TWM588736U - Auxiliary device for horizontal axis wind turbine blade - Google Patents

Abstract

Auxiliary device for horizontal axis wind turbine blades, including a base, having a fixed surface and an exposed surface opposite to each other, the fixed surface is fixed on the suction side surface of the blade and is located at the position where the thickness of the blade is the largest; and two auxiliary blocks, both of which It is non-parallel fixed to the exposed surface of the base, and the auxiliary block has a first auxiliary surface and a second auxiliary surface, and the first auxiliary surface and the second auxiliary surface are respectively connected to the exposed surface with one end; Turbulence is generated on the suction side of the blade and lifts the blade.

Description

Auxiliary device for horizontal axis wind turbine blade

This creation is about an auxiliary device installed on the blade, especially applied to the position of the suction side of the blade of the horizontal axis wind turbine.

In recent years, the price of biochemical energy has risen, and countries are actively developing sustainable or renewable energy technologies. The currently accepted alternatives are solar power, wind power, and tidal power generation. It is expected that they can gradually replace nuclear power plants and coal-fired power plants that countries currently rely on in the future. Thermal power plant. Especially after the severe nuclear power plant disasters caused by the earthquake in Japan, countries have established mechanisms for the withdrawal or abolition of nuclear and thermal power plants. In order to make up for the shortage of power in the aforementioned power plants, it is necessary to accelerate the development and use of the aforementioned sustainable energy.

At present, most of the wind generators erected in the coastal areas of the countries or even offshore are horizontal-axis generators. Such generators need to build ground piles on the ground, and then install the tower base on the ground piles. The upper end of the tower base It is an organic cabin, a generator set, and rotor blades are installed. The propeller is facing the wind direction, and the blades are driven by the wind to rotate the internal rotor mechanism to drive the generator.

The shape of the blade cross section of a wind turbine is called a blade shape, and the collection characteristics of the blade cross section are closely related to the aerodynamics of the blade. The cross-section of the blade is not symmetrical. It mainly has a curved suction surface and a flat pressure surface. When the airflow pushes the blade and passes through the blade, the airflow is divided into two parts, and part of the airflow flows from the suction surface of the blade. However, another part of the airflow flows from the pressure surface of the blade. Since the suction surface is more curved and the pressure surface is flatter, the flow velocity of the airflow through the suction surface is a block from the suction surface. According to the principles of fluid mechanics, if the airflow velocity is slow, the atmospheric pressure is greater, and if the airflow velocity is faster, the atmospheric pressure is smaller. In this way, it can be inferred that the pressure on the pressure surface of the blade is higher than the pressure on the suction surface of the blade, and the pressure difference between the two forms the lift of the blade. . In other words, the faster the airflow speed, the greater the lift generated by the blades. When the lift is greater than the resistance, the wind turbine can be propelled to generate electricity, and when the lift is less than the resistance, it cannot be driven to generate electricity.

In addition, the blade can generate lift because the blade has a pressure difference between the suction surface and the pressure surface, provided that the airflow on the blade surface is not separated. However, when the blade rotates in the atmosphere at a certain angle of inclination (called the angle of attack), there will be inconsistent pressure on the upper and lower surfaces, which will also produce lift.

When the angle of attack between the blade and the airflow direction increases, the lift will increase and the resistance will increase. If the angle of attack of the blade is large to a certain degree, the blade is equivalent to a flat plate erected in the airflow. Because the angle is too large, the speed is too fast , The airflow flowing through the suction surface cannot be coherent and will be separated. At the same time, driven by the outer airflow, the flow to the trailing edge will be rolled into a closed vortex, also known as the separation vortex. This refers to the pressure in the rotating separation vortex is not The pressure is equal to the airflow pressure on the suction surface, so the pressure difference between the suction surface and the pressure surface of the blade will be much smaller, causing the lift of the blade to be smaller than the original state, so that the efficiency of the entire power generation system is greatly reduced .

Generally speaking, it is better to set the angle of the blade to 8 to 15 degrees when designing the angle of attack of the blade. After 15 degrees, the airflow on the suction surface of the blade will separate, generating vortices, the lift will drop rapidly, and the resistance will rise sharply. The phenomenon is called stall; the effect of blade stall on the entire propeller is as follows:

First, the pressure difference loss on both sides of the blade increases the running resistance of the blade, reduces the operating lift, increases the starting wind speed and rated wind speed of the blade, and reduces the overall operating efficiency of the blade.

Second, the unstable vortex will cause the blade to tremble during operation, shortening the service life of the blade and internal rotor mechanism.

The main purpose of the creation of the auxiliary device for horizontal axis wind turbine blades is to solve the problems of early stall of the blades caused by airflow separation, reducing the problems of blade aerodynamic performance and power conversion.

An auxiliary device for a blade of a horizontal axis wind power generator, comprising: a base having a fixed surface and an exposed surface opposite to each other, the fixed surface is fixed on the suction side surface of the blade and is located at the position where the blade thickness is maximum; and two auxiliary The two blocks are non-parallel fixed to the exposed surface of the base, and the two auxiliary blocks have a first auxiliary surface and a second auxiliary surface, and the first auxiliary surface and the second auxiliary surface respectively have one end Connected to the exposed surface; the auxiliary device generates turbulent flow on the suction side of the blade to lift the blade lift.

In order to solve the problem of the aerodynamic performance of the blade caused by the separation of the aforementioned airflow, the authoring aid is installed on the suction side (suction surface) of the blade, especially where it is installed on one or several narrow and long wings on the leading edge of the blade. Such a novel mechanism that can increase the critical work angle of the blade to live the increase of lift force, the main function is to effectively prevent the premature separation of the airflow.

The working principle of this creation aid is that the auxiliary block can be close to the vertical shape with respect to the surface of the blade and its aspect ratio is smaller than that of the wing. Therefore, it can generate wingtip vortices in the airflow like the conventional airfoil. Due to its small aspect ratio, Therefore, the strength of the wingtip vortex is relatively strong, which can transfer Nengliang to the airflow separation layer, so that after the stagnation state of the airflow separation layer flow field obtains additional energy, it can continue to adhere to the blade surface without separation. This is the basic working principle of this authoring assistant.

The setting of the angle and interval of this creation aid has been proved by past aerodynamic experiments that when the angle of attack α≧7, the spreading cabinet λ=12㎜ and the installation declination angle=20, the drag reduction effect is better. The effect of the installation angle of the auxiliary device on the separation control of the gas separation layer is mainly reflected in the strength of the vortex. If the installation deflection angle is too small, the intensity of the generated vortex is not strong, and it has little effect on the turbulent mixing in the air separation layer. Therefore, the optimal installation declination angle is defined as β=20˚. The co-rotating and slanting turbulence interacts with the boundary layer to produce co-rotating and counter-rotating vortices, respectively. The co-rotating and flowing vortices can produce strong local control, while the counter-rotating vorticity can The boundary layer is uniformly controlled and has a large flow direction control area, so the setting of the creative assistant is contrary to the relative arrangement, and the angle is set to an off angle of 20˚.

The material of this creation aid can be made of various materials, such as aluminum alloy, stainless steel, plastic, etc. Due to the harsh environment of wind turbines, the wear resistance and anti-aging properties of metal materials are better than those of plastics, and the forming technology of aluminum alloy is simpler than stainless steel, and the cost is lower.佳材料。 Good materials.

The fixation method of this creation aid is required to be firmly attached to the suction side (face) of the blade, and it has been operating in a harsh environment for up to 20 years. Therefore, a stable and reliable installation method is required. You can choose glue and riveting technology fixed.

Using this creation aid to install on the blade can improve the aerodynamic performance of the blade, as described below:

First, improve the aerodynamic signal energy of the blade. After the auxiliary blade is installed, the lift resistance ratio of the blade can be improved, so that the blade rotates at a lower starting wind speed and can reach the rated power at a lower rated wind speed. At high wind speeds, the output power is also more stable with the county. Under the same wind conditions, increase wind power by 3% to 5%.

Second, prolong the service life of the blade. The generation of eddy current is accompanied by irregular air movement, which causes a large amount of vibration in the non-design state when the blade is running. This creation aid can effectively prevent the blade from shaking during operation and can be extended. The service life of the blade.

Referring to the first to fourth figures, an auxiliary device 1 for a horizontal axis wind turbine blade is disclosed, which includes: a base 11 having a fixed surface 12 and an exposed surface 13 opposite to each other, the fixed surface 12 It is fixed on the surface of the suction side 21 of the blade 2 and is located at the maximum thickness of the blade 2; and two auxiliary blocks 14, both of which are fixed non-parallel to the exposed surface 13 of the base 11, and the two auxiliary blocks 14 have a first The auxiliary surface 141, a second auxiliary surface 142, and the first auxiliary surface 141 and the second auxiliary surface 142 are connected to the exposed surface 13 at one end respectively; the auxiliary device 1 generates turbulence on the suction side 21 of the blade 2 And lift the blade 2 liters. The aforementioned blade 2 refers to a propeller blade of a horizontal-axis wind turbine.

In this way, the creation aid 1 is installed on the surface of the suction side 21 of the blade, which can increase the blade's adjacent angle of attack to obtain the effect of lowering the resistance and increasing the lift, and can also prevent the blade 2 from turning down due to unstable vortex Tremor, prolong the service life of the blade 2 and the related transmission mechanism inside the generator.

As shown in the fifth figure, the auxiliary device 1 of the present invention is installed at the position where the thickness of the blade 2 is maximum, and is located on the surface of the suction side 21 of the blade 2. As shown in the first figure, the two auxiliary blocks 14 have an adjacent surface 143 connecting one of the first auxiliary surface 141 and the second auxiliary surface 142, and the two auxiliary blocks 14 have two opposite wind cutting surfaces 144 and are connected于此vious exposed surface 13. The two tangent wind surfaces 144 are connected to the first auxiliary surface 141, the second auxiliary surface 142 and the adjacent surface 143 respectively. Through the aforementioned three-dimensional structural characteristics of the auxiliary block 14, when the airflow passes through the auxiliary device 1, a vortex can be generated to achieve the purpose and effect of turbulence.

It is worth mentioning that the first auxiliary surface 141 of the creative auxiliary block 14 is oriented toward the leading edge 22 of the blade 2, and the second auxiliary surface 142 is oriented toward the trailing edge 23 of the blade 2, as shown in the fifth figure. The adjacent surface 143 is located at the maximum distance from the surface of the suction side 21 of the blade 2 in the auxiliary block 14. The declination angle X between the first auxiliary surface 141 and the exposed surface 13 is 20˚, as shown in the second figure.

Regarding the installation of the auxiliary device 1 on the suction side 21 of the blade 2, the theoretical installation position is determined by measuring the thickest point through the design drawing of the blade 2, and considering the convenience of installation, the installation point is established every 1 meter. Measure the distance from the theoretical installation position to the trailing edge of the blade 2.

1. Connect all the theoretical installation points in the area from 3 meters to 25 meters away from the root 24 of the blade 2 in a straight line, and mark the installation position line of the theoretical auxiliary device.

2. Since the suction side 21 of the blade 2 has a certain curvature, in order to better fit the base 11 of the auxiliary device on the suction side 21, the fixing surface 12 of the base 11 corresponds to the surface of the blade 2 in an arc shape, and the base 11 The length is set to 0.5 meters.

Regarding the creation aid 1 installed on the suction side 21 of the blade 2, there is a glue layer 3 between the fixing surface 12 of the base 11 and the surface of the suction side 21 of the blade 2, the base is formed by the opposite sides of the glue layer 3 11 glued to the blade 2, as shown in the sixth figure. Or further include a riveting set (not shown in the figure) fixing the base 11 to the surface of the blade 2.

A plurality of auxiliary devices 1 are connected and installed on the blade 2 and are between 3 meters and 25 meters from the root 24 of the blade 2. Or a whole long strip of metal sheet, after punching technology, several auxiliary blocks 14 are folded out, as shown in the seventh figure.

1‧‧‧Auxiliary 11‧‧‧Base 12‧‧‧Fixed surface 13‧‧‧ exposed surface 14‧‧‧ auxiliary block 141‧‧‧The first auxiliary surface 142‧‧‧Second auxiliary surface 143‧‧‧adjacent face 144‧‧‧cut wind face 2‧‧‧blade 21‧‧‧Suction side 22‧‧‧ leading edge 23‧‧‧back edge 24‧‧‧Root 3‧‧‧Glue layer

The first picture is a three-dimensional schematic diagram of the authoring assistant.

The second picture is a top view of the authoring assistant.

The third picture is a schematic diagram of the creation of several auxiliary devices combined with the blade.

The fourth picture is a schematic diagram of the authoring assistant combined with the blade.

The fifth picture is a schematic diagram of this creation.

The sixth diagram is an enlarged schematic diagram of the fifth diagram.

The seventh picture is a schematic diagram of the creation assistant in a strip shape.

1‧‧‧Auxiliary

11‧‧‧Base

12‧‧‧Fixed surface

13‧‧‧ exposed surface

14‧‧‧ auxiliary block

141‧‧‧The first auxiliary surface

142‧‧‧Second auxiliary surface

143‧‧‧adjacent face

144‧‧‧cut wind face

Claims (9)

Auxiliary device for horizontal axis wind turbine blades, including: A base with a fixed surface and an exposed surface opposite to each other, the fixed surface is fixed on the suction side surface of the blade and is located at the position where the blade has the largest thickness; And two auxiliary blocks, both of which are non-parallel fixed to the exposed surface of the base, and the two auxiliary blocks have a first auxiliary surface, a second auxiliary surface, and the first auxiliary surface and the second auxiliary surface One end is connected to the exposed surface at one end; the auxiliary device generates turbulent flow on the suction side of the blade to increase the lift of the blade. The auxiliary device of the horizontal-axis wind turbine blade according to claim 1, wherein the two auxiliary blocks have an adjacent surface connecting the first auxiliary surface and the second auxiliary surface, and the two auxiliary blocks have opposite two Cut the wind and connect to the exposed surface. The auxiliary device of the horizontal-axis wind turbine blade according to claim 2, wherein the two tangential wind surfaces are respectively connected to the first auxiliary surface, the second auxiliary surface, and the two sides of the adjacent surface. The auxiliary device of the horizontal axis wind turbine blade according to claim 1, wherein the fixed surface of the base corresponds to the blade surface in an arc shape. The auxiliary device of the horizontal-axis wind turbine blade according to any one of claim 1 to claim 4, wherein a glue layer is provided between the fixing surface of the base and the surface of the blade, and is formed by opposite sides of the glue layer Glue the base to the blade. The auxiliary device of the horizontal-axis wind turbine blade according to any one of claim 1 to claim 4, further comprising a riveting set to fix the base to the surface of the blade. The auxiliary device of the horizontal-axis wind turbine blade according to claim 1, wherein a plurality of auxiliary devices are connected and installed on the blade and are between 3 meters and 25 meters from the root of the blade. The auxiliary device of the horizontal axis wind turbine blade according to claim 1, wherein the auxiliary device is made of aluminum alloy, stainless steel or plastic material. The auxiliary device of the horizontal axis wind turbine blade as described in claim 1, wherein the auxiliary block has an off angle of 20˚ with respect to the exposed surface.

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