JP2013156175A - Optical type flow velocity/water pressure measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent error in flow velocity measurement and water pressure measurement of flowing water flowing in a flow passage such as a river.SOLUTION: An optical type flow velocity/water pressure measurement device comprises: a first fiber black grating 11 for detecting stress corresponding to flow velocity; a load transmission mechanism 12 for transmitting load of the stress to the first fiber black grating 11; a first housing 15 provided with a first diaphragm 13 for receiving the stress, and forming a first airtight chamber 14 for housing the first fiber black grating 11 and the load transmission mechanism 12; a flow velocity measurement part 2 provided with a pressure plate 16 provided on the upstream side of the first housing 15; a second fiber black grating 31 for detecting water pressure; a water pressure measurement part 3 having a second diaphragm 33 for transmitting the water pressure to the second fiber black grating 31 and a second housing 35 forming a second airtight chamber 34 for housing the second fiber black grating 31. The first airtight chamber 14 and the second airtight chamber 34 are provided adjacent to each other.

Description

  The present invention relates to an apparatus for measuring flow velocity and water pressure using a fiber black grating (FBG), and more specifically to an apparatus for measuring the flow velocity and water pressure of flowing water flowing through a channel such as a river or a pipeline. Is.

  A conventional optical flow velocity measuring device using FGB is disclosed in Patent Document 1, for example. In Patent Document 1, a housing that forms an airtight chamber, an FBG that is accommodated in the housing, is displaced according to stress, and emits light having a wavelength according to the amount of displacement, and an upstream side outside the housing. The pressure receiving plate receives a force corresponding to the flow velocity of the flowing water, and a shaft having one end fixed to the pressure receiving plate. The shaft is displaced according to the force acting on the pressure receiving plate, and the FBG is displaced by the displacement. And a load transmission mechanism. Moreover, in Patent Document 1, in order to enable a highly reliable flow velocity measurement over a long period of time, a load transmission mechanism includes a boss portion that is penetrated by a shaft and fixed to a pressure receiving plate, and an inner peripheral portion that is a boss portion. A diaphragm fixed to the outer periphery and having an outer peripheral portion fixed to the housing side, and O-rings are provided between the pressure receiving plate and the shaft and between the boss portion and the shaft.

  Also, a conventional optical water pressure measuring device using FGB is disclosed in Patent Document 2, for example. Patent Document 2 is an optical water pressure measuring device in which an FBG formed in a part in the length direction of an optical fiber is attached to a diaphragm that converts a change in pressure into a change in strain, and only two points on both sides of the FBG are attached. The FBG is fixed to the diaphragm so that there is no slack.

  In general, when measuring flowing water flowing through a channel such as a river or a pipeline, not only is a flow velocity measuring device installed to measure the water flow velocity, but a water pressure measuring device is also installed to measure the water pressure. In addition to measuring the flow rate, the water level at the point where the flow rate was measured is also measured, thereby measuring the water level at that point. By measuring the water level at the point, the flow velocity according to the water level at the point can be accurately calculated.

  However, conventionally, in order to measure the flow velocity and the water pressure, it is necessary to install the optical flow velocity measuring device exemplified in Patent Document 1 and the optical water pressure measuring device exemplified in Patent Literature 2 at different points. It was. Therefore, the flow velocity measurement point and the water pressure measurement point are separated from each other, so that the flow velocity according to the water level cannot be accurately calculated at the flow velocity measurement point, or the flow rate at the flow velocity measurement point is likely to have an error. was there.

  Moreover, since the flow of water is easily obstructed by installing the flow velocity measuring device and the water pressure measuring device at different points, there is a problem that the flow velocity and the flow rate cannot be accurately calculated.

JP 2009-236777 A JP 2002-98604 A

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a measuring apparatus that can accurately calculate a flow velocity according to a water level and prevent an error in measuring a flow rate. To do.

  An aspect of the present invention is an optical flow velocity / water pressure measuring device that is disposed in a flow channel and measures a flow velocity and a water pressure of flowing water flowing in the flow channel, and detects a stress corresponding to the flow velocity. And a load transmission mechanism that transmits the stress load to the first fiber black grating in conjunction with the stress load, and a first diaphragm that receives the stress, and the first fiber black grating and the load transmission A first housing that forms a first hermetic chamber that houses a mechanism; and a flow velocity measuring unit that is provided upstream of the flowing water outside the first housing and includes a pressure receiving plate that transmits the stress to the first diaphragm. A second fiber black grating for detecting the water pressure and receiving the water pressure and transmitting the water pressure to the second fiber black grating A second diaphragm, and a water pressure measuring unit that includes the second diaphragm and includes a second housing that forms a second hermetic chamber that accommodates the second fiber black grating. The optical flow velocity water pressure measuring device is characterized in that the second hermetic chamber is provided on the downstream side of the flowing water adjacent to the first hermetic chamber.

  In the optical flow rate water pressure measuring device of the above aspect, the first hermetic chamber of the flow rate measuring unit and the second hermetic chamber of the water pressure measuring unit are integrated, not separate. That is, the flow velocity measurement unit and the water pressure measurement unit are integrated. Moreover, the optical flow velocity water pressure measuring apparatus of the said aspect is installed in a flow path so that a flow velocity measurement part may be arrange | positioned in the upstream of flowing water, and a water pressure measurement part may be arrange | positioned in the downstream, respectively.

  According to another aspect of the present invention, there is provided an optical flow velocity water pressure measuring device characterized in that a flowing water regulating member for suppressing the flowing water from affecting the deflection of the second diaphragm is provided at the bottom. .

  In the aspect of the present invention, the flowing water regulating member is a plate-like body, and a groove in a direction parallel to the flowing direction of the flowing water is formed from one end portion of the plate-like body surface to the other end portion. This is an optical flow velocity water pressure measuring device.

  According to an aspect of the present invention, the flowing water regulating member is a plate-like body, and extends from an upstream end of the plate-like body surface. The groove is parallel to the flowing direction of the flowing water, and downstream of the groove. The optical flow velocity water pressure measuring device is characterized in that a groove in the direction of more than 0 ° and less than 90 ° with respect to the flowing direction of the flowing water is formed on the side.

  An aspect of the present invention is the optical flow velocity water pressure measuring device, wherein the load transmission mechanism is provided with a load transmission regulation structure for preventing the first fiber black grating from being damaged.

  An aspect of the present invention is an optical flow velocity water pressure measuring device in which a temperature compensating fiber black grating is accommodated in the first hermetic chamber or the second hermetic chamber. In the present invention, since the first hermetic chamber and the second hermetic chamber are adjacent to each other and integrated, the temperature of the first fiber black grating and the second fiber black grating is determined by one temperature compensating fiber black grating. Correction is possible.

  An aspect of the present invention is an optical flow velocity water pressure measuring device in which a dummy optical fiber or a dummy optical fiber ribbon is provided in parallel to the longitudinal direction of the first fiber black grating. is there. The “dummy optical fiber” means an optical fiber in which a fiber black grating is not formed, and thus does not detect stress according to the flow velocity. The above “dummy optical fiber tape core wire” means a tape core wire having an optical fiber in which a fiber black grating is not formed, and thus a stress corresponding to a flow rate is not detected. The stress transmitted to the first fiber black grating can be adjusted by adjusting the number of dummy optical fibers and dummy optical fiber ribbons.

  According to an aspect of the present invention, an optical flow velocity water pressure measuring device including a flowing water regulating member having a groove formed in a direction parallel to a flowing direction of the flowing water is installed in a flow path of flowing water, and the optical flow velocity water pressure is The flow velocity water pressure measuring method is characterized in that the flow rate and the water pressure of the flowing water are measured by rectifying the flow on the downstream side of the measuring device.

  In the aspect of the present invention, an optical flow velocity water pressure measuring device including a water flow regulating member in which a groove parallel to the flow direction of the flowing water is formed is installed in the sewer, and the foreign matter flowing in the sewer is The flow velocity water pressure measuring method is characterized in that the flow velocity and the water pressure of the flowing water in the sewer are measured while preventing the accumulation around the optical flow velocity water pressure measuring device and washing the periphery.

  According to the above aspect, since the flow velocity measurement unit and the water pressure measurement unit are adjacent to each other and integrated, the size can be reduced, and the flow velocity measurement point and the water pressure measurement point can be substantially matched. As a result, the flow velocity corresponding to the water level can be accurately calculated at the flow velocity measurement point, and an error can be prevented from occurring in the flow rate measurement value at the flow velocity measurement point. Furthermore, since the flow velocity measuring unit and the water pressure measuring unit are integrated, it is possible to suppress the flowing water from being obstructed by the optical flow velocity water pressure measuring device, and as a result, the flow velocity and the flow rate can be accurately calculated.

  According to the above aspect, since the flowing water restricting member suppresses the flowing water from affecting the bending of the second diaphragm, the second diaphragm bends according to the water pressure regardless of the flowing water, and as a result, the water pressure is accurately measured. it can.

  According to the above aspect, since the grooves are provided on the surface of the flowing water regulating member which is a plate-like body in a direction parallel to the flowing direction of the flowing water, sand, mud in the flow path carried by the flowing water, Foreign matters such as dust are smoothly flowed to the downstream side of the optical flow velocity water pressure measuring device by passing through the groove. In this way, the groove exhibits a self-cleaning action that allows foreign matter to flow downstream of the optical flow velocity water pressure measuring device. The self-cleaning action of the groove can prevent foreign matter flowing in the flow path from accumulating on the optical flow velocity water pressure measuring device and its surroundings. It is possible to prevent the displacement of the plate from being obstructed and to measure the flow velocity more accurately. Moreover, since it can prevent that the foreign material deposited around the optical type flow velocity water pressure measuring device influences the bending of a 2nd diaphragm, a water pressure can be measured more correctly. Furthermore, since the Karman vortex can be prevented from being generated on the downstream side of the optical flow velocity water pressure measuring device by the groove, the flow around the optical flow velocity water pressure measuring device can be rectified.

  According to the above aspect, in addition to the grooves in the direction parallel to the flowing direction of the flowing water, the grooves in the direction of more than 0 ° and less than 90 ° with respect to the flowing direction of the flowing water are formed. It is possible to more reliably prevent foreign matter from accumulating on the optical flow velocity water pressure measuring device and its peripheral part.

  According to the above aspect, since the load transmission restricting structure that prevents the first fiber black grating from being damaged is provided, even if the flow velocity becomes unexpectedly high and the stress transmitted to the first fiber black grating increases. Failure of the optical flow rate water pressure measuring device can be prevented.

  According to the above aspect, since the temperature correction of the first fiber black grating and the second fiber black grating is performed with one temperature compensating fiber black grating, the structure of the apparatus can be simplified and the manufacturing cost can be reduced.

  According to the above aspect, since the stress transmitted to the first fiber black grating by the dummy optical fiber or the dummy optical fiber ribbon can be adjusted, the sensitivity of the flow velocity measuring unit can be adjusted according to the flow velocity at the measurement point.

It is a front view which shows the inside of the optical flow velocity water pressure measuring apparatus which concerns on the example of embodiment of this invention. It is side surface sectional drawing of the optical type flow velocity water pressure measuring apparatus which concerns on the example of embodiment of this invention. It is a front view of the load transmission regulation structure concerning the example of an embodiment of the present invention. It is a schematic diagram which shows the optical path | route in which FBG in an optical flow velocity water pressure measuring device, an external light source, etc. were connected by the optical fiber. It is a front view of the flowing water regulation member concerning an example of an embodiment. It is a front view of the flowing water control member which concerns on the example of 2nd Embodiment. It is a front view of the flowing water control member which concerns on the example of 3rd Embodiment.

  Hereinafter, an optical flow velocity water pressure measuring apparatus according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, an optical flow velocity water pressure measuring apparatus 1 according to an embodiment of the present invention includes a flow velocity measuring unit 2 and a water pressure measurement adjacent to the flow velocity measuring unit 2 on the downstream side of the flow velocity measuring unit 2. The flow rate measuring unit 2 and the water pressure measuring unit 3 are connected to each other via the connecting unit 4 so that the flow rate measuring unit 2 and the water pressure measuring unit 3 are integrated. The strength of the connecting portion 4 is reinforced by a plate-like connecting portion reinforcing member 43 provided around the connecting portion 4. Further, one sheet-like flowing water regulating member 5 is installed from the bottom 30 of the flow velocity measuring unit 2 to the bottom 32 of the water pressure measuring unit 3.

  The flow velocity measuring unit 2 may have a structure similar to that of a conventional optical flow velocity measuring device using a fiber black grating, and therefore, the flow velocity can be measured by the same mechanism as in the past.

  As shown in FIGS. 1 and 2, the flow velocity measuring unit 2 according to the embodiment is coupled to the first fiber black grating (first FBG) 11 that detects stress according to the flow velocity, and the stress load, The first FBG 11 includes a load transmission mechanism 12 that transmits the stress load, and a first diaphragm 13 that receives the stress, and forms a first hermetic chamber 14 that houses the first FBG 11 and the load transmission mechanism 12. A housing 15 is provided.

  The load transmission mechanism 12 is provided on the upstream side of the first housing 15, and a single shaft 17 having one end fixed to an upstream pressure receiving plate 16 that receives a force according to the flow velocity of the flowing water F, Fixed to the shaft 17 but not fixed to the first housing 15. The first FBG downstream mounting base 18, which is a movable block, is fixed to the first housing 15 but not fixed to the shaft 17. And a first FBG upstream mounting base 19 which is a fixed block. When the upstream pressure receiving plate 16 receives a force corresponding to the flow velocity of the flowing water F, the shaft 17 having one end fixed to the upstream pressure receiving plate 16 is displaced downstream, and this displacement amount Accordingly, the first FBG downstream mounting base 18 is also displaced downstream. At this time, even if the shaft 17 is displaced downstream, the first FBG upstream mounting base 19 is not displaced because it is fixed to the first housing 15. Due to the displacement of the first FBG downstream mount 18, the first FBG 11 in which one end portion is attached to the first FBG upstream mount 19 and the other end is attached to the first FBG downstream mount 18 with an adhesive, As a result, the first FBG 11 is displaced under stress in the elongation direction.

  Moreover, you may attach the load transmission control structure 20 to the load transmission mechanism 12 as needed. 2 and 3, the load transmission restricting structure 20 is fixed to the first housing 15 adjacent to the upstream side of the first FBG downstream mounting base 18 but is fixed to the shaft 17. Fixed to the first housing 15 adjacent to the downstream side of the first FBG downstream mounting base 18 but not fixed to the shaft 17, the fixed And a downstream load transmission restricting base 22 which is a block. That is, the upstream load transmission restriction base 21 and the downstream load transmission restriction base 22 are arranged on a straight line along the flow direction of the flowing water F, and the first FBG downstream mounting base 18 is connected to the upstream load transmission restriction base 21. It is arranged between the downstream side load transmission regulation base 22. Therefore, the downstream surface 23 of the upstream load transmission restriction base 21 and the upstream surface 24 of the first FBG downstream mounting base 18 face each other at a predetermined interval, and the upstream surface 25 of the downstream load transmission restriction base 22 The downstream surface 26 of the first FBG downstream mount 18 is opposed at a predetermined distance.

  When the upstream pressure receiving plate 16 receives a force corresponding to the speed of the flowing water F and the first FBG downstream mounting base 18 is displaced downstream according to the stress, the upstream pressure receiving plate 16 is caused by the extension of the first FBG 11. Even when an excessive force leading to breakage is received, the first FBG downstream mounting base 18 comes into contact with the downstream load transmission regulating base 22 of the load transmission regulating structure 20 from the upstream side, so that the first FBG downstream mounting base 18 is predetermined. The displacement to the downstream side exceeding the amount of displacement is regulated. In this way, the displacement amount of the first FBG downstream mounting base 18 is restricted, thereby preventing damage due to the extension of the first FBG 11. Depending on the type of optical fiber forming the FBG, the FBG may not break until the elongation reaches several percent, but the FBG usually breaks when the elongation reaches about 2%. Further, when the elongation is repeatedly applied to the FBG, the fracture may occur even when the elongation is about 2% or less. For this reason, it is desirable to regulate the elongation of the FBG within a range of an elongation that does not cause breakage even if the FBG is repeatedly elongated, that is, an allowable elongation. Therefore, in the embodiment of FIG. 3, the allowable elongation is set to 0.2%. Therefore, the maximum elongation of the first FBG 11 is 0.2% (in the embodiment shown in FIG. 3, the length of the first FBG 11 between the first FBG downstream mounting base 18 and the first FBG upstream mounting base 19 is 25 mm. , The elongation corresponding to 0.2% elongation is 50 μm), that is, the first FBG downstream mounting base 18 where the displacement amount of the first FBG 11 is at the zero point, upstream of the downstream load transmission regulating base 22. The downstream load transmission restriction base 22 is attached at a position where the distance between the side surface 25 and the downstream side surface 26 of the first FBG downstream attachment base 18 is 50 μm.

  Since the load transmission restriction structure 20 can be regulated with higher precision than a structure that directly regulates deformation of the first diaphragm 13, it is possible to reliably prevent the first FBG 11 from being damaged.

  When the optical flow velocity / water pressure measuring device 1 needs to be installed at an inclined point where the upstream side is inclined downward with respect to the downstream side, the upstream FBG downstream mounting base 18 is predetermined. This is to prevent the first FBG 11 from being damaged by restricting the displacement to the upstream side beyond the displacement amount of the first FBG 11. Normally, the FBG breaks when a curved shape with a small bending radius is formed by the deflection. Therefore, the distance between the downstream surface 23 of the upstream load transmission regulation base 21 and the upstream surface 24 of the first FBG downstream mounting base 18 is such that no breakage occurs due to bending of the optical fiber, for example, less than 100 μm (FIG. 3 The upstream load transmission regulation base 21 is attached so as to be 50 μm.

  As described above, the first FBG 11 is attached to the first FBG upstream mounting base 19 at one end and to the first FBG downstream mounting base 18 at the other end. Further, as shown in FIG. 1, in the parallel direction to the longitudinal direction of the first FBG 11, that is, in the parallel direction, the vicinity of one end is the first FBG upstream mounting base 19, and the other end is the first FBG downstream mounting base 18. The dummy optical fiber 27 or the dummy optical fiber ribbon 27 'attached to the substrate may be attached with an adhesive. In this embodiment, a dummy optical fiber ribbon 27 'is used.

  The number of dummy optical fibers 27 or dummy optical fiber ribbons 27 ′ can be appropriately selected according to the sensitivity required for the flow velocity measuring unit 2 described later. In FIG. 3, one dummy optical fiber tape core wire 27 ′ is attached on each of the left and right sides around the first FBG 11. By attaching the dummy optical fiber 27 or the dummy optical fiber ribbon 27 'as described above, the stress applied to the first FBG 11 is reduced according to the number of the optical fibers. By reducing the stress applied to the first FBG 11, the displacement amount of the first FBG 11 is reduced, and as a result, the sensitivity of the flow velocity measuring unit 2 can be adjusted. Further, by using the optical fiber or the optical fiber ribbon for the dummy, it is possible to easily balance the tension of the first FBG 11 as compared with the case of using another member such as a metal foil.

  A first diaphragm 13 made of metal is provided on the upstream side of the shaft 17, and the first diaphragm 13 is bent according to the displacement of the shaft 17. A downstream diaphragm 28 made of metal is provided on the downstream side of the shaft 17. The first housing 15 having the first diaphragm 13 and the downstream diaphragm 28 forms a first hermetic chamber 14 that is kept highly airtight.

  Further, as shown in FIG. 2, the downstream diaphragm 28 is formed on the plate-like connecting portion reinforcing member 43 on the side surface portion of the light flow velocity water pressure measuring device 1 with respect to the outside of the light flow velocity water pressure measuring device 1. The hole 44 is in an open state. Since the downstream diaphragm 28 can smoothly contact the running water F in the flow path through the hole 44, the downstream diaphragm 28 can receive the water pressure (static pressure) of the running water F. Therefore, the water pressure (static pressure) acting on the upstream pressure receiving plate 16 can be canceled by the downstream diaphragm 28. The static pressure acting on the upstream pressure receiving plate 16 that receives a force according to the flow velocity of the flowing water F is canceled by the downstream diaphragm 28, so that when the flow velocity of the flowing water F is zero, the displacement amount of the first FBG 11 becomes zero. It can be maintained.

  The water pressure measurement unit 3 is a part that measures the static pressure of water, and may have the same structure as a conventional optical water pressure measurement device using a fiber black grating. Therefore, the water pressure can be measured by the same mechanism as in the past.

  As shown in FIGS. 1 and 2, the water pressure measurement unit 3 according to the embodiment receives a second fiber black grating (second FBG) 31 that detects water pressure and the water pressure, and transmits the water pressure to the second FBG 31. A second diaphragm 33 made of metal and a second housing 35 that includes the second diaphragm 33 and forms a second hermetic chamber 34 that houses the second FBG 31 are provided.

  As shown in FIG. 2, the second diaphragm 33 is disposed at a position higher than the bottom of the second housing 35. Moreover, the 2nd diaphragm 33 is made into the open state by the through-hole 60 formed in the flowing water control member 5 of the plate-shaped body mentioned later with respect to the outside of the optical flow velocity water pressure measuring apparatus 1. FIG. Therefore, since the 2nd diaphragm 33 can contact smoothly the flowing water F in a flow path, it has the structure which can measure a water pressure correctly. Two second FBG mounting bases 38 and 39 are arranged opposite to each other on the second airtight chamber side 34 of the second diaphragm 33, and one end portion of the second FBG 31 is attached to one second FBG mounting base 38. The vicinity of the other end of the 2FBG 31 is attached to the other second FBG mount 39.

  The second housing 35 including the second diaphragm 33 forms a second hermetic chamber 34 that is kept highly airtight. When water pressure is applied to the second diaphragm 33, the second diaphragm 33 bends, and the two second FBG mounts 38, 39 are displaced in response to the bend, and the second FBG 31 is distorted.

  A temperature compensation fiber black grating (temperature compensation FBG) 36 for detecting the temperature and compensating the temperature is separately provided in the second hermetic chamber 34 of the water pressure measurement unit 3. Further, in order to accurately measure the water pressure, the inside of the second hermetic chamber 34 of the water pressure measuring unit 3 is preferably adjusted to the atmospheric pressure. Therefore, in addition to the optical flow velocity water pressure measuring device 1, a pressure measuring device is separately provided. (Not shown) is installed. Since the atmospheric pressure introduction pipe of the pressure measuring device and the inside of the second hermetic chamber 34 are connected, the inside of the second hermetic chamber 34 is corrected to the atmospheric pressure.

  As shown in FIG. 4, a light source 51, a wavelength meter 52, a data processing device 53, and an optical circulator 54 are additionally provided outside the optical flow velocity water pressure measuring device 1. The optical circulator 54 and the second FBG 31 are connected by an optical fiber 55, and the second FBG 31 and the first FBG 11 are connected by an optical fiber 56. The other end of the optical fiber 57 connected to the first FBG 11 at one end is a non-reflective end 58. The optical fiber 55 connecting the optical circulator 54 and the second FBG 31 is separately provided with a temperature compensating FBG 36 at a position corresponding to the second hermetic chamber 34. Optical fibers 59 and 59 'are connected between the optical circulator 54 and the light source 51, and between the optical circulator 54 and the wavelength meter 52, respectively.

  Light from the light source 51 passes through the optical circulator 54 in the order of the optical fiber 55 provided with the temperature compensating FBG 36, the second FBG 31, the optical fiber 56, the first FBG 11, and the optical fiber 57. When the upstream pressure receiving plate 16 receives a force corresponding to the speed of the flowing water F, the first FBG 11 is displaced according to the stress and an elongation strain is generated. As a result, the period of the diffraction grating of the first FBG 11 changes to shift the Bragg wavelength (a specific wavelength region reflected by the FBG), and light having a wavelength corresponding to the amount of displacement of the shaft 17, that is, the amount of elongation strain of the first FBG 11. Is emitted as reflected light from the first FBG 11. The emitted light passes through the optical fiber 56 and the optical fiber 55 in this order, and is sent to the wavelength meter 52 via the optical circulator 54. Further, the wavelength data observed by the wavelength meter 52 is sent to the data processing device 53. The data processing device 53 obtains the flow velocity based on the data sent from the wavelength meter 52.

  When the second diaphragm 33 bends according to the water pressure, the two second FBG mounts 38 and 39 attached to the second airtight chamber 34 side of the second diaphragm 33 are displaced according to the amount of the bend, respectively. A predetermined amount of distortion occurs in the second FBG 31 in accordance with the amount of displacement of the 2FBG mounts 38 and 39. As a result, the period of the diffraction grating of the second FBG 31 changes and the Bragg wavelength shifts, and light having a wavelength corresponding to the distortion amount of the second FBG 31 is emitted from the second FBG 31 as reflected light. The emitted light is sent to the wavelength meter 52 via the optical fiber 55 and the optical circulator 54. Further, the wavelength data observed by the wavelength meter 52 is sent to the data processing device 53. The data processing device 53 obtains the water pressure based on the data sent from the wavelength meter 52.

  The wavelength meter 52 can identify which FBG is reflected by setting the black wavelengths of the first FBG 11, the second FBG 31, and the temperature compensating FBG 36 to different wavelengths.

  In the optical flow velocity hydraulic pressure measuring device 1 according to the embodiment of FIGS. 1 and 2, the connecting portion 4 is a tubular body, and the upstream end 41 of the connecting portion 4 is fixed to the downstream surface of the first housing 15, The downstream end 42 of the connecting portion 4 is fixed to the upstream surface of the second housing 35. In this way, the tubular connecting portion 4 integrates the flow velocity measuring portion 2 and the water pressure measuring portion 3. In addition, an optical fiber 56 that connects the second FBG 31 and the first FBG 11 and an optical fiber 57 that is connected to the first FBG 11 at one end are inserted into the connecting portion 4.

  Accordingly, the optical fiber 56 and the optical fiber 57 are moved from the inside of the first hermetic chamber 14 to the inside of the connecting portion 4 at a portion of the downstream surface of the first housing 15 where the upstream end 41 of the connecting portion 4 is fixed. Holes corresponding to the diameters of the optical fiber 56 and the optical fiber 57 are formed so that the inside of the first hermetic chamber 14 can maintain hermeticity while being inserted. Similarly, the optical fiber 56 and the optical fiber 57 are connected from the inside of the second hermetic chamber 34 to the inside of the connecting portion 4 at a location where the downstream end 42 of the connecting portion 4 is fixed on the upstream surface of the second housing 34. Holes corresponding to the diameters of the optical fiber 56 and the optical fiber 57 are formed so that the inside of the second hermetic chamber 34 can be kept airtight while being inserted into the optical fiber 56.

  It should be noted that, instead of the above embodiment, the location where the upstream end 41 of the connecting portion 4 is fixed on the downstream surface of the first housing 15 and the connecting portion 4 on the upstream surface of the second housing 35. Are provided with holes having diameters larger than the diameters of the optical fiber 56 and the optical fiber 57, respectively, so that the inside of the first hermetic chamber 14 and the inside of the second hermetic chamber 34 are provided. It is good also as a structure connected via the connection part 4. FIG.

  Moreover, you may provide a flowing water control member in the optical flow velocity water pressure measuring apparatus 1 according to the embodiment. By providing the flowing water restricting member, it is possible to suppress the flowing water F from affecting the bending of the second diaphragm 33 and to measure the water pressure more accurately. The flowing water regulating member is not particularly limited as long as it can suppress the momentum of the flowing water F from the upstream from affecting the bending of the second diaphragm 33. For example, a plate-like body having a predetermined thickness can be mentioned. . By attaching one surface of the plate-like body to the surface of the bottom 30 of the first housing 15 on the side opposite to the first hermetic chamber 14, the flowing water from the upstream side is not hindered. F is regulated by the upstream side surface of the plate-like body, and as a result, it is possible to suppress the flowing water F from the upstream from affecting the bending of the second diaphragm 33.

  In addition, as an example of the flowing water regulating member, as shown in FIGS. 2 and 5, a rectangular plate-like body having dimensions substantially the same as the length and width of the optical flow velocity water pressure measuring device 1 is penetrated in the thickness direction. There is a flowing water regulating member 5 provided with a hole 60 and a notch 61 communicating with the through hole 60. The through hole 60 is provided at a position corresponding to the position of the second diaphragm 33, and the opening 62 of the notch 61 is provided on the downstream side. When this flowing water regulating member 5 is attached to the bottom of the optical flow velocity water pressure measuring device 1, the opening 62 of the notch 61 is provided on the downstream side, so that not only the flowing water F from the upstream can be restricted, but also the optical flow velocity. The running water F from the lateral direction of the water pressure measuring device 1 and the vortex of the running water F generated by the optical flow velocity water pressure measuring device 1 can also be regulated.

  Further, since the through hole 60 is provided at a position corresponding to the position of the second diaphragm 33, the second diaphragm 33 is not disturbed by the flowing water regulating member 5, and the water outside the optical flow velocity water pressure measuring device 1 is not disturbed. The pressure can be accurately received. Since the flowing water regulating member 5 can regulate not only the flowing water F from the upstream but also the flowing water F and the vortex of the flowing water F from the side surface, the flowing water F can be more reliably suppressed from affecting the bending of the second diaphragm 33, Furthermore, the water pressure can be measured with high accuracy. The flowing water regulating member 5 is provided with a screw hole 63 for attaching to the bottom of the optical flow velocity water pressure measuring device 1.

  Moreover, as shown in FIG. 6, as a second embodiment, on the surface of the plate-like body provided with the above-described through hole 60 and the notch 61, and further in a direction substantially parallel to the flow direction of the flowing water F. It is good also as flowing water control member 5 'provided with two or more the longitudinal grooves 64 which are linear grooves. In FIG. 6, the longitudinal grooves 64 are provided in parallel to the longitudinal direction of the flowing water regulating member 5 ′ that is rectangular so as to be parallel to the flowing direction of the flowing water F. The longitudinal groove 64 is formed from one side surface orthogonal to the longitudinal direction of the flowing water regulating member 5 ′ to the other side surface.

  Therefore, when the flowing water regulating member 5 ′ is attached to the bottom of the optical flow velocity water pressure measuring device 1 so that the opening of the vertical groove 64 faces the bottom surface side of the flow path, the sand in the flow path carried by the flowing water F Since foreign matter such as mud and dust enters the longitudinal groove 64 from the upstream side, flows in the longitudinal direction in the longitudinal groove 64, and is discharged to the downstream side of the flowing water regulating member 5 ', the foreign matter is an optical flow velocity water pressure measuring device. 1 is smoothly flowed to the downstream side. In this way, the flowing water regulating member 5 ′ having the vertical groove 64 flows foreign matter downstream of the optical flow velocity water pressure measuring device 1 and prevents foreign matter from accumulating around the optical flow velocity water pressure measuring device 1. Since it has a self-cleaning function, foreign matter can be prevented from affecting the operation of the upstream pressure receiving plate 16 and the deflection of the second diaphragm 33, and the flow velocity and water pressure can be measured with high accuracy.

  On the other hand, when the optical flow velocity water pressure measuring device 1 of the present embodiment is installed in the flowing water F, the flowing water F is disturbed by the optical flow velocity water pressure measuring device 1 and a Karman vortex is generated on the downstream side of the device 1. There is. In particular, when the flow velocity difference between the water surface side portion and the flow path bottom portion side portion of the optical flow velocity water pressure measuring device 1 is large, the Karman vortex tends to occur. However, as described above, when the flowing water regulating member 5 ′ having the vertical groove 64 is attached to the bottom of the optical flow velocity water pressure measuring device 1, the flowing water F passes through the vertical groove 64, thereby suppressing the generation of Karman vortex. The flow around the optical flow velocity water pressure measuring device 1 can be rectified.

  In addition, although the number of the longitudinal grooves 64 may be one or more, a plurality of longitudinal grooves 64 are preferable in terms of enhancing the self-cleaning action and the rectifying action of the flowing water regulating member 5 ′.

  Further, as shown in FIG. 7, as a third embodiment, the flow direction of the flowing water F is further provided on the surface of the rectangular plate-like body provided with the above-described through hole 60, the notch 61, and the vertical groove 64. The flowing water regulating member 5 provided with a plurality of oblique grooves 65 that are linearly formed in a direction exceeding 0 ° and less than 90 ° with respect to the vertical groove 64, ie, in a direction exceeding 0 ° and less than 90 ° with respect to the longitudinal groove 64 The slanted groove 65 communicates with the longitudinal groove 64 and is formed from the connecting portion with the longitudinal groove 64 to the side surface parallel to the longitudinal direction of the flowing water regulating member 5 ″. Further, the oblique groove 65 is provided on the upstream side of the through hole 60. Accordingly, foreign matters such as sand, mud, and dust in the flow channel carried by the running water F enter the vertical groove 64 from the upstream side and flow in the vertical groove 64 in the downstream direction. From the connecting portion into the slanting groove 65 and discharged obliquely downstream of the flowing water regulating member 5 ″. Therefore, it is possible to more reliably prevent foreign matter from being deposited on the optical flow velocity water pressure measuring device 1 and its peripheral portion. In addition, since the oblique groove 65 is provided on the upstream side of the through hole 60, the foreign matter is prevented from flowing into the through hole 60, and the foreign matter in the running water F affects the bending of the second diaphragm 33. Therefore, the accuracy of the water pressure measurement is further improved.

  In FIG. 7, on the downstream side of the through hole 60 in the direction of more than 90 ° and less than 180 ° with respect to the flowing direction of the flowing water F, that is, with respect to the oblique groove 65 on the upstream side of the through hole 60. A plurality of other oblique grooves 66 are formed so as to face each other. The other oblique groove 66 communicates with another vertical groove 67 separately formed on the downstream side of the through hole 60. By means of the oblique grooves 66 and the longitudinal grooves 67 provided on the downstream side of the through-hole 60, foreign matter discharged from the upstream oblique groove 64 in the obliquely downstream direction and foreign matter deposited downstream of the optical flow velocity water pressure measuring device 1 are removed. , Can flow smoothly to the downstream side.

  In addition, although the number of the slanting grooves 64 may be one or plural, a plurality is preferable in terms of enhancing the self-cleaning action of the flowing water regulating member.

  The method for attaching the flowing water regulating member 5, 5 ′, 5 ″ to the optical flow velocity water pressure measuring device 1 is not particularly limited, and examples thereof include screwing using a screw hole 63. Further, the flowing water regulating member. The material of 5, 5 ′, 5 ″ is not particularly limited, but SUS is preferable from the viewpoint of rust prevention and corrosion resistance.

  Next, an example of how to use the optical flow velocity water pressure measuring apparatus 1 according to the embodiment of the present invention will be described. Although the flow path in which the optical flow velocity water pressure measuring apparatus 1 of the present invention is installed is not particularly limited, here, a case where it is installed in a sewer will be described as an example. The optical flow velocity water pressure of the present invention so that the upstream pressure receiving plate 16 of the flow velocity measuring unit 2 faces the upstream side, that is, the water pressure measuring unit 3 is downstream, at a predetermined measurement point on the bottom surface of the sewer. A measuring device 1 is arranged. The optical flow velocity water pressure measurement device is fixed to the bottom of the measurement point by screwing or the like, and the light source, wavelength meter, and data processing device are installed in the observation room on the ground. Thereby, the worker can observe the flow velocity at the measurement point and the water pressure, that is, the water level in the observation room.

  Next, another embodiment will be described. In the above embodiment, the opening 62 of the notch 61 of the flowing water regulating member 5, 5 ′, 5 ″ is downstream, that is, a side surface orthogonal to the longitudinal direction of the flowing water regulating member 5, 5 ′, 5 ″. However, the position of the opening 62 is not particularly limited as long as it is other than the upstream side. For example, the direction orthogonal to the flow direction of the flowing water F, that is, the flowing water regulating members 5 and 5 is provided. It may be provided on one of the side surfaces parallel to the longitudinal direction of “5 ″. In the above embodiment, the temperature-compensating fiber black grating 36 is accommodated in the second hermetic chamber 34. Instead, it may be accommodated in the first hermetic chamber 14.

  In the above embodiment example, in order to allow the foreign matter to flow more smoothly to the downstream side, another diagonal groove 66 and a vertical groove 67 are separately provided on the downstream side of the through hole 60. The vertical groove 67 may not be provided.

  The optical flow velocity water pressure measuring device of the present invention can make the flow velocity measurement point and the water pressure measurement point substantially coincide with each other, and further prevent the occurrence of measurement errors due to foreign matters by attaching a flowing water regulating member provided with a groove. Therefore, it is particularly useful in fields where there are many foreign substances in running water and accurate flow rate and flow rate data is required, such as sewerage.

DESCRIPTION OF SYMBOLS 1 Optical flow measuring device 2 Flow velocity measuring part 3 Water pressure measuring part 5, 5 ', 5 "Flow regulating member 11 1st fiber black grating 12 Load transmission mechanism 14 First airtight chamber 20 Load transmission regulating structure 27 Dummy optical fiber 27 ′ Dummy optical fiber ribbon 31 second fiber black grating 34 second hermetic chamber 36 temperature compensation fiber black grating 64 longitudinal groove 65 oblique groove

Claims (9)

An optical flow rate water pressure measuring device that is disposed in a flow path and measures a flow speed and a water pressure of flowing water flowing in the flow path,
A first fiber black grating that detects stress according to the flow velocity;
A load transmission mechanism for transmitting the stress load to the first fiber black grating in conjunction with the stress load;
A first housing comprising a first diaphragm for receiving the stress, and forming a first hermetic chamber for accommodating the first fiber black grating and the load transmission mechanism;
A flow velocity measuring unit provided on the upstream side of the flowing water outside the first housing and provided with a pressure receiving plate for transmitting the stress to the first diaphragm;
A second fiber black grating for detecting the water pressure;
A second diaphragm that receives the water pressure and transmits the water pressure to the second fiber black grating;
A water pressure measurement unit including a second housing that includes the second diaphragm and forms a second hermetic chamber that houses the second fiber black grating;
The optical flow rate water pressure measuring apparatus, wherein the second hermetic chamber is provided adjacent to the first hermetic chamber on the downstream side of the flowing water in the first hermetic chamber.   2. The optical flow velocity water pressure measuring device according to claim 1, further comprising: a flowing water regulating member for suppressing the flow of the flowing water from affecting the deflection of the second diaphragm. .   The flowing water regulating member is a plate-like body, and a groove in a direction parallel to the flowing direction of flowing water is formed from one end portion of the plate-like body surface to the other end portion. The optical flow velocity water pressure measuring device according to claim 2.   The flowing water regulating member is a plate-like body, and extends from the upstream end of the surface of the plate-like body. The groove is parallel to the flowing direction of the flowing water, and communicates with the groove on the downstream side of the groove. The optical flow velocity water pressure measuring device according to claim 2, wherein a groove having a direction of more than 0 ° and less than 90 ° with respect to a flowing direction of the flowing water is formed.   5. The optical flow velocity water pressure according to claim 1, wherein the load transmission mechanism is provided with a load transmission regulation structure for preventing the first fiber black grating from being damaged. measuring device.   The optical flow velocity water pressure measuring device according to any one of claims 1 to 5, wherein a temperature compensating fiber black grating is accommodated in the first hermetic chamber or the second hermetic chamber.   The dummy optical fiber or the dummy optical fiber tape core wire is provided in parallel with the longitudinal direction of the first fiber black grating, according to any one of claims 1 to 6. Optical flow velocity water pressure measuring device.   The optical flow velocity water pressure measuring device according to claim 3 or 4 is installed in a flow path through which flowing water flows, and a flow on the downstream side of the optical flow velocity water pressure measuring device is rectified to measure the flow velocity and water pressure of the flowing water. The flow velocity water pressure measuring method characterized by this.   5. The optical flow velocity water pressure measuring device according to claim 3 or 4 is installed in a sewer, and foreign matter flowing in the sewer is prevented from accumulating around the optical flow velocity water pressure measuring device to clean the periphery. While measuring the flow velocity and the water pressure of the flowing water in the sewer, the flow velocity water pressure measuring method characterized by the above-mentioned.

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