Heat pipe starting calculation method and device and readable medium

Abstract

The invention provides a heat pipe starting calculation method, a simulation device and a readable medium. The heat pipe starting calculation method comprises the steps that a heat pipe thermal resistance network model is established, a steam cavity in the heat pipe thermal resistance network model is divided into a plurality of node control bodies, and the adjacent node control bodies are connected through thermal resistance; calculating the temperature of each node control body based on a thermal resistance network method; whether the temperature of the node control bodies exceeds the starting temperature of the heat pipe or not is judged one by one, if yes, the node control bodies are set to be in a starting state, and if not, the node control bodies are set to be in a non-starting state, and the heat resistance between the node control bodies in the non-starting state is modified to control the heat flow transfer process in the heat pipe.

Description

Technical Field

[0001] The present invention mainly relates to the field of nuclear power, and in particular to a heat pipe startup calculation method, a simulation device and a readable medium. Background Art

[0002] The heat pipe micro reactor is a unique small reactor system. Compared with traditional reactors, the heat pipe micro reactor is significantly reduced in power, size, weight, etc. It has the characteristics of factory prefabrication, transportable device, and self-regulation. The heat pipe is an important device in the heat pipe micro reactor, responsible for transferring heat from the core side to the heat exchanger side. The heat removal of the heat pipe is crucial for the normal operation of the reactor.

[0003] An important issue in the design and application of high-temperature heat pipes is the startup problem. High-temperature heat pipes usually use alkali metals as working media, and alkali metals are solid at room temperature. The process of heat pipe startup is the process in which the working medium inside the heat pipe melts and evaporates, forming a continuous steam flow inside the steam chamber. In this process, the various heat and mass transfer mechanisms inside the heat pipe are relatively complex and difficult to solve accurately. The current heat pipe startup calculation based on the thermal resistance network method is based on the "forward" method, and considering that the isothermal nature of the startup part of the heat pipe steam chamber is good, the steam chamber part is divided into only two parts: the startup section and the unstarted section. The heat pipe used in the heat pipe micro-pile is 4m long, which is much longer than the common heat pipe of about 1m. Even if it is fully started, there is still a non-negligible temperature difference in the axial direction. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a heat pipe startup calculation method, a calculation device and a readable medium to solve the problem that the existing heat pipe startup calculation method has low accuracy.

[0005] To solve the above technical problems, the present invention provides a heat pipe startup calculation method, comprising: establishing a heat pipe thermal resistance network model, wherein the steam chamber in the heat pipe thermal resistance network model is divided into a plurality of node control bodies; calculating the temperature of each node control body based on the thermal resistance network method; judging one by one whether the temperature of the node control body exceeds the heat pipe startup temperature, if so, setting the node control body to a startup state, if not, setting the node control body to an unstarted state, and modifying the thermal resistance between the node control bodies in the unstarted state to control the heat flow transfer process inside the heat pipe.

[0006] Optionally, calculating the temperature of each node control body based on the thermal resistance network method includes: establishing a differential equation of each node control body based on the thermal resistance network method, and solving the differential equation to obtain the temperature of each node control body.

[0007] Optionally, the differential equation of each node control volume is:

[0008]

[0009] Where: i —The density of the control volume of the i-th node;

[0010] V i —The volume of the volume controlled by the i-th node;

[0011] C i —Specific heat capacity of the i-th node control volume;

[0012] T i , T j — are the temperature of the i-th node control volume and the temperature of the j-th node control volume respectively;

[0013] R ij —Thermal resistance between the i-th node control body and the j-th node control body;

[0014] n is the total number of node control bodies adjacent to the i-th node control body.

[0015] Optionally, modifying the thermal resistance between the node control bodies in the unactivated state includes: modifying the thermal resistance R in the differential equation of the node control body ij The value of .

[0016] Optionally, the method further includes: solving the differential equation of the modified node control body for one time step to obtain the temperature of each node control body in the heat pipe in the next time step; judging whether the temperature of each node control body in the heat pipe in the next time step exceeds the start-up temperature of the heat pipe, and if so, setting the node control body to a start-up state; if not, setting the node control body to a non-start-up state, and modifying the thermal resistance between the node control bodies in the non-start-up state.

[0017] Optionally, modifying the thermal resistance between node control bodies in the unstarted state includes: calculating the thermal resistance between node control bodies in the started state, recorded as a first thermal resistance; and modifying the thermal resistance between node control bodies in the unstarted state to N times the first thermal resistance, where N>1.

[0018] Optionally, the first thermal resistance is calculated according to the flow pressure drop of the vapor in the heat pipe.

[0019] Optionally, the first thermal resistance is calculated by the following formula:

[0020]

[0021] Where: μ v —dynamic viscosity of the vapor in the node control volume;

[0022] R g —gas constant;

[0023] Tv —steam temperature of the node;

[0024] L—length corresponding to node thermal resistance;

[0025] ρ v —node vapor density;

[0026] r v —radius of the vapor chamber;

[0027] P v —saturation pressure of the vapor chamber;

[0028] h fg — Latent heat of vaporization of working fluid;

[0029] In order to solve the above technical problems, the present invention provides a heat pipe startup calculation device, comprising:

[0030] a memory for storing instructions executable by a processor;

[0031] A processor is used to execute the instructions to implement the calculation method as described above.

[0032] In order to solve the above technical problem, the present invention provides a computer readable medium storing a computer program code, wherein the computer program code implements the above-mentioned calculation method when executed by a processor.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] The heat pipe startup calculation method, calculation device and readable medium of the present invention divide the steam chamber of the heat pipe into multiple node control bodies, and make a heat pipe startup judgment by comparing the temperature of each node control body with the heat pipe startup temperature, and make a judgment on the entire heat pipe, so that the calculation result is more accurate; the present invention combines the thermal resistance network method to solve the heat pipe startup, and the judgment of the heat pipe startup and the modification process of the axial thermal resistance of the steam chamber do not change the structure of the heat pipe thermal resistance network model, that is, the form of the differential equation is not changed, and only the value of the thermal resistance in the differential equation is changed, thereby improving the versatility of the model. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present invention. In the accompanying drawings:

[0036] Figure 1 is a flow chart of a heat pipe startup calculation method according to an embodiment of the present invention;

[0037] Figure 2 is a heat pipe thermal resistance network model according to an embodiment of the present invention;

[0038] Figure 3 yes Figure 1 Flow chart of the heat pipe startup calculation method of the optimized embodiment;

[0039] Figure 4 is a flow chart of a heat pipe startup calculation method according to a specific embodiment;

[0040] Figure 5 4 is a system block diagram of a heat pipe activated computing device according to an embodiment of the present application. DETAILED DESCRIPTION

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0042] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0043] As mentioned in the background technology, the current heat pipe startup calculation based on the thermal resistance network method is based on the assumption that the startup part of the heat pipe vapor chamber is isothermal, and the vapor chamber is only divided into two parts: the startup section and the unstarted section. The heat pipe used in the heat pipe micro-pillar is 4 meters long, which is much longer than the common heat pipe of about 1 meter. Even if it is fully started, there is still a non-negligible temperature difference in the axial direction.

[0044] The heat pipe startup calculation method of the present application divides the steam chamber of the heat pipe into multiple node control bodies, and makes a heat pipe startup judgment by comparing the temperature of each node control body with the heat pipe startup temperature, thereby making a judgment on the entire heat pipe, and the result is more accurate.

[0045] Figure 1 FIG. 1 is a flow chart of a heat pipe startup calculation method according to an embodiment of the present invention. Figure 1 As shown, the heat pipe startup calculation method 100 includes the following steps:

[0046] Step S11: establishing a heat pipe thermal resistance network model, in which the vapor cavity is divided into a plurality of node control bodies.

[0047] The thermal resistance network model equates the thermal resistance of each part in the heat pipe to a resistor, and makes a thermal resistance network diagram based on the circuit diagram. Figure 2 is a heat pipe thermal resistance network model according to an embodiment of the present invention. Figure 2 As shown, in the heat pipe thermal resistance network model 200, the heat pipe can be divided into an evaporation section, an insulation section, and a condensation section axially according to the boundary. The evaporation section is connected to the reactor core, the condensation section is connected to the heat exchanger, and the middle is an insulation section. The heat pipe can be divided into a pipe wall, a liquid wick, and a steam cavity radially. The heat pipe is divided into a plurality of node control bodies by grid division, and the temperature of each node control body is represented by a temperature node (it can be understood that the heat pipe is divided into a plurality of sub-regions, and the temperature of each sub-region is represented by a temperature node). In other words, a temperature node represents a node control body. The node control bodies are connected by thermal resistance. Figure 2 The horizontal rectangle in the middle represents the axial thermal resistance, the vertical rectangle represents the radial thermal resistance, and the black dot represents the temperature node. In the label, E represents the evaporation section, A represents the adiabatic section, C represents the condensation section, S represents the tube wall, W represents the wick, and V represents the steam chamber. Then REV1 represents the thermal resistance between the node control bodies in the steam chamber of the evaporation section, RAV1 represents the thermal resistance between the node control bodies in the steam chamber of the adiabatic section, and RCV1 represents the thermal resistance between the node control bodies in the steam chamber of the condensation section. The meanings of other parameters (such as RES1 and RCW1, etc.) are inferred accordingly and will not be repeated here. The heat conduction of the tube wall and the wick is a two-dimensional conduction process, and the steam flow in the steam chamber is a one-dimensional flow process along the axial direction. The steam chamber is divided into a temperature node in the evaporation section, b temperature nodes in the adiabatic section, and c temperature nodes in the condensation section in the axial direction. In other words, the steam chamber is divided into a node control body in the evaporation section, b node control bodies in the adiabatic section, and c node control bodies in the condensation section in the axial direction. Among them, the number of a, b, and c is not fixed, and should be determined by comprehensively considering the calculation amount and simulation accuracy. exist Figure 2 In the figure, the steam chamber is divided into 4 temperature nodes in the axial direction, 2 temperature nodes in the adiabatic section, and 4 temperature nodes in the condensation section. The thermal resistance of the adiabatic section tube wall and the wick is relatively large, and the actual heat transfer is relatively small, so the heat transfer process is ignored. When the heat pipe is working, the heat conduction of the evaporation section tube wall, the heat conduction and convection of the evaporation section wick and its internal liquid working medium, the evaporation phase change, the axial flow heat transfer of steam, the condensation of steam, the heat conduction and convection of the wick in the condensation section, and the heat conduction of the condensation section tube wall are carried out in sequence.

[0048] Step S12: Calculate the temperature of each node control body based on the thermal resistance network method.

[0049] Optionally, calculating the temperature of each node control body based on the thermal resistance network method includes:

[0050] Step S121: According to the established heat pipe thermal resistance network model and energy conservation equation,

[0051] The node control volume establishes the differential equation:

[0052]

[0053] Where: i —The density of the control volume of the i-th node;

[0054] V i —The volume of the volume controlled by the i-th node;

[0055] C i —Specific heat capacity of the i-th node control volume;

[0056] T i , T j — are the temperature of the i-th node control volume and the temperature of the j-th node control volume respectively;

[0057] R ij —Thermal resistance between the i-th node control body and the j-th node control body;

[0058] n is the total number of node control bodies adjacent to the i-th node control body;

[0059] is the differentiation of the i-th node control volume for one time step.

[0060] The boundary conditions of the tube wall of the evaporation section of the heat pipe are provided by the core, and the boundary conditions of the tube wall of the condensation section are provided by the heat exchanger.

[0061] Step S122: Solve the differential equation to obtain the temperature of each node control body.

[0062] The differential equations can be solved using numerical algorithms to obtain the temperature of each node control body in the heat pipe. The numerical algorithms include but are not limited to the variable step size fourth-order Runge-Kutta method.

[0063] Step S13: Determine one by one whether the temperature of the node control body exceeds the heat pipe startup temperature. If yes, set the node control body to the startup state. If not, set the node control body to the unstarted state, and modify the thermal resistance between the node control bodies in the unstarted state to control the heat flow transfer process inside the heat pipe.

[0064] The startup characteristic of a high-temperature heat pipe is that the free molecular flow in the vapor chamber is transformed into a continuous vapor flow. The startup process of a heat pipe can be regarded as the process in which the internal continuous vapor flow advances from the evaporation section to the condensation section. According to research, the continuous vapor flow conversion in a heat pipe occurs at a specific temperature T s This temperature is related to the working medium type and size of the heat pipe and is called the heat pipe start-up temperature. Therefore, the heat pipe start-up judgment is performed, that is, the current temperature of the heat pipe vapor chamber is compared with the heat pipe start-up temperature.

[0065] This step requires starting judgment of all node control bodies in the vapor chamber of the heat pipe. Taking a node control body of a vapor chamber as an example, the heat pipe starting temperature is used as the judgment standard:

[0066] When T i ≥T s , the node control body is in the startup state, when T i <T s , the node control body is not started.

[0067] All node control bodies of the steam chamber are judged in turn to obtain the startup status of all node control bodies of the steam chamber, thereby obtaining the startup status of the entire heat pipe. According to the startup status of the heat pipe, the heat pipe can be divided into a started area and an unstarted area in the axial direction of the steam chamber. Whether the heat pipe is started or not affects the axial heat transfer of the steam chamber, which corresponds to the axial thermal resistance term in the differential equation of the node control body of the steam chamber in the thermal resistance network method. Optionally, modifying the thermal resistance between the node control bodies in the unstarted state includes modifying the thermal resistance R in the differential equation of the node control body. ij The value of .

[0068] The axial thermal resistance of the activated area can be calculated based on the flow pressure drop formula of the steam in the heat pipe:

[0069]

[0070] Where: μ v —dynamic viscosity of the vapor in the node control volume;

[0071] R g —gas constant;

[0072] T v —steam temperature of the node;

[0073] L—length corresponding to node thermal resistance;

[0074] ρ v —node vapor density;

[0075] r v —radius of the vapor chamber;

[0076] P v —saturation pressure of the vapor chamber;

[0077] h fg — Latent heat of vaporization of working fluid;

[0078] The axial thermal resistance of the unactivated area is modified to N times the axial thermal resistance of the activated area, where N>1. Preferably, the axial thermal resistance of the unactivated area is modified to twice the activated thermal resistance according to the empirical value, and the thermal resistance can also be corrected to other values ​​according to the heat pipe experimental results, so that the axial temperature of the steam chamber drops rapidly near the heat pipe startup interface. While modifying the axial thermal resistance of the steam chamber, it is only necessary to modify the thermal resistance value in the heat pipe differential equation so that the equation conforms to the state of the heat pipe under the current state. The modification process of the axial thermal resistance of the steam chamber in the present application does not change the structure of the heat pipe thermal resistance network model. That is, the form of the differential equation is not changed, only the value of the thermal resistance in the differential equation is changed, which improves the versatility of the model.

[0079] The heat pipe startup calculation method of the present application divides the steam chamber of the heat pipe into multiple node control bodies, and makes a heat pipe startup judgment by comparing the temperature of each node control body with the heat pipe startup temperature. The entire heat pipe is judged, and the calculation result is more accurate. The heat pipe startup calculation method of the present application can simulate the temperature distribution at each position when the heat pipe is started.

[0080] Figure 3 yes Figure 1 Flow chart of the heat pipe startup calculation method of the optimized embodiment. Figure 3 As shown, the heat pipe startup calculation method 300 also includes the following steps:

[0081] Step S14: Solve the differential equation of the modified node control body for one time step to obtain the temperature of each node control body in the heat pipe in the next time step.

[0082] Step S15: Determine whether the next time step reaches the preset end time, if yes, end; if not, go to step S13.

[0083] In order to facilitate understanding of the technical solution of the present application, a more specific embodiment is used below to illustrate the technical solution of the present application. Figure 4 The invention is a flow chart of a heat pipe startup calculation method according to a specific embodiment.

[0084] like Figure 4 As shown, the heat pipe startup calculation method 400 includes:

[0085] Step S41: heat pipe node division, the following nodes all represent temperature nodes.

[0086] Step S42: establishing differential equations for each node based on the thermal resistance network method.

[0087] Step S43: Determine whether the temperature of the i-th node is greater than the heat pipe start-up temperature. If so, set the i-th node control body to the start-up state, and then proceed to step S44; if not, proceed to step S45.

[0088] The temperature of each node at the initial time (time T=T0) can be set to the indoor temperature. The temperature of each node at subsequent times is obtained by solving differential equations.

[0089] Step S44: Determine whether i is less than imax. If yes, axially advance i=i+1 and proceed to step S43. If no, proceed to step S47. Wherein imax is the total number of node control bodies in the steam chamber, i.e., imax=a+b+c. The above can be understood as determining whether the temperature of the node control body is greater than the heat pipe startup temperature from the node control body of the evaporation section to the node control body of the condensation section in the steam chamber, and obtaining the startup status of all the node control bodies in the steam chamber, thereby obtaining the startup status of the entire heat pipe.

[0090] Step S45: If the temperature of the i-th node is less than or equal to the heat pipe start-up temperature, modify the axial thermal resistance of the node control body.

[0091] Step S46: Modify the differential equation according to the modified axial thermal resistance.

[0092] Step S47: Solve the modified differential equation for one time step to obtain the temperature of each node control body in the heat pipe in the next time step.

[0093] Step S48: Determine whether the next time step T+dt is less than Tmax. If so, advance the time by T=T+dt, and then go to step S43, where Tmax is the preset end time.

[0094] From the above process, it can be seen that the temperature distribution at each position in the heat pipe steam chamber is an iterative process over time, and it progresses with the time step until the end time is reached. As the time step progresses, the heat pipe receives the heat from the core, the temperature of the steam chamber gradually increases, and the node control body determined to be started gradually expands to the condensation section until the entire heat pipe is started. This simulates the process of the steam interface with a large temperature difference moving from the evaporation section to the condensation section during the startup process.

[0095] The present application also includes a heat pipe startup calculation device, including a memory and a processor, wherein the memory is used to store instructions executable by the processor; the processor is used to execute the instructions to implement a heat pipe startup calculation method mentioned above.

[0096] Figure 5 is a system block diagram of a heat pipe startup computing device according to an embodiment of the present application. Figure 5As shown, the heat pipe startup computing device 500 may include an internal communication bus 501, a processor 502, a read-only memory (ROM) 503, a random access memory (RAM) 504, and a communication port 505. When applied to a personal computer, the heat pipe startup computing device 500 may also include a hard disk 506. The internal communication bus 501 can realize data communication between the components of the heat pipe startup computing device 500. The processor 502 can make judgments and issue prompts. In some embodiments, the processor 502 can be composed of one or more processors. The communication port 505 can realize data communication between the heat pipe startup computing device 500 and the outside. In some embodiments, the heat pipe startup computing device 500 can send and receive information and data from the network through the communication port 505. The heat pipe startup computing device 500 may also include different forms of program storage units and data storage units, such as a hard disk 506, a read-only memory (ROM) 503 and a random access memory (RAM) 504, which can store various data files used for computer processing and / or communication, and possible program instructions executed by the processor 502. The processor executes these instructions to implement the main part of the method. The result processed by the processor is transmitted to the user device through the communication port and displayed on the user interface.

[0097] The above-mentioned operation method can be implemented as a computer program, stored in the hard disk 506, and loaded into the processor 502 for execution to implement the heat pipe startup calculation method of the present application.

[0098] The present application also includes a computer readable medium storing a computer program code, which implements the above heat pipe startup calculation method when executed by a processor.

[0099] When the heat pipe startup calculation method is implemented as a computer program, it can also be stored in a computer-readable storage medium as a product. For example, a computer-readable storage medium may include, but is not limited to, a magnetic storage device (e.g., a hard disk, a floppy disk, a magnetic strip), an optical disk (e.g., a compact disk (CD), a digital versatile disk (DVD)), a smart card, and a flash memory device (e.g., an electrically erasable programmable read-only memory (EPROM), a card, a stick, a key drive). In addition, the various storage media described herein can represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media (and / or storage media) that can store, contain and / or carry code and / or instructions and / or data.

[0100] The basic concepts have been described above. Obviously, for those skilled in the art, the above invention disclosure is only used as an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0101] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0102] Some aspects of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". The processor may be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. In addition, various aspects of the present application may be expressed as computer products located in one or more computer-readable media, which include computer-readable program codes. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, tapes ...), optical disks (e.g., compact disks CDs, digital versatile disks DVDs ...), smart cards, and flash memory devices (e.g., cards, sticks, key drives ...).

[0103] A computer-readable medium may include a propagated data signal containing computer program code, such as in baseband or as part of a carrier wave. The propagated signal may have a variety of manifestations, including electromagnetic, optical, etc., or a suitable combination. A computer-readable medium may be any computer-readable medium other than a computer-readable storage medium, which may be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit a program for use. The program code on the computer-readable medium may be propagated via any suitable medium, including radio, cable, fiber optic cable, radio frequency signal, or similar medium, or any combination of the above mediums.

[0104] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0105] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0106] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0107] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0108] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0109] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A heat pipe startup calculation method, characterized in that: include: Establishing a heat pipe thermal resistance network model, wherein the steam chamber in the heat pipe thermal resistance network model is divided into a plurality of node control bodies, and adjacent node control bodies are connected by thermal resistance; Calculate the temperature of each node control body based on the thermal resistance network method; Determine one by one whether the temperature of the node control body exceeds the heat pipe startup temperature. If yes, set the node control body to the startup state. If not, set the node control body to the unstarted state, and modify the thermal resistance between the node control bodies in the unstarted state to control the heat flow transfer process inside the heat pipe.

2. The calculation method according to claim 1, characterized in that: The temperature of each node control body is calculated based on the thermal resistance network method, including: Based on the thermal resistance network method, a differential equation of each node control body is established, and the temperature of each node control body is obtained by solving the differential equation.

3. The calculation method according to claim 2, characterized in that: The differential equations of each node control volume are: Where: i —The density of the control volume of the i-th node; V i —The volume of the volume controlled by the i-th node; C i —Specific heat capacity of the i-th node control volume; T i , T j — are the temperature of the i-th node control volume and the temperature of the j-th node control volume respectively; R ij —Thermal resistance between the i-th node control body and the j-th node control body; n is the total number of node control bodies adjacent to the i-th node control body.

4. The calculation method according to claim 3, characterized in that: Modifying the thermal resistance between the node control bodies in the unactivated state includes: modifying the thermal resistance R in the differential equation of the node control body ij The value of .

5. The calculation method according to claim 4, characterized in that: Also includes: Solve the differential equation of the modified node control body for one time step to obtain the temperature of each node control body in the heat pipe in the next time step; Determine whether the temperature of each node control body in the heat pipe exceeds the heat pipe startup temperature in the next time step. If yes, set the node control body to the startup state. If not, set the node control body to the unstarted state and modify the thermal resistance between the node control bodies in the unstarted state.

6. The calculation method according to claim 1, characterized in that: Modifying the thermal resistance between nodes in the unstarted state includes: Calculate the thermal resistance between the node control bodies in the startup state, recorded as the first thermal resistance; The thermal resistance between the node control bodies in the unstarted state is modified to N times the first thermal resistance, wherein N>1.

7. The calculation method according to claim 6, characterized in that: The first thermal resistance is calculated according to the flow pressure drop of the vapor in the heat pipe.

8. The calculation method according to claim 7, characterized in that: The first thermal resistance is calculated by the following formula: Where: μ v —dynamic viscosity of the vapor in the node control volume; R g —gas constant; T v —steam temperature of the node; L—length corresponding to node thermal resistance; ρ v —node vapor density; r v —radius of the vapor chamber; P v —saturation pressure of the vapor chamber; h fg —Latent heat of vaporization of working fluid.

9. A heat pipe activation calculation device, characterized in that: include: a memory for storing instructions executable by a processor; A processor, configured to execute the instructions to implement the calculation method according to any one of claims 1 to 8.

10. A computer-readable medium storing computer program codes, wherein the computer program codes, when executed by a processor, implement the computing method according to any one of claims 1 to 8.

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