Thermal test system for measuring flow-induced acoustic resonance of piping systems under high temperature and high pressure water

Abstract

The present invention provides a hot state test system for measuring acoustic resonance caused by flow in a pipe system under high temperature and high pressure water medium, comprising: a main pipe system and a bypass system, and the main pipe system and the bypass system are connected; the main pipe system comprises a heater, a pump, a buffer tank and a flow meter which are connected in sequence through a connecting pipe to form a loop; the bypass system comprises a bypass measurement pipeline, a dynamic pressure measurement system and a return water system; one end of the bypass measurement pipeline is connected to the connecting pipeline between the flow meter and the heater, and the other end is connected to the return water system; the other end of the return water system is connected to the connecting pipeline between the flow meter and the heater, and is located downstream of the connection port between the bypass measurement pipeline and the connecting pipeline; the dynamic pressure measurement system is used to measure the bypass measurement pipeline. The present invention helps to improve the accuracy of temperature control and the strength of the measurement signal through the coordinated use of the main pipe system and the bypass system, thereby helping to improve the validity and accuracy of the system measurement data.

Description

Technical Field

[0001] The invention relates to the technical field of reactor design, and in particular to a hot test system for measuring acoustic resonance caused by flow in a pipe system under high-temperature and high-pressure water medium. Background Art

[0002] In recent years, some nuclear power plants at home and abroad have experienced vibration of the main steam pipeline, damage to the main steam isolation valve, safety valve, atmospheric release valve and steam trap parts, or cracks in the steam dryer caused by strong acoustic resonance, which has affected the normal and stable operation of the nuclear power plant and even led to unplanned shutdown and low-power operation. Studies have shown that the high-speed flow of steam in the main steam pipeline will cause turbulence and vortexes at the bypass pipeline valve. If the main steam pipeline and its ancillary structures (valves and branches, etc.) are improperly designed or installed, when the vortex shedding frequency is close to the acoustic natural frequency of the pipeline and valve, acoustic resonance will occur. Acoustic resonance produces high-intensity acoustic pressure pulsations and propagates along the pipeline, causing vibration of structural components such as steam dryers and even high-cycle fatigue failure.

[0003] The existing Chinese patent with publication number CN206946957U discloses a piping system for preventing the release of radioactive materials from a pressurized water reactor, including a containment shell and an integrated reactor. Two main steam pipelines are provided at the secondary side outlet of the steam generator, and anti-bypass isolation valves are provided on the main steam pipelines. The bypass isolation valve is located on the inner side of the containment shell. The ends of the two main steam pipelines are connected and merged to form a steam bus. A temperature sensor is provided in the steam generator, and the temperature sensor is electrically connected to a controller. The actuator of the bypass isolation valve is electrically connected to the controller.

[0004] The domestic advanced pressurized water reactor AP1000 and the National Nuclear Power Plant No. 1 are both equipped with bypass piping. When the vortex shedding frequency at the bypass piping and the main pipeline tee is coupled with the acoustic cavity frequency of the piping system to cause "acoustic resonance", strong vibrations will be generated on the pipeline, endangering the safe operation of the reactor. In order to understand the characteristics of acoustic resonance, it is necessary to measure the flow-induced vibration. However, hydrodynamic noise will greatly affect the dynamic pressure measurement, and the speed of sound is greatly affected by temperature.

[0005] The inventors believe that hydrodynamic noise will greatly affect dynamic pressure measurement. At the same time, since the speed of sound is greatly affected by temperature, it is necessary to design a reasonable test system to reduce hydrodynamic noise and improve the accuracy of measurement data, and to stably control the temperature, providing technical reserves for the safe operation of advanced pressurized water reactors. Summary of the invention

[0006] In view of the defects in the prior art, the object of the present invention is to provide a hot test system for measuring the flow-induced acoustic resonance of a pipe system under high-temperature and high-pressure water medium.

[0007] According to the present invention, a hot test system for measuring flow-induced acoustic resonance of a pipe system under high-temperature and high-pressure water medium comprises: a main pipe system and a bypass system, wherein the main pipe system and the bypass system are connected; the main pipe system comprises a heater, a pump, a buffer tank and a flow meter which are connected in sequence through a connecting pipe to form a loop; the bypass system comprises a bypass measurement pipeline, a dynamic pressure measurement system and a return water system; one end of the bypass measurement pipeline is connected to the connecting pipeline between the flow meter and the heater, and the other end is connected to the return water system; one end of the return water system away from the bypass measurement pipeline is connected to the connecting pipeline between the flow meter and the heater, and is located downstream of the connection port between the bypass measurement pipeline and the connecting pipeline; the dynamic pressure measurement system is used to measure the bypass measurement pipeline.

[0008] Preferably, a thermometer and a pressure gauge are provided between the buffer tank and the flow meter.

[0009] Preferably, the buffer tank comprises a baffle structure; and the distance between the buffer tank and the pump is greater than times the diameter of the connecting pipeline.

[0010] Preferably, an exhaust pipeline is provided on the buffer tank, and an exhaust valve is provided on the exhaust pipeline.

[0011] Preferably, the dynamic pressure measurement system comprises a dynamic pressure sensor, a signal amplifier and a signal acquisition system which are connected in sequence; the dynamic pressure sensor is arranged on a side of the bypass measurement pipeline away from the main pipeline system.

[0012] Preferably, the dynamic pressure sensor comprises a pressure-charge conversion sensor; and the distance between the dynamic pressure sensor and the signal amplifier is greater than or equal to 0.5 m and less than or equal to 1 m.

[0013] Preferably, the water return system comprises a water return pipeline, and a stop valve is provided on the water return pipeline.

[0014] Preferably, the main pipeline system further comprises a fixing support structure, and the fixing support structure is respectively arranged on a side of the buffer tank away from the pump and around a connection port of the connecting pipeline and the bypass measurement pipeline.

[0015] Preferably, the flowing medium in the connecting pipeline includes water, and the temperature of the flowing medium is higher than 200°C.

[0016] Preferably, a heat insulating layer is provided on the bypass system.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention helps to improve the accuracy of temperature control, reduce the periodic pressure oscillation input of the pump, increase the strength of the measurement signal, and simulate the real working environment, thereby helping to improve the validity and accuracy of the measurement data of the test system through the coordinated use of the main pipeline system and the bypass system.

[0019] 2. The present invention helps to improve the signal strength measured in the water medium by arranging a signal amplifier in the dynamic pressure measurement system, thereby helping to improve the effectiveness and accuracy of the measurement data of the test system.

[0020] 3. The present invention helps to reduce the influence of external environmental vibration sources by arranging a fixed support structure on the pipeline, thereby helping to improve the accuracy of the measurement data of the test system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0022] Figure 1 This is a schematic diagram of the overall structure of the hot test system for measuring the flow-induced acoustic resonance of the piping system under high temperature and high pressure water medium;

[0023] Figure 2 This is a cross-sectional schematic diagram of the buffer tank structure.

[0024] As shown in the figure:

[0025] Pump 1 Buffer tank 2 Fixed support structure 3

[0026] Thermometer 4 Pressure gauge 5 Flow meter 6

[0027] Control valve 7 Bypass measuring line 8 Dynamic pressure sensor 9

[0028] Signal amplifier 10 Signal acquisition system 11 Water return pipeline 12

[0029] Heater 13 Stop valve 14 DETAILED DESCRIPTION

[0030] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0031] like Figure 1As shown, a hot test system for measuring flow-induced acoustic resonance of a pipe system under high-temperature and high-pressure water medium provided according to the present invention includes: a main pipe system and a bypass system, and the main pipe system and the bypass system are connected. The main pipe system includes a heater 13, a pump 1, a buffer tank 2 and a flow meter 6, which are connected in sequence through a connecting pipe to form a loop. The bypass system includes a bypass measurement pipeline 8, a dynamic pressure measurement system and a return water system. One end of the bypass measurement pipeline 8 is connected to the connecting pipeline between the flow meter 6 and the heater 13, and the other end is connected to the return water system; the end of the return water system away from the bypass measurement pipeline 8 is connected to the connecting pipeline between the flow meter 6 and the heater 13, and is located downstream of the connection port between the bypass measurement pipeline 8 and the connecting pipeline. The dynamic pressure measurement system is used to measure the bypass measurement pipeline 8.

[0032] When the test system is started, the pump 1 on the main pipeline system guides the flow medium heated by the heater 13 into the buffer tank 2. Under the action of the buffer tank 2, the flow medium flows through the flow meter 6 and then flows into the bypass system. Then, it flows through the bypass measurement pipeline 8 and the return water system and flows into the main pipeline system. The flow medium flows to the heater 13 to form a loop. At this time, the dynamic pressure measurement system set on the bypass measurement pipeline 8 performs measurement work to obtain test data.

[0033] In the test system, the flowing medium in the connecting pipe includes water, and the temperature of the flowing medium is higher than 200°C under the action of the heater 13, so as to achieve the test effect. A heat insulation layer is provided on the bypass system. Preferably, the bypass system needs to be insulated with multiple layers, with the insulation layer being greater than or equal to 3 layers, and each layer being not less than 2 cm, so as to reduce the influence of the temperature difference on the measurement, thereby ensuring the accurate measurement of the test data.

[0034] The main pipeline system includes a heater 13, a pump 1, a buffer tank 2 and a flow meter 6 which are connected in sequence through connecting pipes to form a loop. A control valve 7 is provided on the side of the flow meter 6 away from the buffer tank 2, and the control valve 7 is used to control the opening or closing of the test loop.

[0035] like Figure 2 As shown, the buffer tank 2 includes a baffle structure. Preferably, the internal structure of the buffer tank 2 is a multi-layer baffle structure. The buffer tank 2 plays a role in kinetic energy and pressure conversion. The baffle can increase the circuit resistance and weaken the periodic pressure fluctuations caused by the rotation of the pump blades layer by layer, thereby achieving the purpose of reducing the internal hydrodynamic noise.

[0036] Furthermore, the distance between the buffer tank 2 and the pump 1 is greater than 20 times the diameter of the connecting pipeline, thereby ensuring the working efficiency of the buffer tank 2 and further improving the accuracy of the test system.

[0037] Furthermore, an exhaust pipeline is provided on the buffer tank 2, and an exhaust valve is provided on the exhaust pipeline. The exhaust pipeline is installed on the upper side of the buffer tank and is used to exhaust the gas in the main pipeline system loop during the test startup. The acoustic resonance characteristics of gas are completely different from those of water. In order to prevent gas vibration interference, the loop needs to be exhausted.

[0038] A thermometer 4 and a pressure gauge 5 are provided between the buffer tank 2 and the flow meter 6. The thermometer 4 is used to measure the temperature of the flowing medium in the connecting pipeline to ensure that the flowing medium reaches the required temperature of the test, thereby ensuring the accuracy of the test. The pressure gauge 5 measures the pressure in the connecting pipeline to ensure that the test system reaches the required pressure of the test, thereby ensuring the accuracy of the test.

[0039] The bypass system includes a bypass measurement pipeline 8, a dynamic pressure measurement system and a return water system. One end of the bypass measurement pipeline 8 is connected to the connecting pipeline between the flow meter 6 and the heater 13, and the other end is connected to the return water system; the end of the return water system away from the bypass measurement pipeline 8 is connected to the connecting pipeline between the flow meter 6 and the heater 13, and is located downstream of the connection between the bypass measurement pipeline 8 and the connecting pipeline. The dynamic pressure measurement system is used to measure the bypass system.

[0040] The bypass measurement pipeline 8 is a pipeline that is scaled and modeled according to actual engineering requirements, thereby ensuring the validity of the measurement data of the test system.

[0041] The dynamic pressure measurement system comprises a dynamic pressure sensor 9, a signal amplifier 10 and a signal acquisition system 11 connected in sequence. The dynamic pressure sensor 9 is arranged on a side of the bypass measurement pipeline 8 away from the main pipeline system.

[0042] Furthermore, the dynamic pressure sensor 9 includes a pressure-charge conversion sensor. Since the temperature of the flowing medium is higher than 200°C, the dynamic pressure sensor 9 includes electronic components that can withstand high temperatures. The distance between the dynamic pressure sensor 9 and the signal amplifier 10 is greater than or equal to 0.5m and less than or equal to 1m. Due to the introduction of the vibration source of the test system, the introduction of the external environment vibration source and the phenomenon that the measured signal strength is weak under the water medium, the dynamic pressure measurement system strengthens the effective information of the signal and improves the signal-to-noise ratio by introducing the signal amplifier 10. The distance between the signal amplifier 10 and the dynamic pressure sensor 9 is less than or equal to 1m to reduce the impact of noise; the distance between the signal amplifier 10 and the dynamic pressure sensor 9 is greater than or equal to 0.5m to prevent high temperature from burning the signal line and the amplifier.

[0043] The return water system includes a return water pipeline 12, which is used to control the temperature of the test system. A stop valve 14 is provided on the return water pipeline 12, and the test system can be quickly heated up or cooled down by opening or closing the stop valve 14.

[0044] The main pipeline system also includes a fixed support structure 3, which is respectively arranged on the connecting pipeline on the side of the buffer tank 2 away from the pump 1, on the connecting pipelines on both sides of the connecting port of the connecting pipeline and the bypass measurement pipeline 8, and on the side of the bypass measurement pipeline 8 close to the connecting port of the connecting pipeline and the bypass measurement pipeline 8. The fixed support structure 3 is used to reduce the fluctuation introduced into the non-test system, reduce the influence of the external environmental vibration source, and ensure the validity and accuracy of the test system measurement data.

[0045] The hot test system for measuring flow-induced acoustic resonance of piping systems under high-temperature and high-pressure water media sets up modular and scaled pipelines according to real engineering requirements, reduces hydrodynamic noise and improves the accuracy of measurement data, and stably controls the temperature, providing technical reserves for the safe operation of advanced pressurized water reactors.

[0046] How it works

[0047] When the test system is started, the pump 1 on the main pipeline system guides the flow medium heated by the heater 13 into the buffer tank 2. Under the action of the buffer tank 2, the flow medium flows through the flow meter 6 and then flows into the bypass system. Then, it flows through the bypass measurement pipeline 8 and the return water system and flows into the main pipeline system. The flow medium flows to the heater 13 to form a loop. At this time, the dynamic pressure measurement system set on the bypass measurement pipeline 8 performs measurement work to obtain test data.

[0048] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0049] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A hot test system for measuring flow-induced acoustic resonance of a pipe system under high temperature and high pressure water medium, characterized in that: include: A main pipeline system and a bypass system, wherein the main pipeline system and the bypass system are in communication; The main pipeline system comprises a heater (13), a pump (1), a buffer tank (2) and a flow meter (6) which are sequentially connected through connecting pipelines to form a loop; The bypass system comprises a bypass measurement pipeline (8), a dynamic pressure measurement system and a water return system; One end of the bypass measurement pipeline (8) is in communication with the connecting pipeline between the flow meter (6) and the heater (13), and the other end is in communication with the return water system; One end of the return water system away from the bypass measuring pipeline (8) is in communication with the connecting pipeline between the flow meter (6) and the heater (13), and is located downstream of the connection port between the bypass measuring pipeline (8) and the connecting pipeline; The dynamic pressure measurement system is used to measure the bypass measurement pipeline (8); The buffer tank (2) comprises a baffle structure; The distance between the buffer tank (2) and the pump (1) is greater than 20 times the diameter of the connecting pipeline.

2. The hot test system for measuring flow-induced acoustic resonance of piping under high-temperature and high-pressure water medium according to claim 1, characterized in that: A thermometer (4) and a pressure gauge (5) are provided between the buffer tank (2) and the flow meter (6).

3. The hot test system for measuring flow-induced acoustic resonance of piping under high temperature and high pressure water medium according to claim 1, characterized in that: The buffer tank (2) is provided with an exhaust pipeline, and the exhaust pipeline is provided with an exhaust valve.

4. The hot test system for measuring flow-induced acoustic resonance of a pipe system under high temperature and high pressure water medium according to claim 1, characterized in that: The dynamic pressure measurement system comprises a dynamic pressure sensor (9), a signal amplifier (10) and a signal acquisition system (11) which are connected in sequence; The dynamic pressure sensor (9) is arranged on a side of the bypass measurement pipeline (8) away from the main pipeline system.

5. The hot test system for measuring flow-induced acoustic resonance of piping under high-temperature and high-pressure water medium according to claim 4, characterized in that: The dynamic pressure sensor (9) comprises a pressure-charge conversion sensor; The distance between the dynamic pressure sensor (9) and the signal amplifier (10) is greater than or equal to 0.5 m and less than or equal to 1 m.

6. The hot test system for measuring flow-induced acoustic resonance of a pipe system under high temperature and high pressure water medium according to claim 1, characterized in that: The water return system comprises a water return pipeline (12), and a stop valve (14) is arranged on the water return pipeline (12).

7. The hot test system for measuring flow-induced acoustic resonance of piping under high-temperature and high-pressure water medium according to claim 1, characterized in that: The main pipeline system further comprises a fixed support structure (3), wherein the fixed support structure (3) is respectively arranged on a side of the buffer tank (2) away from the pump (1) and around a connection port between the connecting pipeline and the bypass measurement pipeline (8).

8. The hot test system for measuring flow-induced acoustic resonance of piping under high-temperature and high-pressure water medium according to claim 1, characterized in that: The flowing medium in the connecting pipeline includes water, and the temperature of the flowing medium is higher than 200°C.

9. The hot test system for measuring flow-induced acoustic resonance of a pipe system under high temperature and high pressure water medium according to claim 1, characterized in that: A heat insulating layer is arranged on the bypass system.

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