JP2017150996A - Sensor for detecting state change of solid and method for detecting state change of solid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new sensor having had a wire mesh sensor adopted for detecting a state change of a solid and a method for detecting a state change of a solid.SOLUTION: A sensor for detecting a state change of a solid 11 comprises: a wire mesh sensor 20 having an excitation electrode 22 disposed in the solid 11 and consisting of first wire electrodes 21a-21d disposed with a space from each other and a measurement electrode 24 consisting of second wire electrodes 23a-23d disposed with a space from each other and provided intersecting the first wire electrodes 21a-21d; input means 30 for inputting an excitation signal PI to the first wire electrodes 21a-21d; detection means 40 for detecting measurement signals PO1-PO4 outputted from the second wire electrodes 23a-23d and reflecting capacitance, inductance, or conductance; and arithmetic processing means 50 for arithmetically processing the measurement signals PO1-PO4 reflecting capacitance, inductance, or conductance and detecting a state change of the sold 11.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a solid state change detection sensor and a solid state change detection method.

  As a sensor for obtaining time-series information of the abundance of liquid and gas in a gas-liquid two-phase flow at multiple points in the cross section of the fluid flowing through the pipeline, a wire mesh sensor (Wire- Mesh Sensor (WMS) is known. The wire mesh sensor includes a first wire electrode and a second wire electrode that intersect with each other at a predetermined distance in the axial direction of the pipe through which the fluid flows, and are arranged in a square lattice pattern in the cross section of the pipe. And an impedance measurement sensor using the first wire electrode as an excitation electrode and the second wire electrode as a measurement electrode. In the wire mesh sensor, the wires are close to each other but are not in contact with each other. Hereinafter, a portion where the wires are close to each other is referred to as an intersection for convenience.

  In the impedance measurement sensor having the wire mesh sensor, excitation pulses are sequentially applied from the first row to the input line formed by the first wire electrode by each switch. Here, the excitation pulse is supplied from the power source via the changeover switch. As the excitation pulse is applied, the impedance at each intersection of the first wire electrode and the second wire electrode changes according to the state of the fluid that short-circuits each intersection. As a result, in the impedance measurement sensor, a measurement signal reflecting the impedance at each intersection is output for each row on the output line formed by the second wire electrode. Then, by processing the output measurement signal by the arithmetic processing unit, the abundance of a desired substance such as a gas-liquid ratio in a gas-liquid two-phase flow at each intersection can be measured by calculation.

  Incidentally, in recent years, measurement sensors and measurement systems to which the wire mesh sensor is applied have been developed. Examples of such applications include a lattice sensor (see Patent Document 1) that measures a conductivity distribution in a flow medium for the purpose of measuring a void ratio of a gas-liquid two-phase flow, and a plurality of rod-shaped members. And an impedance measurement sensor (see Patent Documents 2 and 3) that measures a surrounding medium (for example, fluid) or a tertiary that measures a three-dimensional velocity based on the impedance of the measurement object (for example, a bubble) in the flow path An original speed measurement system (see Patent Documents 4 and 5) and the like can be mentioned.

Japanese Patent No. 4090077 Japanese Patent No. 5728764 Japanese Patent No. 5656219 JP 2013-3052 A JP 2013-246124 A

H. Pietrusk. H. -M. Placer / Flow Measurement and Instrumentation 18 (2007) 87-94.

  However, in recent years, further application of the above-described wire mesh sensor is expected.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a novel solid state change detection sensor and a solid state change detection method to which a wire mesh sensor is applied.

  To achieve the above object, a solid state change detection sensor according to a first aspect of the present invention comprises a plurality of first wire electrodes disposed in a solid and spaced apart from each other. A wire mesh sensor comprising: an excitation electrode comprising: a measurement electrode comprising a plurality of second wire electrodes disposed at intervals and intersecting with the plurality of first wire electrodes; Input means for inputting an excitation signal to the first wire electrode, detection means for detecting a measurement signal reflecting the capacitance, inductance or conductance output from the second wire electrode, and reflecting the capacitance, inductance or conductance And an arithmetic processing means for detecting a change in the state of the solid by arithmetic processing of the measured signal.

  In the first aspect of the present invention, it is possible to provide a solid state change detection sensor based on a novel idea that a wire mesh sensor is disposed in a solid. That is, it is possible to provide a solid state change detection sensor capable of easily observing a solid state change over time and non-destructively.

  Further, in the solid state change detection sensor according to the second aspect of the present invention, the wire mesh sensor is disposed in the solid that does not flow, and the arithmetic processing means generates a fluid in the solid. It is characterized by detecting a collision or a mixed state change.

  In the second aspect of the present invention, it is possible to provide a solid state change detection sensor based on the novel idea that the wire mesh sensor is disposed in a solid that does not flow. That is, the state change of the solid can be observed easily and nondestructively over time, and the two-dimensional observation distribution can be appropriately changed according to the form of the solid, so that observation with a higher degree of freedom is performed. It is possible to provide a solid state change detection sensor capable of performing the above.

  In order to achieve the above object, a solid state change detection method according to a third aspect of the present invention includes an excitation electrode composed of a plurality of first wire electrodes spaced apart from each other, and an interval between them. A wire mesh sensor having a measurement electrode composed of a plurality of second wire electrodes provided so as to be opened and intersecting with the plurality of first wire electrodes is disposed in the solid, and the first An excitation signal is input to the wire electrode, and a measurement signal that reflects the capacitance, inductance, or conductance output from the second wire electrode is detected, and based on the measurement signal that reflects the capacitance, inductance, or conductance, Detecting a change in state of the solid

  In the third aspect of the present invention, the novel idea of detecting a change in the state of a solid by a measurement signal reflecting capacitance, inductance, or conductance obtained by arranging the above-described wire mesh sensor in a solid that does not flow. A solid state change detection method can be provided. That is, the state change of the solid can be observed easily and nondestructively over time, and the two-dimensional observation distribution can be appropriately changed according to the form of the solid, so that observation with a higher degree of freedom is performed. be able to.

  ADVANTAGE OF THE INVENTION According to this invention, the novel solid state change detection sensor and solid state change detection method which applied the wire mesh sensor can be provided.

It is a schematic diagram which shows the measuring device which has a wire mesh sensor. It is a fragmentary sectional view of a measuring device which has a wire mesh sensor, (a) is a fragmentary sectional view of the axial direction of a container, and (b) is a fragmentary sectional view of the radial direction of a container. It is the perspective view which showed the outline of the wire mesh sensor used in each Example. 2 is a graph showing the results of a solid phase / liquid phase / gas phase discrimination test in Example 1. FIG. 6 is a graph showing the results of a solid phase / gas phase discrimination test in Example 2.

(First embodiment)
Based on FIG.1 and FIG.2, the structure of the measuring apparatus which has the wire mesh sensor concerning one Embodiment of this invention and a wire mesh sensor is demonstrated.

  FIG. 1 is a schematic diagram showing a measuring device having a wire mesh sensor. FIG. 2 is a partial cross-sectional view of such a measuring device, (a) is a partial cross-sectional view in the axial direction of the container in which the wire mesh sensor is disposed in the measuring device, and (b) is a radial view of the container. It is a fragmentary sectional view.

  As shown in the drawing, a measuring device having a wire mesh sensor (hereinafter referred to as “measuring device 1”) is provided in a tubular container 10 for holding and holding a solid 11 to be measured, and in the tubular container 10, respectively. A plurality of wire mesh sensors 20, input means 30 for inputting the excitation signal PI to the wire mesh sensor 20, detection means 40 for detecting the measurement signals PO1 to PO4 output from the wire mesh sensor 20, and detection means 40 And an arithmetic processing means 50 for detecting the state change of the solid 11 by performing arithmetic processing on the detected measurement signals PO1 to PO4.

  In the measuring apparatus 1, when the solid 11 is accommodated in the tubular container 10, a plurality of wire mesh sensors 20 are disposed in the solid 11 and the state is maintained. That is, the measuring device 1 is a state change detection sensor of the solid 11 based on a novel idea that the wire mesh sensor 20 is disposed in the solid 11. With such a configuration, the measuring apparatus 1 can observe the state change of the solid 11 over time and easily and non-destructively.

  The tubular container 10 accommodates the solid 11 in which a plurality of wire mesh sensors 20 are disposed therein, and holds the state. The tubular container 10 only needs to be able to maintain the accommodation state without damaging the plurality of wire mesh sensors 20 disposed in the solid 11, and the material, shape, size, and the like are not particularly limited, and the solid container 11 or the measurement is not limited. It can be appropriately changed according to the device 1. In the present embodiment, although not shown, a cylindrical tubular container 10 having an opening for injecting the solid 11 on the upper surface in the axial direction and having the lower surface in the axial direction closed is used. However, when the state change of the solid 11 existing in the structure or the like is observed over time, the wire mesh sensor 20 is disposed in the solid 11 in advance, and the solid 11 is in such a state in the structure 11 or the like. Therefore, the tubular container 10 may not be used.

  Here, the solid 11 in the present embodiment is a non-flowing material, that is, a non-fluid material. Examples of the solid 11 that can be a measurement target of the measuring apparatus 1 include concrete, carbon fiber, methane hydrate, bentonite, and agar. In this embodiment, if it is the solid 11 in which the wire mesh sensor 20 can be arrange | positioned inside, the state change can be observed. Further, even if the solid 11 is a fluid when the wire mesh sensor 20 is disposed therein, it may be a non-fluid at the start of observation of the state change, and the concrete exemplified above corresponds to this. . A specific application example (application) of the measurement apparatus 1 will be described later.

  In addition, the state change of the solid 11 detected by the arithmetic processing unit 50 in the measuring device 1 is a state change in which a fluid is generated, collides, or mixed in the solid 11. The fluid is gas, liquid, or plasma, and a mixture thereof is also included in the concept of fluid in the present embodiment.

  The wire mesh sensor 20 includes an excitation electrode 22 including four first wire electrodes (transmitter wires) 21a to 21d, and four second wire electrodes (receiver wires) 23a to 23d functioning as measurement electrodes. It consists of a measurement electrode 24. In the present embodiment, the number of each wire electrode is not limited to this, and can be appropriately changed according to the measurement accuracy of the wire mesh sensor 20 and the form of the solid 11 to be measured.

  In the excitation electrode 22, the first wire electrodes 21a to 21d are arranged on the same plane in parallel with a space therebetween. In addition, the measurement electrode 24 includes second wire electrodes 23a to 23d arranged on the same plane in parallel with a space therebetween, and intersecting with the first wire electrodes 21a to 21d. The plane on which the excitation electrode 22 is disposed and the plane on which the measurement electrode 24 is disposed are different planes that exist in the tubular container 10 but are arranged in parallel at a certain interval. That is, the excitation electrode 22 and the measurement electrode 24 are arranged in a rectangular lattice shape with a separation distance from each other, thereby forming the wire mesh sensor 20. However, the wire mesh sensor 20 is not limited to the above structure as long as the excitation electrode 22 and the measurement electrode 24 do not interfere with each other and there is no problem in observing the state change of the solid 11. For example, the wires and the electrodes may not be arranged in parallel to each other, and the mesh shape may not be rectangular.

  Further, in the present embodiment, the plurality of wire mesh sensors 20 are arranged in the tubular container 10 in parallel to each other at a constant interval with respect to the depth direction of the tubular container 10. The number of the wire mesh sensors 20 can be appropriately changed according to the solid 11 to be measured, but it is preferable to dispose a plurality of wire mesh sensors 20 from the viewpoint of measurement accuracy.

  As described above, in the wire mesh sensor 20, the excitation electrode 22 and the measurement electrode 24 are close to each other but are not in contact with each other. Hereinafter, a portion where the wire electrodes of each electrode are close to each other is referred to as an intersection point for convenience. In the present embodiment, this intersection is a measurement point for the state change of the solid 11. Here, the measurement point exists in the space between the wire electrodes of each electrode. Specifically, as shown in FIG. 2A, for example, the measurement point [1, 1] is the first wire electrode 21a. And the second wire electrode 23a. That is, the wire mesh sensor 20 detects a change in the state of the solid 11 existing between the first wire electrode 21a and the second wire electrode 23a based on a two-dimensional measurement distribution.

  As shown in FIGS. 1 and 2, the measurement points ([1,1], [2,1], [3,1], [4,1]... [1,4] in the wire mesh sensor 20 are used. ], [2, 4], [3, 4], [4, 4]) are distributed in a plane where a pair of excitation electrodes 22 and measurement electrodes 24 exist, and a plurality of wire mesh sensors 20 are arranged. Many are formed in combination. That is, since the wire mesh sensor 20 is a multi-point electrode sensor, the state change of the solid 11 at each measurement point can be detected by a three-dimensional observation distribution. For example, it is possible to detect the presence or absence of a partial state change of the solid 11 by comparing the state change of the solid 11 for each wire mesh sensor 20 using a two-dimensional observation distribution. Therefore, the measurement apparatus 1 can observe the state change of the solid with higher accuracy.

  In the present embodiment, an embodiment in which the excitation electrode 22 composed of the first wire electrodes 21a to 21d and the measurement electrode 24 composed of the second wire electrodes 23a to 23d are used is adopted. You may employ | adopt the form using the excitation electrode which consists of wire electrodes 23a-23d, and the measurement electrode which consists of 1st wire electrodes 21a-21d.

  In this embodiment, stainless steel (SUS304) is used as a material for the first wire electrodes 21a to 21d and the second wire electrodes 23a to 23d. The material is not particularly limited as long as it is a material that does not deteriorate due to deformation or the like according to contact or measurement mode. Further, each wire electrode may be coated with a covering material made of an insulating material except for a region intersecting each other from the viewpoint of improving measurement sensitivity by reducing noise of the measuring device 1 and preventing interference. Here, the region excluding the regions that intersect each other in each wire electrode is a region that does not function as a measurement point and does not participate in detection of a measurement signal that reflects each parameter described later. Examples of the insulating material that can be used as a covering material include a fluororesin, a paraxylylene resin, and enamel. The material can be appropriately selected as necessary.

  The input unit 30 includes a power source 31, a changeover switch SP, and switches S1 to S4, and first wire electrodes 21a to 21d connected to the switches S1 to S4, respectively, serve as input lines. In the input means 30, the excitation signal PI is supplied from the power source 31 via the changeover switch SP, and the excitation signal PI is applied sequentially from the first wire electrode 21a in the first row by the switches S1 to S4. Note that the configuration of the input unit 30 is not limited to the above as long as the excitation signal PI can be supplied to the first wire electrodes 21a to 21d, and can be appropriately changed as necessary.

  The detection means 40 includes A / D converters 41a to 41d and a detection unit 42, and second wire electrodes 23a to 23d connected to the A / D converters 41a to 41d, respectively, serve as output lines. In the detection means 40, the excitation signals PI applied to the first wire electrodes 21a to 21d by the input means 30 are the intersections of the first wire electrodes 21a to 21d and the second wire electrodes 23a to 23d, that is, measurement. Point ([1,1], [2,1], [3,1], [4,1]... [1,4], [2,4], [3,4], [4,4 ] Are converted into measurement signals PO1 to PO4 reflecting the state change of the solid 11 and output through the A / D converters 41a to 41d, respectively, and the measurement signals PO1 to PO4 are detected by the detection unit 42. .

  In FIG. 1, only the measurement signals PO1 to PO4 are shown from the viewpoint of avoiding the complexity of the drawing, but actually, the excitation signal PI is converted into one measurement signal at one intersection, and this signal is It is detected by the detection unit 42. Each measurement signal is determined based on the detection timing. For example, the excitation signal PI applied to the first wire electrode 21a in the first row from the switch S1 is obtained at each intersection, that is, each measurement point ([4, 1], [3, 1], [2, 1], [1 , 1]) in this order. Therefore, the measurement signal first detected by the detection unit 42 is converted at the measurement point [4, 1]. However, the detection timing of each measurement signal can be appropriately changed by opening and closing the switches S1 to S4.

  Here, the measurement signals PO1 to PO4 reflecting the state change of the solid 11 reflect, for example, each parameter based on the state change of the solid 11, that is, a change in capacitance, inductance, or conductance. These parameters have eigenvalues depending on each substance, and the eigenvalues change according to changes in the state of the substance. In the present embodiment, the change in the state of the solid 11 is detected using such characteristics of the substance. Although details will be described later, a change in the state of the solid 11 can be detected by detecting changes in these parameters and performing arithmetic processing in the arithmetic processing means 50. Note that the configuration of the detection means 40 is not limited to the above as long as the measurement signals PO1 to PO4 can be output from the second wire electrodes 23a to 23d to the detection unit 42, and can be changed as necessary.

  The arithmetic processing unit 50 includes an arithmetic processing unit 51 and a storage unit 52. In the arithmetic processing unit 50, the arithmetic processing unit 51 performs arithmetic processing on the measurement signals PO1 to PO4 output from the detecting unit 40 based on various data stored in the storage unit 52, and based on this result, the state of the solid 11 Whether there is a change is determined.

  Here, the various data stored in the storage unit 52 include the capacitance, inductance, or conductance (hereinafter referred to as “solid parameters”) of the solid 11 to be measured, and a fluid is generated in the solid 11. , Capacitance, inductance or conductance (hereinafter referred to as “fluid parameters”) when the state changes due to collision or mixing. That is, the fluid parameter is a threshold value when the state of the solid 11 changes.

  The arithmetic processing unit 50 detects (determines) the presence of a different phase based on the threshold value of each parameter stored in the storage unit 52. That is, when a potential change is confirmed from the solid parameter, it is determined that the solid 11 has changed to a liquid or plasma due to generation, collision, or mixing of liquid or plasma in the solid 11. Further, when the fluid parameter becomes zero, it is determined that the state of the solid 11 has changed to a gas due to generation, collision, or mixing of the gas in the solid 11.

  In the present embodiment, the measurement parameter can also be indirectly measured by measuring the voltage (potential) and current without directly measuring the capacitance, inductance, or conductance, which are measurement parameters of the solid 11. That is, the capacitance, inductance, and conductance of the solid 11 can be calculated from the measured values by measuring the voltage (potential) and current. And the phase change of the solid 11 is detectable using the above-mentioned solid parameter and fluid parameter.

The capacitance Cp of the solid 11 can be calculated from the dielectric constant ε as shown in the following formula (1). The dielectric constant ε is a measured voltage value V, a measured current value I, and the following formulas (2) to (2) to It can be calculated by (4). However, in the following formulas (1) to (4), Cp is the capacitance of the solid 11, V is a measured voltage value of the solid 11, Q is an electric charge, d is a distance between the first and second wire electrodes, and ε is a solid. 11 is a dielectric constant, S is an area between the first and second wire electrodes, I is a measured current value of the solid 11, and t is time.
Cp = εS / d (1)
V = Qd / εS (2)
I = Q / t (3)
ε = Idt / VS (4)

The inductance L can be calculated by the measured voltage value V, the measured current value I, and the following equations (5) and (6). In the following formulas (5) and (6), V represents a measured voltage value of the solid 11, L represents an inductance of the solid 11, I represents a measured current value of the solid 11, and t represents time.
V = L (dI / dt) (5)
L = V (dt / dI) (6)

The conductance G can be calculated from the measured voltage value V, the measured current value I, and the following equations (7) and (8). In the following formulas (7) and (8), R represents the resistance value of the solid 11, V represents the measured voltage value of the solid 11, I represents the measured current value of the solid 11, and G represents the conductance.
R = V / I (7)
G = 1 / R = I / V (8)

  Further, a voltage (potential) or current is used as a measurement parameter of the solid 11, and the phase change of the solid 11 can be detected based on these fluctuations. In the present embodiment, a voltage (potential) is applied as a measurement parameter so that a temperature change of the solid 11 can be detected.

  Note that the configuration of the arithmetic processing unit 50 is not limited to the above as long as it can detect a change in the state of the solid 11 based on the measurement signals PO1 to PO4 output from the detection unit 40, and can be changed as needed. . For example, a state change of the solid 11 may be detected by applying a known capacitance (dielectric constant), inductance, or conductance measuring instrument.

  Next, the state change detection method of the solid 11 using the measuring device 1 will be described in detail.

  First, in the measuring apparatus 1, the solid 11 provided with the wire mesh sensor 20 is accommodated and held in the tubular container 10, the input means 30 is connected to the excitation electrode 22 side, and the detection means 40 is connected to the measurement electrode 24 side. The arithmetic processing means 50 is connected via

  Next, the excitation signal PI is supplied from the power source 31 of the input means 30 via the changeover switch SP, and the excitation signal PI is applied sequentially from the first wire electrode 21a in the first row by the switches S1 to S4. As a result, the excitation signal PI applied to each of the first wire electrodes 21a to 21d becomes an intersection (measurement point ([1, 1]) between the first wire electrodes 21a to 21d and the second wire electrodes 23a to 23d. , [2,1], [3,1], [4,1]... [1,4], [2,4], [3,4], [4,4]) The signals are converted into measurement signals PO1 to PO4 reflecting the change in state, and these signals are output from the second wire electrodes 23a to 23d to the A / D converters 41a to 41d.

  Next, the measurement signals PO1 to PO4 are A / D converted by the A / D converters 41a to 41d, and then output to the detection unit 42. These signals are detected by the detection unit 42 and output to the arithmetic processing unit 51.

  Next, the calculation processing unit 51 receives the measurement signals PO <b> 1 to PO <b> 4 reflecting the state change of the solid 11 output from the detection unit 42. Then, the arithmetic processing unit 51 performs arithmetic processing on the measurement signals PO <b> 1 to PO <b> 4 reflecting the state change of the solid 11 based on the solid parameters and fluid parameters (threshold values) stored in the storage unit 52. That is, when the parameter of the solid 11 based on the measurement signals PO1 to PO4 is equal to or greater than the threshold value or zero (including a case where it can be regarded as substantially zero), the arithmetic processing unit 51 determines that the solid 11 has a state change. . On the other hand, when the parameter of the solid 11 based on the measurement signals PO1 to PO4 is less than the threshold and not zero, the arithmetic processing unit 51 determines that the solid 11 has no state change. As a result, in the measuring apparatus 1, each intersection (measurement point ([1,1], [2,1], [3,1], [4,1]... [1,4], [2,4 ], [3, 4], [4, 4]), the presence or absence of a change in the state of the solid 11 can be detected.

  As described above, by using the measuring device 1 having the wire mesh sensor 20, the measurement signals PO1 to PO4 reflecting the capacitance, inductance, or conductance of the solid 11 are arithmetically processed, and the state change of the solid 11 is nondestructively performed over time. Can be observed easily and easily. Further, by arranging the wire mesh sensor 20 in the solid 11 that does not flow, the two-dimensional observation distribution can be appropriately changed according to the form of the solid, and observation with a higher degree of freedom can be performed. In addition, by using a plurality of wire mesh sensors 20, it is possible to detect a change in the state of the solid 11 with high accuracy by a three-dimensional observation distribution.

  Next, a specific application example (application) of the measurement apparatus 1 will be described in detail.

  The present invention uses a wire mesh sensor when a state change occurs due to generation, collision or mixture of gas, liquid or plasma in the solid by arranging the wire mesh sensor in the solid. It was completed based on the new knowledge that a state change can be detected in a non-destructive state.

  For example, it is possible to detect a change in the state of the concrete in a non-destructive manner by arranging a wire mesh sensor in advance in the concrete placed during construction. Specifically, when air or moisture enters a crack or the like caused by aging of concrete, a measurement signal reflecting the capacitance, inductance, or conductance of air or moisture is detected. Therefore, the capacitance, inductance, or conductance of concrete is detected. It can be distinguished from the reflected measurement signal, and a change in state occurring in the concrete can be detected. Similarly, when rust is generated in a reinforced concrete reinforcing bar, a measurement signal reflecting the capacitance, inductance, or conductance of the rust is detected, and a state change generated in the reinforcing bar can be detected. Thereby, deterioration diagnosis of concrete can be performed using a wire mesh sensor.

  The wire mesh sensor of the present invention can also be applied in the aircraft field. In recent years, carbon fiber (carbon fiber) has been used in civil aircraft, military aircraft, helicopters, and the like from the viewpoint of weight reduction, fatigue resistance, and heat resistance. In aircraft, carbon fiber is widely used for primary structure materials such as main wing, vertical and horizontal tail, secondary wing materials such as auxiliary wing, rudder and elevator, interior materials such as seats and tables, hydraulic cylinders, C / C brakes, etc. Although it is used, deterioration of each member leads to a serious accident, so it is necessary to grasp and replace in advance. However, since it is difficult to perform non-destructive deterioration diagnosis of these members, the wire mesh sensor of the present invention is useful for carbon fiber deterioration diagnosis in the aircraft field.

  Generally, the carbon fiber applied to an aircraft is a composite material using a carbon fiber as a reinforcing material and an epoxy resin as a base material. It is known that carbon fibers are easily oxidized and deteriorated under a high-temperature oxidizing atmosphere, and epoxy resins are easily deteriorated under a high-temperature and humid atmosphere. That is, similar to the deterioration diagnosis of concrete, the measurement signal reflecting the capacitance, inductance or conductance of the substance caused by the oxidative deterioration of the carbon fiber and / or the capacitance, inductance or the substance of the substance caused by the wet heat deterioration of the epoxy resin It is possible to detect a measurement signal reflecting conductance and detect a change in the state of the carbon fiber and / or epoxy resin. Thereby, the deterioration diagnosis of an aircraft member, especially a carbon fiber can be performed using a wire mesh sensor.

  The wire mesh sensor of the present invention can also be applied in gas production from methane hydrate. In general, in order to use methane hydrate present as a solid in the formation as energy, it is necessary to decompose methane hydrate and divide it into methane gas and water to recover only methane gas. However, it is not efficient to dig methane hydrate in deep sea formations as it is, so methane hydrate is decomposed into methane gas and water in the formation, and only methane gas is used, for example, almost the same principle and method as natural gas development Collect with equipment and equipment.

  However, in the above production method, since methane hydrate is decomposed in the formation, it is difficult to visualize the solid-liquid phase change of methane hydrate. Therefore, in the same way as the deterioration diagnosis of concrete, the measurement signal reflecting the capacitance, inductance, or conductance of methane gas generated by the solid-liquid phase change of methane hydrate is detected, and the state change generated in methane hydrate is detected. Can do. Thereby, generation | occurrence | production of the methane gas in a methane hydrate can be detected using a wire mesh sensor.

  In addition, the wire mesh sensor of the present invention can be applied to eruption prediction and crustal deformation estimation by detecting bentonite alteration. Here, bentonite is altered by structural changes at the molecular level caused by applying a certain amount of temperature and pressure over a long period of tens of millions of years to volcanic ash and lava deposited on the seabed and lake bottom. It is a mineral aggregate (a kind of clay mineral) obtained by this. By observing such bentonites over time and detecting alterations due to structural changes, it is possible to predict volcanic eruptions and estimate crustal deformation.

  However, it is difficult to visualize the phase change of bentonite using existing sensors. Therefore, for example, there is a possibility that the wire mesh sensor of the present invention is arranged at an arbitrary point near the volcano and eruption can be predicted from the alteration of bentonite at that point. In addition, it is possible to contribute to estimation of crustal deformation by installing the wire mesh sensor of the present invention in the formation where bentonite is generated, or on the seabed or lake bottom.

  That is, in the same manner as the deterioration diagnosis of concrete, it is possible to detect a measurement signal reflecting the capacitance, inductance or conductance of the altered bentonite caused by the phase change of bentonite, and to detect the state change caused in bentonite. Thereby, alteration in bentonite can be detected using a wire mesh sensor.

  The invention will now be described in more detail with reference to the following examples.

(Wire mesh sensor)
FIG. 3 is a perspective view showing an outline of the wire mesh sensor used in Example 1 and Example 2 described later. As shown in FIG. 3, the wire mesh sensor 100 is obtained by simplifying the wire mesh sensor 20 according to the present embodiment for an experiment, and includes four wire electrodes (transmitter wires 121a and 121b and receiver wires 122a and 122b. ) Alternately arranged in parallel and formed in a substantially square lattice shape (mesh shape) was prepared in the same manner as the measurement apparatus 1 except that it was disposed inside the container 110 holding the measurement object. In the wire mesh sensor 100, the transmitter wires 121a and 121b are input lines for inputting excitation signals, respectively, and the receiver wires 122a and 122b are output lines for outputting measurement signals (here, signals based on changes in voltage), respectively. . In each example, stainless steel (SUS304) was used as a material for the transmitter wires 121a and 121b and the receiver wires 122a and 122b. Further, in the wire mesh sensor 100, the portions where the wires are close to each other but are not in contact are defined as intersections ([1a, 1b], [1a, 2b], [2a, 1b], [2a, 2b]). These were taken as measurement points. In each embodiment, excitation signals are input to the transmitter wires 121a and 121b by input means (not shown), and these signals are output as measurement signals from the receiver wires 122a and 122b, respectively. The change in voltage with respect to the measurement time was measured.

Example 1
In Example 1, the above-described wire mesh sensor 100 was subjected to a solid phase / liquid phase / gas phase discrimination test based on the conditions (test parameters) shown in Table 1 below. Specifically, the container 110 of the wire mesh sensor 100 was previously filled with an agar aqueous solution, and the container 110 was filled with agar 130 (solid phase). Next, the upper part of the obtained agar 130 is filled with tap water, and the agar 130 between the transmitter wires 121a and 121b and the receiver wires 122a and 122b is cracked with a cutter knife at regular intervals to forcibly agar. 130 (solid phase), tap water (liquid phase) and air (gas phase) were mixed. Specifically, cracks were made at the center points of four measurement points in the vicinity of each measurement point ([1a, 1b], [1a, 2b], [2a, 1b], [2a, 2b]). And the change of the voltage in the wire mesh sensor 100 based on mixing a solid phase and a liquid phase / gas phase was measured, and the result was shown in FIG. Note that the arrows in FIG. 4 indicate that a forced crack was made in the agar 130 at that time. The measured voltage value is a measured value at an arbitrary measurement point selected from the four measurement points described above.

  As shown in FIG. 4, when the magnitude of the voltage value in the agar 130 is confirmed from about 26 seconds to 27 seconds before the forced cracking in the agar 130 (solid phase), there is no significant change in the voltage value here. The voltage value increased at the time of cracking. Moreover, in Example 1, although the agar 130 was cracked at regular time intervals, the crack was initially closed, but by repeatedly giving a crack, the crack in the agar 130 was difficult to close, and tap water (liquid phase) was internally contained. And air (gas phase) was mixed. Therefore, the minimum value of the voltage value tended to increase gradually.

  In Example 1, since the liquid phase (tap water) and the gas phase (air) were mixed in the solid phase (agar 130) in which the wire mesh sensor 100 was disposed, the solid phase voltage was changed. The minimum value has changed. That is, it was confirmed that by arranging the wire mesh sensor 100 in the solid phase and observing the change in the voltage value, it was possible to detect that the liquid phase and the gas phase, which are different phases, were mixed in the solid phase.

(Example 2)
In Example 2, the above-described wire mesh sensor 100 was subjected to a solid phase / gas phase discrimination test based on the conditions (test parameters) shown in Table 1. Specifically, as in Example 1, the container 110 of the wire mesh sensor 100 was filled with agar 130 (solid phase). Next, the transmitter wires 121a and 121b and the receiver wires 122a and 122b arranged on the agar 130 in the container 110 were taken out from the container 110 and moved to the outside, that is, in the gas phase. Then, each wire was disposed again on the agar 130 in the container 110, and the operation of replacing each wire from the agar 130 to the outside (gas phase) or from the outside to the agar 130 was repeated. And the change of the voltage in the wire mesh sensor 100 based on moving each wire between two phases was measured, and the result was shown in FIG. The arrows in FIG. 5 indicate that each wire is forcibly moved from the agar 130 to the outside at that time. The measured voltage value is a measured value at an arbitrary measurement point selected from the four measurement points described above.

  As shown in FIG. 5, when the magnitude of the voltage value at the agar 130 is confirmed until about 10 seconds before each wire arranged on the agar 130 (solid phase) in the container 110 is taken out, here the voltage value greatly changes. However, when each wire was forced to move from the agar 130 to the gas phase (external) and existed outside, the voltage value became a value close to substantially zero. However, when each wire exists in the agar 130, the reason why the voltage value decreases in time series is that the distance between the wires gradually increases. There is no relationship between 130 and external discrimination ability.

  In Example 2, the minimum value of the voltage value was changed by forcibly moving the solid phase (agar 130) provided with the wire mesh sensor 100 to the outside (gas phase). That is, it is possible to detect the phase change from the solid phase to the gas phase, which is a different phase, by arranging the wire mesh sensor 100 in the solid phase and observing the voltage value change in the same manner as in Example 1. Was confirmed.

  The present invention is particularly applicable to fields in which it is difficult to diagnose deterioration of each member and to visualize changes in the state of substances. For example, the present invention can be used in industrial fields such as concrete deterioration diagnosis (rust detection), carbon fiber deterioration diagnosis in the aircraft field, and detection of solid phase / liquid phase / gas phase changes such as methane hydrate and bentonite.

DESCRIPTION OF SYMBOLS 1 Measuring apparatus 10 Tubular container 11 Solid 20,100 Wire mesh sensor 21a, 21b, 21c, 21d 1st wire electrode 22 Excitation electrode 23a, 23b, 23c, 23d 2nd wire electrode 24 Measuring electrode 30 Input means 31 Power supply 40 Detection means 41a, 41b, 41c, 41d A / D converter 42 Detection section 50 Arithmetic processing means 51 Arithmetic processing section 52 Storage section 110 Container 121a, 121b Transmitter wire 122a, 122b Receiver wire 130 Agar SP changeover switch S1, S2, S3 , S4 switch

Claims (3)

Disposed in a solid,
An excitation electrode comprising a plurality of first wire electrodes spaced apart from each other, and a plurality of excitation electrodes provided spaced apart from each other and intersecting the plurality of first wire electrodes A wire mesh sensor having a measurement electrode comprising a second wire electrode;
Input means for inputting an excitation signal to the first wire electrode;
Detection means for detecting a measurement signal reflecting the capacitance, inductance or conductance output from the second wire electrode;
A solid state change detection sensor, comprising: an arithmetic processing unit that performs arithmetic processing on the measurement signal reflecting the capacitance, inductance, or conductance to detect a change in the solid state. The wire mesh sensor is disposed in the solid that does not flow;
The solid state change detection sensor according to claim 1, wherein the arithmetic processing unit detects a state change in which a fluid is generated, collides, or mixed in the solid. An excitation electrode comprising a plurality of first wire electrodes spaced apart from each other, and a plurality of excitation electrodes provided spaced apart from each other and intersecting the plurality of first wire electrodes A wire mesh sensor having a measurement electrode composed of a second wire electrode is disposed in the solid;
An excitation signal is input to the first wire electrode;
Detecting a measurement signal reflecting the capacitance, inductance or conductance output from the second wire electrode;
A solid state change detection method, wherein the solid state change is detected based on the measurement signal reflecting the capacitance, inductance, or conductance.