JP4910134B2 - Self-supporting river monitoring device - Google Patents

Description

The present invention relates to a power self-supporting river monitoring apparatus suitable for monitoring a water flow or the like flowing through a river.

  In recent years, natural disasters caused by abnormal weather have frequently occurred. In particular, flood damage due to torrential rains that cause a large amount of rainfall in a limited area is increasing. In general, there are many small and medium-sized rivers in Japan, and if there is heavy rain in the upstream area of such small and medium rivers, the river flow increases within a short period of time, causing serious disasters such as levee breaks.

  In order to reduce the damage caused by such heavy rain, it is necessary to grasp the river flow rate and water level changes as early as possible. If possible, it is effective to acquire data in real time and take measures.

Such a real-time river monitoring system is already being implemented in relatively large first-class rivers (see, for example, Patent Document 1). However, real-time river monitoring systems are rarely implemented in small and medium-sized rivers because they are large and expensive. Even in the case of a first-class river, the current situation is that the amount of monitoring required is still insufficient.
JP 2002-256525 A

  Although establishment of a disaster prevention system by river monitoring is an urgent issue, it has not been realized in many small and medium-sized rivers because it can be expensive. Therefore, realization of a small and inexpensive river monitoring apparatus capable of performing stable river monitoring in a natural environment and performing highly reliable river monitoring is eagerly desired.

  In view of such circumstances, the inventor of the present invention has a structure that is simple and robust in operation principle and can be realized at low cost, and a programmable flow rate calculation from the output of the frequency detector. In addition, research was conducted on the issue of providing a river monitoring device that is highly reliable in the natural environment, small in size, and versatile with a low power consumption control device. In addition, by applying the vertical vortex excitation phenomenon, which is a new knowledge about fluid vibration, to a power generator, a power self-supporting river monitoring device that can operate stably in a river environment where power supply from a commercial power source is difficult is provided. This is the issue.

  According to the first aspect of the present invention, there is provided a ring that is disposed in a fluid, a support that supports the ring, and a drag that is disposed between the support and the fixed base and detects a drag that acts on the ring. A detector, a control device that processes a signal from the drag detector, and a power generation device that supplies electric power to the control device are provided.

The power supply self-supporting river monitoring device according to the first aspect of the present invention is the first columnar body in which the power generation device is disposed so that the longitudinal direction intersects the fluid flow direction; A second columnar body disposed to be separated from the columnar body and intersecting the longitudinal direction; and a vibration power generator disposed between the first columnar body and the fixed base. It is characterized by this.

According to a second aspect of the invention, in the power freestanding river monitoring device according to claim 1, wherein the vibration generator device is characterized in that an electromagnetic induction method.

According to a third aspect of the invention, characterized in that the power freestanding river monitoring device according to claim 1, wherein the vibration generator unit is a power generating apparatus comprising a pressing member for pressing the piezoelectric element and the piezoelectric element is there.

According to a fourth aspect of the present invention, in the power self-supporting river monitoring device according to any one of the first to third aspects, the drag detector is a strain gauge type detector.

The invention according to claim 5 is the power self-supporting river monitoring device according to any one of claims 1 to 4 , wherein the control device includes a transmitter for transmitting river monitoring information. is there.

A sixth aspect of the present invention is the power self-supporting river monitoring device according to any one of the first to fifth aspects, wherein the control device includes a display for displaying river monitoring information. is there.

A seventh aspect of the present invention is the power self-supporting river monitoring device according to any one of the first to sixth aspects, further comprising a capacitor for storing the power generated by the power generation device.

The invention according to claim 8 is the power self-supporting river monitoring device according to any one of claims 1 to 7 , wherein the fixed base is fixed in water.

A ninth aspect of the present invention is the power self-supporting river monitoring device according to any one of the first to seventh aspects, wherein the fixed base is levitated and moored on the water surface.

  According to the self-supporting river monitoring apparatus of the first aspect, the river can be monitored even in a place where the power grid is not maintained. In addition, a compact and inexpensive river monitoring device can be realized.

According to the power freestanding river monitoring device according to claim 1, it is possible to convert the fluid energy possessed by the flowing water of rivers power over a wide range of flow rates range, thereby improving the stability of the power supply.

According to the power self-supporting river monitoring device of the second aspect , since the main part of the power generation device is composed of the magnet and the coil, it is possible to perform highly reliable power generation over a long period.

According to the power self-supporting river monitoring device of the third aspect , since the power generation device includes the piezoelectric element and the pressing body that presses the piezoelectric element, a compact power generation device can be realized.

According to the power self-supporting river monitoring apparatus of the fourth aspect, the frequency of the ring excited by the vortex of the fluid can be easily detected as a resistance change of the strain gauge type detector.

According to the power self-supporting river monitoring apparatus of the fifth aspect, the river monitoring information can be wirelessly transmitted to the remote place by the transmitter.

According to the power self-supporting river monitoring device of the sixth aspect, the river monitoring information can be grasped visually at the site by the display.

According to the self-supporting river monitoring device of the seventh aspect , even if a malfunction occurs in the power generation device temporarily, the control device can be driven by the power stored in the capacitor.

According to the power self-supporting river monitoring device of the eighth aspect , the monitoring device can be prevented from being damaged by driftwood or the like flowing on the water surface.

According to the self-supporting river monitoring device of the ninth aspect, it can be easily installed even in a river with a shallow water depth.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a front view of a power self-supporting river monitoring apparatus 1 according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA showing a side view thereof. The power self-supporting river monitoring apparatus 1 includes a ring 2 disposed in a fluid, a support 3 that supports the ring 2, and a support 3 that is disposed between the support 3 and the fixed base 4. A drag detector 5 that detects an acting drag, a controller 6 that processes a signal from the drag detector 5, and a power generator 7 that supplies electric power to the controller 6 are provided.

  The ring 2 disposed in the fluid has an annular body made of a metal or plastic material. The cross-sectional shape is circular or polygonal, and the ring 2 is disposed so as to be substantially perpendicular to the fluid flow direction 8. By disposing the ring 2 in this manner, a drag force of the fluid acts on the ring 2 and a Karman vortex is generated due to the flow of the fluid. Support rods 9 constituting a part of the support 3 are connected to two positions on the downstream side of the ring 2, so that the drag due to the fluid acting on the ring 2 can be transmitted as it is to the support wing 10 constituting the support 3. The other end of the support rod 9 is connected to the support wing 10. The support wing 10 receives the drag generated in the ring 2 and transmits the drag to the drag detector 5. However, in order to reduce the drag received by the support wing 10 itself from the fluid, the cross-sectional shape of the support wing 10 is As shown in FIG. 3, it is formed in a streamline shape.

  A drag detector 5 incorporating a strain gauge is disposed between the fixed base 4 and the support 3. Specifically, the strain gauge type detector 5 is fixed to the lower end of the second columnar body 12 fixed to the lower surface of the fixed base 4. Therefore, when a drag force from the fluid acts on the ring 2, the drag force is transmitted to the support 3, and a bending moment acts on the strain gauge type detector 5 which is a drag detector. When a Karman vortex is generated in the ring 2 due to the flow of fluid, the drag detected by the effectiveness detector 5 does not become a constant value but becomes a vibration value. The output from the drag detector 5 is sent to the control device 6 accommodated in the fixed base 4 via a signal line (not shown).

  The fixed base 4 is made of a metal or plastic material and is levitated and moored on the water surface 13. By levitation and mooring the fixed base 4 on the water surface 13, the river monitoring device 1 can be easily installed even in shallow rivers. On the other hand, depending on the installation location, it may be difficult to avoid floating objects such as driftwood. In such an installation environment, the fixed base 4 can be fixed underwater and installed below the surface of the water.

  The fixed base 4 is provided with a power generator 7. The power generation device 7 includes a first columnar body 11 disposed so that the longitudinal direction intersects with the fluid flow direction 8, and the longitudinal direction intersects with a distance from the first columnar body 11. It comprises a second columnar body 12 disposed, and a vibration power generator 7 disposed between the first columnar body 11 and the fixed base 4.

  Here, the vertical vortex excitation, which is the operating principle of the vibration power generator 7, will be briefly described. In the longitudinal vortex excitation, the first columnar body 11 arranged so that the longitudinal direction intersects with the fluid flow direction 8 is separated from the first columnar body 11 and the longitudinal direction intersects. In the apparatus having the second columnar body 12 arranged, the separation distance (s) between the first columnar body 11 and the second columnar body 12 is larger than the diameter (d) of the first columnar body 11. This occurs when a predetermined value is reached.

  FIG. 4 shows a first columnar body 11 arranged so that the longitudinal direction intersects with the fluid flow direction 8, and is arranged so that the longitudinal direction intersects with a distance from the first columnar body 11. FIG. 4 shows a form of a vertical vortex in an apparatus having a second columnar body 12 provided, the form shown in FIG. 4A is called a trailing vortex, and the form shown in FIG. 4B is a necklace vortex. I will call it. The trailing vortex is generated when the distance (s) between the first columnar body 11 and the second columnar body 12 is smaller than the diameter (d) of the first columnar body 11. On the other hand, the necklace vortex is generated when the distance (s) between the first columnar body 11 and the second columnar body 12 is a relatively large value with respect to the diameter (d) of the first columnar body 11. appear. For example, the trailing vortex shown in FIG. 4A is observed in a water flow with s / d = 0.08 and a flow velocity of 12.8 cm / sec. The necklace vortex shown in FIG. 4B is observed in a water flow with s / d = 0.28 and a flow velocity of 12.5 cm / sec. Longitudinal vortices are periodically generated from the vicinity of the intersection between the first columnar body 11 and the second columnar body 12. It is observed that the vertical vortex takes two forms when the separation gap (s) between the first columnar body 11 and the second columnar body 12 is slightly changed. In addition, the excitation force generated by these two types of longitudinal vortices has a large excitation force that is more than three times the excitation force generated by the conventional Karman vortex, and the distance (s) between the two columnar bodies is slightly changed. It was found that the vibration was maintained even in a wide range of flow velocity. These two types of longitudinal vortex excitation, that is, trailing vortex excitation and necklace vortex excitation, show different forms from the conventional Karman vortex excitation.

  Incidentally, the generation of the vertical vortex occurs not only when the fluid is a liquid such as water but also when the fluid is a gas such as air. FIG. 5 shows a first columnar body arranged so that the longitudinal direction intersects with the air flow direction, and a longitudinal direction spaced apart from the first columnar body. It is an experimental result which shows the relationship between the flow velocity of air and the amplitude of a 1st columnar body in the apparatus which has a 2nd columnar body. In the figure, the data of (1) shows the relationship of the amplitude to the vortex in a single columnar body, that is, the flow velocity by normal Karman vortex excitation. The change of the amplitude with respect to the flow velocity is extremely sensitive, and when the flow velocity fluctuates even slightly from the flow velocity corresponding to the resonance frequency, the amplitude decreases rapidly. The data of (2) shows the relationship of the amplitude to the flow velocity due to the trailing vortex excitation at s / d = 0.08. The trailing vortex excitation occurs in a region where the flow velocity is higher than that of the Karman vortex excitation, and the change in amplitude with respect to the flow velocity is insensitive. The data of (3) shows the relationship of the amplitude to the flow velocity due to necklace vortex excitation at s / d = 0.28. Necklace vortex excitation occurs in a region where the flow velocity is higher than that of trailing vortex excitation. And the change of the amplitude with respect to the flow velocity due to the necklace vortex excitation is extremely insensitive, and maintains a large value without the amplitude being attenuated in a wide flow velocity region. In the example of FIG. 5, it can be seen that a large amplitude is maintained in a wide range of flow velocity ranging from 7.5 to 13 m / sec. From these data, it can be seen that if the necklace vortex excitation can be used for wind power generation and hydropower generation, a power generation device applicable to a wide range of wind speeds and water flow velocities can be realized.

  The power self-supporting river monitoring apparatus 1 according to the present invention includes a vibration power generation apparatus 7 that applies the principle of longitudinal vortex excitation as described above. As shown in FIGS. 1 and 2, the first columnar body 11 is disposed so that the longitudinal direction intersects the fluid flow direction 8. The second columnar body 12 is disposed so as to be spaced apart from the first columnar body 11 and in the longitudinal direction. Both ends of the first columnar body 11 are elastically supported by leaf springs 15 provided at the lower end of a fixed shaft 14 whose one end is fixed to the fixed base 4. That is, the first columnar body 11 has high rigidity with respect to the fluid flow direction 8, but has low rigidity with respect to the direction intersecting with the fluid flow direction 8 (vertical direction in the figure), and easily vibrates up and down due to external force. It is supported to do. A rod-shaped permanent magnet 16 is attached to both ends or one end of the first columnar body 11, and when the first columnar body 11 vibrates in the vertical direction in water, the permanent magnet 16 also vibrates in the vertical direction. . A coil 17 made of a conductive material is disposed around the permanent magnet 16, and the coil 17 is attached to the fixed base 4 by a coil mounting body (not shown). The winding end of the coil 17 is connected to the control device 6 so that the electric power generated in the coil 17 is supplied to the control device 6. That is, when a vertical vortex is generated around the first columnar body 11 due to the flow of fluid, the first columnar body 11 vibrates in the vertical direction, and the permanent magnet 16 provided at the end of the first columnar body 11. Moves relative to the coil 17. Then, AC power is generated in the coil 17 by electromagnetic induction, and power can be supplied to the control device 6. Further, the control device 6 is provided with a rectifier, a charger, and a capacitor so that the AC power generated by the vibration power generator 7 can be supplied to the control device 6 as stable DC power. In addition to the electromagnetic induction system using the permanent magnet 16 and the coil 17 as described above, the vibration power generator 7 presses the piezoelectric element and the piezoelectric element between the first columnar body 11 and the fixed base 4. A power generation device made of a pressing body can also be provided.

  Next, a ring vortex flowmeter will be described. The ring vortex flowmeter belongs to the Karman vortex flowmeter, which is a known technique, and generates a Karman vortex by the ring 2 disposed in the fluid and obtains the flow velocity from the frequency change of the Karman vortex. A Karman vortex having a frequency corresponding to the flow velocity is generated in the ring 2 arranged so as to intersect the fluid flow direction 8. That is, the frequency of the Karman vortex street changes according to the flow velocity of the fluid. When the frequency of the Karman vortex street changes, the drag that the ring 2 receives from the fluid also changes. The ring 2 is supported by a support 3 and causes a strain change in a strain gauge 5 which is a drag detector disposed between the support 3 and the fixed base 4. That is, the frequency change due to the Karman vortex street generated in the ring 2 is detected as a resistance change of the strain gauge 5.

  FIG. 6 is a block diagram showing the configuration of the control device 6. The configuration of the control device 6 belongs to a known technique, and the outline will be briefly described. A change in resistance of the strain gauge 5 as a drag detector is amplified by the charge amplifier 21. Note that calibration of the strain gauge 5 and the charge amplifier 21 is performed as an initial setting operation. Only the fundamental frequency is extracted from the output from the charge amplifier 21 by the low-pass filter 22, and the higher-order vibration frequency is cut. This is because the frequency of the Karman vortex street as the flow velocity information is included in the fundamental frequency. The signal after passing through the low-pass filter 22 is input to the CPU 24 which is an arithmetic device via the A / D converter 23. The signal input to the CPU 24 is output to a display 25 consisting of a liquid crystal display or a light emitting diode, and displayed so that a human can directly recognize the flow velocity. Further, a signal input to the CPU 24 as needed is wirelessly transmitted from the antenna via the transmitter 26 and transmitted to a remote river monitoring station or the like. Further, the control device 6 includes a battery 27 for storing the power generated by the vibration power generator 7, a charger necessary for storing the power in the battery 27, and the like.

  According to the power self-supporting river monitoring apparatus 1 according to the above-described embodiment, it is possible to generate power using fluid energy, and therefore it is possible to monitor the river situation even in a place where a commercial power network is not provided. In addition, a compact and inexpensive river monitoring device 1 can be realized, and highly reliable power generation can be performed over a long period of time. Further, the river monitoring information can be wirelessly transmitted to a remote location by the transmitter 26, and the river monitoring information can be grasped visually at the site by the display unit 25. Further, even if a malfunction occurs in the power generation device 7, the control device 6 can be reliably driven by the electric power stored in the battery 27.

  As mentioned above, although this invention was demonstrated based on the Example, this invention can carry out various deformation | transformation implementation. For example, in the above embodiment, the case where the first columnar body 11 is supported at both ends has been described. However, the first columnar body 11 is not limited to being supported at both ends, and cantilevered support is used. You can also. Further, the power generation device 7 may be provided not between both ends of the first columnar body 11 but between one end of the first columnar body 11 and the fixed base 4. Furthermore, in the said Example, only the vibration power generation device 7 by the fluid was used as a power generation device, However, A solar cell panel is attached to the fixed base 4 as needed, and a solar cell and vibration power generation device 7 are used together. It is good.

It is a front view of the electric power self-supporting river monitoring device showing an embodiment of the present invention. It is AA arrow sectional drawing in FIG. It is a BB arrow line view in FIG. The state of a longitudinal vortex is shown, (a) shows a trailing vortex excitation, and (b) shows a necklace vortex excitation. It is a characteristic view which shows the relationship between the flow velocity of a fluid, and the amplitude of a columnar body. It is a block diagram which shows the structure of a control apparatus.

1 Electric power self-supporting river monitoring device (river monitoring device)
2 Ring 3 Support 4 Fixed base 5 Drag detector (strain gauge type detector, strain gauge)
6 Control device 7 Power generation device (vibration power generation device)
11 First columnar body
12 Second columnar body
25 Display
26 Transmitter
27 Battery

Claims (9)

A ring disposed in a fluid; a support for supporting the ring; a drag detector disposed between the support and a fixed base for detecting a drag acting on the ring; and the drag detector A first columnar body that includes a control device that processes a signal from the power generation device and a power generation device that supplies power to the control device, the power generation device being disposed so that a longitudinal direction intersects a fluid flow direction And a second columnar body arranged to be separated from the first columnar body and intersecting in the longitudinal direction, and a vibration disposed between the first columnar body and the fixed base. A power self-supporting river monitoring device comprising: a power generation device. The vibration power generator power freestanding river monitoring device according to claim 1, characterized in that the electromagnetic induction method. The vibration power generator power freestanding river monitoring device according to claim 1, characterized in that the power generating apparatus comprising a pressing member for pressing the piezoelectric element and the piezoelectric element. The power self-supporting river monitoring apparatus according to any one of claims 1 to 3 , wherein the drag detector is a strain gauge type detector. The power self-supporting river monitoring device according to any one of claims 1 to 4 , wherein the control device includes a transmitter that transmits river monitoring information. The said control apparatus is provided with the indicator which displays river monitoring information, The electric power self-supporting river monitoring apparatus of any one of Claims 1-5 characterized by the above-mentioned. The power self-supporting river monitoring device according to any one of claims 1 to 6 , further comprising a capacitor that stores electric power generated by the power generation device. The power self-supporting river monitoring device according to any one of claims 1 to 7 , wherein the fixed base is fixed in water. The power self-supporting river monitoring device according to any one of claims 1 to 7 , wherein the fixed base is levitated and moored on a water surface.