CN110794164A - System and method for measuring high space-time precision of liquid metal velocity field under strong magnetic field - Google Patents
System and method for measuring high space-time precision of liquid metal velocity field under strong magnetic field Download PDFInfo
- Publication number
- CN110794164A CN110794164A CN201911279604.3A CN201911279604A CN110794164A CN 110794164 A CN110794164 A CN 110794164A CN 201911279604 A CN201911279604 A CN 201911279604A CN 110794164 A CN110794164 A CN 110794164A
- Authority
- CN
- China
- Prior art keywords
- probe
- wall surface
- liquid metal
- magnetic field
- velocity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910001338 liquidmetal Inorganic materials 0.000 title claims abstract description 43
- 238000000034 method Methods 0.000 title claims description 34
- 239000000523 sample Substances 0.000 claims abstract description 110
- 238000007654 immersion Methods 0.000 claims abstract description 50
- 230000001360 synchronised effect Effects 0.000 claims abstract description 13
- 238000006073 displacement reaction Methods 0.000 claims abstract description 9
- 239000012530 fluid Substances 0.000 claims description 19
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 16
- 229910052802 copper Inorganic materials 0.000 claims description 15
- 239000010949 copper Substances 0.000 claims description 15
- 239000007788 liquid Substances 0.000 claims description 11
- 238000003491 array Methods 0.000 claims description 10
- 238000005070 sampling Methods 0.000 claims description 7
- 239000003292 glue Substances 0.000 claims description 6
- 230000002596 correlated effect Effects 0.000 claims description 4
- 238000007405 data analysis Methods 0.000 claims description 4
- 230000000875 corresponding effect Effects 0.000 claims description 3
- 238000009826 distribution Methods 0.000 claims description 3
- 230000004907 flux Effects 0.000 claims description 3
- 229910001220 stainless steel Inorganic materials 0.000 claims description 3
- 239000010935 stainless steel Substances 0.000 claims description 3
- 238000000926 separation method Methods 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 claims 1
- 238000000576 coating method Methods 0.000 claims 1
- 238000005259 measurement Methods 0.000 abstract description 22
- 230000000694 effects Effects 0.000 abstract description 3
- 238000003672 processing method Methods 0.000 abstract 1
- 238000011160 research Methods 0.000 description 6
- 238000004458 analytical method Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000003384 imaging method Methods 0.000 description 3
- 230000005514 two-phase flow Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000005253 cladding Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 230000002123 temporal effect Effects 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 238000009530 blood pressure measurement Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000009851 ferrous metallurgy Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000010297 mechanical methods and process Methods 0.000 description 1
- 239000000693 micelle Substances 0.000 description 1
- 239000012811 non-conductive material Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000010349 pulsation Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 239000000565 sealant Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 238000002604 ultrasonography Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
- G01P5/08—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring variation of an electric variable directly affected by the flow, e.g. by using dynamo-electric effect
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M10/00—Hydrodynamic testing; Arrangements in or on ship-testing tanks or water tunnels
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Aviation & Aerospace Engineering (AREA)
- Fluid Mechanics (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
The measuring system comprises a microprobe array and a concentrator thereof, an immersion probe and a three-dimensional displacement device thereof, and a multi-channel high-precision synchronous voltage acquisition system, wherein the microprobe array and the concentrator thereof are integrated on the wall surface of a channel; the position of the immersion probe is automatically controlled by a computer through a displacement device of the immersion probe; signals of the wall surface microneedle array and the immersion probe are connected into a synchronous voltage acquisition system; the system is used for realizing accurate measurement of the liquid metal velocity field; taking pipeline flow as an example, a testing step and a data processing method are given; the probe structure in various forms is used for measuring the multipoint local velocity component, and the velocity field information such as the near wall surface velocity, the main flow vorticity and the like can also be measured; the invention overcomes the difficulty that the liquid metal velocity field is difficult to measure, and has the characteristics of strong practicability and good measuring effect.
Description
Technical Field
The invention belongs to the technical field of fluid measurement, and particularly relates to a high-space-time-precision measurement system and method for a liquid metal velocity field in a strong magnetic field.
Background
The liquid metal flow phenomenon can be understood as the combination of electromagnetic and hydrodynamic properties, has rich fundamental research significance, and also has important engineering application scenes in the ferrous metallurgy industry and the magnetic confinement fusion reactor. In particular, fusion reactors involve physical and engineering problems with the flow heat transfer of large quantities of liquid metal. Due to the characteristics of cross-scale, multi-field coupling, light tightness and high temperature of the liquid metal flow, a plurality of traditional measurement means cannot be suitable, and the research is very challenging. From the history of development of magnetohydrodynamics, the liquid metal flow field measurement technology is important to the development of disciplines.
According to literature research, the existing liquid metal local flow field measurement scheme is summarized as follows:
1. potential probe method. It measures the potential difference perpendicular to the direction of the magnetic field generated by the fluid in a constant magnetic field. The probe is immersed in the liquid and must maintain good electrical contact therewith. The advantage is that the time resolution is high, the probe and the space can be designed to be very small to measure the local speed, and the development into an array is facilitated to obtain rich transient flow field information.
2. The permanent magnet probe method is to closely attach the tiny permanent magnet and the potential probe and immerse the tiny permanent magnet and the potential probe into fluid. The principle is similar to the potentiometric probe method, but is only applicable to flow rate measurements without a background magnetic field.
3. The resistance probe method is commonly used for measuring the two-phase flow of the liquid metal. The principle is that the resistance measured when the liquid phase passes through the probe region drops significantly, while the resistance rises sharply when the gas phase passes. This solution necessitates careful adjustment of the electrical contact properties of the probe with the liquid.
4. Hot wire anemometers are the same technology as traditional hot wire anemometers. Based on the heat exchange between the resistance wire and the flow field in the heating state, the temperature of the resistance wire is linearly related to the flow velocity of the peripheral liquid.
5. Pressure measurement (pitot tube) is a conventional immersion measurement scheme used in liquid metal for measurement of the main flow velocity.
6. Precision opto-mechanical methods are based on the mechanical force of a fluid on an immersed microscopic probe. The requirement on the mounting accuracy is high.
7. The pulse ultrasonic velocity measurement method and the branch thereof are widely applied to the measurement of liquid metal. The probe sends a unidirectional ultrasonic pulse into the fluid and receives signals that are progressively reflected by fluid micelles at different distances. The space position of the fluid micro-cluster is calculated through the time difference of sending and receiving, and the velocity of the fluid micro-cluster is calculated through the Doppler frequency shift of sending and receiving, so that the signal can calculate the one-dimensional flow field information of the ultrasonic wave transmitting direction. In the pulse ultrasonic method, the probe can be installed on the wall surface without being immersed in liquid, and has no influence on the flow field.
8. The high-energy ray imaging is mainly used for researching liquid metal two-phase flow. The application of gamma rays, X rays and neutron rays in the measurement of the liquid metal flow field is already known in the literature. Abundant two-dimensional flow field information can be analyzed from the image. The limitation is however that the radiation is attenuated very rapidly in the fluid, and its measurement depth in the direction of the radiation is usually only in the order of centimeters. On the other hand, increasing its temporal resolution, or improving it into a three-dimensional measurement system, still faces a number of technical challenges.
9. Some local flow field measurement methods based on secondary induced magnetic fields. Such as electromagnetic imaging (imaging techniques based on resistance, conductance or capacitance measurements), induction coil methods. Such methods are based on induced magnetic field feedback of the fluid under an external alternating (or constant) magnetic field. Flow field information is derived in reverse based on the magnetic field signals.
10. A lorentz force velocimeter is also a method based on an induced magnetic field. It measures the reaction force of the induced magnetic field generated by the fluid against the magnetic source (i.e., the permanent magnet). Its spatial resolution is limited to the size of the permanent magnet (down to the millimeter level) and its temporal resolution is limited to the mechanical structural properties of the sensor.
In conclusion, method 2 is not suitable for a strong background magnetic field environment; methods 3, 8 are primarily for two-phase flow; method 4 is not applicable in hot environments; method 5 is used for mainstream measurement, and local velocity is difficult to measure; method 6 is insufficient in time resolution; method 7 remains a spatial averaging method on the ultrasound scale; the signals of the methods 9 and 10 both depend on the integral effect of the electromagnetic action on the local space, and the spatial resolution is deficient.
Disclosure of Invention
In order to make up for the defects of the prior art, the invention aims to provide a system and a method for measuring the high space-time precision of a liquid metal velocity field in a strong magnetic field.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the high-space-time precision measuring system of the liquid metal velocity field under the strong magnetic field comprises a wall surface detector 3, an immersion probe 4 is arranged in a main flow area of a channel, the immersion probe 4 is fixed on a displacement device 5, and signal ends of the wall surface detector 3 and the immersion probe 4 are connected to a multi-channel high-precision synchronous voltage acquisition system 6.
The immersion probes 4 are spaced by 1-5mm in pairs, are single immersion probes and comprise a plurality of copper wires with insulating layers, the diameter of each copper wire is 0.1-0.5mm, the copper wires penetrate into a hollow copper pipe body or a stainless steel pipe body with the diameter of 2-5mm after being bound, the copper wires exceed the pipe body by 10-30mm, glue is filled and fixed in the pipe body, the insulating layers are coated on the whole pipe body, the fact that the probe is not in electric contact with liquid after being immersed is guaranteed, and only the tips of the copper wires are in electric contact with the liquid metal.
The wall surface detector 3 comprises a micro probe array 3-1, the distance between arrays is 1-5mm, one end of the micro probe array 3-1 is inserted into a wall surface micropore reserved on the wall surface of a channel and penetrates through the wall surface of the channel to be vertically welded on a circuit board 3-2, the micro probe array 3-1 is entirely covered with an insulating cladding, and only the probe tip at the other end of the micro probe array 3-1 keeps electric contact with fluid; the wall surface micropores are filled with insulating glue, so that liquid is prevented from leaking, and the probes are matched with a prefabricated circuit on the wall surface electric insulation circuit board 3-2 to form voltage signal positive and negative electrodes to form a line concentration plug 3-3.
The multi-channel high-precision synchronous voltage acquisition system 6 is connected with the wall surface detector 3 and the immersion probe 4 through a shielding signal line, and acquires and stores voltage signals; the synchronous acquisition capacity of 200 channels or more of analog signals is provided; acquisition speeds of 500S/S or more can be achieved.
The method of the measuring system of the high space-time precision of the liquid metal velocity field under the strong magnetic field comprises the following steps:
firstly, an immersion probe 4 measures a voltage signal which is proportional to the flow velocity, and based on the basic principle of ohm's law, the flow of liquid metal in a magnetic field generates an induced potential difference perpendicular to the flow direction:
where j is the current density, σ is the liquid metal conductivity,the signal is measured as the potential difference, u is the flow velocity, B is the magnetic flux density, under the external strong magnetic field, j/sigma-0, therefore the potential difference between two measuring points is directly related to the velocity, and the fluid velocity is:
where dz is the separation of two points of the potential probe in a direction perpendicular to the magnetic field and the flow plane. The immersion probe 4 is fixed on the displacement device 5, the immersion probe 4 can measure the local speed of each position by displacing to each position on the flow section, the data analysis method of the immersion probe 4 comprises the corresponding relation of the potential difference and the speed component in different directions of the same position, the three-dimensional speed information of the same position in space is reflected, and according to ohm's law, two speed components perpendicular to the direction of the magnetic field 2 are positively correlated with the potential thereof, namely ux～dφ7,8＝φ7-φ8，uz～dφ9,10＝φ9-φ10；
The principle of the wall surface detector 3 is consistent with that of the immersion probe 4, the wall surface detector 3 integrates an array formed by a plurality of micro-needles, a group of voltage signals are formed between every two adjacent micro-needles of the array, and the voltage signals correspond to a local flow velocity, so that the wall surface detector 3 can measure the speed of multiple points to form a speed distribution result;
thirdly, determining the probe spacing, selecting the probe spacing, wherein the distance between every two immersion probes 4 and the distance between the microprobe arrays 3-1 are 1-5 mm;
fourthly, determining a sampling speed, wherein the sampling speed is higher than 500S/S;
and fifthly, the signals of the wall surface detector 3 and the immersion probe 4 are jointly analyzed, and the correlation of local velocities at different spatial positions reflects the whole flow structure.
Compared with the prior art, the invention has the following advantages:
1. the method is suitable for opaque liquid metal measurement, and compared with other liquid metal measurement means, the local velocity field measured by the method is finer, and the method has excellent time (millisecond level) and space (less than millimeter level) resolution.
2. The probe is thin, the response is fast, and the manufacturing cost is low; the effect on the flow is negligible. The high-temperature-resistant and high-intensity magnetic field sensor can bear high temperature and high magnetic field environment, is not sensitive to fluid conductivity, and has good vibration resistance.
3. The invention has the characteristic of easy expansion, and can arrange a large number of probe measuring points according to the requirement to obtain clear whole field data in a large space range.
Drawings
Fig. 1 illustrates an implementation method of the measurement system by taking a pipeline flow as an example.
FIG. 2 is a schematic diagram of a structure of an immersion probe.
FIG. 3 is a schematic diagram of a micro probe array and a circuit board thereof.
FIG. 4 is a schematic view of the wall mount of the probe array.
Fig. 5 is a signal processing flow.
Detailed Description
The invention relates to a method for measuring a local flow field of liquid metal, which is mainly used for measuring the potential difference formed between microprobes by the flow field. The main measuring components comprise a microprobe array and a concentrator thereof, an immersion probe and a three-dimensional displacement device thereof, and a multi-channel high-precision synchronous voltage acquisition system, which are integrated on the wall surface of a channel.
The following takes the pipe flow of the liquid metal under the background magnetic field as an example, and further describes the pipe flow with reference to the attached drawings.
As shown in fig. 1, a liquid metal main flow velocity 1, an external magnetic field 2, and a main flow velocity 1 are provided by an external circulation loop system. The external magnetic field 2 may come from a permanent magnet, an electromagnet or a superconducting magnet, providing a stable magnetic field environment for the pipe. The system for measuring the high space-time precision of the liquid metal velocity field under the strong magnetic field comprises a plurality of wall surface detectors 3, and can measure the flow field information close to the wall surface. An immersion probe 4 is arranged in the main flow area of the channel, the immersion probe 4 is fixed on a displacement device 5, and the immersion probe 4 can measure the local speed of each position by displacing to each position on the flow section. The signal ends of the wall surface detector 3 and the immersion probe 4 are connected to a multi-channel high-precision synchronous voltage acquisition system 6, and are used for acquiring and storing potential data and converting the potential data into speed field information.
As shown in fig. 2, the immersion probes 4 are spaced 1-5mm apart from each other, are single immersion probes, and include a plurality of copper wires with insulating layers, the diameter of which is 0.1-0.5mm, the copper wires penetrate into the hollow copper tube body or the stainless steel tube body with the diameter of 2-5mm after being bound, the copper wires exceed the tube body by 10-30mm, the tube body is internally filled with glue for fixation, the insulating layers are coated on the whole tube body, it is ensured that the whole probe is not in electrical contact with liquid after being immersed, and only the tips of the copper wires keep electrical contact with the liquid metal.
As shown in fig. 3, the wall surface detector 3 includes a micro probe array 3-1, the distance between arrays is 1-5mm, one end of the micro probe array 3-1 is inserted into a wall surface micropore reserved on the wall surface of a channel and penetrates through the wall surface of the channel to be vertically welded on a circuit board 3-2, the micro probe array 3-1 is entirely covered with an insulating cladding, and only the probe tip at the other end of the micro probe array 3-1 keeps electrical contact with a liquid fluid; the wall surface micropores are filled with insulating glue, so that liquid is prevented from leaking, and the probe is electrically insulated from the wall surface. The circuit board 3-2 is provided with a prefabricated circuit, and the probes are matched to form a voltage signal anode and a voltage signal cathode to form a line concentration plug 3-3. The multi-channel high-precision synchronous voltage acquisition system 6 is connected with the wall surface detector 3 and the immersion probe 4 through a shielding signal line, and acquires and stores voltage signals; the synchronous acquisition capacity of 200 channels or more of analog signals is provided; the high-voltage-resolution high-precision grounding device has high voltage resolution, the precision reaches microvolt level, and meanwhile, the high-voltage-resolution high-precision grounding device has a good grounding design and reduces signal noise generated by electromagnetic interference. The multi-channel high-precision synchronous voltage acquisition system 6 can achieve the acquisition speed of 500S/S or higher.
A plurality of probe arrays are transversely and longitudinally arranged on the wall surface perpendicular to the direction of the magnetic field, the tips of the probes can be tightly attached to the inner wall of the pipeline or exceed the inner wall by 1-5mm, and two-dimensional velocity field information of the wall surface close to the wall surface and parallel to the wall surface can be obtained based on the same principle as the immersion probe. The method is also suitable for the wall surface of a conductive or non-conductive material. When the wall surface is made of conductive material, the gap between the probe and the wall surface should be filled with insulating material to block the electrical contact between the probe and the wall surface, as shown in fig. 4, 13 to 16 are wall surface probes, and 17 is an insulating sealant filled between the probe and the micropore.
The method of the measuring system of the high space-time precision of the liquid metal velocity field under the strong magnetic field comprises the following steps:
firstly, an immersion probe 4 measures a voltage signal which is proportional to the flow velocity, and based on the basic principle of ohm's law, the flow of liquid metal in a magnetic field generates an induced potential difference perpendicular to the flow direction:
where j is the current density, σ is the liquid metal conductivity,
the signal is measured as the potential difference, u is the flow velocity, B is the magnetic flux density, under the external strong magnetic field, j/sigma-0, therefore the potential difference between two measuring points is directly related to the velocity, and the fluid velocity is:
wherein dz is the potential of the probe at two points perpendicular to the magnetic field and flowPitch in the planar direction. Since the immersion probe 4 is fixed to the displacement device 5, the immersion probe 4 can measure the local velocity at each position by displacing to each position on the flow cross section. Specifically, as shown in FIG. 2, the data analysis method for the immersion probe 4 includes the corresponding relationship between the potential difference and the velocity component in different directions at the same position, reflecting the three-dimensional velocity information at the same position in space, and according to ohm's law, two velocity components perpendicular to the direction of the magnetic field 2 are positively correlated with the potential thereof, i.e. ux～dφ7,8＝φ7-φ8，uz～dφ9,10＝φ9-φ10。
Secondly, the wall detector 3 is constructed as shown in FIG. 3, and its basic principle is consistent with the immersion probe 4. The difference lies in that the immersion probe 4 only collects the flow velocity of a single space point, and the wall surface detector 3 integrates an array formed by a plurality of micro-needles, and a group of voltage signals are formed between every two adjacent micro-needles of the array, and correspond to a local flow velocity, so that the wall surface detector 3 can measure the multi-point velocity to form a velocity distribution result.
And thirdly, determining the probe distance. Regarding the choice of probe pitch. The distance between every two immersion probes 4 and the distance between every two micro probe arrays 3-1 are close to each other as much as possible when the probes are manufactured, namely delta l is as small as possible. The smaller Δ l, the lower the signal amplitude, and the smaller the signal-to-noise ratio with respect to the ambient noise, the less easily it is measured. As can be seen from the above analysis, the choice of Δ l is always a trade-off for different research objectives. For the measurement of the local velocity of the liquid metal fluid, the range of the measurement signal d phi is about 40 to 4000 microvolts, for example Δ l is 4mm, u is 0.1 to 1m/s, and B is 0.1 to 1T. For liquid metal flow measurements, the invention proposes Δ l to be between 1 and 5 mm.
And fourthly, determining the sampling speed. From the above, the velocity directly measured by the probe is actually the spatial average flow field information on the spatial Δ l scale. In some cases this spatial resolution is not sufficient. Under the condition of stable turbulence, if the sampling speed is high enough, the pulse speed high-frequency information can be obtained by carrying out frequency domain analysis on the pulse speed time sequence signal, and the pulse speed high-frequency information corresponds to the speed pulse with smaller space scale, namely
d phi 'u', u '(high frequency) u' (small spatial dimension)
According to the turbulence structure theory, the frequency domain analysis result corresponds to the flow space scale one by one. The method can establish the relation between the time scale and the space scale of the local speed signal and can obtain the local speed pulsation information under the extremely small space scale. For liquid metal flow measurements, the present invention suggests a sampling speed higher than 500S/S.
And fifthly, jointly analyzing signals of the wall surface detector 3 and the immersion probe 4. The correlation of local velocities at different spatial locations reflects the overall flow structure. The data analysis flow is shown in fig. 5. For example, in the case where the external magnetic field 2 is strong, the liquid metal flows to form a quasi-two-dimensional structure. J is measured from the immersion probe 4y0, i.e. d phi11,12＝φ11-φ120, thus d phi11,12Is a quantitative index for the conversion of flowing three-dimensional and two-dimensional structures. On the other hand, the velocity measured by the two side wall surface probe arrays 3 and the probe 4 is highly correlated, which also indicates that the flow forms a quasi-two-dimensional structure. It should be noted that, as the external magnetic field is strengthened, the three-dimensional and two-dimensional transformation of the flow is a gradual process, and the detailed research thereof is not sufficient, and it is the research object of the patent technology.
Claims (5)
1. The high-space-time precision measuring system of the liquid metal velocity field under the strong magnetic field is characterized by comprising a wall surface detector (3), wherein an immersion probe (4) is arranged in a main flow area of a channel, the immersion probe (4) is fixed on a displacement device (5), and signal ends of the wall surface detector (3) and the immersion probe (4) are connected to a multi-channel high-precision synchronous voltage acquisition system (6).
2. The system for measuring the high space-time precision of the liquid metal velocity field under the high magnetic field according to claim 1, wherein the immersion probes (4) are spaced by 1-5mm in pairs, are single immersion probes, and comprise a plurality of copper wires with insulating layers and diameters of 0.1-0.5mm, the copper wires penetrate into a hollow copper tube body or a stainless steel tube body with diameters of 2-5mm after being bound, the copper wires exceed 10-30mm of the tube body, the tube body is fixed by filling glue, the insulating layers are coated on the whole tube body, the fact that the whole probe is not in electric contact with liquid after being immersed is guaranteed, and only the tips of the copper wires are in electric contact with the liquid metal.
3. The system for measuring the high space-time precision of the velocity field of the liquid metal under the strong magnetic field according to claim 1, wherein the wall surface detector (3) comprises micro probe arrays (3-1), the distance between the arrays is 1-5mm, one end of each micro probe array (3-1) is inserted into a wall surface micropore reserved on the wall surface of a channel and penetrates through the wall surface of the channel to be vertically welded on a circuit board (3-2), the micro probe arrays (3-1) are all covered with an insulating coating, and only probe tips at the other end of each micro probe array (3-1) are kept in electrical contact with a fluid; the wall surface micropores are filled with insulating glue, so that liquid is prevented from leaking, and the probe is electrically insulated from the wall surface. The circuit board (3-2) is provided with a prefabricated circuit, and the probes are matched to form a voltage signal positive electrode and a voltage signal negative electrode to form a line concentration plug (3-3).
4. The system for measuring the high space-time precision of the velocity field of the liquid metal in the high magnetic field according to claim 1, wherein the multichannel high-precision synchronous voltage acquisition system (6) is connected with the wall surface detector (3) and the immersion probe (4) through shielded signal lines to acquire and store voltage signals; the synchronous acquisition capacity of 200 channels or more of analog signals is provided; acquisition speeds of 500S/S or more can be achieved.
5. The method for measuring the high space-time precision of the liquid metal velocity field under the strong magnetic field according to any one of the preceding claims, characterized by comprising the following steps:
firstly, an immersion probe (4) measures to obtain a voltage signal which is proportional to flow speed, and based on the basic principle of ohm's law, the liquid metal flowing in a magnetic field can generate an induced potential difference which is vertical to the flowing direction:
where j is the current density, σ is the liquid metal conductivity,
the signal is measured as the potential difference, u is the flow velocity, B is the magnetic flux density, under the external strong magnetic field, j/sigma-0, therefore the potential difference between two measuring points is directly related to the velocity, and the fluid velocity is:
wherein dz is the separation of two points of the potential probe in a direction perpendicular to the magnetic field and the flow plane; the immersion probe (4) is fixed on the displacement device (5), the immersion probe (4) measures the local speed of each position by displacing to each position on the flow section, the data analysis method of the immersion probe (4) comprises the corresponding relation of the potential difference and the speed component in different directions of the same position, the three-dimensional speed information of the same position in space is reflected, and according to ohm's law, two speed components vertical to the direction of the magnetic field (2) are positively correlated with the electric potential thereof, namely u is ux～dφ7,8＝φ7-φ8，uz～dφ9,10＝φ9-φ10；
The principle of the wall surface detector (3) is consistent with that of the immersion probe (4), the wall surface detector (3) integrates an array formed by a plurality of micro-needles, a group of voltage signals are formed between every two adjacent micro-needles of the array, and the local flow velocity corresponds to one group of voltage signals, so that the wall surface detector (3) can measure multipoint velocities to form a velocity distribution result;
thirdly, determining the probe spacing, selecting the probe spacing, wherein the distance between every two immersion probes (4) and the spacing between the microprobe arrays (3-1) are 1-5 mm;
fourthly, determining a sampling speed, wherein the sampling speed is higher than 500S/S;
and fifthly, the signals of the wall surface detector (3) and the immersion probe (4) are jointly analyzed, and the correlation of local speeds at different spatial positions reflects the whole flow structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911279604.3A CN110794164A (en) | 2019-12-13 | 2019-12-13 | System and method for measuring high space-time precision of liquid metal velocity field under strong magnetic field |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911279604.3A CN110794164A (en) | 2019-12-13 | 2019-12-13 | System and method for measuring high space-time precision of liquid metal velocity field under strong magnetic field |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110794164A true CN110794164A (en) | 2020-02-14 |
Family
ID=69448339
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911279604.3A Pending CN110794164A (en) | 2019-12-13 | 2019-12-13 | System and method for measuring high space-time precision of liquid metal velocity field under strong magnetic field |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110794164A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112083185A (en) * | 2020-09-07 | 2020-12-15 | 西安交通大学 | Liquid metal flow velocity measurement experiment system on surface of liquid metal pump blade |
| CN112230013A (en) * | 2020-09-18 | 2021-01-15 | 中国航发哈尔滨东安发动机有限公司 | Method and device for measuring flow velocity of high-temperature conductive fluid |
| CN112665821A (en) * | 2020-12-21 | 2021-04-16 | 西安交通大学 | Device and method for measuring speed and vorticity in conductive fluid under strong magnetic field condition |
| CN112985758A (en) * | 2021-02-04 | 2021-06-18 | 四川大学 | Experimental device and method for measuring vortex size in complex gas-liquid two-phase flow |
| CN113009178A (en) * | 2021-02-18 | 2021-06-22 | 上海交通大学 | Flow velocity measurement system based on sliding electric arc |
| CN113820026A (en) * | 2021-10-15 | 2021-12-21 | 西安交通大学 | Thermocouple combined type speed potential probe and measuring method |
| CN113884136A (en) * | 2021-09-29 | 2022-01-04 | 西安交通大学 | Separated temperature-velocity coupling potential probe and preparation and measurement method thereof |
| CN114088228A (en) * | 2021-11-12 | 2022-02-25 | 中国科学院大学 | Device and method for measuring velocity field and temperature field of metal fluid under strong magnetic field condition |
| CN116275763A (en) * | 2023-05-22 | 2023-06-23 | 中国航发四川燃气涡轮研究院 | Hot wire welding method and device for one-dimensional probe of hot wire anemometer |
| CN117367505A (en) * | 2023-10-12 | 2024-01-09 | 西安交通大学 | Method for measuring internal structural parameters of liquid metal |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4828610A (en) * | 1986-06-16 | 1989-05-09 | Solmecs Corporation N.V. | Method and apparatus for modification of the rate of heat or mass transfer in a stream of liquid metal |
| JPH08247812A (en) * | 1995-03-15 | 1996-09-27 | Toshiba Corp | Electromagnetic flowmeter |
| JPH11201980A (en) * | 1998-01-13 | 1999-07-30 | Nkk Corp | Flow velocity measuring method and device |
| JP2000152600A (en) * | 1998-11-10 | 2000-05-30 | Kazuyuki Ueno | Induction-type electromagnetic drive device for conductive fluid |
| US20060162895A1 (en) * | 2002-11-29 | 2006-07-27 | Abb Ab | Control system, computer program product, device and method |
| CN102654513A (en) * | 2012-03-30 | 2012-09-05 | 中国科学院合肥物质科学研究院 | Method for measuring speed distribution of liquid metal boundary layer under high-temperature strong magnetic field |
| EA201100766A1 (en) * | 2011-04-07 | 2012-10-30 | Зарецкий, Александр Константинович | METHOD OF ELECTRIC POWER SUPPLY OF A RAIL ELECTROMAGNETIC ACCELERATOR, ELECTROMAGNETIC CONSTRUCTION OF RELSOTRON, RAIL JET |
| CN103207211A (en) * | 2013-03-06 | 2013-07-17 | 中国科学院合肥物质科学研究院 | Device and method for measuring liquid metal two-phase flow void fraction |
| CN104458108A (en) * | 2014-12-11 | 2015-03-25 | 中国科学院合肥物质科学研究院 | Method for measuring pressure drop of liquid metal pipe flow magnetic fluid under high-intensity magnetic field |
| CN104733057A (en) * | 2013-12-23 | 2015-06-24 | 核工业西南物理研究院 | Method for controlling magnetofluid instability of liquid metal planar film flow in high-intensity magnetic field |
| CN110007110A (en) * | 2019-04-22 | 2019-07-12 | 中国科学院大学 | Method and device based on electromagnetic induction principle measurement high temperature fluent metal flow velocity |
| CN110426565A (en) * | 2019-08-28 | 2019-11-08 | 上海大学 | Electromagnetic field and flow field physical simulating device and method in a kind of secondary cooling area for continuous casting molten steel |
-
2019
- 2019-12-13 CN CN201911279604.3A patent/CN110794164A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4828610A (en) * | 1986-06-16 | 1989-05-09 | Solmecs Corporation N.V. | Method and apparatus for modification of the rate of heat or mass transfer in a stream of liquid metal |
| JPH08247812A (en) * | 1995-03-15 | 1996-09-27 | Toshiba Corp | Electromagnetic flowmeter |
| JPH11201980A (en) * | 1998-01-13 | 1999-07-30 | Nkk Corp | Flow velocity measuring method and device |
| JP2000152600A (en) * | 1998-11-10 | 2000-05-30 | Kazuyuki Ueno | Induction-type electromagnetic drive device for conductive fluid |
| US20060162895A1 (en) * | 2002-11-29 | 2006-07-27 | Abb Ab | Control system, computer program product, device and method |
| EA201100766A1 (en) * | 2011-04-07 | 2012-10-30 | Зарецкий, Александр Константинович | METHOD OF ELECTRIC POWER SUPPLY OF A RAIL ELECTROMAGNETIC ACCELERATOR, ELECTROMAGNETIC CONSTRUCTION OF RELSOTRON, RAIL JET |
| CN102654513A (en) * | 2012-03-30 | 2012-09-05 | 中国科学院合肥物质科学研究院 | Method for measuring speed distribution of liquid metal boundary layer under high-temperature strong magnetic field |
| CN103207211A (en) * | 2013-03-06 | 2013-07-17 | 中国科学院合肥物质科学研究院 | Device and method for measuring liquid metal two-phase flow void fraction |
| CN104733057A (en) * | 2013-12-23 | 2015-06-24 | 核工业西南物理研究院 | Method for controlling magnetofluid instability of liquid metal planar film flow in high-intensity magnetic field |
| CN104458108A (en) * | 2014-12-11 | 2015-03-25 | 中国科学院合肥物质科学研究院 | Method for measuring pressure drop of liquid metal pipe flow magnetic fluid under high-intensity magnetic field |
| CN110007110A (en) * | 2019-04-22 | 2019-07-12 | 中国科学院大学 | Method and device based on electromagnetic induction principle measurement high temperature fluent metal flow velocity |
| CN110426565A (en) * | 2019-08-28 | 2019-11-08 | 上海大学 | Electromagnetic field and flow field physical simulating device and method in a kind of secondary cooling area for continuous casting molten steel |
Non-Patent Citations (3)
| Title |
|---|
| DANIEL HERNANDEZ: ";Numerical and experimental study on vorticity measurement in liquid mental using local Lorentz force", 《MEASUREMENT SCIENCE AND TECHNOLOGY》, 8 February 2018 (2018-02-08) * |
| TAN YANQING: "Preliminary experimental study on applicability of Lorentz force velocimetry in external magnetic field", 《NUCLEAR SCIENCE AND TECHNIQUES》, 25 April 2018 (2018-04-25) * |
| 张华祥: "电磁场下液态金属流速的测量技术分析", 自动化仪表, 17 January 2018 (2018-01-17) * |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112083185A (en) * | 2020-09-07 | 2020-12-15 | 西安交通大学 | Liquid metal flow velocity measurement experiment system on surface of liquid metal pump blade |
| CN112230013A (en) * | 2020-09-18 | 2021-01-15 | 中国航发哈尔滨东安发动机有限公司 | Method and device for measuring flow velocity of high-temperature conductive fluid |
| CN112665821A (en) * | 2020-12-21 | 2021-04-16 | 西安交通大学 | Device and method for measuring speed and vorticity in conductive fluid under strong magnetic field condition |
| CN112985758A (en) * | 2021-02-04 | 2021-06-18 | 四川大学 | Experimental device and method for measuring vortex size in complex gas-liquid two-phase flow |
| CN113009178A (en) * | 2021-02-18 | 2021-06-22 | 上海交通大学 | Flow velocity measurement system based on sliding electric arc |
| CN113884136A (en) * | 2021-09-29 | 2022-01-04 | 西安交通大学 | Separated temperature-velocity coupling potential probe and preparation and measurement method thereof |
| CN113820026A (en) * | 2021-10-15 | 2021-12-21 | 西安交通大学 | Thermocouple combined type speed potential probe and measuring method |
| CN114088228A (en) * | 2021-11-12 | 2022-02-25 | 中国科学院大学 | Device and method for measuring velocity field and temperature field of metal fluid under strong magnetic field condition |
| CN116275763A (en) * | 2023-05-22 | 2023-06-23 | 中国航发四川燃气涡轮研究院 | Hot wire welding method and device for one-dimensional probe of hot wire anemometer |
| CN116275763B (en) * | 2023-05-22 | 2023-08-18 | 中国航发四川燃气涡轮研究院 | Hot wire welding method and device for one-dimensional probe of hot wire anemometer |
| CN117367505A (en) * | 2023-10-12 | 2024-01-09 | 西安交通大学 | Method for measuring internal structural parameters of liquid metal |
| CN117367505B (en) * | 2023-10-12 | 2024-06-07 | 西安交通大学 | Method for measuring internal structural parameters of liquid metal |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110794164A (en) | System and method for measuring high space-time precision of liquid metal velocity field under strong magnetic field | |
| CN112665821B (en) | Device and method for measuring speed and vorticity in conductive fluid under strong magnetic field condition | |
| CN211348305U (en) | High space-time precision measuring device for liquid metal velocity field under strong magnetic field | |
| CN114088228A (en) | Device and method for measuring velocity field and temperature field of metal fluid under strong magnetic field condition | |
| Bera et al. | Study of a modified capacitance-type level transducer for any type of liquid | |
| Ratajczak et al. | Measurement techniques for liquid metals | |
| JPH05501916A (en) | Electromagnetic flowmeters and related improvements | |
| US5390548A (en) | Electrode array electromagnetic velocimeter | |
| CN102998343A (en) | Two-phase flow tomography system based on array-type monopole conducting probe | |
| Belyaev et al. | Temperature correlation velocimetry technique in liquid metals | |
| Wang et al. | Measurement of liquid film thickness using distributed conductance sensor in multiphase slug flow | |
| CN101609066B (en) | Electromagnetic sensing imaging system based on screen mesh and method thereof | |
| CN113063341B (en) | Device and method for three-dimensional real-time measurement of thickness of annular flow liquid film and interfacial wave | |
| US5426983A (en) | Flow meter | |
| CN113848240A (en) | Gas-liquid two-phase flow section imaging device | |
| JP2010107487A (en) | Device and method for measuring multiphase flow | |
| CN113820026A (en) | Thermocouple combined type speed potential probe and measuring method | |
| US3693440A (en) | Electromagnetic flowmeter | |
| CN113155221B (en) | Liquid metal flowmeter and lead bismuth cooling system | |
| Nakoryakov et al. | Electrochemical method for measuring turbulent characteristics of gas-liquid flows | |
| Bertola | Two-phase flow measurement techniques | |
| US11796364B2 (en) | Coriolis measuring sensor of a Coriolis measuring instrument and a Coriolis measuring instrument | |
| CN113884136A (en) | Separated temperature-velocity coupling potential probe and preparation and measurement method thereof | |
| CN113791458A (en) | Constant temperature field geophysical prospecting device with known inlet pipeline | |
| Bühler et al. | Development of combined temperature–electric potential sensors |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |