Method and system for measuring the average temperature of a gas in a large volume closed structure

Abstract

The application discloses a method for measuring the average temperature of gas in a large-volume closed structure, which comprises the following steps: 3D model establishment of the internal space of the structure and spatial coordinate information of temperature sensors; mesh division on the 3D model; calculation of the gas energy exchange path of each mesh unit to each temperature sensor; calculation of the volume coefficient; and calculation of the average temperature of the internal gas in the structure. The application realizes the automatic calculation of the average temperature of the internal gas in the structure by using the 3D model of the structure and computer software, and can make the calculation of the average temperature of the internal gas in the large-volume structure more reasonable, the precision of which does not depend on the professional level of the technical personnel. When a certain temperature sensor fails, the volume coefficient can be automatically recalculated, and the accurate calculation of the average temperature of the internal gas volume in the structure is realized. In addition, the application discloses a system for measuring the average temperature of gas in a large-volume closed structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of measuring the average temperature of gas in a large-volume closed structure, and in particular to a method and system for measuring the average temperature of gas in a large-volume closed structure. BACKGROUND

[0002] In the calculation of the average temperature of gas in a nuclear power plant containment, the existing technology calculates the average temperature as follows: the free volume of each room is derived from the 3D model file of the structure; the deduction volume of each room, including the volume of concrete structure, steel structure, equipment, process piping and its accessories, support hanger structure, and cable and its bridge, is derived from the 3D model file of the structure; the net free volume of the room is obtained by subtracting the deduction volume from the free volume; according to experience, the volume of each room is manually assigned to the corresponding temperature sensor, i.e., the volume coefficient of each temperature sensor is obtained; and the average temperature is calculated using the formula.

[0003] However, the existing scheme is a manual calculation scheme, which has obvious defects, as follows:

[0004] 1) Generally, the smallest unit in the volume range represented by the temperature sensor is a room, and if the room is small, the volume of the room can be added to the probe. However, if the room volume is large, according to the actual situation, the room volume may need to be assigned to two probes, but it is difficult to manually adjust the assignment scheme, and if it is not adjusted, there may be obvious unreasonable situations;

[0005] 2) In the containment, the gas temperature is not uniform, and the gas parameters on both sides of the wall are quite different after the space is isolated by the wall. If the "ownership" of the room free volume is simply determined according to the straight-line distance of the space, the measured temperature of the temperature sensor may not well represent the temperature of the room, resulting in inaccurate results;

[0006] 3) If a temperature sensor fails, the volume coefficient of the temperature sensor needs to be assigned to other probes. In the existing technical scheme, after the temperature sensor fails, the volume coefficient of the temperature sensor is simply and evenly assigned to the two adjacent temperature sensors, which has obvious unreasonable situations;

[0007] 4) Manual calculation is low in efficiency, and the calculation amount is large and time-consuming after the sensor fails;

[0008] 5) Manual calculation requires a high level of technical expertise;

[0009] Therefore, it is necessary to provide a method and system for accurately measuring the average temperature of gas in a large-volume closed structure. SUMMARY

[0010] The purpose of this invention is to overcome at least one deficiency of the prior art and provide a method and system for accurately measuring the average temperature of gases in large-volume enclosed structures.

[0011] To achieve the above-mentioned objective, the present invention provides a method for measuring the average temperature of gases in a large-volume enclosed structure, comprising the following steps:

[0012] The creation of a 3D model of the interior space of the structure, and the spatial coordinate information of the temperature sensor;

[0013] The above 3D model is meshed;

[0014] Calculation of the gas energy exchange path from each grid cell to each temperature sensor;

[0015] Calculation of volume factor;

[0016] Calculation of the average temperature of the gas inside the structure.

[0017] According to one embodiment of the method for measuring the average gas temperature of a large-volume enclosed structure according to the present invention, a three-dimensional model of the structure is established using three-dimensional software such as SolidWorks, UG, and PDMS. The three-dimensional model should include all gas boundaries within the structure. The three-dimensional model is imported into finite element software such as ANSYS and HYPERMESH, and the model is divided into first-order tetrahedral elements, with each tetrahedral element generally not larger than 40 cm. The tetrahedral elements are then stored in a txt file.

[0018] According to one embodiment of the method for measuring the average gas temperature of a large-volume enclosed structure according to the present invention, the above-mentioned 3D model is meshed, and the steps are as follows:

[0019] After establishing the structure model, the smallest cuboid that can contain the structure can be obtained. Each side of the cuboid is parallel to the xyz coordinate axis, and the length, width and height are rounded to L / W / H.

[0020] The cuboid is divided into cubic micro-units V with a side length of 1 cm and a volume of 1 cm³. cubi The number of micro-units generated is n = LWH;

[0021] Calculate the coordinates of the center point of each cubic micro-unit, namely P. cubcenti ;

[0022] Create a three-dimensional array A to record the properties of cubic micro-units. property, three dimensions of size LWH, the cube micro-unit attributes are: obstacles, i.e. places where air convection cannot occur, not in the path of gas energy exchange, represented by 0; gas, places where air convection can occur, represented by 1; temperature sensor, represented by 2;

[0023] For each cube micro-unit V cubi , if the center point coordinate P cubcenti of the cube is outside the building boundary, then the A property of the unit is 0;

[0024] For the building boundary inside, if the center point coordinate P cubcenti of the cube is inside a certain tetrahedral unit P teti , then the center point of the cube micro-unit is on the building internal entity, and A property = 0 is taken; otherwise, the center point of the cube micro-unit is in the gas space inside the building, and A property = 1 is taken;

[0025] For the temperature sensor, the A property of the cube micro-unit where the coordinate is located is 2.

[0026] According to one embodiment of the method for measuring the average temperature of the gas in a large-volume closed building according to the present application, after the calculation of the gas energy exchange path of each grid unit to each temperature sensor and the obtaining of the cube micro-unit attribute array, the calculation of the subordinate temperature sensor of each cube micro-unit begins, i.e. the calculation of the corresponding temperature sensor to which the micro-unit should be divided; if the micro-unit belongs to sensor Tj, then the temperature of the unit is replaced by Tj.

[0027] According to one embodiment of the method for measuring the average temperature of the gas in a large-volume closed building according to the present application, the calculation method of the subordinate temperature sensor of each cube micro-unit is as follows:

[0028] The shortest path of the cube micro-unit to each temperature sensor Tj is calculated using the ant algorithm or the A* algorithm, respectively Lj.

[0029] The temperature sensor corresponding to the smallest Lj is the subordinate sensor of the cube micro-unit.

[0030] According to one embodiment of the method for measuring the average temperature of the gas in a large-volume closed building according to the present application, the calculation of the volume coefficient: the number of all cube micro-units with A property = 1 consistent with the subordinate sensor, i.e. the free volume volume V i represented by the temperature sensor, can be calculated to obtain the volume coefficient

[0031] According to one embodiment of the method for measuring the average temperature of the gas in a large-volume closed structure according to the present application, the calculation of the average temperature of the gas inside the structure is performed according to the following steps:

[0032] When the average temperature of the gas is calculated using the measurement results of multiple temperature sensors, it can be known from the ideal gas state equation that:

[0033] P i V i = n i RT i

[0034] wherein Vi is the volume of the surrounding free space represented by the i th temperature sensor, Ti is the temperature of the i th temperature sensor, n i represents the molar amount of the gas in the Vi volume, and R is the gas constant; since the pressure at each point in the structure is equal, the following can be obtained:

[0035]

[0036] In the formula: is the average temperature of the gas in the structure, and V is the volume of the gas in the structure; the average temperature calculation formula can be calculated as follows:

[0037]

[0038] It can be found from the above formula that the accuracy of the gas volume Vi directly affects the accuracy of the calculation result.

[0039] In order to achieve the above-mentioned purposes, the present application further provides a system for measuring the average temperature of the gas in a large-volume closed structure, comprising a measurement system, wherein the measurement system comprises a data processing computer, a data acquisition system, temperature sensors, temperature measuring cables, and a containment vessel;

[0040] The data processing computer is used to establish a 3D model of the structure, import the three-dimensional model into finite element software such as ANSYS and HYPERMESH, divide the model into first-order tetrahedral elements, store the model into a txt file, and has a calculation capability;

[0041] The data acquisition system connects the acquisition system, the temperature sensors, and the temperature measuring cables through data lines, and automatically acquires data in the temperature sensors and the temperature measuring cables.

[0042] According to one embodiment of the system for measuring the average temperature of the gas in a large-volume closed structure according to the present application, the temperature sensors are used to acquire the temperature inside the containment vessel;

[0043] The temperature measuring cables are used to measure the temperature inside the containment vessel;

[0044] The containment is used to block the fission products and primary loop radioactive substances from the fuel from entering the environment.

[0045] According to one embodiment of the system for measuring the average temperature of gas in a large-volume closed structure according to the application, each room in the containment is provided with a temperature sensor; each temperature sensor is uniformly arranged; the data acquisition system uses a multimeter with an accuracy of no less than 6 bits and a half; the temperature sensor has an accuracy of no less than AA level; the data acquisition system and the data processing computer are placed outside the containment, facilitating maintenance and analysis; and the temperature sensor and the temperature measuring cable are placed inside the containment.

[0046] Compared with the prior art, the method and system for measuring the average temperature of gas in a large-volume closed structure according to the application have the following advantages:

[0047] 1. The application uses a 3D model of the structure and computer software to automatically calculate the average temperature of gas in the structure, solving the problem that the prior art can only manually calculate; the application can make the average temperature of gas in a large-volume structure more reasonable, and the accuracy is not dependent on the professional level of the technician, solving the problem of high requirements for technicians and low efficiency of manual calculation; when a temperature sensor fails, the volume coefficient can be automatically recalculated, and the accurate calculation of the average temperature of gas in the structure is realized, solving the problems of low calculation accuracy and long calculation time in the manual calculation scheme.

[0048] 2. The application can realize high-precision measurement of the average temperature of gas in a large-volume closed structure; the application can make the average temperature of gas in a large-volume structure more reasonable, and the accuracy is not dependent on the professional level of the technician, solving the problem of high requirements for technicians and low efficiency of manual calculation; the safety quality is improved, and human error is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0049] The method and system for measuring the average temperature of gas in a large-volume closed structure according to the application will be described in detail below with reference to the accompanying drawings and specific embodiments, in which:

[0050] Figure 1 A flowchart of a method for measuring the average temperature of gas in a large-volume closed structure according to the application is shown in the figure.

[0051] Figure 2 A volume coefficient calculation flowchart of a method for measuring the average temperature of gas in a large-volume closed structure according to the application is shown in the figure.

[0052] Figure 3 A schematic diagram of a system for measuring the average temperature of gas in a large-volume closed structure according to the application is shown in the figure. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application.

[0054] With reference to Figures 1-2 According to the present application, a method for measuring the average temperature of gas in a large-volume closed structure is provided, which comprises the following steps:

[0055] 3D modeling of the internal space of the structure, and spatial coordinate information of the temperature sensors;

[0056] Grid division of the 3D model;

[0057] Calculation of the gas energy exchange path of each grid unit to each temperature sensor;

[0058] Calculation of the volume coefficient;

[0059] Calculation of the average temperature of the gas in the internal space of the structure.

[0060] The 3D model of the structure is established by using 3D software such as solidworks, UG, PDMS, etc. The 3D model should include all the boundaries of the gas in the structure. The 3D model is imported into finite element software such as ANSYS and HYPERMESH. The model is divided into first-order tetrahedral units, and the tetrahedral units are generally not greater than 40 cm. The above-mentioned tetrahedral units are stored in a txt file.

[0061] The 3D model is divided into grids, and the steps are as follows:

[0062] After the aforementioned establishment of the model of the structure, the smallest cuboid containing the structure can be obtained. The edges of the cuboid are parallel to the xyz coordinate axes, and the length, width and height are rounded to L / W / H.

[0063] The cuboid is divided into cubic micro-units V cubi , and the number of generated micro-units is n=LWH.

[0064] The center point coordinates of each cubic micro-unit are calculated, which are P cubcenti , respectively.

[0065] A three-dimensional array A property is created to record the properties of the cubic micro-units. The sizes of the three dimensions are LWH, respectively. The properties of the cubic micro-units include: obstacles, i.e. places where air convection cannot occur, which are not in the path of gas energy exchange, represented by 0; gas, i.e. places where air convection can occur, represented by 1; temperature sensors, represented by 2.

[0066] For each cubic micro-cell V cubi , if the center point coordinate P cubcenti of the cubic is outside the building boundary, then the A property of the cell is 0;

[0067] For the cubic inside the building boundary, if the center point coordinate P cubcenti of the cubic is inside a certain tetrahedral cell P teti , then the center point of the cubic micro-cell is on the solid inside the building, and A property = 0; otherwise, the center point of the cubic micro-cell is in the gas space inside the building, and A property = 1;

[0068] For the temperature sensor, the A property of the cubic micro-cell where the coordinate of the sensor is located is 2.

[0069] After the calculation of the gas energy exchange path of each grid cell to each temperature sensor, the calculation of the dependent temperature sensor of each cubic micro-cell begins, that is, the micro-cell needs to be divided to the corresponding temperature sensor; if the micro-cell belongs to sensor Tj, then the temperature of the cell is replaced by Tj.

[0070] The calculation method of the dependent temperature sensor of each cubic micro-cell is as follows:

[0071] The shortest path of the cubic micro-cell to each temperature sensor Tj is calculated using the ant algorithm or A* algorithm, which is Lj, respectively.

[0072] The temperature sensor corresponding to the smallest Lj is the dependent sensor of the cubic micro-cell.

[0073] The calculation of the volume coefficient: the number of all cubic micro-cells with A property = 1 consistent with the dependent sensor is the free volume volume V i represented by the temperature sensor, and the volume coefficient

[0074] The calculation steps of the calculation of the average temperature of the gas inside the building are as follows:

[0075] When the average temperature of the gas inside the building is calculated using the measurement results of multiple temperature sensors, it can be known from the ideal gas state equation that:

[0076] P i V i = n i RT i

[0077] Wherein: Vi is the ambient free space gas volume represented by the i th temperature sensor, Ti is the temperature of the i th temperature sensor, n i Indicates the gas molar quantity in the Vi volume, R is the gas constant; since the pressure at each point in the structure is equal, the following can be obtained:

[0078]

[0079] In the formula: The average temperature of the gas in the structure, V is the volume of the gas in the structure; the average temperature calculation formula can be calculated as follows:

[0080]

[0081] From the above formula, it can be found that the accuracy of the gas volume Vi directly affects the accuracy of the calculation result.

[0082] Referring to Figure 3 The present application provides a kind of system for measuring the average temperature of gas in large volume closed structure, including measurement system, measurement system includes data processing computer, data acquisition system, temperature sensor, temperature measuring cable and containment;

[0083] Data processing computer is used to establish the 3D model of structure, three-dimensional model is imported into ANSYS, HYPERMESH etc. Finite element software, and the model is divided into first-order tetrahedron unit and stored to txt file, and it has computing ability;

[0084] Data acquisition system is connected by data line with temperature sensor and temperature measuring cable, and the data in temperature sensor and temperature measuring cable are automatically collected.

[0085] Wherein, temperature sensor is used to collect the temperature inside containment;

[0086] Temperature measuring cable is used to measure the temperature inside containment;

[0087] Containment is used to block the fission products from fuel and the radioactive substances in primary loop from entering the environment.

[0088] Wherein, each room in containment is provided with temperature sensor;Each temperature sensor is uniformly arranged;The precision of multimeter used by data acquisition system is not less than 6 bit half;The precision of temperature sensor is not less than AA level;Data acquisition system and data processing computer are placed outside containment, which is convenient for maintenance and analysis;Temperature sensor and temperature measuring cable are placed inside containment.

[0089] In combination with the detailed description of the embodiments of the present application, it can be seen that, compared with the prior art, the method and system for measuring the average temperature of gas in large volume closed structure have the following advantages:

[0090] 1、The present application uses the 3D model of the structure and computer software to realize the automatic calculation of the average temperature of the gas in the structure, solves the problem that only manual calculation can be realized in the prior art, and makes the average temperature calculation of the gas in the large-volume structure more reasonable, the precision of which does not depend on the professional level of the technical personnel, solves the problem of high requirement for the technical personnel and low efficiency of manual calculation, and when a certain temperature sensor fails, the volume coefficient can be automatically recalculated, and the accurate calculation of the average temperature of the gas in the structure is realized, solving the problems of low calculation precision and long calculation time in the manual calculation scheme.

[0091] 2、The present application can realize the high-precision measurement of the average temperature of the gas in the large-volume closed structure, makes the average temperature calculation of the gas in the large-volume structure more reasonable, the precision of which does not depend on the professional level of the technical personnel, solves the problem of high requirement for the technical personnel and low efficiency of manual calculation, improves the safety quality, and reduces the human error.

[0092] According to the above principles, the above embodiments can also be appropriately changed and modified. Therefore, the present application is not limited to the specific embodiments disclosed and described above, and some modifications and changes of the present application should fall within the protection scope of the claims of the present application. In addition, although some specific terms are used in the specification, these terms are only for convenience of description and do not constitute any limitation on the present application.

Claims

1. A method of measuring the average temperature of a gas in a large volume enclosed structure, characterised in that, It comprises the following steps: 3D model of the internal space of the structure is established, and the spatial coordinate information of the temperature sensor is obtained; The 3D model is meshed, and the steps are as follows: After the 3D model of the internal space of the structure is established, the smallest cuboid containing the structure can be obtained, and the length, width and height of the cuboid are rounded to L / W / H; The cuboid is divided into cubic micro-units with a side length of 1 cm and a volume of 1 cm³ V cubi The number of micro-units generated is n = LWH; The center point coordinates of each cubic microcell are calculated, respectively P cubcenti ; creating a three-dimensional array of cubelets properties A property , with three dimensions of size LWH, the cubelets properties are: obstacle, i.e. places where air convection cannot occur, not in the path of the gas energy exchange, represented by 0; gas, i.e. places where air convection can occur, represented by 1; temperature sensor, represented by 2; For each cubic microcell V cubi if the center point coordinate P cubcenti of the cubic is outside the structure boundary, then the value of the cell A property =0; For the inside of the building boundary, if the center point coordinate of the cube P cubcenti In a certain tetrahedral unit P teti , then the cube micro-unit center point is on the building interior entity, take A property = 0; otherwise, say the cube micro-unit center point is in the gas space inside the building, take A property = 1; For the temperature sensor, the coordinates of the cubic microcell in which it is located A property = 2; The calculation of the gas energy exchange path of each grid unit to each temperature sensor; The calculation of the volume coefficient; The calculation of the average temperature of the gas in the structure.

2. The method of measuring the average temperature of the gas in a large volume enclosed structure of claim 1 wherein, A three-dimensional model of the structure is established using three-dimensional software such as solidworks, UG and PDMS; the three-dimensional model includes all the boundaries of the gas in the structure, and the three-dimensional model is imported into finite element software ANSYS and HYPERMESH, and the model is divided into first-order tetrahedral units, and the tetrahedral units are not greater than 40 cm; the above-mentioned tetrahedral units are stored in a txt file.

3. The method of measuring the average temperature of the gas in a large volume enclosed structure of claim 1 wherein, After obtaining the cubic micro-unit attribute array, the calculation of the subordinate temperature sensor of each cubic micro-unit is started, that is, it is necessary to calculate the micro-unit which needs to be divided into the corresponding temperature sensor; if the micro-unit belongs to sensor Tj, the temperature of the unit is replaced by Tj.

4. The method of measuring the average temperature of the gas in a large volume enclosed structure of claim 3, wherein, The calculation method of the subordinate temperature sensor of each cubic micro-unit is as follows: The shortest path of the cubic micro-unit to each temperature sensor Tj is calculated using ant algorithm or A* algorithm, respectively, which is Lj. The temperature sensor corresponding to the smallest Lj is the subordinate sensor of the cubic micro-unit.

5. The method of measuring the average temperature of the gas in a large volume enclosed structure of claim 1 wherein, Calculation of the volume coefficient: all the slave sensors are consistent A property =1 the number of cubic micro-units, V i the free volume volume represented by the i-th temperature sensor, V The volume coefficient can be calculated by the volume of the gas in the structure .

6. The method of measuring the average temperature of the gas in a large volume enclosed structure of claim 1 wherein, The calculation steps of the average temperature of the gas in the structure are as follows: When calculating the average temperature using multiple temperature sensor measurement results, it can be known from the ideal gas state equation that: wherein: V i Vf is the free volume of the volume represented by the i-th temperature sensor, T i T is the temperature of the i-th temperature sensor, represents V i the molar amount of gas within the volume, R being the gas constant; since the pressure is equal at each point within the structure, it follows that: where: is the average temperature of the gas within the structure, V is the volume of the gas within the structure; the average temperature can be calculated using the following formula: 。 7. A system for measuring the average temperature of the gas in a large volume closed structure by the method according to any one of claims 1 to 6, characterized in that, The measurement system comprises a data processing computer, a data acquisition system, a temperature sensor, a temperature measuring cable and a containment vessel; The data processing computer is used to establish a 3D model of the structure, import the three-dimensional model into finite element software ANSYS and HYPERMESH, divide the model into first-order tetrahedral units and store it in a txt file, and has calculation capability; The data acquisition system connects the acquisition system, the temperature sensor and the temperature measuring cable through data lines, and automatically acquires data in the temperature sensor and the temperature measuring cable.

8. The system for measuring the average temperature of the gas in a large volume enclosed construction according to claim 7, characterized in that, The temperature sensor is used to acquire the temperature inside the containment vessel; The temperature measuring cable is used to measure the temperature inside the containment vessel; The containment vessel is used to block the fission products and the primary loop radioactive substances from the fuel from entering the environment.

9. The system for measuring the average temperature of the gas in a large volume enclosed structure of claim 7, wherein, Each room in the containment vessel is provided with the temperature sensor; each temperature sensor is uniformly arranged; the precision of the multimeter used by the data acquisition system is not less than 6 bits and a half; the precision of the temperature sensor is not less than AA level; the data acquisition system and the data processing computer are placed outside the containment vessel, which is convenient for maintenance and analysis; the temperature sensor and the temperature measuring cable are placed inside the containment vessel.

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