Liquid metal flow pressure, differential pressure measuring system and measuring method

Abstract

The application provides a liquid metal flow pressure and differential pressure measuring system and measuring method, which comprises a liquid metal loop (9), a first valve (1), a pressure lead pipe (4), a liquid storage pipe (5), a second valve (2), a third valve (3), an oil injection pipe (6), a bend pipe (7) and a pressure transmitter (8). The liquid metal loop (9) is connected with one end of the first valve (1). The other end of the first valve (1) is connected with the liquid storage tank (5) through the pressure lead pipe (4). The liquid storage tank (5) is connected with one end of the second valve (2). The other end of the second valve (2) is connected with one end of the third valve (3) and the pressure transmitter (8) through the bend pipe (7) respectively. The other end of the third valve (3) is connected with the oil injection pipe (6).

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of multiphase flow parameter measurement and the field of nuclear reactor thermal hydraulics, in particular to a liquid metal flow pressure and differential pressure measurement system and method. BACKGROUND

[0002] Under the background of the national strategy of "carbon peak" and "carbon neutrality", nuclear energy, as a clean energy for sustainable development, has a good development prospect. In the safe operation of nuclear reactors, pressure measurement is essential. In addition to obtaining nuclear reactor operating parameters and optimizing reactor design, it can also effectively monitor the safety and stability of operation and prevent possible safety problems.

[0003] However, in the fourth generation nuclear reactor mainly selected as a lead-based fast reactor, high-temperature and high-viscosity liquid metal with corrosion brings great difficulty to pressure measurement. On the one hand, the traditional pressure gauge cannot adapt to harsh measurement conditions, and on the other hand, the existing pressure gauge that can measure liquid metal not only has a complex structure, is not easy to operate, and has a very high cost, which is not friendly to the technology research and development of installation and researchers. Therefore, at present, it is necessary to develop a liquid metal flow pressure measurement system with simple structure, not complicated operation, easy to process and low cost to realize the measurement of the pressure in the liquid metal flow process. SUMMARY

[0004] In view of the defects in the prior art, the purpose of the present application is to provide a liquid metal flow pressure and differential pressure measurement system and method.

[0005] According to the liquid metal flow pressure measurement system provided by the present application, the liquid metal loop 9, the first valve 1, the pressure lead pipe 4, the liquid storage tank 5, the second valve 2, the third valve 3, the oil injection pipe 6, the elbow pipe 7 and the pressure transmitter 8 are connected in series.

[0006] The liquid metal loop 9 is connected to one end of the first valve 1; the other end of the first valve 1 is connected to the liquid storage tank 5 through the pressure lead pipe 4; the liquid storage tank 5 is connected to one end of the second valve 2; the other end of the second valve 2 is connected to one end of the third valve 3 and connected to the pressure transmitter 8 through the elbow pipe 7; the other end of the third valve 3 is connected to the oil injection pipe 6.

[0007] Preferably, the pressure lead pipe 4, the liquid storage tank 5, the oil injection pipe 6 and the elbow pipe 7 are all made of 316L stainless steel with good corrosion resistance.

[0008] Preferably, the pressure transmitter 8 adopts a single crystal silicon resonant sensor.

[0009] According to the liquid metal flow pressure measuring method provided by the application, the above-mentioned liquid metal flow pressure measuring system is used to perform the following steps:

[0010] Step S1: close the second valve 2 and the third valve 3, open the first valve 1, start the vacuum pump of the liquid metal loop 9, and vacuumize the pressure lead pipe 4 and the liquid storage tank 5;

[0011] Step S2: open the third valve 3, keep the second valve 2 closed, inject high-temperature guide pressure oil through the oil injection pipe 6, and close the third valve 3 after the high-temperature guide pressure oil is filled in the elbow pipe 7;

[0012] Step S3: after the liquid metal fills the liquid metal loop 9, open the first valve 1, and the liquid metal rises to the second valve 2 at the upper part of the liquid storage tank 5 in the pressure lead pipe 4; open the second valve 2 to make the liquid metal contact the high-temperature guide pressure oil, and the contact position is located at the second valve 2;

[0013] Step S4: start the pressure transmitter to realize pressure measurement.

[0014] Preferably, the high-temperature guide pressure oil uses silicon oil.

[0015] According to the liquid metal flow pressure difference measuring system provided by the application, the liquid metal loop 9, the first valve 1, the pressure lead pipe 4, the liquid storage tank 5, the second valve 2, the third valve 3, the oil injection pipe 6, the elbow pipe 7, the pressure difference transmitter 10, the fourth valve 11, the second pressure lead pipe 14, the second liquid storage tank 15, the fifth valve 12, the sixth valve 13, and the second oil injection pipe 16 are included.

[0016] The liquid metal loop 9 is connected with one end of the first valve 1; the other end of the first valve 1 is connected with the liquid storage tank 5 through the pressure lead pipe 4; the liquid storage tank 5 is connected with one end of the second valve 2; the other end of the second valve 2 is connected with one end of the third valve 3 and connected with the pressure difference transmitter 10 through the elbow pipe 7; the other end of the third valve 3 is connected with the oil injection pipe 6.

[0017] The liquid metal loop 9 is connected with one end of the fourth valve 11; the other end of the fourth valve 11 is connected with the second liquid storage tank 15 through the second pressure lead pipe 14; the second liquid storage tank 15 is connected with one end of the fifth valve 12; the other end of the fifth valve 12 is connected with one end of the sixth valve 13 and connected with the pressure difference transmitter 10 through the elbow pipe 7; the other end of the sixth valve 13 is connected with the second oil injection pipe 16.

[0018] According to the liquid metal flow pressure difference measurement method provided by the application, the liquid metal flow pressure difference measurement system is used to perform the following steps.

[0019] Step S1: the second valve 2, the third valve 3, the fifth valve 12 and the sixth valve 13 are closed, the first valve 1 and the fourth valve 11 are opened, the liquid metal loop 9 vacuum pump is started, and the pressure lead pipe 4, the liquid storage tank 5, the second pressure lead pipe 14 and the second liquid storage tank 15 are pumped to vacuum.

[0020] Step S2: the third valve 3 and the sixth valve 13 are opened respectively, the second valve 2 and the fifth valve 12 are kept closed, the oil injection pipe 6 and the second oil injection pipe 16 are used to inject high-temperature guide oil respectively, and when the high-temperature guide oil is filled in the elbow pipe 7, the third valve 3 and the sixth valve 13 are closed respectively.

[0021] Step S3: after the liquid metal fills the liquid metal loop 9, the first valve 1 and the fifth valve 12 are opened respectively, the liquid metal rises to the upper part of the second valve 2 of the liquid storage tank 5 in the pressure lead pipe 4 and rises to the upper part of the fifth valve 12 of the second liquid storage tank 15 in the second pressure lead pipe 14, and the second valve 2 and the fifth valve 12 are opened respectively to make the liquid metal contact with the high-temperature guide oil, and the contact position is located at the second valve 2 and the fifth valve 12.

[0022] Step S4: the differential pressure transmitter is started to measure the differential pressure.

[0023] Preferably, the heights of the second valve 2 and the fifth valve 12 and the liquid storage tank 5 and the second liquid storage tank 15 are the same.

[0024] Compared with the prior art, the application has the following beneficial effects:

[0025] 1. The application realizes the measurement of the flow pressure of liquid metal with high temperature and strong corrosion by simple pipeline connection, which helps to meet the pressure measurement demand of the nuclear reactor field and researchers.

[0026] 2. The application uses a conventional pressure transmitter to replace a special high-temperature high-viscosity corrosion-resistant pressure transmitter, which greatly reduces the measurement cost.

[0027] 3. The application realizes the measurement of the flow pressure of liquid metal with high temperature and strong corrosion by the form of an external circuit of the pressure gauge, compared with the existing liquid metal pressure measurement device, the application has the advantages of simple structure, simple operation, greatly reduced cost, meeting the measurement demand of the liquid metal pressure in the nuclear reactor and reducing the experimental cost of researchers. Attached Figure Description

[0028] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0029] Figure 1 This is a schematic diagram of the measurement system for the pressure of liquid metal flow, which is the main feature of this invention.

[0030] Figure 2 This is a schematic diagram of the measurement system for pressure difference during liquid metal flow, which is the main feature of this invention.

[0031] Wherein, 1-first valve; 2-second valve; 3-third valve; 4-pressure tapping pipe; 5-liquid storage tank; 6-oil injection pipe; 7-bend; 8-pressure transmitter; 9-liquid metal circuit; 10-differential pressure transmitter; 11-fourth valve; 14-second pressure tapping pipe; 15-second liquid storage tank; 12-fifth valve; 13-sixth valve; 16-second oil injection pipe. Detailed Implementation

[0032] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0033] The principle of the liquid metal flow pressure and differential pressure measurement system and method of this invention includes the silicone oil pressure guiding principle. Silicone oil is used as the filling fluid for electronic instruments. Utilizing its advantages such as high flash point (high temperature resistance, non-volatile, oxidation resistance), low freezing point (low temperature resistance, non-freezing), low temperature viscosity coefficient, and non-corrosiveness, silicone oil is almost universally used in the instrument manufacturing industry as the filling fluid for the capillary tube or measuring chamber of diaphragm pressure and differential pressure transmitters, as well as for diaphragm pressure gauges. In this invention, because the liquid is hot, highly viscous, and highly corrosive, it cannot directly contact the pressure transmitter body; therefore, a high-temperature pressure guiding oil is required as the pressure transmission medium.

[0034] The storage tank, being larger in volume than the pressure tapping pipe and bend, is used to reduce fluctuations in the liquid metal level and buffer pressure changes. When the measurement is complete, the liquid metal level drops, and the storage tank serves to store the silicone oil, preventing it from entering the liquid metal flow loop along the pipeline.

[0035] Since liquid metal has a high temperature, silicone oil will conduct some of the heat from the liquid metal. In order to reduce the temperature of silicone oil as much as possible so as not to damage the pressure transmitter, a section of bent pipe is installed to enhance the heat dissipation of silicone oil.

[0036] Example 1

[0037] According to the present invention, a system for measuring the pressure of liquid metal flow is provided, such as... Figure 1 As shown, it includes: liquid metal circuit 9, first valve 1, pressure tapping pipe 4, liquid storage tank 5, second valve 2, third valve 3, oil injection pipe 6, bend pipe 7, and pressure transmitter 8.

[0038] The liquid metal circuit 9 is connected to one end of the first valve 1; the other end of the first valve 1 is connected to the liquid storage tank 5 through the pressure tap 4; the liquid storage tank 5 is connected to one end of the second valve 2; the other end of the second valve 2 is connected to one end of the third valve 3 and to the pressure transmitter 8 through the bend 7; the other end of the third valve 3 is connected to the oil injection pipe 6.

[0039] Specifically, the pressure tapping pipe 4, the liquid storage tank 5, the oil injection pipe 6, and the bend pipe 7 are all made of 316L stainless steel with good corrosion resistance.

[0040] Specifically, the pressure transmitter 8 uses a single-crystal silicon resonant sensor.

[0041] To obtain optimal measurement data, the inner diameter of pipe sections such as pressure tap 4 and bend 7 is 8 mm, and the wall thickness is 1 mm. The storage tank 5 is 140 mm high, has an inner diameter of 55 mm, and a wall thickness of 2.5 mm. The structural parameters of the pipeline can be optimized and adjusted according to the size of the liquid metal circuit 9 to be measured and the structure of the pressure transmitter 8.

[0042] The present invention has a simple structure and realizes the measurement of pressure of high-temperature, high-viscosity, and corrosive liquid metal flow by ordinary pressure gauge through an external circuit.

[0043] According to the present invention, a method for measuring the flow pressure of liquid metal is provided, which is realized by the above-mentioned liquid metal flow pressure measurement system. High-temperature pressure-conducting oil is injected through the oil injection pipe 6 in a specific stage to achieve pressure transmission, heat insulation and corrosion prevention. The three identical valves 1, 2 and 3 achieve contact between liquid metal and silicone oil by opening and closing at different stages.

[0044] The method for measuring the liquid metal flow pressure includes:

[0045] Step S1: Close the second valve 2 and the third valve 3, open the first valve 1, start the vacuum pump of the liquid metal circuit 9, and evacuate the pressure pipe 4 and the liquid storage tank 5 to a vacuum.

[0046] Step S2: Open the third valve 3, keep the second valve 2 closed, and inject high-temperature pressure-conducting oil through the oil injection pipe 6. After the bend pipe 7 is filled with high-temperature pressure-conducting oil, close the third valve 3.

[0047] Step S3: After the liquid metal circuit 9 is filled with liquid metal, the first valve 1 is opened. The liquid metal rises in the pressure pipe 4 to the second valve 2 at the top of the storage tank 5. The liquid metal comes into contact with the high temperature pressure-conducting oil when the second valve 2 is opened. The contact position is located at the second valve 2.

[0048] Step S4: Start the pressure transmitter to measure the pressure.

[0049] Specifically, the high-temperature pressure-conducting oil uses silicone oil.

[0050] Example 2

[0051] According to the present invention, a system for measuring the pressure difference during liquid metal flow is provided, such as... Figure 2 As shown, it includes: liquid metal circuit 9, first valve 1, pressure tapping pipe 4, liquid storage tank 5, second valve 2, third valve 3, oil injection pipe 6, bend pipe 7, differential pressure transmitter 10, fourth valve 11, second pressure tapping pipe 14, second liquid storage tank 15, fifth valve 12, sixth valve 13, and second oil injection pipe 16.

[0052] The liquid metal circuit 9 is connected to one end of the first valve 1; the other end of the first valve 1 is connected to the liquid storage tank 5 through the pressure tapping pipe 4; the liquid storage tank 5 is connected to one end of the second valve 2; the other end of the second valve 2 is connected to one end of the third valve 3 and to the differential pressure transmitter 10 through the bend pipe 7; the other end of the third valve 3 is connected to the oil injection pipe 6.

[0053] The liquid metal circuit 9 is connected to one end of the fourth valve 11; the other end of the fourth valve 11 is connected to the second liquid storage tank 15 through the second pressure tap 14; the second liquid storage tank 15 is connected to one end of the fifth valve 12; the other end of the fifth valve 12 is connected to one end of the sixth valve 13 and to the differential pressure transmitter 10 through the bend 7; the other end of the sixth valve 13 is connected to the second oil injection pipe 16.

[0054] According to the method for measuring the differential pressure of liquid metal flow provided by the present invention, the following steps are performed using the liquid metal differential pressure measurement system described above:

[0055] Step S1: close the second valve 2, the third valve 3, the fifth valve 12 and the sixth valve 13, open the first valve 1 and the fourth valve 11, start the vacuum pump of the liquid metal circuit 9, and vacuumize the pressure lead pipe 4, the liquid tank 5, the second pressure lead pipe 14 and the second liquid tank 15;

[0056] Step S2: open the third valve 3 and the sixth valve 13 respectively, keep the second valve 2 and the fifth valve 12 closed, inject high-temperature guide oil through the oil injection pipe 6 and the second oil injection pipe 16 respectively, and close the third valve 3 and the sixth valve 13 respectively after the bend pipe 7 is filled with high-temperature guide oil;

[0057] Step S3: after the liquid metal fills the liquid metal circuit 9, open the first valve 1 and the fifth valve 12 respectively, and the liquid metal rises to the upper part of the second valve 2 of the liquid tank 5 and the upper part of the fifth valve 12 of the second liquid tank 15 in the pressure lead pipe 4 and the second pressure lead pipe 14 respectively; open the second valve 2 and the fifth valve 12 respectively to make the liquid metal contact with the high-temperature guide oil, and the contact position is at the second valve 2 and the fifth valve 12;

[0058] Step S4: start the differential pressure transmitter to measure the differential pressure.

[0059] Preferably, the heights of the second valve 2 and the fifth valve 12, and the liquid tank 5 and the second liquid tank 15 are the same, so as to ensure that the contact liquid level heights of the liquid metal and the silicon oil in the pressure lead pipe 4 and the second pressure lead pipe 14 are the same, and the influence of the gravity differential pressure of the liquid metal is ignored.

[0060] The present application can realize pressure measurement through the external circuit without complicated operation, and can meet the measurement of the flow pressure of high-temperature, high-viscosity and strong-corrosion liquid metal.

[0061] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the above specific embodiments, and various changes or modifications can be made by those skilled in the art within the scope of the claims, which do not affect the essential content of the present application. The embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily without conflict.

Claims

1. A system for measuring the flow pressure of a liquid metal, characterized by It comprises: a liquid metal loop (9), a first valve (1), a pressure lead pipe (4), a liquid storage tank (5), a second valve (2), a third valve (3), an oil injection pipe (6), a bend pipe (7), and a pressure transmitter (8); the liquid metal loop (9) is connected with one end of the first valve (1); the other end of the first valve (1) is connected with the liquid storage tank (5) through the pressure lead pipe (4); the liquid storage tank (5) is connected with one end of the second valve (2); the other end of the second valve (2) is connected with one end of the third valve (3) and the differential pressure transmitter (10) through the bend pipe (7) respectively; the other end of the third valve (3) is connected with the oil injection pipe (6); The liquid storage tank has a larger volume than the pressure lead pipe and the bend pipe.

2. The liquid metal flow pressure measurement system of claim 1, wherein, The pressure lead pipe (4), the liquid storage tank (5), the oil injection pipe (6), and the bend pipe (7) are made of 316L stainless steel with good corrosion resistance.

3. The liquid metal flow pressure measurement system of claim 1, wherein, The pressure transmitter (8) adopts a single crystal silicon resonant sensor.

4. A method of measuring the flow pressure of a liquid metal, characterized by, The liquid metal flow pressure measurement system according to any one of claims 1 to 3 performs the following steps: Step S1: close the second valve (2) and the third valve (3), open the first valve (1), start the vacuum pump of the liquid metal loop (9), and vacuumize the pressure lead pipe (4) and the liquid storage tank (5); Step S2: open the third valve (3), keep the second valve (2) closed, inject high-temperature guide oil through the oil injection pipe (6), and close the third valve (3) when the bend pipe (7) is filled with high-temperature guide oil; Step S3: after the liquid metal fills the liquid metal loop (9), open the first valve (1), and the liquid metal rises in the pressure lead pipe (4) to the upper part of the liquid storage tank (5) at the second valve (2), open the second valve (2), and the liquid metal contacts the high-temperature guide oil at the second valve (2); Step S4: start the pressure transmitter to measure the pressure.

5. The method of measuring the flow pressure of a liquid metal according to claim 4, wherein The high-temperature guide oil uses silicon oil.

6. A system for measuring the pressure differential of a flow of liquid metal, characterized in that it comprises: It comprises: a liquid metal loop (9), a first valve (1), a pressure lead pipe (4), a liquid storage tank (5), a second valve (2), a third valve (3), an oil injection pipe (6), a bend pipe (7), a differential pressure transmitter (10), a fourth valve (11), a second pressure lead pipe (14), a second liquid storage tank (15), a fifth valve (12), a sixth valve (13), and a second oil injection pipe (16); the liquid metal loop (9) is connected with one end of the first valve (1); the other end of the first valve (1) is connected with the liquid storage tank (5) through the pressure lead pipe (4); the liquid storage tank (5) is connected with one end of the second valve (2); the other end of the second valve (2) is connected with one end of the third valve (3) and the differential pressure transmitter (10) through the bend pipe (7) respectively; the other end of the third valve (3) is connected with the oil injection pipe (6); The liquid metal loop (9) is connected with one end of the fourth valve (11); the other end of the fourth valve (11) is connected with the second liquid storage tank (15) through the second pressure lead pipe (14); the second liquid storage tank (15) is connected with one end of the fifth valve (12); the other end of the fifth valve (12) is connected with one end of the sixth valve (13) and connected with the differential pressure transmitter (10) through the elbow pipe (7); the other end of the sixth valve (13) is connected with the second oil injection pipe (16); The liquid storage tank has a larger volume than the pressure lead pipe and the elbow pipe.

7. A method of measuring the pressure differential of a flow of liquid metal, characterized in that, The liquid metal flow pressure difference measurement system of claim 6 performs the following steps: Step S1: close the second valve (2), the third valve (3), the fifth valve (12) and the sixth valve (13), open the first valve (1) and the fourth valve (11), start the vacuum pump of the liquid metal loop (9), and vacuumize the pressure lead pipe (4), the liquid storage tank (5), the second pressure lead pipe (14) and the second liquid storage tank (15); Step S2: open the third valve (3) and the sixth valve (13) respectively, keep the second valve (2) and the fifth valve (12) closed, inject high-temperature guide oil through the oil injection pipe (6) and the second oil injection pipe (16) respectively, and close the third valve (3) and the sixth valve (13) respectively after the elbow pipe (7) is filled with high-temperature guide oil; Step S3: after the liquid metal fills the liquid metal loop (9), open the first valve (1) and the fifth valve (12) respectively, and the liquid metal rises to the second valve (2) at the upper part of the liquid storage tank (5) in the pressure lead pipe (4) and to the fifth valve (12) at the upper part of the second liquid storage tank (15) in the second pressure lead pipe (14) respectively; open the second valve (2) and the fifth valve (12) respectively, and the liquid metal contacts the high-temperature guide oil at the positions of the second valve (2) and the fifth valve (12); Step S4: start the differential pressure transmitter to measure the differential pressure.

8. The method of claim 7, wherein the liquid metal flow pressure differential is measured by a pressure sensor. The heights of the second valve (2) and the fifth valve (12), and the heights of the liquid storage tank (5) and the second liquid storage tank (15) are the same.

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