first proposed by the present invention are also applicable to tidal energy power generation devices and the method for efficient operation.

[0042] The specification appendix Figure 8 shows an assembly drawing of a vertical-axis double-turbine hydraulic (reaction force) power generation device. As shown in this figure, the primary turbine (1) has a shorter radius and is divided into two layers. The blades of each layer are connected to the square hub (2) along the horizontal direction; the secondary turbine (3) has a longer radius and only one layer. Each blade is connected to the vertical axis (4) along the horizontal direction. In this way, the blade itself is the power arm of the turbine, and the extension of this power arm is not restricted in space, and it is easy to enlarge the diameter of the turbine.

[0043] The primary turbine (1) utilizes natural hydraulic power to start the secondary turbine (3), and the main function of the secondary turbine (3) is to utilize the secondary water energy to output greater power, thereby driving the generator (7) to generate electricity.

[0044] The specification appendix Figure 9 shows the upward view from direction A of the above Figure 8 . As shown in this figure, the willow-leaf-shaped reaction force blades (11) and (12) of the primary turbine (1) are arranged in a row; (13) and (14) are arranged in a row; (15) and (16) are arranged in a row; (17) and (18) are arranged in a row. Since the natural angle of attack of the above-mentioned blades (11) and (12) as well as (15) and (16) is equal to 0°, these blades can efficiently utilize natural hydraulic power , and once these blades leave this position, the natural angle of attack will be greater than 0° (the so-called natural angle of attack is the angle between the natural flow direction and the chord line), and the utilization rate of the natural hydraulic power of the blades will decrease until it becomes zero.

[0045] As shown in this figure, the natural angle of attack of the willow-leaf-shaped reaction force blades (13) and (14) as well as (17) and (18) is equal to 90°, so these blades cannot utilize natural hydraulic power at this position . However, these blades can utilize relative hydraulic power , because the relative hydraulic power The flow direction is also relative. Therefore, the relative angle of attack of all the blades described above is equal to 0° (the so-called relative angle of attack is the angle between the relative flow direction and the chord line). When the relative angle of attack is equal to 0°, the rotational resistance angle Φ is also equal to 0°. When the rotational resistance angle Φ is equal to 0°, the rotational resistance is extremely small. Therefore, all these blades can efficiently utilize the relative water power .

[0046] The primary turbine (1) utilizes natural water power to drive the secondary turbine (3) to rotate, and the secondary turbine (3) utilizes relative water power , and the flow direction of the relative water power is also relative. Thus, the relative angle of attack of all the blades of the secondary turbine (3) is equal to 0°. Thus, this blade can efficiently utilize the relative water power at any position .

[0047] As shown in this figure, the shapes of all the tip wings (20) of the primary turbine (1) are eagle-beak type, and the shapes of all the tip wings (21) of the blades of the secondary turbine (3) are eagle-beak type. The eagle-beak type tip wings (20) and (21) can significantly reduce eddy current losses and noise.

[0048] The specification appendix Figure 10 gives the cross-sectional view in the B-B direction in the above Figure 9 . As shown in this figure, the willow-leaf type reaction blades (11) and (12) of the primary turbine (1) are arranged side by side and both have their blade heads facing forward. The cross-sectional structure of these two blades is willow-leaf type, that is, the upper and lower arc surfaces are completely symmetrical, and the camber h and the thickness b are both within appropriate ranges. The method for these two blades to work efficiently is: to maintain a completely horizontal working state, that is, both the relative angle of attack and the zero-lift angle are equal to 0°. As a result, the rotational resistance angle Φ of these two blades is also equal to 0°. This leads to an extremely small resistance coefficient, and the eddy current loss at the blade tail is close to zero. Therefore, the reaction efficiency is very high. These two blades are arranged in a row and connected end to end. The leading edge of the rear blade is exactly aligned with the blade tail of the front blade. In this way, when the water flow passes over these two blades, a wavy laminar flow state is formed, and further, these two blades can both maintain a relatively stable laminar flow state at the same time, and further, the hydrodynamic forces of both of these two blades can efficiently form reaction forces , so that both of these two blades can output power synchronously in a relatively stable manner.

[0049] The specification appendix Figure 11 gives the cross-sectional view in the C-C direction in the above Figure 9 . As shown in this figure, the willow-leaf type reaction blades (15) and (16) of the primary turbine (1) are arranged side by side and both have their blade tails facing forward. We know that when the blade tail faces forward, the driving force It increases significantly. The cross-sectional structure of these two blades is willow-leaf shaped, that is, the upper and lower arc surfaces are completely symmetrical, and the camber h and thickness b are within appropriate ranges. The working state of these two blades is set in a completely horizontal row arrangement with the leaf tails facing forward. When the water flow sweeps over the surfaces of these two blades, a stable laminar flow state can be maintained, and when the water flow sweeps over the leading edges of these two blades, turbulence can be formed. In this way, the driving forces of these two blades will increase synchronously, which cannot be achieved by airfoil blades.

[0050] The attached drawings of the specification Figure 12 give the above Figure 9 A-A sectional view, as shown in this figure, all the blades of the secondary turbine (3) utilize relative water power , and the flow direction of the relative water power is also relative. Therefore, the relative angle of attack of all the blades at any position is equal to 0°. Therefore, all the blades can output power synchronously and efficiently, just like the blades of a horizontal-axis wind turbine. In this way, the problem that the blades of the existing vertical-axis turbine cannot output power synchronously is solved. The cross-sectional structure of all the blades of the secondary turbine (3) is willow-leaf shaped, that is, the upper and lower arc surfaces are completely symmetrical. The method for these blades to work efficiently is to maintain a completely horizontal working state, that is, the zero-lift angle and the relative angle of attack are both equal to 0°. As a result, the rotational resistance angle is also equal to 0°, which leads to very small rotational resistance and leaf-tail eddy current losses, a relatively stable laminar flow state, and a relatively high efficiency of the reaction force. In addition, since the force-bearing direction of the willow-leaf shaped horizontal blade is parallel to the chord length direction, and the blade has a relatively high strength in the chord length direction, the risk of blade breakage is relatively low.

[0051] Main features:

[0052] (1). The secondary turbine is started by the primary turbine using natural water power, and the relative angle of attack of all the blades of the secondary turbine at any position is equal to 0°. Therefore, all the blades can output power synchronously, and this can only be achieved by willow-leaf shaped reaction blades.

[0053] (2). The hub of the primary turbine is square, and every two blades are arranged in a row without affecting each other's synchronous power output, and this can only be achieved by willow-leaf shaped reaction blades.

[0054] (3). Whether it is the primary turbine or the secondary turbine, all their blades are connected to the hub in the horizontal direction. In this way, the length of the blades is not restricted. Just like the blades of a horizontal-axis wind turbine, the diameter of the turbine can be appropriately enlarged, and this solves the problem that the existing vertical-axis turbine cannot be enlarged, and this can only be achieved by willow-leaf shaped reaction blades.

[0055] (4). All the blades of the primary turbine and the secondary turbine adopt willow-leaf shaped reaction blades, and the laminar flow state of this blade is relatively stable, and the theoretical efficiency of the reaction force is as high as 0.96.

[0056] (5). The diameter of the vertical-axis turbine is not limited by the water depth.

[0057] (6). Neither the primary turbine nor the secondary turbine requires a yaw mechanism and can accept water flow from any direction at any time, which is crucial for harnessing tidal energy.

[0058] (7). The tip vortex loss or trailing vortex loss of the willow-leaf-shaped reaction blade is very small.

[0059] (8). The generator is not underwater, there is no risk of leakage, and it is easy to maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 ----- shows a schematic diagram of a vertical-axis willow-leaf-shaped blade rotating against the wind.

[0061] Figure 2 ----- shows the above Figure 1 sectional view taken along the line A-A in the above.

[0062] Figure 3 ----- shows the cross-sectional structure and lift working principle diagram of a general airfoil lift blade.

[0063] Figure 4 ----- shows the working principle diagram of an existing vertical-axis H-type wind turbine.

[0064] Figure 5 ----- shows a schematic diagram of a wind tunnel test of a vertical-axis willow-leaf-shaped reaction wind turbine (4).

[0065] Figure 6 ----- shows the above Figure 5 top view taken along the line A in the above.

[0066] Figure 7 ----- shows the above Figure 5 actual size of the blade of the reaction wind turbine (4) in the above.

[0067] Figure 8 ---- shows the general assembly drawing of a vertical-axis willow-leaf-shaped double-turbine hydraulic (reaction) power generation device.

[0068] Figure 9 ---- shows the above Figure 8 top view taken along the line A in the above.

[0069] Figure 10 ---- shows the above Figure 9 sectional view taken along the line B-B in the above.

[0070] Figure 11 ---- shows the above Figure 9Middle CC section view.

[0071] Figure 12 ------Given the above Figure 9 AA section view.

[0072] Specific implementation method: Figure 8 As shown in ˎ9ˎ10ˎ11 and 12, all blades of the primary turbine (1) are connected to the square hub (2) in the horizontal direction, and the square hub (2) is fixed on the vertical shaft (4). All blades of the secondary turbine (3) are connected to the vertical shaft (4) in the horizontal direction. The vertical shaft (4) is connected to the generator (7) through the bearing (5) and the coupling (6). The generator (7) is fixed on the platform (8), and the platform (8) is fixed to the anchor (10) through the cable (9). The willow-leaf reaction blades (11) and (12) of the primary turbine (1) are arranged in a row, (13) and (14) are arranged in a row, (15) and (16) are arranged in a row, and (17) and (18) are arranged in a row and are respectively connected to the square hub (2). The cross-sectional structure of all blades of the primary turbine (1) and all blades of the secondary turbine (3) is a willow-leaf type, i.e., the upper and lower arc surfaces are completely symmetrical, and the curvature h and thickness b are within a suitable range. The method for the blade to work efficiently is to maintain a completely horizontal working state, i.e., the zero lift angle and the angle of attack are both equal to 0°. The blade tips (20) and (21) of all blades of the primary turbine (1) and the secondary turbine (3) are both hawk-beak type.

[0073] When the primary turbine (1) uses natural water power to start the secondary turbine (3) to rotate, all blades of the secondary turbine (3) use relative water power. Since the direction of the relative water power is also relative, the relative angle of attack of the blades is equal to 0° at any position, so the rotation resistance is extremely small and the reaction force efficiency is very high. The rotation of the primary turbine (1) and the secondary turbine (3) drives the vertical shaft (4) to rotate, and the vertical shaft (4) drives the generator (7) to rotate through the coupling (6), and the generator (7) converts mechanical energy into electrical energy.

[0074] We know that the energy density of water energy is 50-70 times that of air, and the lifespan of tidal energy is equivalent to the lifespan of the earth, which is longer than the lifespan of nuclear energy, because the lifespan of nuclear energy is only more than 5,700 years. Therefore, tidal energy is a super stable energy source.

[0075] We know that the dynamic viscosity coefficient of water at zero degrees Celsius is μ=1.78X •S, and the dynamic viscosity coefficient of air at 20 degrees Celsius is μ=1.82X •S, it can be seen that the dynamic viscosity coefficient of water is much greater than that of air, so the laminar flow state on the blade surface of a tidal energy turbine is much more stable than the laminar flow state on the blade surface of a wind turbine.

[0076] As we know, the wind wheel has a lever effect. Therefore, the larger the diameter of the wind wheel, the larger the tip speed ratio, and the greater the output power of the wind wheel. Similarly, the larger the diameter of the tidal energy turbine, the larger the tip speed ratio, and the greater the output power of the turbine, and this can only be achieved by the reaction turbine proposed by the present invention.

[0077] The vertical-axis tidal energy (reaction) power generation device and the efficient working method first proposed by the present invention are exactly the same as those of the vertical-axis double-wind-wheel wind power (reaction) power generation device and the working method. Therefore, the offshore wind power platform coupled with the tidal energy power generation device is the best solution for the comprehensive utilization of ocean energy.

Claims

1. A vertical axis twin-turbine tidal energy (reverse power) power generation device and a method for high efficiency operation, comprising a primary turbine (1), a square hub (2), a secondary turbine (3), a vertical axis (4), a bearing (5), a coupling (6), a generator (7), a platform (8), a cable (9) and an anchor (10), characterized in that The primary turbine (1) is connected to the square hub (2), the square hub (2) is connected to the vertical shaft (4), the secondary turbine (3) is connected to the vertical shaft (4), the vertical shaft (4) is connected to the generator (7) through a bearing (5) and a coupling (6), the generator (7) is fixed on a platform (8), and the platform (8) is connected to an anchor (10) through a cable (9).

2. The primary turbine (1) according to claim 1, characterized in that The willow-leaf-shaped reaction blades (11) and (12) are arranged in a row, (13) and (14) are arranged in a row, (15) and (16) are arranged in a row, and (17) and (18) are arranged in a row and are respectively connected to the square hub (2) in the horizontal direction.

3. All blades of the primary turbine (1) and the secondary turbine (3) according to claims 1 and 2, characterized in that The method for its efficient operation is to maintain a completely horizontal working state, that is, the zero lift angle and the relative angle of attack are both equal to 0°.

4. All blades of the primary turbine (1) and the secondary turbine (3) according to claims 1 and 2, characterized in that The blade tip wings (20) and (21) are shaped like hawk beaks.

Images