A high-temperature liquid metal throttling flow measurement system and method using electromagnetic excitation

Abstract

The present invention provides an electromagnetically excited high-temperature liquid metal throttling flow measurement system and method, belonging to the field of flow measurement technology. The method comprises: connecting direct current to an electromagnetic excitation coil to generate a direct current magnetic field around a non-metallic pipe; this magnetic field causes the liquid metal in the pipe to produce a throttling effect, resulting in a contraction in its flow rate and a pressure differential; using a differential pressure detection module to detect the liquid metal's pressure differential, and using a temperature sensor to detect the liquid metal's temperature in the pipe, to correct the flow coefficient; calculating the relationship between the liquid metal's flow rate and flow rate according to the Bernoulli equation; and using temperature to perform temperature compensation on the liquid metal's fluid density and incorporate it into the relationship between the liquid metal's flow rate and flow rate. Because the physical properties of liquid metal (such as density) vary with temperature, directly affecting flow measurement results, the present invention corrects measurement errors by performing temperature compensation on the liquid metal's flow rate, thereby obtaining more accurate flow data.

Description

Technical Field

[0001] The present invention relates to the technical field of flow measurement, and in particular to an electromagnetically excited high-temperature liquid metal throttling flow measurement system and method. Background Art

[0002] High-temperature liquid metals possess excellent electrical and thermal conductivity, plasticity, and chemical stability, and are widely used in various fields. In the nuclear industry, they are often used as coolants in high-temperature reactors and nuclear power plants; in aerospace, they are used in the manufacture of engine components and fuel; and in alloy preparation, they are often used in the synthesis of new materials and catalysis. Measuring the flow rate of high-temperature liquid metals is crucial for ensuring a stable production process and product quality. Due to the high temperature and strong corrosiveness of high-temperature liquid metals, flow measurement differs from that of other fluids and requires selection based on the characteristics of the high-temperature liquid metal, flow rate, and pipe diameter.

[0003] Currently, commonly used flow measurement technologies are mainly divided into measurement technologies with interfering parts and measurement technologies with non-interfering parts. Measurement technologies with interfering parts refer to the flowmeter used containing obstructions. Commonly used interfering liquid metal flow measurement technologies include turbine flowmeter method, vortex flowmeter method, orifice flowmeter method, optical probe flowmeter method, etc. Measurement technologies without interfering parts refer to the flowmeter used containing no obstructions. This type of flowmeter will not affect the flow pattern and flow state of the measured fluid during the measurement process and has no pressure loss. Therefore, it has outstanding advantages when measuring high-temperature liquid metal. In recent years, measurement technologies without interfering parts have developed very rapidly. Common non-interfering liquid metal flow measurement technologies include Coriolis mass flowmeter, electromagnetic flowmeter, ultrasonic flowmeter, photography, X-ray photography, etc.

[0004] It aims to solve the measurement problems of flow velocity distribution and flow rate of high-temperature liquid metal in pipes, such as high measurement environment temperature, conductivity of high-temperature liquid metal, wetting and corrosion between high-temperature liquid metal and the wall, and large measurement pipe diameter. Although existing electromagnetic flowmeters are suitable for conductive fluids, they typically rely on induced electromotive force measurement in a uniform magnetic field. This makes it impossible to distinguish between flow velocity changes and conductivity fluctuations in high-temperature liquid metal. Furthermore, the signal-to-noise ratio significantly decreases at low flow rates (<0.1 m / s), making it difficult to meet precision control requirements. Ultrasonic flowmeters experience reduced acoustic coupling performance at high temperatures and lack sensitivity at low flow rates. Traditional orifice flowmeters rely on a throttling structure, which is prone to thermal expansion and geometric deformation at high temperatures. The mechanical blunt body of a vortex flowmeter is susceptible to damage due to the high temperature, strong corrosiveness, and conductive properties of liquid metal. This damage easily leads to localized solidification and impurity deposition, and also hinders the stable operation of optical or thermal sensors. While inducing eddy currents using a high-frequency AC electromagnetic field (>1 kHz) can avoid mechanical wear, the alternating magnetic field can easily induce the skin effect of the liquid metal, resulting in instability in the effective throttling area. Traditional upstream and downstream pressure measurement methods, under a DC magnetic field, suffer from uneven magnetic field gradient distribution (simulations show a 15% difference in magnetic induction intensity between the pipe center and the wall). This results in a differential pressure signal that is sensitive to magnetic field position, resulting in repeatability errors exceeding ±2%. Existing technologies struggle to balance long-term structural stability in high-temperature environments with the high-precision measurement requirements for transient flows (such as turbulent and pulsating flows). Therefore, there is an urgent need for a high-temperature liquid metal flow measurement solution that eliminates physical throttling components, avoids corrosion and wear, adapts to extreme environments, and can accurately measure flow. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the present invention aims to provide an electromagnetically excited high-temperature liquid metal throttling flow measurement system and method.

[0006] To achieve the above objectives, the present invention provides the following solutions:

[0007] An electromagnetically excited high-temperature liquid metal throttling flow measurement system, comprising:

[0008] The electromagnetic excitation coil is wound around the non-metallic pipe and is used to generate a DC magnetic field around the non-metallic pipe. When the liquid metal passes through the non-metallic pipe, it will be affected by the DC magnetic field and produce a throttling effect, causing the liquid metal flow rate to shrink and generate a pressure difference;

[0009] The differential pressure detection module is arranged on both sides of the electromagnetic excitation coil and is used to monitor the differential pressure of the liquid metal in real time;

[0010] Temperature sensor, used to detect the temperature of liquid metal;

[0011] The signal processing and solving unit is used to calculate the flow rate of the liquid metal according to the differential pressure and temperature of the liquid metal.

[0012] Preferably, the electromagnetic excitation coil adopts a spiral structure, the inner layer is a pure copper wire, the outer layer is covered with a high-temperature resistant insulation layer, and the number of coil turns N=200.

[0013] The present invention also provides a method for measuring the throttling flow of high-temperature liquid metal using electromagnetic excitation, comprising:

[0014] Step 1: Connect direct current to the electromagnetic excitation coil to generate a direct current magnetic field around the non-metallic pipe. This direct current magnetic field will cause the liquid metal to have a throttling effect, causing its flow rate to shrink and generate differential pressure;

[0015] Step 2: Use the differential pressure detection module to detect the differential pressure of the liquid metal, and use the temperature sensor to detect the temperature of the liquid metal in the tube;

[0016] Step 3: Calculate the relationship between liquid metal flow rate and flow rate according to Bernoulli equation;

[0017] Step 4: Using the temperature to perform temperature compensation correction on the fluid density of the liquid metal to obtain the temperature compensated liquid metal fluid density;

[0018] Step 5: Substitute the temperature-compensated liquid metal fluid density into the relationship between liquid metal flow velocity and flow rate to obtain the liquid metal flow rate in the target pipeline.

[0019] Preferably, step 3 includes:

[0020] Considering the DC magnetic field as a non-contact throttling device, when the liquid metal moves in the DC magnetic field, throttling of the liquid metal in the pipeline occurs:

[0021]

[0022] in, is the speed before the throttle, is the speed after the throttle, is the pressure difference before and after the throttling element, is the density of liquid metal fluid.

[0023] From the incompressible continuity equation:

[0024]

[0025] in, is the speed before the throttle, is the cross-sectional area of ​​the pipe, The cross-sectional area of ​​the fluid flow where the flow velocity is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; The fluid velocity that causes flow contraction at the throttling element, is the speed after the throttle, is the cross-sectional area of ​​the fluid behind the throttling device.

[0026] Since the cross-sectional area of ​​the fluid behind the throttle The area is difficult to determine, so the cross-sectional area of ​​the fluid flow that produces flow rate contraction at the throttling part is used. Instead, taking into account the mechanical energy loss, a coefficient correction is used:

[0027]

[0028] in, is the cross-sectional area of ​​the pipe, The cross-sectional area of ​​the fluid flow where the flow velocity is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; The fluid velocity that causes flow contraction at the throttling element, is the cross-sectional area of ​​the fluid behind the throttling element, is the pressure difference before and after the throttling element, is the density of liquid metal fluid, is the correction factor.

[0029] Let the flow coefficient Expressed as:

[0030]

[0031] in, Indicates the flow coefficient, which is calibrated by experiment; represents the correction factor; is the cross-sectional area of ​​the pipe; It is the cross-sectional area of ​​the fluid flow where the flow rate shrinks at the throttling device, which is equivalent to the original opening area of ​​the throttling device and is determined by simulation.

[0032]

[0033] in, Indicates the flow coefficient, which is calibrated by experiment; The cross-sectional area of ​​the fluid flow where the flow rate is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; is the pressure difference before and after the throttling element, is the density of liquid metal fluid, Indicates the liquid metal flow rate.

[0034] Preferably, in step 4, the formula is used:

[0035]

[0036] The temperature compensation correction is performed on the density of the liquid metal fluid to obtain the corrected liquid metal density; wherein, It represents the density of liquid metal fluid after temperature compensation correction, represents the density of liquid metal before correction, represents the coefficient of thermal expansion, Indicates the current temperature of the liquid metal, represents the initial temperature of liquid metal.

[0037] The present invention also provides an electronic device, comprising a bus, a transceiver, a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein the transceiver, the memory, and the processor are connected via the bus, and wherein the computer program, when executed by the processor, implements the steps in the above-mentioned electromagnetically excited high-temperature liquid metal throttling flow measurement method.

[0038] The present invention also provides a computer-readable storage medium having a computer program stored thereon, characterized in that when the computer program is executed by a processor, the steps in the above-mentioned electromagnetically excited high-temperature liquid metal throttling flow measurement method are implemented.

[0039] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0040] The present invention provides an electromagnetically excited high-temperature liquid metal throttling flow measurement system and method. Compared with the existing technology, since the physical properties of liquid metal (such as density) will change with temperature, which directly affects the flow measurement results, the present invention can correct measurement errors through temperature compensation and obtain more accurate flow data. In addition, the present invention uses electromagnetic excitation coils to produce a throttling effect on liquid metal, realizing non-contact flow control. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0042] Figure 1 A schematic diagram of the overall structure of the system provided by the present invention;

[0043] Figure 2 The COMSOL simulation magnetic field distribution diagram provided by the present invention;

[0044] Figure 3 The flow rate-pressure difference characteristic curve provided by the present invention;

[0045] Figure 4 The pressure distribution diagram in the pipe provided by the present invention;

[0046] Figure 5 This is a flow measurement process diagram provided by the present invention. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0048] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0049] The terms "first," "second," "third," and "fourth," etc., in the specification, claims, and drawings of this application are used to distinguish between different items, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a statement that a sequence of steps, a process, or a method is included is not limited to the listed steps but may optionally include steps not listed, or may optionally include other steps inherent to the process, method, product, or apparatus.

[0050] In order to make the above-mentioned objectives, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] See also Figure 1-5 , an electromagnetically excited high-temperature liquid metal throttling flow measurement system, comprising:

[0052] The electromagnetic excitation coil is wound around the non-metallic pipe and is used to generate a DC magnetic field around the non-metallic pipe. When the liquid metal passes through the non-metallic pipe, it will be affected by the DC magnetic field and cause throttling, thereby causing the liquid metal flow rate to shrink and generate a pressure difference;

[0053] The differential pressure detection module is arranged on both sides of the electromagnetic excitation coil and is used to monitor the differential pressure of the liquid metal in real time;

[0054] Temperature sensor, used to detect the temperature of liquid metal;

[0055] The signal processing and solving unit is used to calculate the flow rate of the liquid metal according to the differential pressure and temperature of the liquid metal.

[0056] In practical applications, an excitation coil wrapped around a non-metallic (ceramic) pipe generates a stable DC magnetic field around the pipe by applying a 20A DC current to the excitation coil. Due to the conductivity of the liquid metal, as it passes through the pipe, the movement of the liquid metal is affected by the magnetic field, causing a throttling effect within the pipe. This causes the high-temperature liquid metal to shrink in flow rate. The electromagnetic excitation coil acts as a non-contact throttling device, creating a pressure differential across the device. The inner layer of the electromagnetic excitation coil is a pure copper conductor, with an outer layer coated with a high-temperature resistant protective layer to prevent damage. Current flows through the conductor, and the transmitting coil generates a magnetic field.

[0057] High-precision differential pressure sensors are installed symmetrically on the left and right sides of the electromagnetic coil area to monitor the periodic pressure fluctuations of the high-temperature liquid metal in real time. The temperature compensation unit is mainly used to correct the thermal deformation error of the diaphragm in real time.

[0058] Use the signal processing and solution unit to amplify, filter and remove noise on the collected differential pressure signal;

[0059] The pipeline unit is made of non-magnetic high-temperature resistant material (such as high-temperature resistant ceramics), has an inner diameter of 40mm, and is used to transport high-temperature liquid metal fluid.

[0060] In actual applications, the electromagnetic excitation coil is wrapped around a non-metallic pipe to prevent the coil from being directly exposed to the liquid metal fluid and being damaged and corroded by high temperature, thereby improving the service life of the equipment. In addition, a silicon nitride coating (0.5mm) is applied to the inner wall of the non-metallic pipe to reduce the adhesion of liquid metal, and the electromagnetic coil is wrapped with a high-temperature resistant coating material.

[0061] The specific operation process of the electromagnetically excited high-temperature liquid metal throttling flow measurement system of the present invention is as follows:

[0062] Step 1: The electromagnetic excitation coil adopts a spiral structure, with an inner layer of pure copper wire (radius 2.5mm) and an outer layer covered with an inner high-temperature insulation layer (thickness 0.5mm). Through simulation optimization, the number of coil turns N = 200, so that the magnetic induction intensity in the center of the pipeline reaches 0.68T, and the gradient distribution uniformity error is less than 5%. 20A DC excitation is applied to the two sets of electromagnetic excitation coils at an excitation frequency of 100Hz.

[0063] Step 2: The double-sided differential pressure detection module consists of a differential pressure detection device and a temperature compensation module. The differential pressure taps are symmetrically arranged on both sides of the axial centerline of the electromagnetic coil (with a spacing of approximately 50 mm). Finite element simulation analysis has verified that the effect of the magnetic field gradient on the double-sided pressure difference can offset each other by more than 90% under this spacing. The differential pressure diaphragm is made of tungsten-doped sapphire material (thermal expansion coefficient 4.6×10⁻6 / ℃), and the pipe substrate material (silicon nitride, thermal expansion coefficient 3.2×10⁻ 6 / ℃) matching, combined with Pt100 temperature sensor to correct diaphragm thermal deformation error in real time, and synchronously collect double-side differential pressure P, fluid temperature T;

[0064] Step 3: The signal processing and calculation unit processes the pressure differential signal and temperature obtained by the double-side differential pressure detection module. Based on a digital lock-in amplifier (bandwidth 10kHz) and an embedded flow calculation engine, the real-time conductivity of the liquid metal is calculated, and the flow rate is calculated using the flow settlement engine.

[0065] Step 4: Conduct simulation analysis and verification. Based on COMSOL Multiphysics multi-physics simulation software, establish a flow measurement model of a pipe (40mm diameter), a coil (200 turns), and a liquid metal (lead-bismuth alloy). The inlet flow rate is 0.1-1m / s, the fluid temperature is 600℃, and the magnetic field intensity distribution is as follows: Figure 2 As shown, B=0.68T at the center of the pipeline and B=0.5T at the edge. The gradient uniformity meets the design requirements, the pressure difference is proportional to the square of the flow velocity, and the theoretical model is correct.

[0066] It should be noted that the detection of liquid metal flow in pipelines is a very special field. The electromagnetic excitation coil mentioned in the present invention adopts a non-contact method, which is equivalent to a non-contact throttling element, generating a pressure difference before and after the throttling element.

[0067] Direct current is applied to the excitation coil to generate a uniform and stable magnetic field around the pipeline. Then, due to the conductivity of the liquid metal, when the liquid metal passes through the pipeline, the movement of the liquid metal will be affected by the magnetic field, causing a controllable Lorentz force to be generated inside it, driving the high-temperature liquid metal to produce flow rate contraction. The electromagnetic excitation coil is equivalent to a non-contact throttling device, causing a pressure difference before and after the throttling device.

[0068] The present invention also provides an anti-interference design for an electromagnetically excited high-temperature liquid metal throttling flow measurement system. A 0.5mm thick Permalloy layer is wrapped around the periphery of the differential pressure sensor to reduce external magnetic field interference to less than 1mT. Phase-locked amplification technology is used to extract the differential pressure signal and suppress noise introduced by DC waves.

[0069] The present invention also provides a lead-bismuth alloy flow measurement system for molten salt energy storage system, wherein the coil insulation layer adopts a plasma sprayed boron nitride coating (thickness 200 ), after the corrosion test (immersion in 700℃ lead-bismuth environment for 500 hours), the insulation resistance still remains>1 The differential pressure lead pipe has a built-in self-cleaning structure, which prevents metal deposition and blockage through periodic reverse pulse airflow (nitrogen); at the flow rate of 5m³ / h, the simulation predicts =12.3kPa, measured =12.5kPa, with a deviation of 1.6%. In the dynamic response test, when the flow rate changes stepwise (2m³ / h→5m³ / h), the system response time is ≤50ms, which is better than that of traditional differential pressure gauges (>200ms).

[0070] In the embodiments of the present invention, the electromagnetic coil must be able to withstand high temperatures while generating a stable, uniform magnetic field. The electromagnetic coil is made of highly conductive copper wire with a diameter of 5 mm, and the excitation coil has 200 turns. A high-temperature protective coating is applied to the electromagnetic coil to prevent damage from the high temperature of the liquid metal.

[0071] The measuring pipe is made of high-temperature resistant, weak-electric and high-magnetic permeability materials (high-temperature resistant ceramics, etc.), which are suitable for the magnetic field generated by the electromagnetic excitation coil to better penetrate into the pipe and prevent the high temperature of the liquid metal from damaging the pipe. A layer of silicon nitride coating (0.5mm) is applied inside the pipe to prevent the high-temperature liquid metal from sticking to the wall.

[0072] Differential pressure sensors with a sampling rate of 10kHz and a resolution of 0.01Pa are placed symmetrically on both sides of the coil coverage area, spaced L apart and using electromagnetic shielding to prevent electromagnetic interference. The signal processing and settlement unit includes a digital lock-in amplifier, filter, digitizer, and embedded flow engine, which amplifies, filters, and removes noise from the differential pressure signal.

[0073] In an embodiment of the present invention, the electromagnetic excitation coil is installed by winding it around the pipe in a non-contact manner. During the installation process, a gap of about 0.1 mm is allowed between the electromagnetic excitation coil and the pipe.

[0074] The present invention also provides a method for measuring the throttling flow of high-temperature liquid metal using electromagnetic excitation, comprising:

[0075] Step 1: Connect direct current to the electromagnetic excitation coil to generate a direct current magnetic field around the non-metallic pipe;

[0076] Step 2: Use the differential pressure detection module to detect the differential pressure of the liquid metal, and use the temperature sensor to detect the temperature of the liquid metal in the tube;

[0077] Step 3: Calculate the relationship between liquid metal flow rate and flow rate according to Bernoulli equation;

[0078] In step 3, the DC magnetic field is regarded as a non-contact throttling element. When the liquid metal moves in the DC magnetic field, throttling of the liquid metal in the pipeline occurs:

[0079]

[0080] in, is the speed before the throttle, is the speed after the throttle, is the pressure difference before and after the throttling element, is the density of liquid metal fluid.

[0081] From the incompressible continuity equation:

[0082]

[0083] in, is the speed before the throttle, is the cross-sectional area of ​​the pipe, The cross-sectional area of ​​the fluid flow where the flow velocity is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; The fluid velocity that causes flow contraction at the throttling element, is the speed after the throttle, is the cross-sectional area of ​​the fluid behind the throttling device.

[0084] Since the cross-sectional area of ​​the fluid behind the throttle The area is difficult to determine, so the cross-sectional area of ​​the fluid that produces flow rate contraction at the throttling part is used. Instead, taking into account the mechanical energy loss, a coefficient correction is used:

[0085]

[0086] in, is the cross-sectional area of ​​the pipe, The cross-sectional area of ​​the fluid flow where the flow velocity is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; The fluid velocity that causes flow contraction at the throttling element, is the cross-sectional area of ​​the fluid behind the throttling element, is the pressure difference before and after the throttling element, is the density of liquid metal fluid, is the correction factor.

[0087] Let the flow coefficient Expressed as:

[0088]

[0089] in, Indicates the flow coefficient, which is calibrated by experiment; represents the correction factor; is the cross-sectional area of ​​the pipe; It is the cross-sectional area of ​​the fluid flow where the flow rate shrinks at the throttling device, which is equivalent to the original opening area of ​​the throttling device and is determined by simulation.

[0090]

[0091] in, Indicates the flow coefficient, which is calibrated by experiment; The cross-sectional area of ​​the fluid flow where the flow rate is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; is the pressure difference before and after the throttling element, is the density of liquid metal fluid, Indicates the liquid metal flow rate.

[0092] Step 4: Using the temperature to perform temperature compensation correction on the fluid density of the liquid metal to obtain the temperature compensated liquid metal fluid density;

[0093] In step 4, the formula is used:

[0094]

[0095] The temperature compensation correction is performed on the fluid density of the liquid metal to obtain the temperature-compensated liquid metal fluid density; wherein, It represents the density of liquid metal fluid after temperature compensation correction, represents the density of liquid metal before correction, represents the coefficient of thermal expansion, Indicates the current temperature of the liquid metal, represents the initial temperature of liquid metal.

[0096] The present invention further describes a method for measuring high-temperature liquid metal throttling flow using electromagnetic excitation in conjunction with specific embodiments.

[0097] Step 1: Use a differential pressure detection device to detect the pressure difference signal at the left and right symmetrical positions of the electromagnetic coil in the pipeline, and use a temperature sensor to detect the temperature of the liquid metal in the pipe;

[0098] Step 2: Use the signal processing and solving device to amplify and remove noise on the differential pressure signal, and substitute the pressure difference and temperature obtained by the differential pressure detection device into the flow formula to calculate the flow rate;

[0099] Step 3: Perform simulation analysis and verification, establish a COMSOL simulation model, couple multiple physical fields, and verify the actual reliability of the model.

[0100] In the embodiment of the present invention, the instability of liquid metal and the interference of the high temperature environment cause noise and interference in the differential pressure signal, which affects the accuracy and stability of the measurement results. Signal processing and solution are performed to improve the accuracy and stability of the measurement.

[0101] The signal processing and solution in the present invention are specifically described as follows:

[0102] Step 2.1: The electromagnetic field acts as a non-contact throttle element, generating a differential pressure before and after the throttle element:

[0103]

[0104] in, is the pressure difference before and after the throttling element, is the pressure before the throttle, It is the pressure after the throttle.

[0105] According to Bernoulli's equation:

[0106]

[0107] in, is the speed before the throttle, is the speed after the throttle, is the density of liquid metal fluid.

[0108] Arranged:

[0109]

[0110] in, is the speed before the throttle, is the speed after the throttle, is the pressure difference before and after the throttling element, is the density of liquid metal fluid.

[0111] From the incompressible continuity equation:

[0112]

[0113] in, is the speed before the throttle, is the cross-sectional area of ​​the pipe, The cross-sectional area of ​​the fluid flow where the flow velocity is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; The fluid velocity that causes flow contraction at the throttling element, is the speed after the throttle, is the cross-sectional area of ​​the fluid behind the throttling device.

[0114] Since the cross-sectional area of ​​the fluid behind the throttle The area is difficult to determine, so the cross-sectional area of ​​the fluid flow that produces flow rate contraction at the throttling part is used. Instead, taking into account the mechanical energy loss, a coefficient correction is used:

[0115]

[0116] in, is the cross-sectional area of ​​the pipe, The cross-sectional area of ​​the fluid flow where the flow velocity is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; The fluid velocity that causes flow contraction at the throttling element, is the cross-sectional area of ​​the fluid behind the throttling element, is the pressure difference before and after the throttling element, is the density of liquid metal fluid, is the correction factor.

[0117] Step 2: Obtain the relationship between flow rate and pressure difference:

[0118] Let the flow coefficient Expressed as:

[0119]

[0120] in, Indicates the flow coefficient, which is calibrated by experiment; represents the correction factor; is the cross-sectional area of ​​the pipe; It is the cross-sectional area of ​​the fluid flow where the flow rate shrinks at the throttling device, which is equivalent to the original opening area of ​​the throttling device and is determined by simulation.

[0121]

[0122] in, Indicates the flow coefficient, which is calibrated by experiment; The cross-sectional area of ​​the fluid flow where the flow rate is reduced at the throttling element is equivalent to the original opening area of ​​the throttling element and is determined by simulation; is the pressure difference before and after the throttling element, is the density of liquid metal fluid, Indicates the liquid metal flow rate.

[0123] Step 2.3: Temperature compensation:

[0124]

[0125] in, It represents the density of liquid metal fluid after temperature compensation correction, represents the density of liquid metal before correction, represents the coefficient of thermal expansion, Indicates the current temperature of the liquid metal, represents the initial temperature of liquid metal.

[0126] The physical properties of liquid metal (such as density) will change with temperature, which will directly affect the flow measurement results. The present invention can correct the measurement error through temperature compensation to obtain more accurate flow data.

[0127] The present invention also provides an electronic device, comprising a bus, a transceiver, a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein the transceiver, the memory, and the processor are connected via the bus, and is characterized in that when the computer program is executed by the processor, the steps in the above-mentioned electromagnetically excited high-temperature liquid metal throttling flow measurement method are implemented. Compared with the prior art, the beneficial effects of the electronic device provided by the present invention are the same as the beneficial effects of the electromagnetically excited high-temperature liquid metal throttling flow measurement method described in the above-mentioned technical solution, and will not be elaborated here.

[0128] The present invention also provides a computer-readable storage medium having a computer program stored thereon, characterized in that when the computer program is executed by a processor, the steps in the above-mentioned electromagnetically excited high-temperature liquid metal throttling flow measurement method are implemented. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present invention are the same as the beneficial effects of the electromagnetically excited high-temperature liquid metal throttling flow measurement method described in the above-mentioned technical solution, and will not be repeated here.

[0129] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the description of the similarities between the various embodiments. For the methods disclosed in the embodiments, since they correspond to the devices disclosed in the embodiments, the description is relatively simple, and the relevant details can be referred to the description of the devices.

[0130] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A method for measuring the throttling flow of high-temperature liquid metal using electromagnetic excitation, characterized in that: The method is applied to an electromagnetically excited high-temperature liquid metal throttling flow measurement system, wherein the system comprises: The electromagnetic excitation coil is wound around the non-metallic pipe and is used to generate a DC magnetic field around the non-metallic pipe. When the liquid metal passes through the non-metallic pipe, it will be affected by the DC magnetic field and produce a throttling effect in the pipe, causing the liquid metal flow rate to shrink and generate a pressure difference. The differential pressure detection module is arranged on both sides of the electromagnetic excitation coil and is used to monitor the differential pressure of the liquid metal in real time; Temperature sensor, used to detect the temperature of liquid metal; The signal processing and solving unit is used to calculate the flow rate of the liquid metal according to the differential pressure and temperature of the liquid metal; the electromagnetic excitation coil adopts a spiral structure, the inner layer is a pure copper conductor, the outer layer is covered with a high-temperature resistant insulation layer, and the number of coil turns N=200; The method comprises: Step 1: Connect direct current to the electromagnetic excitation coil to generate a direct current magnetic field around the non-metallic pipe; Step 2: Use the differential pressure detection module to detect the differential pressure of the liquid metal, and use the temperature sensor to detect the temperature of the liquid metal in the tube; Step 3: Calculate the relationship between liquid metal flow rate and flow rate according to Bernoulli equation; In step 3, it includes: Considering the DC magnetic field as a non-contact throttling device, when the liquid metal moves in the DC magnetic field, throttling of the liquid metal in the pipeline occurs: Wherein, v1 is the velocity before the throttle, v2 is the velocity after the throttle, ΔP is the pressure difference before and after the throttle, and ρ is the density of the liquid metal fluid; From the incompressible continuity equation: A1v1=A0v0=A2v2 Where v1 is the velocity before the throttle, A1 is the cross-sectional area of ​​the pipe, A0 is the cross-sectional area of ​​the fluid flow where the flow velocity is contracted at the throttle, which is equivalent to the original opening area of ​​the throttle and is determined by simulation; v0 is the fluid velocity where the flow velocity is contracted at the throttle, v2 is the velocity after the throttle, and A2 is the cross-sectional area of ​​the fluid after the throttle; Since the cross-sectional area A2 of the fluid behind the throttling device is difficult to determine, the cross-sectional area A0 of the fluid where the flow velocity is contracted at the throttling device is used instead. At the same time, the mechanical energy loss is taken into account and the coefficient correction is adopted: Where A1 is the cross-sectional area of ​​the pipe, A0 is the cross-sectional area of ​​the fluid flow that causes flow velocity contraction at the throttle, which is equivalent to the original opening area of ​​the throttle and is determined by simulation; v0 is the fluid velocity that causes flow velocity contraction at the throttle, A2 is the cross-sectional area of ​​the fluid behind the throttle, ΔP is the pressure difference before and after the throttle, ρ is the density of the liquid metal fluid, and C1 is the correction coefficient; Let the flow coefficient C0 be expressed as: Where C0 represents the flow coefficient, which is calibrated by experiment; C1 represents the correction coefficient; A1 is the cross-sectional area of ​​the pipe; A0 is equivalent to the original opening area of ​​the throttling element, which is determined by simulation; Where C0 is the flow coefficient, which is calibrated by experiment; A0 is the cross-sectional area of ​​the fluid flow where the flow velocity is reduced at the throttle, which is equivalent to the original opening area of ​​the throttle and is determined by simulation; ΔP is the pressure difference before and after the throttle, ρ is the density of the liquid metal fluid, and Q is the liquid metal flow rate; Step 4: Using the temperature to perform temperature compensation correction on the fluid density of the liquid metal to obtain the temperature compensated liquid metal fluid density; Step 5: Substitute the temperature-compensated liquid metal fluid density into the relationship between liquid metal flow velocity and flow rate to obtain the liquid metal flow rate in the target pipeline.

2. The electromagnetically excited high-temperature liquid metal throttling flow measurement method according to claim 1, characterized in that: In step 4, the formula is used: ρ(T)=ρ[1-α(T-T0)] The fluid density of the liquid metal is subjected to temperature compensation correction to obtain the temperature-compensated liquid metal fluid density; wherein, ρ(T) represents the liquid metal fluid density after temperature compensation correction, ρ represents the liquid metal density before correction, α represents the thermal expansion coefficient, T represents the current temperature of the liquid metal, and T0 represents the initial temperature of the liquid metal.

3. An electronic device comprising a bus, a transceiver, a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the transceiver, the memory, and the processor are connected via the bus, wherein: When the computer program is executed by the processor, the steps of the electromagnetically excited high-temperature liquid metal throttling flow measurement method according to any one of claims 1 to 2 are implemented.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the electromagnetically excited high-temperature liquid metal throttling flow measurement method according to any one of claims 1 to 2 are implemented.

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