JP5569845B2 - Aerodynamically controlled wing device using dielectric barrier discharge - Google Patents

Description

  The present invention relates to a dielectric barrier discharge utilizing aerodynamic characteristic control wing apparatus that can arbitrarily generate surface plasma by dielectric barrier discharge on the surface of a wing to control aerodynamic characteristics of the wing.

  Various actuators have been developed so far, but in recent years, actuators using surface plasma have attracted attention. For example, as shown in FIG. 8A, when a front surface side electrode 52 and a back surface side electrode 53 are provided across an insulator 51 such as resin or ceramic, and an AC electric field is generated by an AC power source 54 on both electrodes, This utilizes the fact that a plasma jet 56 is generated from the edge 55 of the surface-side electrode 52 along the surface of the insulator 51 and is called a dielectric barrier discharge actuator or a surface plasma actuator. In particular, since this dielectric barrier discharge induces surrounding gas and generates an induced air flow 57, studies have been made to effectively use this action.

  As one of them, for example, the dielectric barrier discharge device 59 as described above is provided on the surface of the blade 58 as shown in FIG. 9A at a portion where the air flow is easily separated from the blade surface. Shows the surface side electrodes 52 formed in a row on the surface of the blade. When such a dielectric barrier discharge device 59 is used, a plasma jet is generated at the edge 55 of the surface-side electrode 52 according to the above principle as shown in FIG. 9B.

  As a result, the airflow flowing on the surface of the blade 58 generates turbulence or vortex due to the backflow at the rear of the blade as shown in FIG. At this time, when the dielectric barrier discharge device is turned on, it is influenced by the principle of generation of the induced air current, and the peeling that tends to occur in this portion can be eliminated as shown in FIG. In particular, the plasma generated by such dielectric barrier discharge only needs to form a thin film as a surface electrode on the blade surface, so that there is little influence of air resistance or the like on the airflow flowing on the blade surface, and there is no mechanical working part. Therefore, it is expected to be able to operate stably without failure.

  In particular, as shown in FIG. 8 (a), the AC power supply 54 can be controlled by the control device 60, the gas velocity and temperature are detected by the sensor 59, and the control device 60 controls the AC power supply 54 by the signal. Thus, it is possible to prevent the generation of vortex flow corresponding to the conditions at that time. As a control signal at this time, for example, as shown in FIG. 8 (b), an AC pulse having a predetermined narrow width is output for 1/15 seconds in the illustrated example, and further 13/30 seconds thereafter in the illustrated example. The same AC pulse is output after having stopped. When a stronger plasma jet is to be generated from such a control state, it can be dealt with by performing duty ratio control for increasing the pulse supply time as shown in FIG. 5C, for example.

  The plasma generated by such a dielectric barrier discharge device can generate various plasma jets depending on the shape and arrangement of various electrodes previously proposed by the present inventors, and the vortex flow of the blade as described above. In addition to performing an anti-separation effect by generation control, it can be considered to be used as various actuators. The plasma actuator is described in detail in the following document.

Roth, J. R., Sherman, D. M., and Wilkinson, S. P. (1998) .Boundary layer flow control with a one atmosphere uniform glow discharge.AIAA Paper 98-0328, 36th Aerospace Sciences Meeting and Exhibit, Reno, Nevada. Corke, TC, Jumper, EJ, Post, ML, Orlov, D., and McLaughlin, TE (2002) .Application of weakly-ionized plasmas as wing flow-control devices.AIAA paper 2002-0350, 40th Aerospace Sciences Meeting & Exhibit , Reno, Nevada.

  As described above, plasma generated by dielectric barrier discharge is expected as a technique for improving aerodynamic characteristics in various fluid machines, and as one of the fields, it is attracting attention to be used for a blade for wind power generation.

  Wind power generation technology has attracted worldwide attention as a technology for removing oil and environment, and many wind power generation devices have been installed, and research and development have been widely conducted. Conventionally, the basic idea in the development of wind power generation systems is to improve the characteristics of turbine blades for wind power generation in an ideal environment, and the environment in which the wind power generation system is installed (wind direction, average wind speed, topography) ) Is a suitable setting. In particular, in Japan, wind speed and wind direction fluctuations increase due to complicated and undulating terrain and seasonal wind changes, so a wind power generation system with a wider range and excellent characteristics is required.

  In a wind power generation system, there are mainly two factors that cause the operating rate and facility utilization rate to decrease hydrodynamically. First, even when wind is blowing from the front, if the flow velocity does not reach the cut-in wind speed, the blade cannot rotate, resulting in a non-operating state in which power generation itself cannot be performed. Since the blade characteristics and the generator starting torque vary from model to model, the cut-in wind speed varies, but it is approximately 2.5 m / s to 3 m / s.

  Even when the average flow velocity reaches the cut-in wind speed, the wind direction must be within the setting range of the angle of attack for obtaining the lift necessary for the rotation of the blade. Therefore, in an environment where the wind direction and the wind speed fluctuate with time, unless the wind for starting the rotation is accurately captured, the chance to overcome the static friction and rotate is lost.

  Second, even when the rotation is overcome by overcoming the static friction, the dynamic characteristics are deteriorated due to the stall caused by the change of the wind condition. Under low speed conditions (low Reynolds number), laminar flow separation occurs at a low angle of attack, and the flow largely separates from the vicinity of the leading edge of the airfoil and stalls in many cases. Even when the flow is separated from the laminar flow, the operation rate can be maintained because the blades are rotating, but since sufficient lift is not obtained, the amount of power generation relative to the wind speed falls, resulting in the facility utilization rate. Leading to a decline. On the other hand, under conditions where the flow velocity is high (high Reynolds number), high power generation can be expected, but stalling may occur due to flow separation from the trailing edge of the blade, called turbulent separation.

  When turbulent separation occurs, an oscillating flow is induced downstream of the blade, and wind speed fluctuations overlap in the field. In the worst case, the blade may be damaged due to overload or vibration. Such a situation is a problem that should be assumed in Japan's wind environment, such as typhoons and gusts that occur at the turn of the season, and it is often necessary to forcibly stop the blade from the viewpoint of safety, resulting in facility use. This leads to a decline in the rate. Thus, no matter how high the performance of the fixed wing is in the laboratory, there are often cases where the power generation amount as expected in the natural environment cannot be obtained.

  As described above, wind power generation systems require blades that rotate stably and efficiently in response to winds whose wind direction changes from moment to moment. Therefore, there is a need for the development of a wind power generation system equipped with blades that can cope with such environmental changes.

  The technology for controlling the airflow on the surface of the wing is required not only in the wind power generation system as described above but also in a wide range of fields such as aircraft wing, jet engine blade, turbocharger blade, and the like. However, in particular in the field of using various rotary blades, it is extremely difficult to apply to actual rotating blades.

  Therefore, in the present invention, when the flow of the blade surface is controlled by the plasma generation by the dielectric barrier discharge as described above, the flow state of the blade surface is reliably detected without being influenced by the surrounding environment, and the dielectric barrier discharge is performed. It is possible to control the aerodynamic characteristics by using, and especially applicable to rotor blades such as wind power generators, it is possible to operate the wind power generation system stably and with high efficiency. The main object is to provide an aerodynamic control wing device using dielectric barrier discharge that can be applied to a device equipped with wings.

  In order to solve the above problems, a dielectric barrier discharge utilizing aerodynamic control wing device according to the present invention has a cantilever projection that protrudes to receive a fluid around the wing, and a fiber grating fixed to the cantilever projection. An optical fiber having a section, a data analysis section for detecting distortion of the cantilever projection by analyzing light data from a fiber grating section of the optical fiber, and a dielectric barrier discharge section fixed to the wing. A high-frequency voltage control unit that controls a high-frequency voltage supplied to the dielectric barrier discharge unit, wherein the high-frequency voltage control unit uses the data analysis result of the data analysis unit to supply the high-frequency voltage supplied to the dielectric barrier discharge unit. The voltage is controlled.

  Another dielectric barrier discharge utilizing aerodynamic control wing apparatus according to the present invention is the above dielectric barrier discharge utilizing aerodynamic control wing apparatus, wherein the dielectric barrier discharge utilizing aerodynamic control wing apparatus is adjacent to a fiber grating portion fixed to the cantilever protrusion, and It is characterized in that another fiber grating portion for data reference is fixed at a position not affected by distortion.

  Another dielectric barrier discharge utilizing aerodynamic control wing apparatus according to the present invention is the above dielectric barrier discharge utilizing aerodynamic control wing apparatus, wherein the wing is a rotating wing and rotates together with the wing by being fixed to the cantilever projection. The rotation-side optical fiber connected to the fiber grating section is connected to the fixed-side optical fiber so that data can be transmitted and received by an optical fiber rotation joint.

In another dielectric barrier discharge utilizing aerodynamic control blade device according to the present invention, the power supplied to the dielectric barrier discharge unit is fixed to the axis of the rotor blade from the primary coil provided on the fixed side and close to the primary coil. Then, a battery provided on the rotating side is charged from the fixed side by supplying current to the rotating secondary coil.

  In another dielectric barrier discharge utilizing aerodynamic control wing apparatus according to the present invention, in the dielectric barrier discharge utilizing aerodynamic control wing apparatus, fiber grating portions fixed to the cantilever projections are all connected in series by one optical fiber. It is connected.

  Another dielectric barrier discharge utilizing aerodynamic control wing apparatus according to the present invention is characterized in that the cantilever projection is integrally formed with the wing in the dielectric barrier discharge utilizing aerodynamic control wing apparatus.

  Another dielectric barrier discharge utilizing aerodynamic control wing apparatus according to the present invention is the above dielectric barrier discharge utilizing aerodynamic control wing apparatus, wherein the cantilever projection is formed integrally with a member constituting a part of the wing. And a predetermined wing is formed by fixing a part of the wing to the wing body.

  In another dielectric barrier discharge utilizing aerodynamic control wing apparatus according to the present invention, in the dielectric barrier discharge utilizing aerodynamic control wing apparatus, each of the cantilever protrusions is composed of members having different cantilever protrusion shapes. In addition, the members can be used in any combination.

  Since the present invention is configured as described above, when the flow of the blade surface is controlled by the generation of plasma due to the dielectric barrier discharge, the flow state of the blade surface is reliably detected without being affected by the surrounding environment. It is possible to control aerodynamic characteristics by barrier discharge, and it can be applied to rotor blades such as wind power generators in particular, and wind power generation system can be operated stably and highly efficiently. It is possible to provide an aerodynamic control blade device using a dielectric barrier discharge that can be applied to a device having a plurality of rotor blades.

It is a figure which shows the example which utilized this invention for the wind power generation system. It is a figure which shows the example which applies FBG to a cantilever and detects an air flow. It is a figure which shows the principle of a fiber grating sensor. It is a figure which shows the example which provides a cantilever protrusion in a wing | blade and provides a fiber grating part. It is a figure which shows the example which forms a cantilever protrusion in a wing | blade. It is a figure which shows the various aspects of a cantilever protrusion. It is a principle figure of FORJ. It is a figure which shows a prior art example. It is a figure which shows the example which provided the conventional dielectric barrier discharge apparatus in the wing | blade.

  Embodiments of the present invention will be described with reference to the drawings. The present invention uses the blade surface flow control technology using plasma by dielectric barrier discharge previously proposed by the present inventors as shown in FIG. 9, and in particular, the sensor 59 includes various rotor blades and Since it has been developed for use in a wide range of fixed blades and is particularly suitable for a rotor blade of a wind power generation system, a separation detection sensor as a sensor used in the present invention will be described first.

  The peeling detection sensor used in the present invention is a cantilever type detection system as shown in FIG. 2, for example, and is a strain detection system using a broadband laser. In this system, a plurality of strains can be detected by FBG using a single optical fiber.

  This FBG is an abbreviation for Fiber Bragg Grating Sensor, and is a technology widely called a fiber grating sensor. This is because slits at equal intervals are placed in an optical fiber at high density by an ultraviolet laser or the like, and the wavelength at which the broadband laser is reflected changes according to the slit interval that changes depending on external force, ambient temperature, and the like. The amount of distortion can be analyzed from the amount of change. By installing several sensor sections with different slit intervals in a single fiber, distortion at different locations can be measured simultaneously.

  The broadband laser introduced from the start point of the fiber is introduced into the FBG sensor part A. Since the sensor A is provided with about 2000 slits in an area of about 10 mm in advance at an interval of L, the laser wavelength Among them, the wavelength of 1B = 2n0L is reflected. It is known that the slit interval L changes to L + L ′ when strain is applied, but is proportional to the strain. If a calibration curve of the strain and the reflection wavelength 1B is obtained in advance, the measured reflection wavelength 1B1 = 2n0. (L + L ′) can be read as an external force applied as a strain to the sensor.

  The advantage of the FBG sensor is not only that it can avoid problems such as electromagnetic noise and electric leakage, but also that it is possible to combine a plurality of sensor parts having slit intervals different from L in addition to the part of sensor A in the same fiber. For example, if the FBG sensor B of FIG. 3 is installed in a portion that is not subjected to deformation due to strain, it can be used as a reference “temperature sensor” that detects deformation of the fiber due to temperature change.

  Since the reflected wavelength of the FBG sensor A also appears as both external force and temperature distortion due to changes in ambient temperature, temperature drift can be corrected by monitoring the temperature change by installing the FBG sensor B in the vicinity of the sensor A. . As a result, the external force applied to the sensor A can be more accurately evaluated.

  In the cantilever type FBG sensor shown in FIG. 4 using the FBG sensor as described above, the cantilever projection 31 is projected from the blade 2 along a normal air flow, and the optical fiber 13 is allowed to run along the projection. At that time, when the FBG sensor A26 is bonded to the base of the cantilever projection 31 and is U-turned at the cantilever projection 31 portion and guided outside, the FBG along the surface of the wing 2 Sensor B26 is attached.

  When such a cantilever projection 31 is attached to an actual rotor blade such as a windmill, it can be attached as shown in FIG. 3B, for example. In the example of the figure, a schematic diagram of three wind turbines is shown, one cantilever projection similar to that shown in FIG. 4A is provided on each of the three blades, and the same FBG sensor as described above. A and FBG sensor B are arranged. These cantilever projections are connected by a single optical fiber. Therefore, in the illustrated example, six FBGs are arranged in series in one optical fiber. Therefore, there is only one fiber inlet / outlet portion 27 from the center of the rotor blade. In addition to the above example, one fiber inlet / outlet may be provided for each blade.

  When the cantilever type sensor is attached to the wing, various methods can be used. FIG. 5A shows an example in which the cantilever protrusion is formed integrally with the wing. Such molding can be performed by using a machining center, a 3D printer, or the like so that an airfoil including a sensor unit can be made innocent. In the example shown in FIG. 5B, the adapter 41 is integrally formed with a cantilever projection as described above so that the sensor portion can be damaged or deteriorated, and the cantilever projection is formed in a predetermined position on the blade 42 in advance. You may shape | mold by inserting and fixing in the formed groove | channel.

  Further, as shown in FIG. 6, for example, various cantilever projections are formed and prepared as sensor pieces of the same size, and a desired sensor can be formed by arbitrarily combining them. Anyway. In the example of FIG. 5A, a sensor piece 46A having a large cantilever projection along the main flow direction and a relatively small cantilever projection for detecting a flow in the reverse flow direction are provided. The example which combined the sensor piece is shown.

  FIG. 6B shows an example installed in the opposite direction to FIG. 6A, and these sensor pieces 47A and 47B are not newly made and are arranged using those of FIG. 6A. It is possible to cope with it simply by changing. In the example of FIG. 5C, an example is shown in which cantilever protrusions 48A and 48B having the same shape in opposite directions are used facing each other. The sensor pieces as described above can be used in any combination and in any number, and by providing the FBG sensors as described above on these cantilever projections, for example, as shown in FIG. It can be implemented in various ways. Note that when FBG sensors are arranged in series on a single optical fiber, 20 or more FBGs can be used at present.

  When the FBG sensor is attached to the cantilever projection as described above and used as a peeling sensor, it can be used by being connected in series with a single optical fiber as shown in FIG. When this blade is a rotating blade, such as a windmill, when analyzing the data of each FBG sensor using the reflected wave of the optical fiber, the analysis part exists on the fixed side, so the rotating optical joint is in between. Must be used. For that purpose, it can solve by using FORJ (fiber optics rotary joint) widely used conventionally.

  The principle of this FORJ is shown in FIG. In this FORJ, the fixed-side lens 32 and the rotation-side lens 33 are placed facing each other so as to be parallel rays, and the light from the light introducing portion 34 of the optical fiber is made of the lens as described above. The light is derived from the light deriving unit 35 through the light rotation joint unit. In such a FORJ, light transmission loss occurs as shown in the figure, so care must be taken when multichanneling is performed.

As described above, by fixing the FBG sensor provided on the optical fiber to the cantilever protrusion provided on the wing, it is possible to reliably measure the peeling phenomenon generated in the wing, and the dielectric provided on the wing by the sensor signal. An example in which this system is applied to a wind turbine of wind power generation is shown in FIG. 1, which can control energization of the barrier discharge device and adjust aerodynamic characteristics of the blade surface corresponding to separation.

  In the example of the wind turbine 1 of the wind power generation shown in FIG. 1, a support shaft 4 is provided via a horizontal rotating member 5 that rotates in accordance with the wind direction with respect to the fixed shaft 3 that supports the entire wind turbine. 1 main part is supported. The rotary shaft 7 is rotatably supported by the support shaft bearing, and the rotary shaft 7 is connected to the base of the rotary blade 2.

  For example, the rotating blade 2 has a pair of a sensor unit including an FBG sensor A for measuring the strain of the cantilever and an FBG sensor B for referring to the ambient temperature on the cantilever projection as shown in FIG. Is fixed. Since these sensor units rotate, the light from the FBG sensor is guided to the optical fiber on the fixed side via the FORJ 15 as described above, and the state of separation on the blade is detected by analyzing the light.

  In the example shown in FIG. 1, the secondary coil 12 is provided on the rotating shaft, the electric power from the wind power generation system is guided to the primary coil 13, taken into the rotating secondary coil 12, and supplied to the rechargeable battery 16. Charge the required amount. As a result, a dielectric barrier discharge power source is used, and a high frequency power source for induction barrier discharge is controlled as shown in FIG. 8 in accordance with a peeling detection signal from the FBG sensor.

  The above control system is shown in FIG. 1B. When the FBG sensor 14 detects peeling or the like and transmits this to the fixed side FBG data analysis unit 16 by the optical fiber 8, as described above, the optical rotation joint is used. Is transmitted via HORJ9. On the other hand, the rechargeable battery 7 is charged with the current from the general power supply system 17 by the dielectric power supply unit 6 including the primary coil and the secondary coil.

  In the high-frequency applied voltage control unit 8, high-frequency control is performed by the power source of the rechargeable battery 7 based on the signal from the FBG data analysis peeling detection unit 16, discharge control of the dielectric barrier discharge unit 35 is performed, and the output of the FBG sensor 14 is supported. In addition, a signal and power can be transmitted between the rotating side and the stationary side, and an anti-peeling action can be performed.

DESCRIPTION OF SYMBOLS 1 Windmill 2 Wing | blade 3 Fixed axis | shaft 4 Support axis | shaft 5 Horizontal rotating member 6 Plasma power supply part 7 Rotating shaft 8 High frequency applied voltage control part 9 FORJ
DESCRIPTION OF SYMBOLS 10 Cone 11 Power transmission mechanism 12 Secondary coil 13 Primary coil 14 Peel sensor 15 Dielectric barrier discharge part 16 FBG data analysis peel detector 17 General power supply system

Claims (8)

A cantilever projection that protrudes to receive the fluid around the wing; and
An optical fiber having a fiber grating portion fixed to the cantilever projection;
By analyzing light data from the fiber grating part of the optical fiber, a data analysis part for detecting distortion of the cantilever projection,
A dielectric barrier discharge portion fixed to the wing;
A high-frequency voltage control unit for controlling a high-frequency voltage supplied to the dielectric barrier discharge unit,
The high-frequency voltage control unit controls the high-frequency voltage supplied to the dielectric barrier discharge unit according to the data analysis result of the data analysis unit.   2. The other fiber grating part for data reference is fixed at a position close to the fiber grating part fixed to the cantilever protrusion and not affected by the distortion of the cantilever protrusion. An aerodynamic control wing device using dielectric barrier discharge as described. The wing is a rotary wing;
2. The rotating-side optical fiber connected to a fiber grating portion that rotates together with a wing by being fixed to the cantilever projection is connected to a fixed-side optical fiber so as to be able to transmit and receive data by an optical fiber rotating joint. An aerodynamic control wing device using dielectric barrier discharge as described. The wing is a rotary wing;
The power supplied to the dielectric barrier discharge unit is supplied from the fixed side by supplying current from the primary coil provided on the fixed side to the secondary coil that is fixed to the shaft of the rotor blade and rotates in the vicinity of the primary coil. 4. The aerodynamic control blade device using dielectric barrier discharge according to claim 3, wherein a battery provided on the rotating side is charged.   2. The dielectric barrier discharge utilizing aerodynamic control wing device according to claim 1, wherein all of the fiber grating portions fixed to the cantilever projections are connected in series by one optical fiber.   2. The dielectric barrier discharge utilizing aerodynamic control wing device according to claim 1, wherein the cantilever projection is formed integrally with the wing.   2. The cantilever protrusion is formed integrally with a member constituting a part of the wing, and a predetermined wing is formed by fixing a part of the wing to the wing body. An aerodynamic control wing device using dielectric barrier discharge as described.   2. The dielectric barrier discharge utilizing aerodynamics according to claim 1, wherein each of the cantilever protrusions is composed of members having different cantilever protrusion shapes, and the members can be used in any combination. Control device.

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