A vertical flow capacitance detection device

Abstract

The application discloses a vertical flow capacitance detection device, which comprises a fluid to be detected, a detection unit, an outer skeleton and a measuring circuit, characterized in that the detection unit is internally installed in the outer skeleton, the detection unit is composed of an electrode unit and an inner skeleton, the electrode unit is installed on the inner skeleton, the electrode unit is composed of a plurality of electrode plates arranged in parallel, a plurality of through holes are formed in the electrode plates, and the fluid to be detected flows through the through holes on the electrode plates and sequentially passes through each electrode plate. The vertical flow capacitance sensor adopted by the application can be designed into a capacitance sensor array by using electrode plates with different through hole diameters, so that different parameters of the fluid can be measured at the same time, or the distribution of the fluid parameters in the pipeline can be measured, which cannot be achieved by the prior art.

Description

Technical Field

[0001] This invention relates to the field of online measurement technology for industrial fluids, and more particularly to a vertical flow capacitance detection device. Background Technology

[0002] Planar capacitive sensors are widely used in measuring the electrical properties of various fluids (liquids or gases). However, commercially available planar capacitive sensors generally employ a parallel flow design, meaning the flow direction of the measured fluid is parallel to the surface of the electrode plates. However, this design is limited by the spacing between the electrode plates, severely restricting the sensor's detection sensitivity. Secondly, parallel flow capacitive sensors struggle to separate and measure components with different physical states within the fluid, and it's impossible to assemble them into an array for simultaneous measurement of multiple fluid parameters. Thirdly, the electric field of a parallel flow capacitive sensor is a continuous, uniform electric field, with very small leakage electric fields at the electrode plate edges, which cannot be used to increase measurement sensitivity. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a vertical flow capacitance detection device.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A vertical flow capacitance detection device includes a fluid to be tested, a detection unit, an outer frame, and a measurement circuit. The detection unit is installed inside the outer frame and consists of an electrode unit and an inner frame. The electrode unit is mounted on the inner frame and consists of multiple parallel electrode plates with multiple through holes. The fluid to be tested flows through the through holes on the electrode plates and passes sequentially through each electrode plate. By changing the number and diameter of the through holes on different electrode plates, the detection area between the electrode plates and the area before and after the fluid flows into the detection area have different fluid pressures and flow field distributions, thereby achieving the differentiation and high-precision measurement of different components of the fluid to be tested.

[0006] Preferably, the electrode plate is planar or curved, and the through holes on the electrode plate are formed by perforating a metal plate or by a metal mesh or sintered metal filter made of metal wire.

[0007] Preferably, the electrode plate is composed of metal warp and metal weft cross-woven or bonded, the surfaces of the metal warp and metal weft are coated with an insulating layer, the metal warp and metal weft are electrically connected to metal leads respectively, and the two metal leads are electrically connected to the measuring circuit respectively.

[0008] Preferably, the spacing t between the electrode plates satisfies the following relationship with the average through-hole diameter d1 on the first electrode plate and the average through-hole diameter d2 on the second electrode plate:

[0009] t <= 10*(d1+d2).

[0010] Preferably, the electrode unit is configured to consist of a first cylindrical metal cup and a second cylindrical metal cup nested together, with the first cylindrical metal cup located on the outer side connected to the negative terminal or ground of the measurement circuit, and the second cylindrical metal cup located on the inner side connected to the positive terminal of the measurement circuit.

[0011] Preferably, the electrode unit is configured to consist of three parallel electrode plates, wherein the middle electrode plate is connected to the positive terminal of the measurement circuit, and the electrode plates on both sides are connected to the negative terminal of the measurement circuit or ground.

[0012] Preferably, the outer frame is provided with a fluid channel, and multiple detection units are installed sequentially in the fluid channel. The diameter of the through holes of the electrode plates of the detection units gradually decreases with the direction of fluid flow.

[0013] Preferably, the outer frame is provided with multiple fluid channels, and each fluid channel is equipped with a detection unit. The electrode plates on the detection units located in different fluid channels have the same or different through hole diameters.

[0014] A method of using a vertical flow capacitance detection device includes the following steps:

[0015] S1. A fluid channel is set on the outer frame, and three detection units are set in sequence in the fluid channel. The average through hole diameters of the two electrode plates in the first detection unit are 0.5 mm and 0.2 mm, respectively. The average through hole diameters of the electrode plates in the second detection unit are 0.2 mm and 0.1 mm, respectively. The average through hole diameters of the electrode plates in the third detection unit are 0.1 mm and 0.07 mm, respectively.

[0016] S2. All detection units are installed such that the direction of the through-hole diameter from large to small is consistent with the direction of fluid flow;

[0017] S3. Install the outer frame in the gas channel to be tested, and measure the three output capacitance values ​​C1, C2, and C3 of the three detection units through the measuring circuit.

[0018] S4. Calculate the changes in the three output capacitor values ​​C1, C2, and C3 from their initial values;

[0019] S5. Based on the changes in readings and time response curves of the three detection units, determine the concentrations of three solid pollutants in the air with particle sizes of 0.2-0.5 mm, 0.1-0.2 mm, and 0.07-0.1 mm, respectively.

[0020] S6. Measure the three output impedance values ​​Z1, Z2, and Z3 of the three detection units through the measurement circuit, calculate the changes in the three output impedance values ​​Z1, Z2, and Z3 from the initial values, calculate the ratio of the capacitance change to the impedance change, and determine the polarity and conductivity of the solid pollutant.

[0021] A method of using a vertical flow capacitance detection device includes the following steps:

[0022] S1. Three fluid channels are evenly arranged at the bottom, middle and top of the outer frame, and detection units with the same through hole diameter are installed in each channel. The average through hole diameter of the first electrode plate in the detection unit is 0.2 mm, and the average through hole diameter of the second electrode plate in the detection unit is 0.1 mm.

[0023] S2. Insert the outer frame into the oil delivery pipeline so that the oil to be tested flows through three fluid channels simultaneously.

[0024] S3. Measure the three output capacitance values ​​C1, C2, and C3 of the three detection units through the measurement circuit;

[0025] S4. Calculate the changes in the three output capacitor values ​​C1, C2, and C3 from their initial values;

[0026] S5. Based on the reading changes and time response curves of the three detection units, determine the abrasive content at different heights in the oil circuit, thereby obtaining the concentration distribution of abrasive particles on the cross-section of the oil circuit.

[0027] S6. Measure the three output impedance values ​​Z1, Z2, and Z3 of the three detection units through the measurement circuit, and calculate the changes of the three output impedance values ​​Z1, Z2, and Z3 from the initial values ​​to supplement and determine the results of the capacitance measurement.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. In this invention, a large number of through holes are set on the electrode plates, allowing the fluid to be measured to flow through the holes and sequentially through each electrode plate. Therefore, the flow direction of the fluid is perpendicular to the surface of the electrode plates, allowing it to quickly pass through the small-pitched planar capacitive sensor. Reducing the spacing between the electrode plates can greatly improve the sensor's measurement sensitivity.

[0030] 2. In this invention, by changing the number and diameter of through holes on the capacitor electrode plate, the fluid pressure and flow field distribution in the detection area between the electrode plates can be changed, so that it has different fluid pressure and flow field distribution from the fluid area before and after flowing into the detection area, thereby realizing the differentiation between different components of the fluid to be measured and high-precision measurement.

[0031] 3. In this invention, due to the large amount of axial offset in the through holes on the two electrode plates of the capacitive sensor, the electric field between the electrode plates is no longer a continuous uniform electric field, but a non-parallel electric field with a large number of edge effects. When the measured fluid with polar components passes through the through holes of the electrode plates, the polar components will change the electric field distribution between the electrode plates, greatly reducing the non-parallel electric field with edge effects, thereby greatly improving the measurement sensitivity of the sensor.

[0032] In summary, the vertical flow capacitive sensor used in this invention can be designed with electrode plates of different through-hole diameters to form a capacitive sensor array, simultaneously measuring different parameters of the fluid or measuring the distribution of fluid parameters in a pipe, which is something that existing technologies cannot achieve. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of a vertical flow capacitance detection device proposed in this invention;

[0034] Figure 2 This is a schematic diagram of the structure of the mesh detection unit composed of metal warp and weft threads proposed in this invention;

[0035] Figure 3 This is a schematic diagram of the nested cylindrical cup electrode unit proposed in this invention;

[0036] Figure 4 This is a schematic diagram of the structure of the three-electrode plate detection unit proposed in this invention;

[0037] Figure 5 This is a schematic diagram of the structure of the serial array detection device proposed in this invention;

[0038] Figure 6 This is a schematic diagram of the parallel array detection device proposed in this invention. Detailed Implementation

[0039] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0040] Example 1:

[0041] Reference Figure 1A vertical flow capacitance detection device includes a fluid to be measured, a detection unit, an outer frame 300, and a measurement circuit 400. The outer frame 300 is a tubular structure made of insulating polymer material. The detection unit 110 is installed inside the outer frame 300, and its left and right ends are connected to an external fluid circuit through pipe joints. The detection unit 110 consists of an electrode unit 100 and an inner frame 200. The inner frame 200 is a tubular structure made of insulating material with a circular boss inside. The electrode unit 100 consists of two parallel electrode plates 101, which are installed on the boss inside the inner frame 200. The distance between the two electrode plates 101 is t. Here, the electrode plates 101 are circular planar metal plates. The electrode plates 101 are provided with a large number of uniformly distributed through holes, which are formed by laser drilling or perforation. The two electrode plates 101 are formed in a manner that the number and diameter of the through holes are different. In this embodiment, the average diameter of the through holes on the left electrode plate is d1, and the average diameter of the through holes on the right electrode plate is d2, where d1>d2. The flow direction of the fluid to be tested in the detection unit 110 is shown by the arrow, passing through each electrode plate 101 sequentially from left to right through the through holes on the electrode plates 101. In this embodiment, the diameter of the through holes on the left electrode plate is larger, and the fluid to be tested flows into the detection area between the electrode plates through the through holes on the left electrode plate. Since the diameter of the through holes on the right electrode plate is smaller, the fluid to be tested in the detection area has different fluid pressure and flow field distribution compared with the fluid in the area before and after flowing into the detection area. Therefore, it is possible to distinguish between different components of the fluid to be tested and to measure them with high precision.

[0042] In this embodiment, the spacing t between the electrode plates 101 can be set very small to increase the sensitivity of the sensor measurement. However, the electrode plate spacing t satisfies the following relationship with the average through-hole diameter d1 on the first electrode plate and the average through-hole diameter d2 on the second electrode plate:

[0043] t <= 10 * d1 + d2.

[0044] The electrode plate 101 can also be configured as a curved shape, such as a bowl shape, a cup shape, etc. The through holes on the electrode plate 101 can also be formed by a metal mesh made of metal wire or a sintered metal filter.

[0045] Example 2:

[0046] Reference Figure 2The electrode is constructed by interlacing or bonding metal warp threads 102 and metal weft threads 103. The surfaces of the metal warp threads 102 and metal weft threads 103 are coated with an insulating layer 104. The metal warp threads 102 and metal weft threads 103 are electrically connected to metal leads 105. The two metal leads 105 are electrically connected to the measuring circuit 400. The measuring circuit 400 can measure the capacitance and impedance of the detection unit 110 through the two metal leads 105. In this embodiment, the through hole is rectangular in shape. Its greatest advantage is that it can greatly reduce the obstruction of fluid flow by the through hole on the electrode. At the same time, since the electric field distribution between the warp and weft threads is a non-parallel electric field, it can greatly improve the detection sensitivity of polar components in polar fluids.

[0047] Example 3:

[0048] Reference Figure 3 The electrode unit 100 is configured to consist of a first cylindrical metal cup 106 and a second cylindrical metal cup 107 nested together. The first cylindrical metal cup 106, located on the outer side, is connected to the negative terminal or ground of the measuring circuit 400, and the second cylindrical metal cup 107, located on the inner side, is connected to the positive terminal of the measuring circuit 400. The first cylindrical metal cup 106 and the second cylindrical metal cup 107 together form the electrode unit 100. The fluid to be measured flows in from below the inner frame 200, then flows sequentially through the second cylindrical metal cup 107 and the first cylindrical metal cup 106, and flows out from the top of the outer frame 300. The advantage of the nested metal cup design is that the first cylindrical metal cup 106 has a good shielding effect, which greatly improves the stability and reliability of the detection device.

[0049] Example 4:

[0050] Reference Figure 4 The electrode unit 100 is configured to consist of three parallel electrode plates 101, which are fixed to the inner frame 200 by a pressure ring 201. The middle electrode plate 101 is connected to the positive terminal of the measurement circuit 400, while the electrode plates 101 on both sides are connected to the negative terminal or ground of the measurement circuit 400. The fluid to be measured enters from the left side of the inner frame 200 and flows through the three electrode plates 101 in sequence. The measurement circuit 400 can measure the capacitance and impedance between two adjacent electrode plates 101 respectively. The design of this embodiment can increase the detection sensitivity and enhance the anti-interference ability.

[0051] Example 5:

[0052] Reference Figure 5The outer frame 300 is provided with a fluid channel 301, and multiple detection units 110 are installed sequentially in the fluid channel 301. Here, the number of detection units is three, forming a series detection array. The diameter of the through hole of the electrode plate 101 of the detection unit 110 gradually decreases with the direction of fluid flow. The fluid to be tested flows in from the left side of the outer frame 300 and then flows through the three detection units 110 in sequence. Since the diameter of the through hole of the electrode plate 101 of the detection unit 110 gradually decreases with the direction of fluid flow, the fluid to be tested in the detection area of ​​the detection unit 110 has different fluid pressure and flow field distribution from the fluid in the areas before and after flowing into the detection area. Therefore, it is possible to achieve the step distinction between different components of the fluid to be tested and high-precision measurement.

[0053] Example 6:

[0054] Reference Figure 6 The outer frame 300 is provided with multiple fluid channels 301, each containing a detection unit 110. The electrode plates 101 on the detection units 110 located in different fluid channels 301 have the same or different through-hole diameters, forming a parallel detection array. The fluid to be tested flows in from the left side of the outer frame 300, is split, and simultaneously flows through three detection units 110. Because the electrode plates 101 on the detection units 110 in different fluid channels 301 have the same or different through-hole diameters, the detection device can simultaneously measure fluid parameters at different locations within the fluid channels. For example, solid particles in the fluid are usually located in the lower part of the pipe; therefore, this detection device can measure the different distributions of abrasive particles along the height direction in the pipe.

[0055] A method of using a vertical flow capacitance detection device includes the following steps:

[0056] S1. A fluid channel 301 is provided on the outer frame 300. Three detection units 110 are arranged in sequence in the fluid channel 301. The average through hole diameters of the two electrode plates 101 in the first detection unit 110 are 0.5 mm and 0.2 mm, respectively. The average through hole diameters of the electrode plates 101 in the second detection unit 110 are 0.2 mm and 0.1 mm, respectively. The average through hole diameters of the electrode plates 101 in the third detection unit 110 are 0.1 mm and 0.07 mm, respectively.

[0057] S2. All detection units 110 are installed such that the direction of the through-hole diameter from large to small is consistent with the direction of fluid flow.

[0058] S3. Install the outer frame 300 in the gas channel to be tested, and measure the three output capacitance values ​​C1, C2, and C3 of the three detection units 110 through the measuring circuit 400.

[0059] S4. Calculate the changes in the three output capacitor values ​​C1, C2, and C3 from their initial values;

[0060] S5. Based on the changes in readings and time response curves of the three detection units 110, determine the concentrations of three solid pollutants in the air with particle sizes of 0.2-0.5 mm, 0.1-0.2 mm, and 0.07-0.1 mm, respectively;

[0061] S6. Measure the three output impedance values ​​Z1, Z2, and Z3 of the three detection units 110 through the measurement circuit 400, calculate the changes in the three output impedance values ​​Z1, Z2, and Z3 compared to the initial values, calculate the ratio of the capacitance change to the impedance change, and determine the polarity and conductivity of the solid pollutant.

[0062] A method of using a vertical flow capacitance detection device includes the following steps:

[0063] S1. Three fluid channels 301 are evenly arranged at the bottom, middle and top of the outer frame 300, and detection units 110 with the same through hole diameter are installed in each channel. The average through hole diameter of the first electrode plate 101 in the detection unit 110 is 0.2 mm, and the average through hole diameter of the second electrode plate 101 in the detection unit 110 is 0.1 mm.

[0064] S2. Insert the outer frame 300 into the oil delivery pipeline so that the oil to be tested flows through three fluid channels 301 at the same time.

[0065] S3. The three output capacitance values ​​C1, C2, and C3 of the three detection units 110 are measured by the measurement circuit 400.

[0066] S4. Calculate the changes in the three output capacitor values ​​C1, C2, and C3 from their initial values;

[0067] S5. Based on the reading changes and time response curves of the three detection units 110, determine the abrasive content at different height positions in the oil circuit, thereby obtaining the concentration distribution of abrasive particles on the cross section of the oil circuit.

[0068] S6. The three output impedance values ​​Z1, Z2, and Z3 of the three detection units 110 are measured by the measurement circuit 400. The changes of the three output impedance values ​​Z1, Z2, and Z3 from the initial values ​​are calculated to supplement and determine the results of the capacitance measurement.

[0069] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A vertical flow capacitance detection device, comprising a fluid to be detected, a detection unit (110), an exoskeleton (300) and a measurement circuit (400), characterized in that, The outer skeleton (300) is internally provided with a detection unit (110), which is composed of an electrode unit (100) and an inner skeleton (200), the electrode unit (100) is installed on the inner skeleton (200), the electrode unit (100) is composed of a plurality of parallel arranged electrode plates (101), a plurality of through holes are arranged on the electrode plate (101), the fluid to be measured flows through the through holes on the electrode plate (101) and passes through each electrode plate (101) in turn, by changing the number and diameter of the through holes on different electrode plates (101), the detection area between the electrode plates (101) and the area before and after the flow into the detection area have different fluid pressure and flow field distribution, so as to realize the differentiation and high precision measurement between different components of the fluid to be measured.

2. The vertical flow capacitive sensing device of claim 1, wherein, The electrode plate (101) is in the shape of a plane or a curved surface, and is formed by punching a metal plate or a metal mesh made of metal wires or a sintered metal filter.

3. The vertical flow capacitive sensing device of claim 1, wherein, The electrode plate (101) is composed of metal warp threads (102) and metal weft threads (103) which are interwoven or bonded, the surfaces of the metal warp threads (102) and the metal weft threads (103) are coated with an insulating layer (104), and the metal warp threads (102) and the metal weft threads (103) are respectively electrically connected with metal lead wires (105), and the two metal lead wires (105) are respectively electrically connected with a measurement circuit (400).

4. The vertical flow capacitive sensing device of claim 1, wherein, The spacing t between the electrode plates (101) and the average through hole diameter d1 on the first electrode plate and the average through hole diameter d2 on the second electrode plate satisfy the following relationship: t<=10*(d1+d2).

5. A vertical flow capacitance detection device according to any one of claims 1-4, characterized in that, The electrode unit (100) is composed of a first cylindrical metal cup (106) and a second cylindrical metal cup (107) nested together, the first cylindrical metal cup (106) on the outside is connected with the negative electrode or the ground of the measurement circuit (400), and the second cylindrical metal cup (107) on the inside is connected with the positive electrode of the measurement circuit (400).

6. A vertical flow capacitance detection device according to any one of claims 1-4, wherein The electrode unit (100) is composed of three parallel arranged electrode plates (101), the electrode plate (101) in the middle is connected with the positive electrode of the measurement circuit (400), and the electrode plates (101) on both sides are connected with the negative electrode or the ground of the measurement circuit (400).

7. A vertical flow capacitive sensing device according to claim 6, wherein, A fluid channel (301) is arranged on the outer skeleton (300), a plurality of detection units (110) are sequentially arranged in the fluid channel (301), and the through hole diameter of the electrode plate (101) of the detection unit (110) gradually decreases along the fluid flow direction.

8. The device of claim 6, wherein the device is a vertical flow capacitive sensing device. A plurality of fluid channels (301) are arranged on the outer skeleton (300), and a detection unit (110) is arranged in each fluid channel (301), and the electrode plates (101) of the detection units (110) arranged in different fluid channels (301) have the same or different through hole diameters.

9. A method of using a vertical flow capacitive sensing device according to claim 7, characterized in that, The method comprises the following steps: S1, a fluid channel (301) is arranged on the exoskeleton (300), and three detection units (110) are arranged in the fluid channel (301) in sequence. The average hole diameters of the two electrode plates (101) in the first detection unit (110) are 0.5 mm and 0.2 mm respectively, the average hole diameters of the electrode plates (101) in the second detection unit (110) are 0.2 mm and 0.1 mm respectively, and the average hole diameters of the electrode plates (101) in the third detection unit (110) are 0.1 mm and 0.07 mm respectively; S2, the installation of all the detection units (110) is such that the direction from large to small of the hole diameters is consistent with the fluid flow direction; S3, the exoskeleton (300) is installed in a gas channel to be measured, and three output capacitance values C1, C2 and C3 of the three detection units (110) are measured by a measurement circuit (400); S4, the change amounts of the three output capacitance values C1, C2 and C3 from initial values are calculated; S5, the concentrations of solid pollutants with three particle sizes of 0.2-0.5 mm, 0.1-0.2 mm and 0.07-0.1 mm in the air are determined according to the reading change amounts and time response curves of the three detection units (110); S6, three output impedance values Z1, Z2 and Z3 of the three detection units (110) are measured by the measurement circuit (400), the change amounts of the three output impedance values Z1, Z2 and Z3 from initial values are calculated, the ratio of the capacitance change amount to the impedance change amount is calculated, and the polarity and conductivity of the solid pollutants are determined.

10. A method of using a vertical flow capacitive sensing device according to claim 8, characterized in that, The method comprises the following steps: S1, three fluid channels (301) are uniformly arranged at the bottom, middle and upper parts of the exoskeleton (300), and detection units (110) with the same hole diameters are installed respectively. The average hole diameter of the first electrode plate (101) in the detection unit (110) is 0.2 mm, and the average hole diameter of the second electrode plate (101) in the detection unit (110) is 0.1 mm; S2, the exoskeleton (300) is installed in an oil conveying pipeline, so that the oil to be measured flows through the three fluid channels (301) simultaneously; S3, three output capacitance values C1, C2 and C3 of the three detection units (110) are measured by a measurement circuit (400); S4, the change amounts of the three output capacitance values C1, C2 and C3 from initial values are calculated; S5, the abrasive particle content at different height positions in the oil circuit is determined according to the reading change amounts and time response curves of the three detection units (110), so that the concentration distribution of the abrasive particles on the oil circuit section is obtained; S6, three output impedance values Z1, Z2 and Z3 of the three detection units (110) are measured by the measurement circuit (400), the change amounts of the three output impedance values Z1, Z2 and Z3 from initial values are calculated, and the results of the capacitance measurement are supplemented and determined.

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