CN117189471A - Vaneless wind power generation device capable of actively controlling karman vortex street and control method thereof - Google Patents
Vaneless wind power generation device capable of actively controlling karman vortex street and control method thereof Download PDFInfo
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02E10/00—Energy generation through renewable energy sources
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Abstract
The invention relates to the technical field of wind power generation, in particular to a bladeless wind power generation device capable of actively controlling karman vortex street and a control method thereof. The invention relates to a bladeless wind power generation device for actively controlling karman vortex street, which comprises a frame, a swinging rod, an energy conversion mechanism and a swinging frequency adjusting mechanism; a plurality of vibrators are symmetrically arranged on the swing rod in the circumferential direction; the lower end of the swinging rod is hinged to the frame, and the energy conversion mechanism is used for converting mechanical energy of the swinging rod into electric energy; the swing frequency adjusting mechanism is used for adjusting the swing frequency of the swing rod. According to the invention, the vibrator at a specific position on the swinging rod is controlled to generate specific deformation, and the karman vortex street can be excited at different wind speeds, so that the wind speed range of the bladeless wind power generation device for generating electricity is widened, and the wind energy utilization rate is improved.
Description
Technical Field
The invention relates to the technical field of wind power generation, in particular to a bladeless wind power generation device capable of actively controlling karman vortex street and a control method thereof.
Background
The energy problem has been an important issue restricting the development of human society. With the increasing severity of the energy shortage in the society today, the search for new energy is also advancing.
Wind energy is favored by people as clean, pollution-free, inexhaustible energy. The wind energy is huge, and the global wind energy is about 2.74 multiplied by 10 9 MW, wherein available wind energy is 2X 10 7 MW. By 2030 the installed U.S. wind power capacity is expected to increase to 3.04 hundred million kilowatts, which will meet 20% of the power demand. Wind power has been 20% of the total electricity in the united kingdom 2019, and wind power is expected to supply over 50% of the electricity in the united kingdom by 2030. Therefore, wind power will keep growing at a high speed in the world in the future, and large-scale development of wind power is a necessary trend.
The amount of power generation of a traditional wind driven generator with blades depends on the size of the blades, for example, the length of the blades of a 1.5MW wind driven generator is generally 40 meters, and the diameter of a wind wheel reaches 100 meters. Therefore, the traditional wind turbine can only spread widely, and needs a very large land occupation ratio, and the rotation of the traditional wind turbine not only affects the flying of birds, but also brings great interference to communication electric waves. The transportation, installation, maintenance and the like of the huge equipment are all huge items of cost and labor consumption. In addition, the alternating dynamic load caused by wind shear under the large wind wheel diameter can cause uneven stress of the blades if mishandling is carried out, so that the load of the blade root is increased, and the reliability and the service life of the wind driven generator are affected.
The blade-free wind power generation device is a device for generating power based on the Karman vortex street theory, and the working principle is that the Karman vortex street effect formed in wake flow of air passing through objects such as cylinders is utilized to drive a generator to generate power, and the blades in the traditional wind power generation set are not needed, so that the production, transportation, maintenance and operation cost can be greatly saved. The authoritative person's large Weiya fresnel (David Yanez) estimates that the cost of converting kinetic energy of a bladeless wind power generation device into electrical energy is about 30% of that of a traditional bladed wind power machine, and the maintenance cost is about 80%, the running cost is about 51% and the production cost is about 53%.
Under certain conditions, when the original uniform and stable incoming flow bypasses the object, the vortex which is turned to the opposite direction is periodically dropped on two sides of the object, and the vortex is formed in a regular staggered state at the rear part of the object. The first person to systematically explain this phenomenon is the well-known aerodynamic Von Karman (Von Karman) and is named Karman vortex street because the vortices are regularly staggered on both sides of the trail just like street lamps on both sides of the street.
Whether or not a karman vortex street appears at the rear of the object depends mainly on the reynolds number Re of the flow, and regular karman vortex streets appear only when the reynolds number is in a certain range (see fig. 8).
Wherein ρ and μ are fluid density and dynamic viscosity, v is incoming flow velocity, and d is characteristic length.
The existing bladeless wind power generation devices are all passive, that is, only if the wind speed reaches a certain value, karman vortex street can be formed and power generation can be performed. Fig. 9 is a graph of the power of the wind power generator published in j.energy 2014,7 (4), 2676-2700, and it can be seen from fig. 9 that the conventional bladeless wind power generator can generate power only in a narrow wind speed range.
In addition, in order to stabilize the power generation amount of the bladeless wind power generation device, the karman vortex street generated by the bladeless wind power generation device must be stable. Von karman gives the precondition for karman vortex street stabilization to b/a= 0.2805, where b is the distance between two vortex trains and a is the distance between adjacent vortices in the same vortex train. The existing passive bladeless wind power generation device cannot meet the necessary condition for stabilizing karman vortex street, and cannot guarantee the stability of generated energy.
Disclosure of Invention
The invention aims to provide a bladeless wind power generation device capable of actively controlling karman vortex street, which can excite the karman vortex street under different wind speeds by controlling a vibrator at a specific position on a swinging rod to generate specific deformation, so that the wind speed range of the bladeless wind power generation device for generating electricity is widened, and the wind energy utilization rate is improved.
In order to achieve the above purpose, the present invention adopts the following technical scheme: a bladeless wind power generation device for actively controlling karman vortex street comprises a frame, a swinging rod, an energy conversion mechanism and a swinging frequency adjusting mechanism; a plurality of vibrators are symmetrically arranged on the swing rod in the circumferential direction; the lower end of the swinging rod is hinged to the frame, and the energy conversion mechanism is used for converting mechanical energy of the swinging rod into electric energy; the swing frequency adjusting mechanism is used for adjusting the swing frequency of the swing rod.
Compared with the prior art, the vaneless wind power generation device for actively controlling karman vortex street has the beneficial effects that: (1) The vibrator at a specific position on the swinging rod is controlled to generate specific deformation, so that karman vortex street can be excited at different wind speeds, the wind speed range of the bladeless wind power generation device for generating electricity is widened, and the wind energy utilization rate is improved. (2) The boundary layer separation can be promoted by controlling the vibration frequency and the vibration amplitude of the vibrator on the lee side of the swinging rod, so that the frequency of the karman vortex street is controlled, the distance between adjacent vortices in the same vortex row is further controlled, the necessary condition of the stability of the karman vortex street is met, and the stability of the generated energy is ensured. (3) By controlling the vibration frequency and the vibration amplitude of the vibrator on the windward side of the swinging rod, the vortex quantity in the boundary layer can be increased, so that the swinging amplitude of the swinging rod is enhanced, and the generated energy is increased. (4) The oscillating frequency of the oscillating rod is adjusted through the oscillating frequency adjusting mechanism, so that the oscillating frequency of the oscillating rod is consistent with the frequency of the karman vortex street, the resonance effect is achieved, and the energy is absorbed better. (5) The diameter of a wind wheel of the existing wind driven generator with blades can reach hundreds of meters, so that the wind driven generator with blades can only spread widely to avoid mutual interference, and a very large land occupation rate is required; the Karman vortex street towed by the bladeless wind power generation device provides a vibration source for the adjacent bladeless wind power generation device, so that the bladeless wind power generation device can be distributed in a quite small range, thereby saving space and increasing the generated energy.
Preferably, the vibrator is a piezoelectric ceramic bar. By applying an electric field in the polarization direction of the piezoelectric ceramic strips by the inverse piezoelectric effect, the piezoelectric ceramic strips can be mechanically deformed.
Preferably, the swing frequency adjusting mechanism comprises an extension rod, a balancing weight and a balancing weight driving mechanism, wherein the extension rod is fixedly connected to the lower end of the swing rod and extends downwards, the balancing weight is slidably mounted on the extension rod, and the balancing weight driving mechanism is used for driving the balancing weight to slide on the extension rod. The balancing weight driving mechanism drives the balancing weight to slide on the extension rod, so that the mass center of a system formed by the swinging rod and the swinging frequency adjusting mechanism can be changed, and the swinging frequency of the swinging rod can be adjusted.
In order to obtain the wind speed and the wind direction, it is preferable to further include an anemometer mounted at an upper end of the swing lever.
Preferably, the energy conversion mechanism comprises a connecting rod, a rack, a driving gear, a first driven gear, a second driven gear, an idler gear, a first ratchet mechanism, a second ratchet mechanism and a generator; the rack is slidably arranged on the rack, and the connecting rod is respectively hinged with the swinging rod and the rack; the driving gear, the first driven gear, the second driven gear and the idler gear are all rotatably arranged on the frame; the driving gear is meshed with the rack, the idler gear and the second driven gear respectively, and the idler gear is meshed with the first driven gear; the first driven gear can drive the input shaft of the generator to rotate in the positive direction through the first ratchet mechanism, and the second driven gear can drive the input shaft of the generator to rotate in the positive direction through the second ratchet mechanism. By adopting the technical scheme, the frame, the swinging rod, the connecting rod and the rack form a rocker sliding block mechanism, the reciprocating swing of the swinging rod is converted into the reciprocating movement of the rack through the connecting rod, and the reciprocating movement of the rack is converted into the forward rotation of the input shaft of the generator through the driving gear, the first driven gear, the second driven gear, the idler gear, the first ratchet mechanism and the second ratchet mechanism.
In order to increase the swing amplitude of the swing rod caused by karman vortex street, the swing inertia of the swing rod should be reduced as much as possible, and preferably, the swing rod is made of carbon fiber or glass fiber reinforced plastic.
The invention also provides a control method of the bladeless wind power generation device for actively controlling the karman vortex street, which comprises the following steps:
s1, setting an experimental model with the swing rod reduced in equal proportion in a wind tunnel, wherein a flowing particle observer is arranged in the wind tunnel, and the diameter of the experimental model is d';
s2, starting a wind tunnel, controlling the wind speed of the wind tunnel to be v', controlling the wind direction to be the initial wind direction, respectively changing the position of the vibrator and the deformation of the vibrator, and recording the position of the vibrator and the deformation of the vibrator when the karman vortex street is observed through the flow particle observer;
s3, keeping v' in the S2 unchanged, selecting a plurality of wind directions, and repeating the S2;
s4, selecting a plurality of different v 'S, and repeating the steps S2 and S3 respectively to obtain a relation matrix of v' S, the positions of the wind direction and the vibrator and the deformation of the vibrator;
s5, throughV is used for replacing v', a relation matrix of v, wind direction, the position of the vibrator and the deformation of the vibrator is obtained, wherein v is the wind speed when the bladeless wind power generation device actively controlling karman vortex street generates electricity, and d is the diameter of the swinging rod;
s6, when the bladeless wind power generation device actively controlling the karman vortex street generates power, acquiring wind speed v and wind direction, and referring to a relation matrix of the v, the wind direction, the position of the vibrator and the deformation of the vibrator, and controlling the vibrator to excite the karman vortex street; the swinging frequency of the swinging rod is adjusted through the swinging frequency adjusting mechanism, so that the swinging frequency of the swinging rod is identical to the frequency of the karman vortex street.
Preferably, in S2, when karman vortex street is observed by the flow particle observer and b/a= 0.2805 is satisfied, the position, phase, amplitude and frequency of the vibrator at this time are recorded, where b is the distance between two vortices and a is the distance between adjacent vortices in the same vortex. By adopting the technical scheme, the stability of the generated energy can be ensured.
Drawings
Fig. 1 is a schematic diagram of a bladeless wind power generation device for actively controlling karman vortex street in embodiment 1.
Fig. 2 is a cross-sectional view of the swing lever in embodiment 1.
Fig. 3 is a partial enlarged view of a portion a in fig. 2.
Fig. 4 is a schematic structural diagram of the energy conversion mechanism in embodiment 1.
Fig. 5 is a schematic structural diagram of the wobble frequency adjusting mechanism in embodiment 1.
Fig. 6 is a schematic structural diagram of a wind tunnel for controlling the generation and development of karman vortex street in example 1.
Fig. 7 is a schematic view of the structure of a wind tunnel for controlling the generation and development of karman vortex street in example 2.
FIG. 8 shows the cylindrical surface flow spectrum and flow topology changes for different Reynolds numbers.
FIG. 9 is a graph showing the wind speed range of the passive karman vortex street power generation published in the prior art.
Wherein: 1-frame, 2-swinging rod, 3-vibrator, 4-extension rod, 5-balancing weight, 6-anemometer, 7-connecting rod, 8-rack, 9-driving gear, 10-first driven gear, 11-second driven gear, 12-idler, 13-generator, input shaft of 14-generator, 15, piezoceramic strip, 16-first ball bearing, 17-second ball bearing, 18-third ball bearing, 19-longitudinal rib, 20-transverse spacer frame, 21-motor, 22-lead screw, 23-nut, 24-ratchet, 25-ratchet, 26-experimental model, 27-flow particle observer, 28-motor, 29-electrode, 30-wind tunnel upper wall, 31-wind tunnel lower wall, 32-wind tunnel side wall, 33-reflecting plate, 34-observation window, 35-wind tunnel side window
Detailed Description
The following examples are further illustrative of the invention, but the invention is not limited thereto.
Example 1
As shown in figure 1, the bladeless wind power generation device for actively controlling karman vortex street comprises a frame 1, a swinging rod 2, an energy conversion mechanism, a swinging frequency adjusting mechanism and a wind speed anemoscope 6.
The lower end of the swinging rod 2 is hinged to the frame 1 through a first ball bearing 16, so that the swinging rod 2 can swing along any direction of the center point of the first ball bearing 16 under the excitation of karman vortex street. In order to increase the swing amplitude of the swing rod 2 caused by karman vortex street, the swing inertia of the swing rod 2 should be reduced as much as possible, based on this, the swing rod 2 is designed to be cylindrical, and is made of carbon fiber or glass fiber reinforced plastic, and the inside is reinforced by a longitudinal rib 19 and a transverse bulkhead 20, so as to ensure enough bending and torsional rigidity.
The oscillation frequency adjusting mechanism is used for adjusting the oscillation frequency of the oscillating bar 2. Specifically, as shown in fig. 5, the oscillating frequency adjusting mechanism includes an extension rod 4, a balancing weight 5 and a balancing weight driving mechanism, the extension rod 4 is fixedly connected to the lower end of the oscillating rod 2 and extends downwards, the balancing weight 5 is slidably mounted on the extension rod 4, and the balancing weight driving mechanism is used for driving the balancing weight 5 to slide on the extension rod 4. The balancing weight driving mechanism of the embodiment comprises a motor 21, a screw 22 and a nut 23, wherein the motor 21 is arranged on the frame 1, an output shaft of the motor 21 is connected with the screw 22, the nut 23 is fixedly arranged on the balancing weight 5 and is in threaded fit with the screw 22, the motor 21 drives the screw 22 to rotate, and then the balancing weight 5 is driven to move along the extension rod 4 through the nut 23.
According to the theory of simple pendulum stability, the center of mass of the system of the oscillating bar 2 and the oscillating frequency adjusting mechanism should be below the center of the first ball bearing 16, and the oscillation period T is:
where L is the distance from the center of mass of the system (the center of mass of the counterweight) to the center of the first ball bearing 16 and g is the gravitational acceleration. By adjusting the height of the balancing weight 5, the swing period of the swing rod 2 can be adjusted, so that the swing period is as close to the vibration frequency of the karman vortex street as possible, and the maximum resonance effect is obtained.
The energy conversion mechanism is used for converting mechanical energy of the swing rod 2 into electric energy. Specifically, as shown in fig. 4, the energy conversion mechanism includes a link 7, a rack 8, a driving gear 9, a first driven gear 10, a second driven gear 11, an idler gear 12, a first ratchet mechanism, a second ratchet mechanism, and a generator 13. The rack 8 is slidably mounted on the frame 1, the upper end of the connecting rod 7 is hinged with the extension rod 4 through a second ball bearing 17, and the lower end of the connecting rod 7 is hinged with the rack 8 through a third ball bearing 18. The driving gear 9, the first driven gear 10, the second driven gear 11 and the idle gear 12 are all rotatably mounted on the frame 1. The driving gear 9 is meshed with the rack 8, the idler gear 12 and the second driven gear 11 respectively, and the idler gear 12 is meshed with the first driven gear 10. The first ratchet mechanism and the second ratchet driving mechanism have the same structure and comprise a ratchet 24 and a ratchet 25. The first driven gear 10 can drive the input shaft 14 of the generator to rotate in the forward direction through a first ratchet mechanism, and the second driven gear 11 can drive the input shaft 14 of the generator to rotate in the forward direction through a second ratchet mechanism.
The frame 1, the swinging rod 2, the connecting rod 7 and the rack 8 form a rocker sliding block mechanism, and the reciprocating swinging of the swinging rod 2 is converted into the reciprocating movement of the rack 8 through the connecting rod 7. When the rack 8 moves upwards, the driving gear 9 is driven to rotate in the forward direction, the driving gear 9 drives the idle gear 12 to rotate in the reverse direction, the idle gear 12 drives the first driven gear 10 to rotate in the forward direction, and the first driven gear 10 drives the input shaft 14 of the generator to rotate in the forward direction through the first ratchet mechanism; at the same time, the driving gear 9 drives the second driven gear 11 to rotate in the opposite direction, and the ratchet 25 of the second ratchet mechanism does not exert a force on the ratchet 24, so that the second driven gear 11 does not exert a force on the input shaft 14 of the generator. When the rack 8 moves downwards, the driving gear 9 is driven to rotate reversely, the driving gear 9 drives the second driven gear 11 to rotate positively, and the second driven gear 11 drives the input shaft 14 of the generator to rotate positively through the second ratchet mechanism; at the same time, the driving gear 9 drives the idler gear 12 to rotate in the forward direction, and the idler gear 12 drives the first driven gear 10 to rotate in the reverse direction, and at this time, the ratchet 25 of the first ratchet mechanism does not exert a force on the ratchet 24, so that the first driven gear 10 does not exert a force on the input shaft 14 of the generator. In this way, the reciprocating swing of the swing lever 2 always drives the input shaft 14 of the generator to rotate in the forward direction.
As shown in fig. 2, the oscillating rod 2 is provided with a plurality of vibrators 3 symmetrically in the circumferential direction. In this embodiment, the vibrator 3 extends on the outer circumferential surface of the oscillating rod 2 in a direction parallel to the axial direction thereof, as shown in fig. 3, each five piezoelectric ceramic strips 15 are stacked in the radial direction of the oscillating rod 2 to form a vibrator, and electrodes 29 are disposed at both ends of the piezoelectric ceramic strips 15. By applying an electric field in the polarization direction of the piezoelectric ceramic strip 15 by the inverse piezoelectric effect, the piezoelectric ceramic strip 15 can be mechanically deformed; by applying different voltages, the deformation amplitude of the piezoelectric ceramic strip 15 can be controlled. Those skilled in the art will appreciate that other micro-vibrators may be used for the vibrator 3.
The anemoclinograph 6 is arranged at the upper end of the swinging rod 2 and is used for acquiring wind speed and wind direction, and further, the corresponding vibrator 3 is excited to vibrate through the control circuit, and the karman vortex street is excited.
The up-down sliding range of the rack 8 depends on the length l of the extension rod 4 1 Length l of connecting rod 7 2 Sum pendulumDeflection angle theta of movable rod 2 1 And can be calculated from the following formula:
ΔL＝(l 1 +l 2 )-l 1 cosθ 1 -(l 2 2 -(l 1 ×sinθ 1 2 )) 1/2
properly adjust l 1 And l 2 The moving range of the slide bar can be enlarged as much as possible, thereby increasing the generating capacity.
In the embodiment, the bladeless wind power generation device for actively controlling karman vortex street has low requirements on sites, and can be installed in mountain areas, deserts, rivers and oceans.
It will be appreciated by those skilled in the art that the same principle of the bladeless wind power generation device of the present embodiment for actively controlling karman vortex street can be used to generate electricity by water flow.
The embodiment also provides a control method of the bladeless wind power generation device for actively controlling karman vortex street, which comprises the following steps:
s1, arranging the experimental model 26 with the swinging rod 2 reduced in equal proportion in a wind tunnel, wherein the wind tunnel is of a cuboid structure formed by a wind tunnel upper wall 30, a wind tunnel lower wall 31 and a wind tunnel side wall 32, and the left end of the wind tunnel is an air inlet, and the right end of the wind tunnel is an air outlet as shown in FIG. 6. The wind tunnel side wall 32 is provided with a wind tunnel side window 35, the wind tunnel upper wall 30 is provided with an observation window 34, and a flowing particle observer 27 (PIV system) is arranged at the observation window 34 for observing the occurrence and development of karman vortex street. Reflection plates 33 are arranged at the upper end and the lower end of the experimental model 26 so as to reduce the influence of the boundary layer of the wind tunnel wall. A motor 28 for driving the experimental model 26 to rotate around the axis of the experimental model is arranged in the wind tunnel. The experimental model 26 has a diameter d'.
S2, starting a wind tunnel, controlling the wind speed v' of the wind tunnel to be 5m/S, controlling the experimental model 26 to be an initial angle through the motor 28, respectively changing the position of the vibrator 3 and the deformation of the vibrator 3, and recording the position, the phase, the amplitude and the frequency of the vibrator 3 when the karman vortex street is observed through the flow particle observer 27 and b/a= 0.2805 is met.
Wherein b is the distance between two vortex trains, a is the distance between adjacent vortices in the same vortex train, b/a= 0.2805 is the necessary condition for von Karman to obtain Karman vortex street stabilization, and the stabilization of the generated energy can be ensured by meeting the condition. By controlling the vibration frequency and amplitude of the vibrator 3 on the lee side of the oscillating bar 2, boundary layer separation can be promoted, thereby controlling the frequency of karman vortex streets and further controlling the distance between adjacent vortices in the same vortex train.
S3, keeping v 'in S2 unchanged, namely v' is 5m/S, sequentially controlling the experimental model 26 to rotate forward by 5 degrees, 10 degrees and 15 degrees … … relative to the initial position through the motor 28 so as to simulate different wind directions, and repeating S2 under the condition;
s4, selecting v 'to be 10m/S and 15m/S … …, and repeating S2 and S3 respectively to obtain a relation matrix of v' and the position, phase, amplitude and frequency of the vibrator 3.
S5, throughV is used for replacing v', a relation matrix of v, wind direction and position, phase, amplitude and frequency of the vibrator 3 is obtained, wherein v is wind speed when the bladeless wind power generation device actively controlling karman vortex street generates electricity, and d is the diameter of the swinging rod 2.
Since the experimental model 26 is obtained by scaling down the swing lever 2, v needs to be obtained by conversion. Whether or not a karman vortex street appears at the rear of the object is mainly dependent on the reynolds number Re of the flow, and regular karman vortex streets can only appear when the reynolds number is in a specific range.
Where ρ and μ are the fluid density and dynamic viscosity, respectively, v is the incoming flow velocity, and l is the characteristic length, in this embodiment l can be considered as d, d'.
In wind tunnel experiments and actual power generation, ρ and μ can be regarded as constants, so that Re can be ensured to be the same only by meeting vd=v'd'.
S6, when the vaneless wind power generation device actively controlling the karman vortex street generates power, obtaining wind speed v and wind direction through an anemoscope 6, and referring to a relation matrix of the v, the wind direction, the position of the vibrator 3 and the deformation of the vibrator 3, so as to control the vibrator 3 to excite the karman vortex street; the oscillating frequency of the oscillating rod 2 is adjusted through the oscillating frequency adjusting mechanism, so that the oscillating frequency of the oscillating rod 2 is the same as the frequency of the karman vortex street, the resonance effect is achieved, and energy is absorbed better.
Example 2
The diameter of the wind wheel of the existing wind driven generator with blades can reach hundreds of meters, so that the wind driven generator with blades can only spread widely to avoid mutual interference, and a very large land occupation rate is required. The Karman vortex street towed by the bladeless wind power generation device provides a vibration source for the adjacent bladeless wind power generation devices, so that the beneficial interference of the Karman vortex street among the bladeless wind power generation devices is utilized, and therefore, the Karman vortex street can be distributed in a quite small range, the space is saved, and the generated energy is increased.
As shown in fig. 7, in the wind tunnel of the present embodiment, the experimental models 26 are arranged in a square array, that is, four experimental models 26 are uniformly distributed along the same circumference, and the motor 28 is used to drive the four experimental models 26 to rotate with the center of the circumference where they are located as an axis.
The wind tunnel in the present embodiment is directed to a square array of bladeless wind power generation devices, and is used for obtaining a relation matrix of wind speed, wind direction and position, phase, amplitude and frequency of the vibrator 3.
In some other embodiments, the experimental models 26 in the wind tunnel may also take other forms of arrays, such as pentagons, circles, diamonds, and the like.
The above examples are only illustrative of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention, and various modifications and improvements made by those skilled in the art to the technical solution of the present invention should fall within the scope of protection defined by the claims of the present invention without departing from the spirit of the present invention.
Claims (8)
1. The bladeless wind power generation device for actively controlling karman vortex street is characterized by comprising a frame (1), a swinging rod (2), an energy conversion mechanism and a swinging frequency adjustment mechanism; a plurality of vibrators (3) are symmetrically arranged on the swinging rod (2) in the circumferential direction; the lower end of the swinging rod (2) is hinged to the frame (1), and the energy conversion mechanism is used for converting mechanical energy of the swinging rod (2) into electric energy; the swing frequency adjusting mechanism is used for adjusting the swing frequency of the swing rod (2).
2. The vaneless wind power generating device of claim 1, wherein the vibrator is a piezo-ceramic strip (15).
3. The blade-free wind power generation device for actively controlling karman vortex street according to claim 1, wherein the swinging frequency adjusting mechanism comprises an extension rod (4), a balancing weight (5) and a balancing weight driving mechanism, the extension rod (4) is fixedly connected to the lower end of the swinging rod (2) and extends downwards, the balancing weight (5) is slidably mounted on the extension rod (4), and the balancing weight driving mechanism is used for driving the balancing weight (5) to slide on the extension rod (4).
4. The vaneless wind power generating device of claim 1, further comprising an anemometer (6), the anemometer (6) being mounted at an upper end of the oscillating bar (2).
5. The vaneless wind power generation device of claim 1, wherein the energy conversion mechanism comprises a connecting rod (7), a rack (8), a driving gear (9), a first driven gear (10), a second driven gear (11), an idler gear (12), a first ratchet mechanism, a second ratchet mechanism, and a generator (13); the rack (8) is slidably arranged on the frame (1), and the connecting rod (7) is respectively hinged with the swinging rod (2) and the rack (8); the driving gear (9), the first driven gear (10), the second driven gear (11) and the idler gear (12) are rotatably arranged on the frame (1); the driving gear (9) is respectively meshed with the rack (8), the idler gear (12) and the second driven gear (11), and the idler gear (12) is meshed with the first driven gear (10); the first driven gear (10) can drive the input shaft (14) of the generator to rotate in the forward direction through a first ratchet mechanism, and the second driven gear (11) can drive the input shaft (14) of the generator to rotate in the forward direction through a second ratchet mechanism.
6. The blade-free wind power generation device for actively controlling karman vortex street according to any one of claims 1-5, wherein the swinging rod (2) is made of carbon fiber or glass fiber reinforced plastic.
7. A control method of the bladeless wind power generation apparatus for actively controlling karman vortex street according to any one of claims 1 to 6, comprising the steps of:
s1, setting an experimental model (26) with the same proportion of the swinging rod (2) reduced in a wind tunnel, wherein a flowing particle observer (27) is arranged in the wind tunnel, and the diameter of the experimental model (26) is d';
s2, starting a wind tunnel, controlling the wind speed of the wind tunnel to be v', controlling the wind direction to be the initial wind direction, respectively changing the position of the vibrator (3) and the deformation of the vibrator (3), and recording the position of the vibrator (3) and the deformation of the vibrator (3) when the karman vortex street is observed through a flow particle observer (27) observer;
s3, keeping v' in the S2 unchanged, selecting a plurality of wind directions, and repeating the S2;
s4, selecting a plurality of different v 'S, and repeating the steps S2 and S3 respectively to obtain a relation matrix of v' S, the wind direction and the position of the vibrator (3) and the deformation of the vibrator (3);
s5, throughV is used for replacing v', so as to obtain a relation matrix of v, wind direction, the position of the vibrator (3) and the deformation of the vibrator (3), wherein v is the wind speed of the vaneless wind power generation device for actively controlling karman vortex street during power generation, and d is the diameter of the swinging rod (2);
s6, when the bladeless wind power generation device actively controlling the karman vortex street generates power, acquiring wind speed v and wind direction, and referring to a relation matrix of the v, the wind direction, the position of the vibrator (3) and the deformation of the vibrator (3), so as to control the vibrator (3) to excite the karman vortex street; the swinging frequency of the swinging rod (2) is regulated by the swinging frequency regulating mechanism, so that the swinging frequency of the swinging rod (2) is the same as the frequency of the karman vortex street.
8. The control method of the bladeless wind power generation apparatus actively controlling karman vortex street according to claim 7, characterized in that in S2, when the occurrence of karman vortex street is observed by a flow particle observer (27) and b/a = 0.2805 is satisfied, the position, phase, amplitude and frequency of the vibrator (3) at this time are recorded, where b is the distance between two vortices and a is the distance between adjacent vortices in the same vortex.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998012433A1 (en) * | 1996-09-20 | 1998-03-26 | Lee Arnold | Extraction of energy from flowing fluids |
| CN105386931A (en) * | 2014-09-09 | 2016-03-09 | 韩万龙 | High-altitude controlled Karman vortex street main and auxiliary wing kite wind power generation system |
| CN107061170A (en) * | 2017-02-21 | 2017-08-18 | 湘潭大学 | On-bladed wind-driven generator |
| CN108278180A (en) * | 2018-03-09 | 2018-07-13 | 杭州培聚教育科技有限公司 | On-bladed wind power generation plant based on vortex vibration and electromagnetic induction principle |
| CN108775272A (en) * | 2018-05-25 | 2018-11-09 | 东北大学 | A kind of no leaf formula generating system apparatus |
| CN110159477A (en) * | 2019-06-18 | 2019-08-23 | 国家电网有限公司 | A kind of marine power generation device |
| CN111188735A (en) * | 2018-11-15 | 2020-05-22 | 北京万源工业有限公司 | Blade-free wind generating set based on vortex-induced vibration principle |
| CN114542371A (en) * | 2022-02-17 | 2022-05-27 | 南京航空航天大学 | Wind power generation device utilizing vortex-induced vibration |
| US11712637B1 (en) * | 2018-03-23 | 2023-08-01 | Steven M. Hoffberg | Steerable disk or ball |
-
2023
- 2023-09-13 CN CN202311182242.2A patent/CN117189471A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998012433A1 (en) * | 1996-09-20 | 1998-03-26 | Lee Arnold | Extraction of energy from flowing fluids |
| CN105386931A (en) * | 2014-09-09 | 2016-03-09 | 韩万龙 | High-altitude controlled Karman vortex street main and auxiliary wing kite wind power generation system |
| CN107061170A (en) * | 2017-02-21 | 2017-08-18 | 湘潭大学 | On-bladed wind-driven generator |
| CN108278180A (en) * | 2018-03-09 | 2018-07-13 | 杭州培聚教育科技有限公司 | On-bladed wind power generation plant based on vortex vibration and electromagnetic induction principle |
| US11712637B1 (en) * | 2018-03-23 | 2023-08-01 | Steven M. Hoffberg | Steerable disk or ball |
| CN108775272A (en) * | 2018-05-25 | 2018-11-09 | 东北大学 | A kind of no leaf formula generating system apparatus |
| CN111188735A (en) * | 2018-11-15 | 2020-05-22 | 北京万源工业有限公司 | Blade-free wind generating set based on vortex-induced vibration principle |
| CN110159477A (en) * | 2019-06-18 | 2019-08-23 | 国家电网有限公司 | A kind of marine power generation device |
| CN114542371A (en) * | 2022-02-17 | 2022-05-27 | 南京航空航天大学 | Wind power generation device utilizing vortex-induced vibration |
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