JP5656219B2 - Impedance measurement sensor and impedance measurement device - Google Patents

Description

  The present invention relates to an impedance measurement sensor and an impedance measurement device, and in particular, has a rod-shaped member, for example, the fluid film thickness formed on the surface of a fuel rod cladding tube in a nuclear reactor, and the state of the fluid on the surface. It is useful when applied to grasping the state of fluid flowing between two points between each fuel rod cladding tube.

  For example, in heat exchangers such as reactor fuel rod cladding tubes, condensers, and steam generators, it is important to know the thickness of the liquid film formed on the heat transfer surface when determining the amount of heat transfer. Conventionally, liquid film thickness fluctuations at a single point or line segment have been measured, but the liquid film subjected to shear from the gas phase is multidimensional, so the liquid film thickness distribution on the target surface can be captured in time series. Is desirable. As a method of measuring the time distribution and spatial distribution of the conductive liquid film thickness adhering to the surface of these structures, a liquid film thickness measuring liquid film is measured based on a change in the impedance of the conductive fluid between a pair of electrodes. A film thickness measuring method is known. In order to realize such a liquid film thickness measurement, a multi-point electrode liquid film thickness measurement sensor in which a large number of electrode pairs are formed has been proposed (for example, see Non-Patent Document 1).

  On the other hand, grasping the state of the cooling water flowing between the pipes of the heat exchanger including the fuel rod cladding tube etc. is important for the thermal design of the equipment. It is necessary to accurately grasp the water state (gas / liquid abundance, etc.) and behavior (flow velocity, flow direction). In order to accurately grasp the state of the cooling water (gas / liquid abundance, etc.) and behavior (flow velocity, flow direction), as much as possible in the cross section perpendicular to the flow direction of the cooling water (axial direction between the fuel rod covers) There is a need to collect information in many ways.

  Therefore, by grasping the state of the cooling water formed on the surface of the fuel rod cladding tube, etc. of the nuclear reactor, and the state of the cooling water flowing between the fuel rod cladding tube, etc. at the same time, the equipment It is thought that useful information on the thermal design of can be obtained. To further generalize, it is possible to grasp the state of the medium between the pipes at multiple points simultaneously with the state of the medium in the surface direction of the pipes as well as the fluid. In view of the above, it is considered that various useful information can be obtained.

Novel fluid dynamic instrumentation for mixing studies developed at ETH Zurich and PSI (The 13th International Topical Meeting on Nuclear Reactor Thermal Hydraulics Kanazawa City Isikawa Prefecture, Japan, September 27 October 2.2009

  The present invention is applied to a case where a medium existing between and around the rod-shaped members is a measurement object in view of the above-described prior art, and the state of the medium on the surface of the rod-shaped member and between and around the rod-shaped members. An object of the present invention is to provide an impedance measurement sensor and an impedance measurement device that can easily and accurately measure the state of an existing medium.

  A first aspect of the present invention that achieves the above object is an impedance measurement sensor that uses a medium existing between and around a plurality of rod-shaped members as a measurement object, and includes a first electrode comprising an excitation electrode and a measurement electrode A multi-point electrode for measuring impedance of the medium in contact with the excitation electrode and the measurement electrode, having a plurality of pairs and an insulating part for electrically insulating the excitation electrode and the measurement electrode Another electrode that functions as a measurement electrode or an excitation electrode by forming a second electrode pair with one of the excitation electrode or the measurement electrode so as to measure the impedance of the medium between the sensor and the excitation electrode or the measurement electrode And an impedance measurement sensor characterized by comprising:

  According to this aspect, the state of the medium in the surface direction of the multipoint electrode sensor can be detected by measuring the impedance of the medium between the excitation electrode and the measurement electrode by the multipoint electrode sensor having the first electrode, At the same time, the state of the medium between the multipoint electrode sensor and the other electrode can be measured by measuring the impedance of the medium between the multipoint electrode sensor forming the second electrode pair and the other electrode. . Here, the excitation electrode or the measurement electrode of the multipoint electrode sensor can function as one electrode of the second electrode pair.

  A second aspect of the present invention is an impedance measurement sensor for measuring a medium existing between and around a plurality of rod-shaped members, and includes a plurality of first electrode pairs each including an excitation electrode and a measurement electrode. A multi-point electrode sensor for measuring the impedance of the medium that is in contact with the excitation electrode and the measurement electrode by having an insulating portion that electrically insulates the excitation electrode and the measurement electrode; A point electrode sensor is provided with an individual electrode that functions as an excitation electrode or a measurement electrode provided independently of the excitation electrode and the measurement electrode, and a second electrode together with the individual electrode so as to measure the impedance of the medium between the individual electrode and the second electrode. An impedance measurement sensor having a measurement electrode that forms an electrode pair or another electrode that functions as an excitation electrode.

According to this aspect, the function similar to that of the impedance measurement sensor described in the first aspect can be obtained by causing the individual electrode of the multipoint electrode sensor to function as one electrode of the second electrode pair.

  A third aspect of the present invention is the impedance measurement sensor according to the first or second aspect, wherein the impedance measurement sensor is held at the same potential as the reference potential of the excitation electrode and the insulation between the excitation electrode and the measurement electrode is performed. The impedance measurement sensor further includes a ground electrode insulated at the portion.

  According to this aspect, the influence of disturbance can be removed as much as possible. As a result, the accuracy of predetermined impedance measurement can be improved.

  According to a fourth aspect of the present invention, in the impedance measurement sensor according to any one of the first to third aspects, the multipoint electrode sensor is disposed on an outer peripheral surface of the rod-shaped member. It is in the characteristic impedance measurement sensor.

  According to this aspect, the state of the medium on the outer peripheral surface of the rod-shaped member can be measured satisfactorily.

  According to a fifth aspect of the present invention, in the impedance measurement sensor according to any one of the first to third aspects, the multipoint electrode sensor is disposed on a wall surface surrounding the periphery of the rod-shaped member. It is in the impedance measurement sensor characterized by this.

  According to this aspect, the state of the medium on the wall surface can be measured satisfactorily.

  According to a sixth aspect of the present invention, in the impedance measurement sensor according to any one of the first to fifth aspects, the other electrode is formed of another rod-shaped member. It is in.

  According to this aspect, the other rod-shaped member can be used as one electrode of the second electrode pair.

  According to a seventh aspect of the present invention, in the impedance measurement sensor according to any one of the first to fifth aspects, the other electrode is another multi-point electrode sensor disposed on another rod-shaped member. The impedance measurement sensor is characterized by being formed of a measurement electrode, an excitation electrode, or an individual electrode.

  According to this aspect, the measurement electrode, excitation electrode, or individual electrode of another multipoint electrode sensor can be used as one electrode of the second electrode pair.

  According to an eighth aspect of the present invention, in the impedance measurement sensor according to any one of the first to fifth aspects, the other electrode is formed of a wire disposed between the rod-shaped members. It is in the characteristic impedance measurement sensor.

  According to this aspect, the wire can be one electrode of the second electrode pair.

  According to a ninth aspect of the present invention, in the impedance measurement sensor according to the eighth aspect, the wire includes a plurality of wires arranged in parallel to each other.

  According to this aspect, the distance between the excitation electrode and the measurement electrode of the second electrode pair can be reduced. That is, for example, by arranging two wires, the local impedance near the surface of the rod-shaped member can be measured with higher accuracy than when each wire is used as one electrode.

  According to a tenth aspect of the present invention, in the impedance measurement sensor according to the eighth or ninth aspect, the wires are separated from each other by a predetermined distance, and the first wire and the second wire intersect with each other. The impedance measurement sensor is characterized by comprising

  According to this aspect, both the first wire and the second wire, between the first wire and the multipoint electrode sensor, or between the second wire and the multipoint electrode are the second. It can be a measurement point by an electrode pair.

  An eleventh aspect of the present invention is the impedance measurement sensor according to any one of the eighth to tenth aspects, wherein the wires are arranged in a plurality of positions with respect to the axial direction of the rod-shaped member. It is in the impedance measurement sensor characterized by having.

  According to this aspect, the impedance of the medium existing between the rod-shaped members can be measured at a plurality of locations in the axial direction of the rod-shaped member.

  According to a twelfth aspect of the present invention, in the impedance measurement sensor according to the eleventh aspect, the rod-shaped member has an insulating portion formed in the middle of each axial direction. is there.

  According to this aspect, it is possible to prevent mutual interference of impedance measurement sensors respectively formed at a plurality of locations in the axial direction of the rod-shaped member.

The thirteenth aspect of the present invention provides
In the impedance measurement sensor according to any one of the first to twelfth aspects,
In the multi-point electrode sensor, the insulating portion is surrounded by a ground electrode that is insulated by the insulating portion between the excitation electrode and the measurement electrode to form independent insulating regions, In the impedance measurement sensor, only the insulating region is formed between the excitation electrode and the measurement electrode in the same electrode pair among the electrode pairs.

  According to this aspect, the excitation electrode and the measurement electrode of the multipoint electrode sensor forming the first electrode pair form the electrode pair in the insulating region that is made independent by being surrounded by the ground region. In addition, since there is no ground region between each excitation electrode and measurement electrode, the influence of the other electrode pairs from the excitation electrode is eliminated, and independent lines of electric force unique to each electrode pair are measured from the excitation electrode. It is formed toward the electrode. That is, the sensitivity of each electrode pair is the same for any electrode pair, and it can be prevented from being affected by adjacent electrode pairs.

  A fourteenth aspect of the present invention is the impedance measurement sensor according to any one of the first to thirteenth aspects, and the first electrode pair by the medium existing on the surface of the first electrode pair. Based on the impedance between the excitation electrode and the measurement electrode, the abundance of a plurality of substances in the medium having different impedances existing at the first measurement position is calculated, and the medium measured by the second electrode pair is calculated. And an arithmetic processing unit that calculates the abundances of a plurality of substances in the medium having different impedances at the second measurement position based on the impedance through the impedance measurement apparatus.

  According to this aspect, the state of the medium in the surface direction of the multipoint electrode sensor is set with the first electrode pair, and the state of the medium existing between the multipoint electrode sensor and another point is set with the second electrode pair. It can be measured simultaneously.

  According to the present invention, the state of the medium in the surface direction of the multipoint electrode can be detected by measuring the impedance of the medium between the excitation electrode and the measurement electrode by the multipoint electrode sensor, and at the same time, the multipoint electrode sensor The state of the medium between the multipoint electrode sensor and the other electrode can be measured by measuring the impedance of the medium between the electrode and the other electrode.

  As a result, information representing the state of the medium in the surface direction of the multipoint electrode and information representing the state of the medium between the multipoint electrode sensor and the other electrode can be obtained simultaneously.

  At this time, since the excitation electrode or measurement electrode of the multipoint electrode sensor functions as one electrode of the second electrode pair, the apparatus configuration can be simplified correspondingly.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic diagram which shows the impedance measurement sensor which concerns on the 1st Embodiment of this invention, (a) is the figure seen planarly, (b) is the figure which looked at (a) from the side, (c) is the first It is a figure which expands and shows the measurement electrode part of the multipoint electrode sensor used as one electrode of 2 electrode pairs. It is a schematic diagram which shows the impedance measurement apparatus which has an impedance measurement sensor shown in FIG. It is a wave form diagram which shows the waveform of each part of FIG. It is a schematic diagram which shows the impedance measurement sensor which concerns on the 2nd Embodiment of this invention, (a) is the figure seen from the side surface, (b) is the multipoint electrode sensor used as one electrode of a 2nd electrode pair. It is a figure which expands and shows an individual electrode part. It is the schematic diagram which shows the impedance measurement sensor which concerns on the 3rd Embodiment of this invention, (a) is the figure seen planarly, (b) is the figure which looked at (a) from the side. It is the schematic diagram which shows the impedance measurement sensor which concerns on other embodiment of this invention, (a) is the figure seen planarly, (b) is the figure which looked at (a) from the side. It is the schematic diagram which shows the impedance measurement sensor which concerns on other embodiment of this invention, (a) is the figure seen planarly, (b) is the figure which looked at (a) from the side. It is the schematic diagram which shows the impedance measurement sensor which concerns on other embodiment of this invention, (a) is the figure seen planarly, (b) is the figure which looked at (a) from the side.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each embodiment, the same parts are denoted by the same reference numerals, and redundant description is omitted.

<First Embodiment>
1A and 1B are schematic views showing an impedance measurement sensor according to a first embodiment of the present invention. FIG. 1A is a plan view, and FIG. 1B is a side view of FIG. As shown in both figures, the multipoint electrode sensor 1 in this embodiment is disposed on one outer peripheral surface of a rod-shaped member 2, and includes a plurality of first electrode pairs 3 including excitation electrodes 4 and measurement electrodes 5. And a ground electrode 6 held at the same potential as the reference potential of the excitation electrode 4 and an insulating portion 7 that electrically insulates the excitation electrode 4, the measurement electrode 5, and the ground electrode 6. Thus, the impedance of the fluid that is a medium in contact with the excitation electrode 4 and the measurement electrode 5 is measured. That is, this embodiment is an impedance measurement sensor that detects information related to the fluid, such as the abundance ratios of a plurality of types of fluids that form the membrane fluid formed on the surface of the rod-shaped member 2 by the first electrode pair 3. .

  The other electrode in this embodiment is formed by the first wire electrode 9. That is, the first wire electrode 9 is a measurement electrode so as to measure the impedance of the fluid between the excitation electrode 4 or the measurement electrode 5 (in the present embodiment, the measurement electrode 5 as shown in FIG. 1C). The second electrode pair 8 is formed between the second electrode pair 8 and the second electrode pair 8.

  The rod-shaped member 2 has an existing structure in which a large number of the rod-shaped members 2 are gathered so that the axial directions are aligned in the same direction, and fluid flows along the respective axial directions between the rod-shaped members 2. . In this embodiment, each rod-like member 2 is made of a conductive material so as to function as a ground electrode held at the same potential as the reference potential of the excitation electrode, measurement electrode, or excitation electrode. A fuel rod cladding tube in a nuclear reactor is a suitable example of this type of rod-shaped member 2.

  In this embodiment, in addition to the first wire electrode 9, the second wire electrode 10 is also provided. Here, the second wire electrode 10 is separated from the first wire electrode 9 by a predetermined distance in the axial direction of the rod-shaped member 2 and is rod-shaped in a square lattice shape so as to intersect the first wire electrode 9. It is disposed between the members 2. Therefore, in this embodiment, the intersection between the first wire electrode 9 and the second wire electrode 10, between the first wire electrode 9 and the rod-shaped member 2, the second wire electrode 10 and the rod-shaped member 2, Also, the impedance measurement point based on the fluid can be selected.

  According to this embodiment, the impedance of the fluid between the excitation electrode 4 and the measurement electrode 5 is measured by the multipoint electrode sensor 1 having the first electrode pair 3 and the state of the fluid in the surface direction of the multipoint electrode sensor 1 ( For example, the film thickness, wave speed, etc.) can be detected. At the same time, by measuring the impedance of the fluid between the measurement electrode 5 of the multipoint electrode sensor 1 forming the second electrode pair 8 and the first wire electrode 9 which is another electrode, the cross section intersecting the flow direction It is possible to detect the state of the fluid at multiple points (for example, the abundance ratio of gas and liquid in the fluid).

  Here, the electrode on the multi-point electrode sensor 1 side of the second electrode pair 8 is formed by the excitation electrode 4, and the other electrode of the second electrode pair 8 is formed by the second wire electrode 10. Of course, it is possible, and in each of these cases, the same operation and effect as in the present embodiment can be obtained. Further, the other electrode of the second electrode pair 8 can be formed by the first and second wire electrodes 9 and 10. In this case, the impedance between the first and second wire electrodes 9, 10 and the multipoint electrode sensor 1 can be measured.

  Since the impedance measurement sensor according to the present embodiment includes the first and second wire electrodes 9 and 10 and the rod-shaped member 2 in addition to the multipoint electrode sensor 1, the following is used as a sensor of the impedance measurement device. Such usage modes of the three modes are also conceivable. A first mode in which the first wire electrode 9 functions as an excitation electrode, the second wire electrode 10 functions as a measurement electrode, and the rod-shaped member 12 functions as a ground electrode, the rod-shaped member 12 functions as an excitation electrode, and first and second wires There are three types: a second mode in which the electrodes 9 and 10 function as measurement electrodes, and a third mode in which the first case and the second case are selectively switched.

  FIG. 2 is a schematic diagram mainly relating to the first electrode pair of the impedance measurement sensor according to the present embodiment, and FIG. 3 is a waveform diagram showing waveforms of respective parts in FIG. 2 that are the same as those in FIG. 1 are assigned the same reference numerals, and redundant descriptions are omitted.

  As shown in FIG. 2, a number of first electrode pairs 3 formed by the excitation electrode 4 and the measurement electrode 5 are signal lines 26 extending in the vertical direction in the figure (the numbers on the right are numbers corresponding to the respective columns). .) And a signal line 27 (the upper number is a number corresponding to each row) extending in the horizontal direction in the drawing. Here, each excitation electrode 4 is connected to the signal line 26, and each measurement electrode 5 is connected to the signal line 27. In this embodiment, the excitation electrode 4 belonging to a specific row (fourth row in the figure) is configured as one electrode of the second electrode pair 8. Therefore, the excitation electrode 4 constituting the second electrode pair 8 detects a signal using the first wire electrode 9 as a measurement electrode. Here, when making the excitation electrode 4 function as one electrode of the second electrode pair 8, the measurement electrode 5 stops functioning as an electrode. In the case shown in FIG. 2, the measurement electrode 5 in the first electrode pair 3 belonging to the fourth row is not used, so the display in the figure is omitted, but the first electrode pair 3 in the fourth row. Are configured in the same manner as the first electrode pairs 3 in the other rows. Therefore, the external circuit (switch, power supply, A / D converter, PC, etc.) is switched so that the excitation signal is input to and output from the signal line 27 and the output signal is input to and output from the signal line 26 to excite the first wire electrode 9. It is also possible to function as an electrode.

  Thus, a state in which a liquid film of conductive fluid (for example, water) is formed on the surface of the multipoint electrode sensor 1 or a state in which liquid is flowing between the multipoint electrode sensor 1 and the first wire electrode 9. When one of the signal lines 26 is sequentially selected from the first column by the switches S1, S2, S3, and S4 that are turned on / off by the pulse signal shown in FIG. 3, the excitation electrode connected to the selected column. 4, a predetermined excitation signal SI is supplied from the power supply 25. In this embodiment, the excitation signal SI is a bipolar pulse signal whose polarity is inverted by switching the switch SP.

  When the excitation signal SI is supplied to the column selected by the pulse signal, the measurement signal SO corresponding to the state with the measurement electrode 5 or the state with the first wire electrode 9 is sent from the signal line 27 of each row. Obtained and supplied to a personal computer (personal computer; the same applies hereinafter) 31 functioning as an arithmetic processing unit via each A / D converter 30. Here, the state between the measuring electrode 5 is a state of a fluid film or the like formed on the surface of the multipoint electrode sensor 1, and this state changes depending on the liquid film thickness or the like. The state between the first wire electrode 9 is a state such as a gas-liquid two-phase flow in the fluid between the first wire electrode 9 and the multipoint electrode sensor 1, and this state is a gas state. Varies with the abundance ratio of gas to liquid in a liquid two-phase flow. That is, according to the present embodiment, information on the fluid in the surface direction of the multipoint electrode sensor 1 is obtained by the first electrode pair 3, and the multipoint electrode sensor 1 and the first wire electrode 9 are obtained by the second electrode pair 8. The fluid information between the two can be detected. FIG. 3 shows the waveform of each part.

<Second Embodiment>
4A and 4B are schematic views showing an impedance measurement sensor according to the second embodiment of the present invention, where FIG. 4A is a side view, and FIG. 4B is a multi-point that is one electrode of the second electrode pair. It is a figure which expands and shows the individual electrode part of an electrode sensor. In both figures, the same parts as those in FIG.

  As shown in FIG. 4, in this embodiment, the electrode on the multi-point electrode sensor 11 side constituting one of the second electrode pair 18 is constituted by an individual electrode 16 provided separately from the excitation electrode 4 and the measurement electrode 5. is there. The individual electrode 16 is provided via an insulating part 17. That is, in this embodiment, the excitation electrode 4 or the measurement electrode 5 in the first embodiment is replaced with the individual electrode 16, and one electrode forming the second electrode pair 18 is the individual electrode 16. Only the point is different. Including the impedance measuring apparatus using this embodiment, the functions, operations, effects, etc. can be considered in the same manner as in the first embodiment.

  However, according to the present embodiment, the measurement system constituted by the first electrode pair 3 and the measurement system constituted by the second electrode pair 18 can be completely divided into two systems.

<Third Embodiment>
FIGS. 5A and 5B are schematic views showing an impedance measurement sensor according to the third embodiment of the present invention. FIG. 5A is a plan view, and FIG. 5B is a side view of FIG. In both figures, the same parts as those in FIG.

  As shown in FIG. 5, the multipoint electrode sensor 31 in this embodiment is disposed so as to surround the plurality of rod-shaped members 2. In the case of this embodiment, one electrode of the second electrode pair may be any of the rod-shaped member 2 and the first and / or second wire electrodes 9 and 10. The multipoint electrode sensor 31 itself may be of the same configuration as the multipoint electrode sensor 1 or the multipoint electrode sensor 11 having the individual electrodes 16. That is, in the former case, either the excitation electrode 4 or the measurement electrode 5 of the multipoint electrode sensor 1 is used, and in the latter case, the individual electrode 16 of the multipoint electrode sensor 11 is connected to the other electrode of the second electrode pair. Become. Accordingly, the basic operation and effect including the impedance measuring apparatus using this embodiment can be considered exactly the same as those of the first and second embodiments.

  According to this embodiment, the fluid information in the surface direction of the wall surface formed by the multipoint electrode sensor 31 is measured, and the fluid state between the multipoint electrode sensor 31 and one electrode is good with the second electrode pair. Can be measured.

<Other embodiments>
Although the present invention has been specifically described together with the respective embodiments as described above, the present invention is not necessarily limited to the first to third embodiments. A second electrode pair is formed by a multipoint electrode sensor having a plurality of first electrode pairs and the other electrode paired with the excitation electrode, measurement electrode or individual electrode of the multipoint electrode sensor as one electrode. The first electrode pair is configured to measure the impedance of the medium in the surface direction of the multipoint electrode sensor, and the second electrode pair is configured to measure the impedance of the medium between the multipoint electrode sensor and another electrode. If there is, it is included within the scope of the technical idea of the present invention.

  Specifically, the following other embodiments are possible. Although the multipoint electrode sensors 1, 11, and 31 in the first to third embodiments shown in FIGS. 1 and 4 each have the ground electrode 6, this is not always necessary. However, when the ground electrode 6 is provided, the effect of disturbance can be removed as much as possible, and an effect that high-precision impedance measurement can be performed is obtained.

  In addition, although two wire electrodes of the first wire electrode 9 and the second wire electrode 10 are provided, any one of them may be provided. Furthermore, although the first wire electrode 9 and the second wire electrode 10 are arranged in a plurality of stages (three stages in the figure) in the axial direction of the rod-shaped member 2, at least one stage may be provided.

  Furthermore, the first and second wire electrodes 9 and 10 are each formed as a single piece, but as shown in FIG. 6, these are formed by two first and second wire electrodes (9A and 9B), ( 10A, 10B). In this case, since the distance between the excitation electrode such as the second electrode pair 8 and the measurement electrode can be reduced, the local impedance near the surface of the rod-shaped member 2 can be measured with high accuracy.

  Furthermore, in the first to third embodiments, the first and second wire electrodes 9 and 10 are arranged in a square lattice shape in the cross section of the rod-shaped member 2, but the present invention is not limited to this. Depending on the arrangement state of the rod-shaped member 2, other arrangement forms such as a staggered arrangement may be used, and depending on the case, the rod-shaped member 2 may be arranged in the axial direction.

  In short, the number of wire electrodes, the position of placement, the manner of placement, and the number of steps may be appropriately determined in consideration of the position where necessary impedance information is obtained.

  In the case where the first and second wire electrodes 9 and 10 are arranged in multiple stages, an insulating portion may be formed in the middle of the rod-shaped member 2 in the axial direction and defining the boundary of each stage. . In this case, mutual interference of impedance measurement sensors formed at a plurality of locations in the axial direction of the rod-shaped member 2 can be prevented.

  In the first and second embodiments, the other electrodes of the second electrode pair 8 and 18 can be not only the wire electrodes 9 and 10 but also the rod-shaped member 2. Further, as shown in FIG. 7, a multipoint electrode sensor 1 (may be a multipoint electrode sensor 11, the same shall apply hereinafter) is provided on the outer peripheral surface of the adjacent rod-shaped member 2. The excitation electrode 4 or the measurement electrode 5 may be used as another electrode of the second electrode pair 8.

  In the third embodiment, as shown in FIG. 8, the multipoint electrode sensor 1 is disposed on the outer peripheral surface of the rod-shaped member 2 facing the multipoint electrode sensor 31, and the multipoint electrode sensor 1 is excited. The electrode 4, the measurement electrode 5, etc. may be other electrodes of the second electrode pair.

  Furthermore, although the above embodiment has been described by taking a fluid as an example of a measurement target, it is not necessary to limit the measurement target to a fluid. Even a solid such as a jelly-like substance can be measured.

  The present invention measures the impedance caused by the fluid flowing between the rod-shaped members, which is a rod-shaped member assembly in which a large number of rod-shaped members are assembled, for example, in the industrial field handling nuclear fuel assemblies. It can be used effectively.

DESCRIPTION OF SYMBOLS 1, 11, 31 Multipoint electrode sensor 2 Rod-shaped member 3 1st electrode pair 4 Excitation electrode 5 Measurement electrode 6 Ground electrode 7 Insulation part 8, 18 2nd electrode pair 9 1st wire electrode 10 2nd wire electrode

Claims (14)

An impedance measurement sensor for measuring a medium existing between and around a plurality of rod-shaped members,
A plurality of first electrode pairs each including an excitation electrode and a measurement electrode; and an insulating portion that electrically insulates between the excitation electrode and the measurement electrode, and is in contact between the excitation electrode and the measurement electrode. A multipoint electrode sensor for measuring the impedance of the medium;
One of the excitation electrode or measurement electrode and another electrode that forms a second electrode pair and functions as the measurement electrode or excitation electrode so as to measure the impedance of the medium between the excitation electrode or the measurement electrode An impedance measurement sensor characterized by that. An impedance measurement sensor for measuring a medium existing between and around a plurality of rod-shaped members,
A plurality of first electrode pairs each including an excitation electrode and a measurement electrode; and an insulating portion that electrically insulates between the excitation electrode and the measurement electrode, and is in contact between the excitation electrode and the measurement electrode. A multipoint electrode sensor for measuring the impedance of the medium;
An individual electrode that functions as an excitation electrode or a measurement electrode provided independently from the excitation electrode and the measurement electrode in the multipoint electrode sensor;
An impedance measurement sensor comprising: a measurement electrode that forms a second electrode pair together with the individual electrode so as to measure an impedance of the medium between the individual electrode and another electrode that functions as an excitation electrode. In the impedance measurement sensor according to claim 1 or 2,
The impedance measurement sensor further comprising a ground electrode which is held at the same potential as the reference potential of the excitation electrode and is insulated from the excitation electrode and the measurement electrode by the insulating portion. In the impedance measurement sensor according to any one of claims 1 to 3,
The multi-point electrode sensor is disposed on an outer peripheral surface of the rod-shaped member. In the impedance measurement sensor according to any one of claims 1 to 3,
The multipoint electrode sensor is disposed on a wall surface surrounding the rod-shaped member, and is an impedance measurement sensor. In the impedance measurement sensor according to any one of claims 1 to 5,
The impedance measurement sensor according to claim 1, wherein the other electrode is formed of another rod-shaped member. In the impedance measurement sensor according to any one of claims 1 to 5,
The other electrode is formed of a measurement electrode, an excitation electrode or an individual electrode of another multipoint electrode sensor disposed on another rod-shaped member. In the impedance measurement sensor according to any one of claims 1 to 5,
The other electrode is formed of a wire disposed between the rod-shaped members. The impedance measurement sensor according to claim 8,
The impedance measurement sensor according to claim 1, wherein the wire includes a plurality of wires arranged in parallel to each other. In the impedance measurement sensor according to claim 8 or 9,
An impedance measuring sensor characterized in that the wires are made up of a first wire and a second wire that are separated from each other by a predetermined distance and cross each other. In the impedance measurement sensor according to any one of claims 8 to 10,
An impedance measuring sensor, wherein the wires are arranged in a plurality of positions in a plurality of locations with respect to the axial direction of the rod-shaped member. The impedance measurement sensor according to claim 11,
An impedance measuring sensor, wherein an insulating portion is formed in the rod-shaped member in the middle of each axial direction. In the impedance measurement sensor according to any one of claims 1 to 12,
In the multi-point electrode sensor, the insulating portion is surrounded by a ground electrode that is insulated by the insulating portion between the excitation electrode and the measurement electrode to form independent insulating regions, An impedance measurement sensor, wherein only the insulating region is formed between the excitation electrode and the measurement electrode in the same electrode pair among the electrode pairs. The impedance measurement sensor according to any one of claims 1 to 13,
A plurality of substances in the medium having different impedances present at the first measurement position based on the impedance between the excitation electrode and the measurement electrode in the first electrode pair due to the medium existing on the surface of the first electrode pair The abundance of a plurality of substances in the medium having different impedances at the second measurement position is calculated based on the impedance through the medium measured by the second electrode pair. And an arithmetic processing unit for performing the impedance measurement.