Device and method for determining pressure relief blow entrainment characteristics

Abstract

The invention belongs to the technical field of nuclear reactors, and particularly relates to a device and a method for determining pressure relief blow entrainment characteristics. The device comprises an inlet gas supply system, an inlet main pipeline simulation section, an outlet main pipeline simulation section, a T-shaped pipe and a blow-off pipe simulation section, the inlet gas supply system is connected with the first end of the T-shaped main pipe through the inlet main pipe simulation section; the second end of the T-shaped main pipe and the outlet of the branch pipe are respectively connected with one end of the outlet main pipe simulation section and one end of the blow-off pipe simulation section; the vertical section of the blow-off pipe simulation section is used for simulating the potential difference between a reactor prototype site pressure relief valve and a main pipeline; the inlet main pipeline simulation section, the outlet main pipeline simulation section, the T-shaped pipe and the blow-off pipe simulation section are all made of transparent materials. According to the embodiment of the invention, the entrainment characteristics of the liquid drops discharged under pressure relief under different conditions of a loss of water accident can be obtained, a solid foundation is laid for research and development of an advanced nuclear reactor system, and the research and development process of the advanced nuclear reactor system is effectively promoted.

Description

Technical Field

[0001] The present application belongs to the field of nuclear reactor technology, and specifically relates to a device and method for determining entrainment characteristics of pressure relief blowdown. Background Art

[0002] Third-generation advanced nuclear reactors use passive technologies to address design basis accidents such as loss of coolant (LOC) and non-LOC. When a LOC occurs, the passive system relies on gravity, pressurized gas drive force, and other methods that do not rely on the power system to inject water into the reactor core to protect the reactor safety. Because the driving force for gravity-based passive water injection is relatively weak, the main coolant system is generally depressurized in the later stages of the accident to increase the gravity injection flow rate. Opening the pressure relief valve to discharge steam from the main coolant system will entrain some droplets in the main pipeline, reducing the water capacity of the main coolant system and compromising the safety of the reactor core. Therefore, determining the droplet entrainment characteristics of pressure relief spraying under different conditions during a LOC accident has become an urgent problem to be solved. Summary of the Invention

[0003] The purpose of this application is to provide a method for determining the entrainment characteristics of pressure relief spraying, so as to solve the problem in the prior art of how to obtain the droplet entrainment characteristics of pressure relief spraying under different conditions under a loss of coolant accident.

[0004] Technical solution to achieve the purpose of this application:

[0005] A first aspect of an embodiment of the present application provides a device for determining entrainment characteristics of a pressure relief blowdown, the device comprising: an inlet gas supply system, an inlet main pipeline simulation section, an outlet main pipeline simulation section, a T-tube, and a blowdown pipe simulation section;

[0006] The inlet gas supply system is connected to the first end of the T-tube main pipe through the inlet main pipe simulation section; the second end of the T-tube main pipe and the outlet of the branch pipe are connected to the outlet main pipe simulation section and one end of the blowdown pipe simulation section respectively; the vertical section of the blowdown pipe simulation section is used to simulate the level difference between the reactor prototype on-site pressure relief valve and the main pipe;

[0007] The inlet main pipeline simulation section, outlet main pipeline simulation section, T-tube and blowpipe simulation section are all made of transparent materials.

[0008] Optionally, the device further comprises: a pressure relief valve and a droplet collection and measurement device;

[0009] The other end of the simulated section of the blowpipe is connected to the droplet collection and measurement device via a pressure relief valve.

[0010] Optionally, the connection mode between the T-tube and the inlet main pipeline simulation section and the outlet main pipeline simulation section is movable and adjustable, so that the branch pipes of the T-tube can be adjusted to any angle in the horizontal and vertical directions.

[0011] Optionally, the T-tube and the blowdown pipe simulation section are connected in a flexible manner.

[0012] Optionally, the inlet main pipe simulation section and the outlet pipe simulation section meet the requirements of entrainment simulation, and simulate with equal flow rate, equal relative liquid level height, and equal Froude number.

[0013] Optionally, the main pipe of the T-tube meets the requirements of the main pipe entrainment simulation, with constant flow rate, constant relative liquid level height, and constant Froude number simulation.

[0014] Optionally, the inlet main pipeline simulation section, the outlet main pipeline simulation section, the T-tube and the blowpipe simulation section are all made of high temperature and high pressure resistant transparent material.

[0015] A second aspect of the embodiments of the present application provides a method for determining entrainment characteristics of pressure relief spraying, which is applicable to any one of the devices for determining entrainment characteristics of pressure relief spraying provided in the first aspect of the embodiments of the present application; the method comprises:

[0016] Inject water into the simulated section of the inlet main pipe, the T-tube and the simulated section of the outlet main pipe to make the liquid level meet the requirement of equal relative liquid level height;

[0017] Control the steam flow rate of the inlet gas supply system to study the pressure relief, blowdown and entrainment characteristics of different inlet steam flow rates of the main pipe section; and / or control the outlet steam flow rate of the outlet main pipe simulation section to study the pressure relief, blowdown and entrainment characteristics of different outlet steam flow rates.

[0018] Optionally, when the device further comprises: a pressure relief valve and a droplet collection and measurement device, the method further comprises:

[0019] Control the opening time of the pressure relief valve and study the influence of the pressure relief valve opening characteristics on the pressure relief blowdown entrainment characteristics;

[0020] The droplet collection and measurement device is used to collect and measure the droplet flow rate entrained from the main pipeline after the pressure relief valve is opened, and the entrainment characteristics are studied.

[0021] Optionally, the method further includes:

[0022] The branch pipes of the T-type pipe were changed to study the entrainment characteristics of pressure relief blowdown under different ratios of branch pipe diameter to main pipe diameter.

[0023] The beneficial technical effects of this application are:

[0024] The embodiment of the present application provides a device for determining the entrainment characteristics of a pressure relief blowdown, comprising: an inlet gas supply system, an inlet main pipeline simulation section, an outlet main pipeline simulation section, a T-tube, and a blowdown pipe simulation section; the inlet gas supply system is connected to the first end of the T-tube main pipe via the inlet main pipeline simulation section; the second end of the T-tube main pipe and the outlet of the branch pipe are connected to the outlet main pipeline simulation section and one end of the blowdown pipe simulation section, respectively; the vertical section of the blowdown pipe simulation section is used to simulate the level difference between the prototype reactor's on-site pressure relief valve and the main pipeline; the inlet main pipeline simulation section, the outlet main pipeline simulation section, the T-tube, and the blowdown pipe simulation section are all made of transparent materials. The embodiment of the present application can obtain the droplet entrainment characteristics of the pressure relief blowdown under different conditions under a loss of coolant accident. The research results can verify and optimize the design of the reactor's pressure relief system, lay a solid foundation for the research and development of advanced nuclear reactor systems, and effectively promote the research and development process of advanced nuclear reactor systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic structural diagram of a device for determining the entrainment characteristics of pressure relief spraying provided in an embodiment of the present application.

[0026] In the picture:

[0027] 1-Inlet gas supply system; 2-Inlet main pipeline simulation section; 3-Outlet main pipeline simulation section; 4-T-type pipe; 5-Blow pipe simulation section; 6-Pressure relief valve; 7-Droplet collection and measurement device. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the embodiments described below are only part of the embodiments of the present application, not all of them. Based on the embodiments recorded in this application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0029] See also Figure 1 , which is a structural schematic diagram of a device for determining the pressure relief spraying entrainment characteristics provided in an embodiment of the present application.

[0030] An embodiment of the present application provides a device for determining entrainment characteristics of pressure relief blowdown, comprising: an inlet gas supply system 1, an inlet main pipeline simulation section 2, an outlet main pipeline simulation section 3, a T-tube 4, and a blowdown pipe simulation section 5;

[0031] The inlet gas supply system 1 is connected to the first end of the main pipe of the T-tube 4 via the simulated inlet main pipe section 2. The second end of the main pipe of the T-tube 4 and the outlet of the branch pipe are respectively connected to the simulated outlet main pipe section 3 and one end of the blowdown pipe simulated section 5. The vertical section of the blowdown pipe simulated section 5 is used to simulate the level difference between the on-site pressure relief valve of the reactor prototype and the main pipe.

[0032] The inlet main pipeline simulation section 2, the outlet main pipeline simulation section 3, the T-tube 4 and the blowdown pipe simulation section 5 are all made of transparent materials.

[0033] In the embodiment of the present application, the inlet gas supply system 1 has the function of supplying gas at different temperatures, different pressures, and different flow rates, simulating the steam from the reactor pressure vessel in the main pipeline during a loss of coolant accident, and the generated gas enters the inlet main pipeline simulation section 2 through the connecting pipe. The upstream of the inlet main pipeline simulation section 2 is connected to the inlet gas supply system 1, and an on-off isolation valve can be designed in the middle. The downstream is connected to one end of the main pipe of the T-tube 4. The other end of the main pipe of the T-tube 4 is connected to the outlet main pipeline simulation section 3. An on-off isolation valve can be designed for the outlet connected to the outlet main pipeline simulation section 3. The vertical section of the blowdown pipe simulation section 5 adopts different lengths to simulate the position difference between the on-site pressure relief valve and the main pipeline of the prototype reactor. The inlet main pipeline simulation section 2, the outlet main pipeline simulation section 3, the T-tube 4 and the blowdown pipe simulation section 5 are all made of transparent materials, which can visually observe the changing characteristics of the gas-liquid interface in the main pipeline, the entrainment characteristics of the T-tube 4, and the distribution characteristics of the droplets in the blowdown pipe.

[0034] In actual application, before the test, the isolation valves of the inlet main pipeline simulation section 2 and the outlet main pipeline simulation section 3 are closed, and water is injected into the inlet main pipeline simulation section 2, T-tube 4 and outlet main pipeline simulation section 3 so that the liquid level meets the requirements of equal relative liquid level height. The liquid level height is changed to realize the study of the entrainment characteristics under different liquid level conditions of the main pipe section. The steam flow rate of the inlet gas supply system 1 is controlled to realize the study of the pressure relief spraying entrainment characteristics of the main pipe section with different inlet steam flow rates. The outlet steam flow rate of the outlet main pipeline simulation section 3 is controlled to realize the study of the pressure relief spraying entrainment characteristics of different outlet steam flow rates. The pressure relief spraying entrainment characteristics under conditions such as different inlet steam flow rates, different outlet steam flow rates, and different initial liquid level heights can be studied.

[0035] In specific implementation, the inlet main pipeline simulation section 2, the outlet main pipeline simulation section 3, the T-tube 4 and the blowpipe simulation section 5 can all be made of high temperature and high pressure resistant transparent materials, so that the distribution of entrainment in the blowpipe simulation section can be observed.

[0036] In some possible implementations of the embodiments of the present application, the device may further include: a pressure relief valve 6 and a droplet collection and measurement device 7;

[0037] The other end of the spray pipe simulation section 5 is connected to the droplet collection and measurement device 7 via a pressure relief valve 6.

[0038] It should be noted that the vertical section of the simulated blowdown pipe section 5 is of different lengths to simulate the level difference between the pressure relief valve and the main pipeline in the prototype reactor site. The level difference between the pressure relief valve 6 and the main pipeline has a significant impact on the pressure relief blowdown.

[0039] It can be understood that the inlet main pipeline simulation section 2, the outlet main pipeline simulation section 3, the T-tube 4 and the blowpipe simulation section 5 are made of high-temperature and high-pressure resistant transparent materials, which can visually observe the changing characteristics of the gas-liquid interface in the main pipeline during the opening process of the pressure relief valve, the entrainment characteristics of the T-tube 4, and the distribution characteristics of the droplets in the blowpipe simulation section 5.

[0040] In practice, the opening time of pressure relief valve 6 is adjustable. By designing the opening time, the opening characteristics of various pressure relief valves in prototype reactors, such as burst valves, pneumatic valves, and electric valves, are simulated to study the influence of the opening characteristics of pressure relief valve 6 on the entrainment characteristics of the pressure relief spray. A droplet collection and measurement device 7 collects and measures the droplet flow rate entrained from the main pipeline after pressure relief valve 6 is opened, thereby studying the entrainment characteristics.

[0041] In one example, the connection between the T-tube 4 and the inlet main pipeline simulation section 2 and the outlet main pipeline simulation section 3 is movable and adjustable, so that the branch pipes of the T-tube 4 can be adjusted to any angle in the horizontal and vertical directions.

[0042] In another example, the T-tube 4 and the blowdown pipe simulation section 5 can be flexibly connected to ensure that the blowdown flow at different inclination angles of the T-tube 4 can enter the blowdown pipe simulation section 5, and the pressure relief blowdown entrainment characteristics under different blowdown angles can be studied.

[0043] In some possible implementations of the embodiments of the present application, the inlet main pipeline simulation section 2 and the outlet pipeline simulation section 3 can meet the requirements of entrainment simulation, simulating equal flow rate, equal relative liquid level height, and equal Froude number.

[0044] In some possible implementations of the embodiments of the present application, the main pipe of the T-tube 4 can meet the requirements of the main pipeline entrainment simulation, such as constant flow rate, constant relative liquid level height, and constant Froude number simulation.

[0045] In one example, the main pipe of the T-tube 4 meets the requirements of the main pipe entrainment simulation, and simulates constant flow rate, constant relative liquid level height, and constant Froude number. The branch pipe sizes of the T-tube 4 can be designed to have different specifications, and the pressure relief spray entrainment characteristics under different branch pipe diameter and main pipe diameter ratio conditions can be studied.

[0046] The device embodiment of this application features a simple structure, mature manufacturing process, and low cost. It can be used to study the entrainment characteristics of the blowdown process during a loss of coolant accident under various conditions, including different initial states of the main pipeline, different core thermal parameters, different T-tube orientations, different riser pipeline parameters, and different pressure relief valve opening characteristics. The research results can verify and optimize the design of reactor pressure relief systems, laying a solid foundation for the development of advanced nuclear reactor systems and effectively promoting their research and development.

[0047] Based on the device for determining the entrainment characteristics of pressure relief spraying provided in the above embodiment, the embodiment of the present application also provides a method for determining the entrainment characteristics of pressure relief spraying, which is applied to any one of the devices for determining the entrainment characteristics of pressure relief spraying provided in the above embodiment.

[0048] An embodiment of the present application provides a method for determining entrainment characteristics of a pressure relief blowdown, including:

[0049] Step S101: injecting water into the inlet main pipe simulation section 2, the T-shaped pipe 4 and the outlet main pipe simulation section 3 so that the liquid levels meet the requirement of equal relative liquid level height;

[0050] Step S102: controlling the steam flow rate of the inlet gas supply system 1 to study the pressure relief, spraying and entrainment characteristics of different inlet steam flow rates of the main pipe section;

[0051] And / or, step S103: controlling the outlet steam flow rate of the outlet main pipeline simulation section 3 to realize the study of the pressure relief, spraying and entrainment characteristics of different outlet steam flow rates.

[0052] In some possible implementations of the embodiments of the present application, when the device further includes: a pressure relief valve 6 and a droplet collection and measurement device 7, the method may further include:

[0053] Control the opening time of the pressure relief valve 6 and study the influence of the opening characteristics of the pressure relief valve 6 on the entrainment characteristics of the pressure relief spray;

[0054] The droplet collection and measurement device 7 is used to collect and measure the droplet flow rate entrained from the main pipeline after the pressure relief valve 6 is opened, and the entrainment characteristics are studied.

[0055] In some possible implementations of the embodiments of the present application, the method may further include:

[0056] The branch pipes of T-type pipe 4 were changed to study the entrainment characteristics of pressure relief spraying under different ratios of branch pipe diameter to main pipe diameter.

[0057] The specific experimental methods can refer to the relevant instructions above and will not be repeated here.

[0058] The embodiments of the present application can obtain the droplet entrainment characteristics of pressure relief spraying under different conditions during a loss of coolant accident. The research results can verify and optimize the design of the reactor's pressure relief system, lay a solid foundation for the research and development of advanced nuclear reactor systems, and effectively promote the research and development process of advanced nuclear reactor systems.

[0059] The present application has been described in detail above with reference to the accompanying drawings and embodiments. However, the present application is not limited to the above embodiments. Various modifications can be made within the scope of knowledge possessed by a person skilled in the art without departing from the purpose of the present application. Any content not described in detail in the present application may be based on existing technologies.

Claims

1. A device for determining the entrainment characteristics of pressure relief spraying, characterized in that: The device comprises: an inlet gas supply system (1), an inlet main pipeline simulation section (2), an outlet main pipeline simulation section (3), a T-shaped pipe (4) and a blowdown pipe simulation section (5); The inlet gas supply system (1) is connected to the first end of the main pipe of the T-tube (4) via the inlet main pipe simulation section (2); the second end of the main pipe of the T-tube (4) and the outlet of the branch pipe are respectively connected to the outlet main pipe simulation section (3) and one end of the blowdown pipe simulation section (5); the vertical section of the blowdown pipe simulation section (5) is used to simulate the level difference between the on-site pressure relief valve of the reactor prototype and the main pipe; The inlet main pipeline simulation section (2), the outlet main pipeline simulation section (3), the T-shaped pipe (4) and the blowdown pipe simulation section (5) are all made of transparent materials.

2. The device for determining the entrainment characteristics of pressure relief spraying according to claim 1, characterized in that: The device further comprises: a pressure relief valve (6) and a droplet collection and measurement device (7); The other end of the spray pipe simulation section (5) is connected to the droplet collection and measurement device (7) via a pressure relief valve (6).

3. The device for determining the entrainment characteristics of pressure relief spraying according to claim 1 or 2, characterized in that: The connection mode between the T-shaped pipe (4) and the inlet main pipeline simulation section (2) and the outlet main pipeline simulation section (3) is movable and adjustable, so that the branch pipes of the T-shaped pipe (4) can be adjusted to any angle in the horizontal and vertical directions.

4. The device for determining the entrainment characteristics of pressure relief spraying according to claim 1 or 2, characterized in that: The T-shaped pipe (4) and the blowdown pipe simulation section (5) are connected in a flexible manner.

5. The device for determining the entrainment characteristics of pressure relief spraying according to claim 1 or 2, characterized in that: The inlet main pipe simulation section (2) and the outlet pipe simulation section (3) meet the requirements of entrainment simulation, and simulate constant flow rate, constant relative liquid level height, and constant Froude number.

6. The device for determining the entrainment characteristics of pressure relief spraying according to claim 1 or 2, characterized in that: The main pipe of the T-tube (4) meets the requirements of the main pipeline entrainment simulation, and simulates the flow rate, relative liquid level and Froude number.

7. The device for determining the entrainment characteristics of pressure relief spraying according to claim 1 or 2, characterized in that: The inlet main pipeline simulation section (2), the outlet main pipeline simulation section (3), the T-shaped pipe (4) and the blowdown pipe simulation section (5) are all made of high-temperature and high-pressure resistant transparent material.

8. A method for determining the entrainment characteristics of a pressure relief blowdown, characterized in that: The device for determining the entrainment characteristics of pressure relief spraying as described in any one of claims 1 to 7; the method comprising: Injecting water into the inlet main pipe simulation section (2), the T-shaped pipe (4) and the outlet main pipe simulation section (3) so that the liquid levels meet the requirements of equal relative liquid level height; The steam flow rate of the inlet gas supply system (1) is controlled to realize the pressure relief, spraying and entrainment characteristics research of different inlet steam flow rates of the main pipe section; and / or the outlet steam flow rate of the outlet main pipe simulation section (3) is controlled to realize the pressure relief, spraying and entrainment characteristics research of different outlet steam flow rates.

9. The method for determining the entrainment characteristics of pressure relief spraying according to claim 8, characterized in that: When the device further comprises: a pressure relief valve (6) and a droplet collection and measurement device (7), the method further comprises: Control the opening time of the pressure relief valve (6) and study the influence of the opening characteristics of the pressure relief valve (6) on the entrainment characteristics of the pressure relief spray; The droplet collection and measurement device (7) is used to collect and measure the droplet flow rate entrained from the main pipeline after the pressure relief valve (6) is opened, and the entrainment characteristic law is studied.

10. The method for determining the entrainment characteristics of pressure relief spraying according to claim 8, characterized in that: The method further comprises: The branch pipes of the T-shaped pipe (4) are changed to study the pressure relief spray entrainment characteristics under different branch pipe diameter and main pipe diameter ratio conditions.

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