A power control system and method for a heat pipe cooling reactor

Abstract

The present invention discloses a power control system and method for a heat pipe cooling reactor, the system comprising: a reactor core, a heat pipe heat exchanger, a bent heat pipe and a pneumatic rotating part, wherein the heat pipe heat exchanger is arranged on the left side of the reactor core through a bent heat pipe, a working medium is retained in the bent heat pipe, and the pneumatic rotating part is respectively connected to the reactor core and the heat pipe heat exchanger. The present invention can be used for heat pipe reactor nuclear power control, can make the heat pipe reactor nuclear power more matched with the power required by the load, and improve the efficiency of the heat pipe reactor.

Description

Technical Field

[0001] The invention relates to the technical field of heat pipe reactor control system design, and in particular to a power control system and method for a heat pipe cooled reactor. Background Art

[0002] Looking into the future, the environment explored by humans is becoming more and more complex, and they are turning more to the development and research of unknown areas. Heat pipe reactors have core advantages such as high inherent safety, simple operating characteristics, easy modularization and expansion, and good transportation characteristics. In general, heat pipe cooled reactors have broad application prospects in deep space exploration and propulsion, land-based nuclear power sources, deep-sea submarine exploration and other scenarios, and may become one of the disruptive technologies that change the future nuclear power landscape. However, in the existing heat pipe reactor control system design, the power regulation of heat pipe reactors is relatively simple, and it is urgent to expand the control system design of heat pipe reactors to improve the dynamic influence ability of output power regulation of nuclear power units and the mobility of the system. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a power control system and method for a heat pipe cooled reactor to solve the technical problem that the output power of the compressor cannot be controlled by changing the flow rate of the working fluid entering the turbine compressor, and energy conversion efficiency and rapid maneuverability cannot be taken into account at the same time.

[0004] On the one hand, to achieve the above-mentioned purpose, the present invention provides a power control system for a heat pipe cooled reactor, comprising:

[0005] A reactor core, a heat pipe heat exchanger, a bent heat pipe and a pneumatic rotating part, wherein the heat pipe heat exchanger is arranged on the left side of the reactor core through the bent heat pipe, a working medium is retained in the bent heat pipe, and the pneumatic rotating part is connected to the reactor core and the heat pipe heat exchanger respectively;

[0006] The pneumatic rotating part includes a rotating main shaft, a rotating retainer, a water inlet and an air hole. The water inlet and the air hole are connected through a pipeline. The rotating retainer is respectively fixedly connected to the heat pipe heat exchanger and the reactor core, and the rotating main shaft is fixedly connected to the rotating retainer.

[0007] Preferably, the reactor core comprises a core metal matrix, and a plurality of fuel rods are arranged in the core metal matrix.

[0008] Preferably, the constituent material of the core metal matrix is ​​stainless steel, and the constituent material of the fuel rods is uranium dioxide.

[0009] Preferably, one end of the curved heat pipe is inserted into the heat pipe heat exchanger, and the other end is inserted into the reactor core, and the portion of the curved heat pipe located between the reactor core and the heat pipe heat exchanger is coated with a thermal insulation layer.

[0010] Preferably, the bent heat pipe is provided with a bending angle at a condensation end of the heat pipe, and the bending angle is determined according to the power of the heat pipe stack.

[0011] On the other hand, in order to achieve the above object, a power control method for a heat pipe cooling reactor is also provided, comprising:

[0012] Power control during the startup phase: The flow rate of the working fluid entering the heat pipe heat exchanger is adjusted based on the inverse proportional relationship between the temperature deviation between the hot and cold ends of the heat pipe reactor and the flow rate of the working fluid entering the heat pipe heat exchanger;

[0013] Power control during the working phase: adjust the heat transfer performance of the heat pipe by adjusting the relationship between the expected power and the actual output power;

[0014] Power control during shutdown: using residual heat to start the pneumatic rotating part until the maximum pressure drop is generated, and then controlling the flow of working fluid into the heat pipe heat exchanger and the nuclear reaction rate of the reactor;

[0015] The power control in the startup phase includes a transition phase from the solid or liquid inside the wick to a free molecule state, a diffusion phase of the free molecule state to the entire heat pipe, and a power fine-tuning phase.

[0016] Preferably, the power control method in the startup phase includes:

[0017] Get the temperature deviation between the hot and cold ends of the heat pipe reactor;

[0018] The temperature deviation between the hot and cold ends of the heat pipe reactor is transmitted to the controller, the control quantity of the heat pipe reactor control object is calculated, and the required flow rate of the working fluid entering the heat pipe heat exchanger is calculated based on the temperature deviation between the hot and cold ends of the heat pipe reactor;

[0019] By real-time detection of the actual output power, the deviation between the actual output power and the expected output power is obtained. When the deviation is less than a first preset value, the power fine-tuning stage is entered. At this time, the flow rate of the working fluid entering the heat pipe exchanger is stopped, and the power of the reactor is adjusted using the pneumatic rotating part.

[0020] Preferably, the power control method in the working phase includes:

[0021] Power adjustment is performed by determining the absolute value of the deviation percentage between the expected adjustment power and the actual output power, wherein the deviation percentage is the ratio of the difference between the expected adjustment power and the actual output power to the actual output power;

[0022] Among them, if the absolute value of the deviation percentage is greater than the second preset value or exceeds the preset range, the actual output power is changed by starting the pneumatic rotation system of the heat pipe reactor to change the heat transfer performance of the heat pipe and controlling the flow rate of the working fluid entering the heat pipe heat exchanger. At this time, the sum of the weights of rotating the heat pipe reactor to change the heat transfer performance of the heat pipe and controlling the flow rate of the working fluid entering the heat pipe heat exchanger is 1; if the absolute value of the deviation percentage is less than the second preset value or lower than the preset range, the pneumatic rotation system of the heat pipe reactor is used to change the heat transfer performance of the heat pipe, and fine-tune the actual output power to continuously approach the expected adjustment power until the actual output power reaches an acceptable range. At this time, the weight of rotating the heat pipe reactor to change the heat transfer performance of the heat pipe is 1.

[0023] Preferably, the power control method in the shutdown phase includes:

[0024] The residual heat is used to start the pneumatic rotating part of the heat pipe reactor until the maximum pressure drop is generated, and then the flow rate of the working fluid entering the heat pipe heat exchanger is gradually reduced and the nuclear reaction rate of the normal control reactor is gradually reduced.

[0025] Compared with the prior art, the present invention has the following advantages and technical effects:

[0026] The present invention can be used for heat pipe reactor nuclear power control, can make the heat pipe reactor nuclear power more matched with the power required by the load, and improve the efficiency of the heat pipe reactor; can be used for rapid startup and rapid shutdown of the heat pipe reactor, and improve the mobility of the reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 This is a schematic diagram of the structure of a power control system for a heat pipe cooling reactor according to an embodiment of the present invention;

[0029] Figure 2 A control principle diagram of starting a heat pipe reactor according to an embodiment of the present invention;

[0030] Figure 3 This is a control principle diagram of the heat pipe reactor nuclear power according to an embodiment of the present invention;

[0031] Among them, 1. rotating main shaft; 2. rotating retainer; 3. heat pipe heat exchanger; 4. bent heat pipe; 5. air hole; 6. reactor core; 7. fuel rod; 8. water inlet; 9. core metal matrix. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0033] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0034] The present invention proposes a power control system for a heat pipe cooling reactor, such as Figure 1 ,include:

[0035] Reactor core 6, heat pipe heat exchanger 3, bent heat pipe 4 and pneumatic rotating part, wherein the heat pipe heat exchanger 3 is arranged on the left side of the reactor core 6 through the bent heat pipe 4, the working medium is retained in the bent heat pipe 4, and the pneumatic rotating part is connected to the reactor core 6 and the heat pipe heat exchanger 3 respectively.

[0036] The reactor core 6 comprises a core metal matrix 9, and a plurality of fuel rods are arranged in the core metal matrix 9. The constituent material of the core metal matrix is ​​stainless steel, and the constituent material of the fuel rods is uranium dioxide.

[0037] Specifically, one end of the bent heat pipe 4 is inserted into the heat pipe heat exchanger 3, and the other end is inserted into the reactor core 6. The portion of the bent heat pipe 4 between the reactor core 6 and the heat pipe heat exchanger 3 is coated with a thermal insulation layer. The bent heat pipe 4 is bent at a certain angle at the condensation end of the heat pipe, and the actual bending position and angle should be determined according to the power regulation requirements of the heat pipe stack.

[0038] The pneumatic rotating part includes a rotating main shaft 1, a rotating retainer 2, a water inlet 8 and an air hole 5. The water inlet 8 and the air hole 5 are connected through a pipeline. The rotating retainer 2 is respectively fixedly connected to the heat pipe heat exchanger 3 and the reactor core 6. The rotating main shaft 1 is fixedly connected to the rotating retainer 2.

[0039] When it is necessary to rotate the rotating retainer 2 to change the heat transfer performance of the heat pipe and thus adjust the power of the heat pipe reactor, the water inlet 8 introduces water from the outside into the pipe inside the rotating retainer 2. After the water absorbs heat and evaporates into water vapor, it is discharged through the air hole 5 to obtain a rotational torque. The forward and reverse rotation of the rotating retainer can be achieved by controlling and coordinating the upper and lower air holes.

[0040] The present invention also proposes a power control method for a heat pipe cooling reactor, which specifically includes:

[0041] Power control method in the startup phase, power control method in the working phase and power control method in the shutdown phase;

[0042] Specifically, the control method of the startup phase includes three stages:

[0043] The first stage is the transition stage from the solid or liquid inside the liquid absorption core to the free molecular state. Considering that the change in power is approximately linear with the temperature change of the core and the matrix, a temperature sensor is used to detect the temperature, and the flow rate of the working fluid entering the heat pipe heat exchanger is adjusted according to the obtained temperature, so that the change in the flow rate of the working fluid entering the compressor is synchronously adapted to the operation state of the heat pipe. In this stage, due to the pressure drop generated by the heat pipe itself, the working fluid in the heat pipe is redistributed, so that the working fluid in the heat pipe is quickly heated and this stage is passed more quickly.

[0044] The second stage is the stage where the free molecules diffuse into the entire heat pipe. In this stage, the flow rate of the working fluid entering the heat pipe heat exchanger is changed and the pneumatic device is activated to make the condensed liquid return to the evaporation section faster and accelerate heat transfer.

[0045] The third stage is the power fine-tuning stage, during which the flow rate of the working fluid entering the heat pipe exchanger is stopped, and the power of the reactor is fine-tuned using a pneumatic device until it is within an acceptable power range.

[0046] The three stages are determined by the temperature change curve obtained by the temperature sensor and the actual output power to distinguish the three stages of different work, including:

[0047] The approximate linear change curve obtained by the temperature sensor in the initial stage is used to issue the working instructions for the first stage. When the temperature does not change significantly over time, it enters the second stage. At this time, the absolute value of the deviation percentage between the actual output power and the expected output power is used to judge the working stage. When this deviation percentage is less than the preset value or lower than the preset range, the startup stage enters the third stage, and the actual output power is fine-tuned until it finally reaches an acceptable range, and the startup stage is completed.

[0048] Power control methods during the startup phase, such as Figure 2 , specifically including the following steps:

[0049] S1, obtaining the temperature deviation of the hot and cold ends of the heat pipe reactor;

[0050] In this embodiment, the temperature deviation between the hot and cold ends of the heat pipe reactor is the difference between the hot end temperature of the heat pipe reactor and the cold end temperature of the heat pipe reactor, wherein the hot end temperature of the heat pipe reactor and the cold end temperature of the heat pipe reactor are both collected by temperature sensors.

[0051] S2, transmitting the temperature deviation signal of the hot and cold ends of the heat pipe reactor to the controller, and calculating the control quantity of the heat pipe reactor control object;

[0052] In this embodiment, the heat pipe reactor control objects include the heat pipe reactor pneumatic rotation system and the flow rate of the working fluid entering the heat pipe heat exchanger. The control quantity is obtained by comparing the temperature deviation of the hot and cold ends of the heat pipe reactor with the standard deviation of the hot and cold ends when the heat pipe reactor is operating normally. The standard deviation of the hot and cold ends when the heat pipe reactor is operating normally is measured by professionals.

[0053] S3, calculate the required flow rate of the working fluid entering the heat pipe heat exchanger based on the temperature deviation between the hot and cold ends of the heat pipe reactor to complete the first two stages of startup;

[0054] S4. Obtain the deviation between the actual output power and the expected output power. When the deviation is less than the first preset value, enter the third stage. At this time, stop changing the flow rate of the working fluid entering the heat pipe heat exchanger, and use the pneumatic device to fine-tune the power of the reactor, and finally reach an acceptable power range. Among them, the expected adjustment power is artificially set, which is the output power of the working fluid in the heat pipe heat exchanger to do work, and the expected adjustment power is the actual output power of the working fluid in the heat pipe heat exchanger to do work. The ultimate adjustment purpose is to make the expected adjustment power equal to the actual output power.

[0055] In actual work, the temperature deviation of the hot and cold ends of the heat pipe reactor is inversely proportional to the flow rate of the working fluid entering the heat pipe heat exchanger. The upper and lower limits are given according to the actual standard temperature deviation of the hot and cold ends of the heat pipe reactor. Within the range of the lower and upper limits, the flow rate of the working fluid entering the heat pipe heat exchanger is calculated based on the inverse proportional relationship from the temperature deviation of the hot and cold ends of the heat pipe reactor, thereby adjusting the flow rate of the working fluid entering the heat pipe heat exchanger.

[0056] A power change control method for a heat pipe reactor during the working phase, such as Figure 3 By judging the absolute value of the deviation percentage between the expected adjustment power and the actual output power, the adjustment mode is divided into two types, including:

[0057] Mode 1: When the absolute value of the deviation percentage is greater than the second preset value, the heat pipe reactor pneumatic rotation system is started to change the heat transfer performance of the heat pipe and the flow rate of the working fluid entering the heat pipe heat exchanger is controlled to quickly change the actual output power to be close to the expected adjustment power.

[0058] Mode 2: When the absolute value of the deviation percentage is less than the second preset value, the heat pipe reactor pneumatic rotation system is used to change the heat transfer performance of the heat pipe to fine-tune the actual output power to continuously approach the expected adjustment power until the actual output power reaches an acceptable range.

[0059] The above two modes determine the working mode by detecting the absolute value of the deviation percentage between the actual output power and the expected output power and the size relationship between the preset value or the preset range, specifically including:

[0060] When the absolute value of the deviation percentage is judged to be greater than the second preset value or exceeds the preset range, the rotating reactor is used to change the heat transfer performance of the heat pipe and the flow rate of the working fluid entering the heat pipe heat exchanger is combined to quickly change the actual output power close to the expected adjustment power. At this time, the sum of the weights of the rotating heat pipe reactor changing the heat transfer performance of the heat pipe and controlling the flow rate of the working fluid entering the heat pipe heat exchanger is 1. As the deviation percentage decreases, the weight of the flow rate of the working fluid entering the heat pipe heat exchanger gradually decreases, and the weight of the rotating reactor changing the heat transfer performance of the heat pipe gradually increases, but the sum of the weights of the rotating reactor changing the heat transfer performance of the heat pipe and controlling the flow rate of the working fluid entering the heat pipe heat exchanger remains unchanged at 1. The system is more stable in the process of transitioning from mode one to mode two.

[0061] If the absolute value of the deviation percentage is less than the second preset value or lower than the preset range, the second mode is adopted, and the heat transfer performance of the heat pipe is changed only by rotating the heat pipe reactor, so as to adjust the actual output power close to the expected adjustment power in a stable manner. At this time, the weight of the heat transfer performance of the heat pipe changed by rotating the heat pipe reactor is 1. The scheme of adjusting the heat transfer performance of the heat pipe back and forth is adopted to continuously make the actual output power close to the expected adjustment power or within an acceptable range.

[0062] The deviation percentage is equal to the ratio of the difference between the expected adjusted power and the actual output power to the actual output power.

[0063] The pneumatic rotation system of the heat pipe reactor is realized by changing the heat transfer performance of the heat pipe. Specifically, it changes the pressure drop of the condensation section of the heat pipe so that the liquid in the condensation section can flow back to the evaporation section more easily or more difficultly, thereby increasing or reducing the actual output power.

[0064] The power control method of a heat pipe reactor during shutdown phase specifically includes:

[0065] The heat pipe reactor structure is first rotated to achieve the maximum gravity pressure drop, so as to produce the greatest negative impact to weaken the heat transfer performance of the heat pipe and lay the foundation for the next startup of the heat pipe reactor. Then the flow rate of the working fluid entering the heat pipe heat exchanger is gradually reduced and the nuclear reaction rate of the normal control reactor is gradually reduced.

[0066] The present invention can be used for heat pipe reactor nuclear power control, can make the heat pipe reactor nuclear power more matched with the power required by the load, improve the efficiency of the heat pipe reactor, can be used for rapid start-up and rapid shutdown of the heat pipe reactor, and improve the mobility of the reactor.

[0067] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power control system for a heat pipe cooled reactor, characterized in that: include: A reactor core, a heat pipe heat exchanger, a bent heat pipe and a pneumatic rotating part, wherein the heat pipe heat exchanger is arranged on the left side of the reactor core through the bent heat pipe, a working medium is retained in the bent heat pipe, and the pneumatic rotating part is connected to the reactor core and the heat pipe heat exchanger respectively; The pneumatic rotating part includes a rotating main shaft, a rotating retainer, a water inlet and an air hole, the water inlet and the air hole are connected through a pipeline, the rotating retainer is respectively connected to the heat pipe heat exchanger and the reactor core, and the rotating main shaft is connected to the rotating retainer; The pneumatic rotating part is achieved by changing the heat transfer performance of the heat pipe, specifically by changing the pressure drop of the condensation section of the heat pipe so that the liquid in the condensation section can flow back to the evaporation section more easily or more difficultly, thereby increasing or reducing the actual output power.

2. The power control system for a heat pipe cooled reactor according to claim 1, characterized in that: The reactor core comprises a core metal matrix, and a plurality of fuel rods are arranged in the core metal matrix.

3. The power control system for a heat pipe cooled reactor according to claim 2, characterized in that: The constituent material of the core metal matrix is ​​stainless steel, and the constituent material of the fuel rod is uranium dioxide.

4. The power control system for a heat pipe cooled reactor according to claim 1, characterized in that: One end of the bent heat pipe is inserted into the heat pipe heat exchanger, and the other end is inserted into the reactor core. The portion of the bent heat pipe located between the reactor core and the heat pipe heat exchanger is coated with a thermal insulation layer.

5. The power control system for a heat pipe cooled reactor according to claim 4, characterized in that: The bent heat pipe is provided with a bending angle at the condensation end of the heat pipe, and the bending angle is determined according to the power of the heat pipe stack.

6. A power control method for a heat pipe cooled reactor, applied to a power control system for a heat pipe cooled reactor as claimed in any one of claims 1 to 5, characterized in that: include: Power control during the startup phase: The flow rate of the working fluid entering the heat pipe heat exchanger is adjusted based on the inverse proportional relationship between the temperature deviation between the hot and cold ends of the heat pipe reactor and the flow rate of the working fluid entering the heat pipe heat exchanger; Power control during the working phase: adjust the heat transfer performance of the heat pipe by adjusting the relationship between the expected power and the actual output power; Power control during shutdown: using residual heat to start the pneumatic rotating part until the maximum pressure drop is generated, and then controlling the flow of working fluid into the heat pipe heat exchanger and the nuclear reaction rate of the reactor; The power control in the startup phase includes a transition phase from the solid or liquid inside the wick to a free molecule state, a diffusion phase of the free molecule state to the entire heat pipe, and a power fine-tuning phase.

7. The power control method for a heat pipe cooled reactor according to claim 6, characterized in that: The power control method in the startup phase comprises: Get the temperature deviation between the hot and cold ends of the heat pipe reactor; The temperature deviation between the hot and cold ends of the heat pipe reactor is transmitted to the controller, the control quantity of the heat pipe reactor control object is calculated, and the required flow rate of the working fluid entering the heat pipe heat exchanger is calculated based on the temperature deviation between the hot and cold ends of the heat pipe reactor; By real-time detection of the actual output power, the deviation between the actual output power and the expected output power is obtained. When the deviation is less than a first preset value, the power fine-tuning stage is entered. At this time, the flow rate of the working fluid entering the heat pipe exchanger is stopped, and the power of the reactor is adjusted using the pneumatic rotating part.

8. The power control method for a heat pipe cooled reactor according to claim 6, characterized in that: The power control method in the working phase comprises: Power adjustment is performed by determining the absolute value of the deviation percentage between the expected adjustment power and the actual output power, wherein the deviation percentage is the ratio of the difference between the expected adjustment power and the actual output power to the actual output power; Among them, if the absolute value of the deviation percentage is greater than the second preset value or exceeds the preset range, the actual output power is changed by starting the pneumatic rotation system of the heat pipe reactor to change the heat transfer performance of the heat pipe and controlling the flow rate of the working fluid entering the heat pipe heat exchanger. At this time, the sum of the weights of rotating the heat pipe reactor to change the heat transfer performance of the heat pipe and controlling the flow rate of the working fluid entering the heat pipe heat exchanger is 1; if the absolute value of the deviation percentage is less than the second preset value or lower than the preset range, the pneumatic rotation system of the heat pipe reactor is used to change the heat transfer performance of the heat pipe, and fine-tune the actual output power to continuously approach the expected adjustment power until the actual output power reaches an acceptable range. At this time, the weight of rotating the heat pipe reactor to change the heat transfer performance of the heat pipe is 1.

9. The power control method for a heat pipe cooled reactor according to claim 6, characterized in that: The power control method in the shutdown phase comprises: The residual heat is used to start the pneumatic rotating part of the heat pipe reactor until the maximum pressure drop is generated, and then the flow rate of the working fluid entering the heat pipe heat exchanger is gradually reduced and the nuclear reaction rate of the normal control reactor is gradually reduced.

Images