A method for judging the temperature and component concentration uniformity in a high-temperature gas pool

Abstract

A method for judging the uniformity of temperature and component concentration in a high-temperature gas pool, which includes the steps of establishing a flow channel simulation model, simulating and accepting the simulation model, obtaining the simulated absorbance, obtaining the experimental absorbance, and finally judging the uniformity. Specifically, first obtain a flow channel simulation model that meets the acceptance criteria for temperature and component concentration uniformity, and obtain the simulated temperature and component concentration data, that is, the simulated absorbance. Then, based on the flow channel simulation model, manufacture an actual flow channel. Then, under the same conditions as the previous simulation in the actual flow channel, conduct experiments to obtain the experimental temperature and component concentration data, that is, the experimental absorbance. Finally, compare the simulated absorbance and the experimental absorbance to finally judge the uniformity of temperature and component concentration. This design not only has a relatively simple judgment process and low cost, but also is easy to operate and has high accuracy.

Description

Technical Field

[0001] The invention relates to a design of a high-temperature gas pool, belonging to the technical field of spectrum detection and equipment manufacturing, and in particular to a method for judging the uniformity of temperature and component concentration in a high-temperature gas pool. Background Art

[0002] High-temperature gas cells are widely used in gas sensor design and molecular spectral parameter measurement, and have become an indispensable carrier in the basic research and large-scale application of gas sensing. With the transformation and upgrading of traditional industries to high-end, high-temperature thermal processes have put forward new requirements for the accuracy and fidelity of gas measurement. At the same time, one-way gas cells, Herriott gas cells, and White-type gas cells have gradually shifted from conventional room temperature environments to high-temperature scenarios. The accurate measurement of high-temperature gases is inseparable from stable and reliable high-temperature gas cells. Uniform temperature and gas distribution environment (i.e. uniform gas component concentration) can ensure the reliability of molecular spectral parameter measurement and ensure the stability of high-temperature gas absorption spectrum signals.

[0003] At present, after the high-temperature gas pool is designed, thermocouples are usually buried at different positions in the gas pool, and the uniformity of the gas temperature in the gas pool is determined by monitoring the consistency of the thermocouple readings. In order to ensure the uniformity of the concentration of the target gas in the gas pool, it is often achieved through a cycle of multiple extraction and replenishment of the target gas.

[0004] It should be noted that the above method can ensure the uniformity of temperature and component concentration distribution to a certain extent, but its implementation is too dependent on experience. At the same time, it often requires a long waiting time to achieve uniformity of concentration.

[0005] Therefore, for a high-temperature gas pool that is still in the preliminary design or optimization stage, a large amount of manpower and material resources are needed to carry out a large number of experimental tests and optimizations. At the same time, it is difficult to judge the uniformity within the high-temperature gas pool when conducting gas measurement experiments.

[0006] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of this patent application, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to ordinary technicians in this field. Summary of the invention

[0007] The purpose of the present invention is to overcome the defects and problems of the prior art in that the judgment process is relatively complicated and the cost is relatively high, and to provide a method for judging the uniformity of temperature and component concentration in a high-temperature gas pool with a relatively simple judgment process and low cost.

[0008] To achieve the above objectives, the technical solution of the present invention is: a method for determining the uniformity of temperature and component concentration in a high-temperature gas pool, comprising the following steps:

[0009] Step 1, the step of establishing a flow channel simulation model: Establish a two-dimensional model of the flow channel in the high-temperature gas pool in a finite element analysis software to obtain a flow channel simulation model. The flow channel simulation model includes an upper intake pipe, a lower intake pipe, a central gas chamber, an upper outlet pipe, and a lower outlet pipe, all of which are hollow structures. The middle part along the axial direction inside the central gas chamber is the central axis. The left end of the central gas chamber is respectively connected to the outlet ports of the upper intake pipe and the lower intake pipe, and the right end of the central gas chamber is respectively connected to the intake ports of the upper outlet pipe and the lower outlet pipe. The upper intake pipe, the left end of the central gas chamber, and the lower intake pipe together enclose a left rod cavity for inserting and mating with an optical rod. The upper outlet pipe, the right end of the central gas chamber, and the lower outlet pipe together enclose a right rod cavity for inserting and mating with an optical rod. Moreover, the top surface and the bottom surface of the central gas chamber are both heating surfaces;

[0010] Step 2, the step of simulating and accepting the simulation model: First, perform heating simulation and gas transportation simulation on the flow channel simulation model respectively, and then perform temperature acceptance judgment and concentration acceptance judgment based on the simulation results respectively. If both acceptance judgments pass, the simulation model is qualified;

[0011] The temperature acceptance judgment refers to: Check the temperature distribution map of the central gas chamber in the result of the heating simulation, and check the temperature distribution of each point on the central axis. If the temperature distribution map shows a uniform distribution and the temperature difference between each point on the central axis ≤ 2K, the judgment passes;

[0012] The concentration acceptance judgment refers to: Check the gas concentration distribution map of the central gas chamber in the result of the gas transportation simulation, and check the gas concentration of each point on the central axis. If the gas concentration distribution map shows a uniform distribution and the mass fraction difference between each point on the central axis ≤ 2%, the judgment passes;

[0013] Step 3, the step of obtaining the simulated absorbance: First, determine the optical path and the target gas, then respectively determine the simulated temperature and the simulated concentration based on the temperature and concentration of each point on the central axis in the above simulation results, and then perform calculations based on the simulated temperature and the simulated concentration to correspondingly obtain the simulated absorbance of temperature and the simulated absorbance of concentration; The simulated temperature is the maximum value, the minimum value, or the average value of the temperatures of each point on the central axis, and the simulated concentration is the maximum value, the minimum value, or the average value of the concentrations of each point on the central axis;

[0014] Step 4, the step of obtaining the experimental absorbance: First, establish an actual gas pool. The structure of the flow channel in the actual gas pool is the same as that of the above simulation model. Then, use the same optical path, target gas, temperature, or concentration as those in the above process of obtaining the simulated absorbance for the actual gas pool. Then, introduce a scanning laser that will be absorbed by the target gas through an optical rod, and then detect the absorption signal and perform limit fitting through a photodetector to correspondingly obtain the experimental absorbance of temperature and the experimental absorbance of concentration;

[0015] Step 5, the judgment step of final uniformity: Compare the simulated absorbance of temperature with the experimental absorbance of temperature. At the same time, compare the simulated absorbance of concentration with the experimental absorbance of concentration. If the simulated absorbance of temperature is basically the same as the experimental absorbance of temperature, and the simulated absorbance of concentration is basically the same as the experimental absorbance of concentration, it is determined that the temperature and the concentration of gas components in the actual gas cell are both uniform.

[0016] The fact that the simulated absorbance of temperature is basically the same as the experimental absorbance of temperature means that after comparison, the result is a curve, and the temperature difference at each point on this curve ≤ 2K, then it is basically the same;

[0017] The fact that the simulated absorbance of concentration is basically the same as the experimental absorbance of concentration means that after comparison, the result is a curve, and the mass fraction difference at each point on this curve ≤ 2%, then it is basically the same.

[0018] The so-called "after comparison of the two" means that based on the selected absorbance peak spectral signals of the simulated absorbance of temperature, the experimental absorbance of temperature, the simulated absorbance of concentration, and the experimental absorbance of concentration, substitute them into any of the following functions for solution:

[0019] The first kind:

[0020]

[0021] where n is the number of selected wave peaks, kf is the kth wave peak, αkf is the corresponding absorbance peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value;

[0022] The second kind:

[0023]

[0024] where n is the number of selected wave peaks, kf is the kth wave peak, αkf is the corresponding absorbance peak value, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value;

[0025] The third kind:

[0026]

[0027] where n is the number of selected wave peaks, kf is the kth wave peak, Akf is the corresponding integrated absorbance peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value;

[0028] The fourth kind:

[0029]

[0030] Among them, n is the number of selected wave peaks, kf is the k-th wave peak value, αkf is the corresponding absorbance wave peak value, Akf is the corresponding integrated absorbance wave peak value, ν0 is the central wave number of the laser, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value.

[0031] In the first step, establishing a two-dimensional model of the flow channel in the high-temperature gas cell in the finite element analysis software to obtain the flow channel simulation model means: first establishing a Solidworks model of the high-temperature gas cell, then importing it into the finite element analysis software, namely the DesignModeler module in Ansys software, then observing the shape of the flow channel in the high-temperature gas cell, then selecting the inlet and outlet, then extracting the flow channel from the high-temperature gas cell, then calling the Designmodeler function under the Fluid Flow function in Ansys to establish a sketch, then drawing a two-dimensional flow channel on the sketch according to the extracted flow channel and marking the dimensions, then using the Surface From Skretches module to turn the previously drawn two-dimensional flow channel from a line segment into a surface on the sketch, then establishing a similar sketch, then using the Line function to show the line segments used to divide the flow channel on the sketch, and using the Projection function to complete the flow channel division, then importing the divided two-dimensional flow channel model into the Mesh module, and then using the Face Meshing function to establish the mesh size on the imported two-dimensional flow channel surface diagram to complete the two-dimensional flow channel mesh drawing, so as to obtain the flow channel simulation model.

[0032] The inlets of the upper inlet pipe and the lower inlet pipe are set as the inlet surface, and the outlets of the upper outlet pipe and the lower outlet pipe are set as the outlet surface; the surfaces in contact with the optical rod in the left rod cavity and the right rod cavity are all insulating surfaces, named adiabat; the bottom surfaces of the lower inlet pipe, the central gas chamber, and the lower outlet pipe are all set as the heating surface, named heat, and the top surface of the central gas chamber is set as the heating surface, named heat; the part of the upper inlet pipe corresponding to the lower inlet pipe up and down is the upper left horizontal pipe, the part of the upper outlet pipe corresponding to the lower outlet pipe up and down is the upper right horizontal pipe, and the top surfaces of the upper left horizontal pipe and the upper right horizontal pipe are all set as the heating surface, named heat; the central axis is named middle.

[0033] The inlet of the upper inlet pipe is connected to the inlet end of the upper left horizontal pipe located below the inlet through an L-shaped pipe, the outlet of the upper outlet pipe is connected to the outlet end of the upper right horizontal pipe located below the outlet through an L-shaped pipe, and the surfaces on the L-shaped pipe are all named wall.

[0034] The established grid size refers to: multiple square grids with a side length of 1 mm are established on the central gas chamber, and the heights of the inlet surface and the outlet surface are respectively drawn with 5 grid edges. The lengths of the horizontal part and the vertical part in the L-shaped pipe are respectively drawn with 30 grid edges and 50 grid edges. The lengths of the upper left horizontal pipe, the lower inlet pipe, the lower outlet pipe, and the upper right horizontal pipe are all drawn with 70 grid edges.

[0035] In the second step, the heating simulation means that after obtaining the flow channel simulation model, first update the mesh in Workbench of Ansys software, then open the Fluent module, and then perform mesh inspection. After the mesh quality inspection is qualified, open the Energy function and make the following settings: select the default gas in the fluid material, set the inlet temperature to 273 - 323 K, the inlet velocity to 0.1 m / s, and the pressure to standard atmospheric pressure in the boundary condition settings. At the same time, the heating surface is treated with a constant wall temperature, and the heating temperature is set to 800 - 2000 K. The heat transfer settings of the adiabat surface and the wall surface are set to 0, set a reasonable simulation algorithm, and set the monitoring residual convergence criteria to 10 -6 , select the calculation area as all zone, perform initialization, set the initial temperature of the central gas chamber to 273 - 323 K, and arrange at least 500 calculation points; then calculate the residuals. From the residual diagram, it can be seen that if all parameters have reached convergence, then view the temperature distribution diagram of the central gas chamber in the heating simulation results, and view the temperature distribution of each point on the central axis.

[0036] After viewing the temperature distribution diagram of the central gas chamber and viewing the temperature distribution of each point on the central axis, perform any one or any combination of the following operations:

[0037] Calculate the temperature distribution under different inlet flow velocities;

[0038] Repeat the previous operation process and set it to unsteady state. Subsequently, in addition to obtaining the above content corresponding to the operation process, calculate the time required to reach steady state.

[0039] In the second step, the gas transportation simulation means that after obtaining the flow channel simulation model, first update the mesh in Workbench of Ansys software, then open the Fluent module, and then perform mesh inspection. After the mesh quality inspection is qualified, set the gravitational acceleration to -9.81 m / s² in the Y-axis direction, then turn on the Energy function and make the following settings: turn on Species, select the mixture for the gas material, and this mixture includes the gas to be measured and the remaining gases. In the boundary condition settings, set the heating temperature to above 873 K, the inlet velocity to 0.1 m / s, the inlet temperature to 273 - 323 K, initialize the central gas chamber, the initial temperature of the central gas chamber is 273 - 323 K, the concentration of the gas to be measured in the central gas chamber is 0, and arrange at least 500 calculation points; then calculate the residuals. It can be seen from the residual graph that if all parameters have reached convergence, then view the gas concentration distribution map of the central gas chamber in the results of the gas transportation simulation, and view the gas concentrations at each point on the central axis.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] 1. In the method for judging the temperature and component concentration uniformity in a high-temperature gas cell of the present invention, it successively experiences the steps of establishing a flow channel simulation model, simulating and accepting the simulation model, obtaining the simulated absorbance, obtaining the experimental absorbance, and finally judging the uniformity. Generally speaking, first obtain a flow channel simulation model that meets the temperature and component concentration uniformity, and obtain the simulated temperature and component concentration data. Then, based on the flow channel simulation model, manufacture the actual flow channel, and then under the same conditions as the previous simulation in the actual flow channel, conduct experiments to obtain the experimental temperature and component concentration data. Finally, compare the simulated data with the experimental data to ultimately judge the temperature and component concentration uniformity. Compared with the prior art, it not only greatly shortens the operation time and operation procedures, saves manpower and material resources, but also can combine simulation with experiment, greatly improving the accuracy of judgment. Generally speaking, this design is simple, efficient, and low-cost. It only needs to perform numerical calculations and experimental verification to judge whether the design of the gas cell can achieve uniform temperature and gas component concentration distribution, and provide a numerical criterion for the optimization of the gas cell. Therefore, the present invention not only has a relatively simple judgment process and low cost, but also is easy to operate and has high accuracy.

[0042] 2. In the method for judging the temperature and component concentration uniformity in a high-temperature gas cell according to the present invention, whether in the simulation stage or in the final experimental stage, the uniformity judgment of these two types of parameters, namely temperature and gas component concentration, can be carried out simultaneously. The same flow channel simulation model is used, which not only has strong functionality and expands the application range, but also reduces the judgment cost. In addition, the two types of parameters can be compared with each other to further improve the accuracy. Therefore, the present invention not only has high accuracy but also strong functionality.

[0043] 3. In the method for judging the temperature and component concentration uniformity in a high-temperature gas cell according to the present invention, in the step of obtaining the experimental absorbance, the on-site laser absorption test and the gas spectrum measurement are carried out in the actually constructed high-temperature gas cell, and the judgment is carried out in combination with the process during the experiment, which is more in line with the actual situation and has high accuracy. Especially compared with the defect that it is difficult to judge the on-site uniformity in a high-temperature gas cell in the prior art, it is more superior. Therefore, the present invention has high accuracy and stronger practicability.

[0044] 4. In the method for judging the temperature and component concentration uniformity in a high-temperature gas cell according to the present invention, the test object is gas, which can be either a single-component gas or a multi-component mixed gas, so as to be applicable to the design of burners with different geometric sizes and the design and simulation of the combustion systems where they are located. It can give a more accurate feedback on the gas situation in the combustion result to the burner or combustion system, and thus facilitate the improvement of the design effect. Therefore, the present invention has high accuracy and is conducive to improving the design quality of the burner or combustion system. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the operation process of the present invention.

[0046] Figure 2 It is a three-dimensional structure schematic diagram of the extracted flow channel in the present invention.

[0047] Figure 3 It is a schematic diagram of the structure of the two-dimensional flow channel in the present invention.

[0048] Figure 4 It is Figure 3 After establishing the grid size on it, that is, the structure schematic diagram of the flow channel simulation model.

[0049] Figure 5 It is a schematic diagram of the markings on each surface of the flow channel simulation model in the present invention.

[0050] Figure 6 It is a temperature distribution diagram of the central gas chamber in Embodiment 4 of the present invention.

[0051] Figure 7 It is the temperature distribution of each point on the central axis of the central gas chamber in Embodiment 4 of the present invention.

[0052] Figure 8 It is the gas concentration distribution diagram of the central gas chamber in Embodiment 5 of the present invention.

[0053] Figure 9 It is the gas concentration at each point on the central axis of the central gas chamber in Embodiment 5 of the present invention.

[0054] Figure 10 It is a schematic diagram in the negative Y-axis direction in Embodiment 5 of the present invention.

[0055] Figure 11 It is a schematic structural diagram of the measurement system where the photodetector of the present invention is located.

[0056] In the figure: lower intake pipe 1, upper intake pipe 2, upper left horizontal pipe 21, central gas chamber 3, central axis 31, lower outlet pipe 4, upper outlet pipe 5, upper right horizontal pipe 51, left rod cavity 6, right rod cavity 7, L-shaped pipe 8, horizontal part 81, vertical part 82, photodetector 9, function generator 91, laser controller 92, laser 93, collimator 94, multi-pass gas cell 95, data acquisition card 96, data post-processing program 97, result display element 98, cylindrical structure 10, cylindrical cavity 101. Specific embodiments

[0057] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0058] See Figure 1 — Figure 11 , a method for judging the temperature and component concentration uniformity in a high-temperature gas cell, comprising the following steps:

[0059] The first step, the step of establishing a flow channel simulation model: Establish a two-dimensional model of the flow channel in the high-temperature gas cell in a finite element analysis software to obtain a flow channel simulation model. The flow channel simulation model includes an upper intake pipe 2, a lower intake pipe 1, a central gas chamber 3, an upper outlet pipe 5, and a lower outlet pipe 4, all of which are hollow structures. The middle part along the axial direction inside the central gas chamber 3 is the central axis 31. The left end of the central gas chamber 3 is respectively connected to the air outlets of the upper intake pipe 2 and the lower intake pipe 1, and the right end of the central gas chamber 3 is respectively connected to the air inlets of the upper outlet pipe 5 and the lower outlet pipe 4. The upper intake pipe 2, the left end of the central gas chamber 3, and the lower intake pipe 1 together enclose a left rod cavity 6 for inserting and fitting with an optical rod. The upper outlet pipe 5, the right end of the central gas chamber 3, and the lower outlet pipe 4 together enclose a right rod cavity 7 for inserting and fitting with an optical rod. Moreover, the top and bottom surfaces of the central gas chamber 3 are both heating surfaces;

[0060] Step 2, simulation acceptance steps of the simulation model: First, perform heating simulation and gas transportation simulation on the runner simulation model respectively, and then perform temperature acceptance judgment and concentration acceptance judgment based on the simulation results respectively. If both acceptance judgments pass, the simulation model is qualified;

[0061] The temperature acceptance judgment refers to: checking the temperature distribution map of the central gas chamber 3 in the result of the heating simulation, and checking the temperature distribution of each point on the central axis 31. If the temperature distribution map shows uniform distribution and the temperature difference of each point on the central axis 31 ≤ 2K, the judgment passes;

[0062] The concentration acceptance judgment refers to: checking the gas concentration distribution map of the central gas chamber 3 in the result of the gas transportation simulation, and checking the gas concentration of each point on the central axis 31. If the gas concentration distribution map shows uniform distribution and the mass fraction difference of each point on the central axis 31 ≤ 2%, the judgment passes;

[0063] Step 3, steps for obtaining simulated absorbance: First, determine the optical path and the target gas, and then determine the simulated temperature and simulated concentration respectively based on the temperature and concentration of each point on the central axis 31 in the above simulation results. Then, perform calculations respectively based on the simulated temperature and simulated concentration to obtain the simulated absorbance of temperature and the simulated absorbance of concentration correspondingly; the simulated temperature is the maximum value, minimum value or average value of the temperatures of each point on the central axis 31, and the simulated concentration is the maximum value, minimum value or average value of the concentrations of each point on the central axis 31;

[0064] Step 4, steps for obtaining experimental absorbance: First, establish an actual gas cell, and the structure of the runner in this actual gas cell is the same as that of the above simulation model. Then, use the same optical path, target gas, temperature or concentration as those in the above process of obtaining simulated absorbance for the actual gas cell. Then, introduce the scanning laser that will be absorbed by the target gas through the optical rod, and then detect the absorption signal and perform limit fitting through the photodetector 9 to obtain the experimental absorbance of temperature and the experimental absorbance of concentration correspondingly;

[0065] Step 5, final uniformity judgment steps: Compare the simulated absorbance of temperature and the experimental absorbance of temperature. At the same time, compare the simulated absorbance of concentration and the experimental absorbance of concentration. If the simulated absorbance of temperature and the experimental absorbance of temperature are basically the same, and the simulated absorbance of concentration and the experimental absorbance of concentration are basically the same, it is determined that the temperature and the gas component concentration in the actual gas cell are both uniform.

[0066] The simulated absorbance of temperature and the experimental absorbance of temperature being basically the same means that after comparison, the result is a curve, and the temperature difference of each point on this curve ≤ 2K, then it is basically the same;

[0067] The fact that the simulated absorbance at the said concentration and the experimental absorbance at the said concentration are basically the same means that: after comparison, the result of the comparison is a single curve, and the mass fraction difference at each point on this curve ≤ 2%, then it is basically the same.

[0068] The fact that the said two are compared means that: based on the absorbance peak spectral signals selected from the simulated absorbance at temperature, the experimental absorbance at temperature, the simulated absorbance at concentration, and the experimental absorbance at concentration, and substituting them into any of the following functions for solution:

[0069] The first type:

[0070]

[0071] where n is the number of selected wave peaks, kf is the k-th wave peak, αkf is the corresponding absorbance peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value;

[0072] The second type:

[0073]

[0074] wherein, n is the number of selected wave peaks, kf is the k-th wave peak, αkf is the corresponding absorbance peak value, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value;

[0075] The third type:

[0076]

[0077] where n is the number of selected wave peaks, kf is the k-th wave peak, Akf is the corresponding integrated absorbance peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value;

[0078] The fourth type:

[0079]

[0080] where n is the number of selected wave peaks, kf is the k-th wave peak value, αkf is the corresponding absorbance peak value, Akf is the corresponding integrated absorbance peak value, ν0 is the central wave number of the laser, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value.

[0081] In the first step, establishing a two-dimensional model of the flow channel in the high-temperature gas pool in the finite element analysis software to obtain the flow channel simulation model means: first establishing a Solidworks model of the high-temperature gas pool, then importing it into the finite element analysis software, namely the DesignModeler module in Ansys software, then observing the shape of the flow channel in the high-temperature gas pool, then selecting the air inlet and the air outlet, then extracting the flow channel from the high-temperature gas pool, then calling the Designmodeler function under the Fluid Flow function in Ansys to establish a sketch, and then drawing the two-dimensional flow channel on the sketch according to the extracted flow channel and marking the dimensions, then using the Surface From Skretches module to turn the previously drawn two-dimensional flow channel from a line segment into a surface on the sketch, then establishing a same sketch, and then using the Line function on the sketch to show each line segment used to divide the flow channel, and using the Projection function to complete the division of the flow channel, then importing the divided two-dimensional flow channel model into the Mesh module, and then using the Face Meshing function to establish the mesh size on the imported two-dimensional flow channel surface diagram to complete the drawing of the two-dimensional flow channel mesh, so as to obtain the flow channel simulation model.

[0082] The air inlets of the upper air inlet pipe 2 and the lower air inlet pipe 1 are set as the inlet surface, and the air outlets of the upper air outlet pipe 5 and the lower air outlet pipe 4 are set as the outlet surface; the surfaces in contact with the optical rod in the left rod cavity 6 and the right rod cavity 7 are all insulating surfaces, named adiabat; the bottom surfaces of the lower air inlet pipe 1, the central air chamber 3, and the lower air outlet pipe 4 are all set as heating surfaces, named heat, and the top surface of the central air chamber 3 is set as a heating surface, named heat; the part of the upper air inlet pipe 2 corresponding to the lower air inlet pipe 1 up and down is the upper left horizontal pipe 21, the part of the upper air outlet pipe 5 corresponding to the lower air outlet pipe 4 up and down is the upper right horizontal pipe 51, and the top surfaces of the upper left horizontal pipe 21 and the upper right horizontal pipe 51 are all set as heating surfaces, named heat; the central axis 31 is named middle.

[0083] The air inlet of the upper air inlet pipe 2 is connected to the air inlet end of the upper left horizontal pipe 21 located below the air inlet through the L-shaped pipe 8, the air outlet of the upper air outlet pipe 5 is connected to the air outlet end of the upper right horizontal pipe 51 located below the air outlet through the L-shaped pipe 8, and the surfaces on the L-shaped pipe 8 are all named wall.

[0084] Establishing the mesh size means: establishing a plurality of square meshes with a side length of 1 mm on the central air chamber 3, corresponding to drawing 5 mesh sides for the heights of the inlet surface and the outlet surface, corresponding to drawing 30 mesh sides and 50 mesh sides respectively for the lengths of the horizontal part 81 and the vertical part 82 in the L-shaped pipe 8, and corresponding to drawing 70 mesh sides for the lengths of the upper left horizontal pipe 21, the lower air inlet pipe 1, the lower air outlet pipe 4, and the upper right horizontal pipe 51.

[0085] In the second step, the heating simulation means that after obtaining the runner simulation model, first update the mesh in Workbench of Ansys software, then open the Fluent module, and then perform a mesh check. After the mesh quality check is qualified, open the Energy function and make the following settings: select the default gas in the fluid material, set the inlet temperature to 273 - 323 K, the inlet velocity to 0.1 m / s, and the pressure to standard atmospheric pressure in the boundary condition settings. At the same time, the heating surface is treated with a constant wall temperature, and the heating temperature is set to 800 - 2000 K. The heat transfer settings for the adiabat surface and the wall surface are set to 0. Set a reasonable simulation algorithm and set the monitoring residual convergence criteria to 10 -6 , select the calculation region as all zone, perform initialization, set the initial temperature of the central chamber 3 to 273 - 323 K, and arrange at least 500 calculation points; then calculate the residuals. From the residual diagram, it can be seen that if all parameters have reached convergence, then view the temperature distribution diagram of the central chamber 3 in the heating simulation results, and view the temperature distribution of each point on the central axis 31.

[0086] After viewing the temperature distribution diagram of the central chamber 3 and the temperature distribution of each point on the central axis 31, perform any one or any combination of the following operations:

[0087] Calculate the temperature distribution under different inlet flow rates;

[0088] Repeat the previous operation process and set it to unsteady state. Subsequently, in addition to obtaining the above content corresponding to the operation process, calculate the time required to reach the steady state.

[0089] In the second step, the gas transportation simulation means that after obtaining the runner simulation model, first update the mesh in Workbench of Ansys software, then open the Fluent module, and then perform a mesh check. After the mesh quality check is qualified, set the gravitational acceleration to -9.81 m / s² in the Y-axis direction, then open the Energy function and make the following settings: open Species, select the mixture as the gas material, and this mixture includes the gas to be measured and the remaining gases. Set the heating temperature to above 873 K, the inlet velocity to 0.1 m / s, the inlet temperature to 273 - 323 K in the boundary condition settings, initialize the central chamber 3, the initial temperature of the central chamber 3 is 273 - 323 K, and the concentration of the gas to be measured in the central chamber 3 is 0. Arrange at least 500 calculation points; then calculate the residuals. From the residual diagram, it can be seen that if all parameters have reached convergence, then view the gas concentration distribution diagram of the central chamber 3 in the gas transportation simulation results, and view the gas concentration of each point on the central axis 31.

[0090] The principle of the present invention is described as follows:

[0091] In the present invention, "first determine the optical path and gas components, and then determine respectively based on the temperature and concentration data on the central axis in the above simulation results" means that when judging the temperature uniformity, whether obtaining the simulated absorbance or the experimental absorbance, the participation of gas is required, generally air. When judging the uniformity of the gas component concentration, whether obtaining the simulated absorbance or the experimental absorbance, the participation of gas is also required, and it is a mixed gas, and the types of gas are not limited. Generally, one of them is air, and the rest of the gas is the gas to be measured.

[0092] The simulated absorbance of the temperature and the simulated absorbance of the concentration obtained in the present invention both present as a curve, rather than a unique value.

[0093] In the present invention, after calculating the residual, it can be known from the residual plot whether it converges. If it does not reach convergence, improve the grid quality and repeat the above operations until all parameters have reached convergence.

[0094] "The flow channel simulation model in the present invention includes an upper intake pipe 2, a lower intake pipe 1, a central gas chamber 3, an upper outlet pipe 5 and a lower outlet pipe 4, all of which are hollow structures" means that the flow channel simulation model is a hollow cylindrical structure 10. A cylindrical cavity 101 is provided inside the cylindrical structure 10. An optical rod is axially inserted into each of the left and right ends of the cylindrical cavity 101. The space occupied by the optical rod is the left rod cavity 6 or the right rod cavity 7. The parts on the left end of the cylindrical cavity 101 located at the top and bottom of the left rod cavity 6 are the upper intake pipe 2 and the lower intake pipe 1 (the cross-section of the pipe is arc-shaped). The parts on the right end of the cylindrical cavity 101 located at the top and bottom of the right rod cavity 7 are the upper outlet pipe 5 and the lower outlet pipe 4 (the cross-section of the pipe is arc-shaped).

[0095] The output end of the function generator 91 in the present invention is connected to one end of the laser controller 92. The other end of the laser controller 92 is connected to the input end of the laser 93. The output end of the laser 93 is optically connected to one end of the collimator 94. The other end of the collimator 94 is optically connected to the outer end of the optical rod in the left rod cavity 6. The inner end of the optical rod is in contact with the left end of the central gas chamber 3. The right end of the central gas chamber 3 is in contact with the left end of the optical rod in the right rod cavity 7. The outer end of the optical rod is optically connected to one end of the photodetector 9. The other end of the photodetector 9 is connected to one end of the data acquisition card 96. The other end of the data acquisition card 96 is connected to the input end of the data post-processing program 97. The output end of the data post-processing program 97 is connected to the result display element 98.

[0096] Example 1:

[0097] SeeFigure 1 — Figure 5 , and Figure 11 , a method for judging the uniformity of temperature and component concentration in a high-temperature gas pool, comprising the following steps:

[0098] The first step, the step of establishing a flow channel simulation model: Establish a two-dimensional model of the flow channel in the high-temperature gas pool in finite element analysis software to obtain a flow channel simulation model. The flow channel simulation model includes an upper inlet pipe 2, a lower inlet pipe 1, a central gas chamber 3, an upper outlet pipe 5, and a lower outlet pipe 4, all of which are hollow structures. The middle part along the axial direction of the central gas chamber 3 and located in the middle is the central axis 31. The left end of the central gas chamber 3 is respectively connected to the air outlets of the upper inlet pipe 2 and the lower inlet pipe 1, and the right end of the central gas chamber 3 is respectively connected to the air inlets of the upper outlet pipe 5 and the lower outlet pipe 4. The upper inlet pipe 2, the left end of the central gas chamber 3, and the lower inlet pipe 1 together enclose a left rod cavity 6 for inserting and cooperating with an optical rod. The upper outlet pipe 5, the right end of the central gas chamber 3, and the lower outlet pipe 4 together enclose a right rod cavity 7 for inserting and cooperating with an optical rod. Moreover, the top surface and the bottom surface of the central gas chamber 3 are both heating surfaces;

[0099] The second step, the step of simulating and accepting the simulation model: First, perform heating simulation and gas transportation simulation on the flow channel simulation model respectively, and then perform temperature acceptance judgment and concentration acceptance judgment respectively according to the simulation results. If both acceptance judgments pass, the simulation model is qualified;

[0100] The temperature acceptance judgment refers to: View the temperature distribution map of the central gas chamber 3 in the result of the heating simulation, and view the temperature distribution of each point on the central axis 31. If the temperature distribution map shows a uniform distribution and the temperature difference between each point on the central axis 31 ≤ 2K, the judgment passes;

[0101] The concentration acceptance judgment refers to: View the gas concentration distribution map of the central gas chamber 3 in the result of the gas transportation simulation, and view the gas concentration of each point on the central axis 31. If the gas concentration distribution map shows a uniform distribution and the mass fraction difference between each point on the central axis 31 ≤ 2%, the judgment passes;

[0102] The third step, the step of obtaining the simulation absorbance: First, determine the optical path and the target gas, then determine the simulation temperature and the simulation concentration respectively according to the temperature and concentration of each point on the central axis 31 in the above simulation results, and then perform calculations respectively according to the simulation temperature and the simulation concentration to correspondingly obtain the simulation absorbance of temperature and the simulation absorbance of concentration; The simulation temperature is the maximum value, the minimum value or the average value of the temperatures of each point on the central axis 31, and the simulation concentration is the maximum value, the minimum value or the average value of the concentrations of each point on the central axis 31;

[0103] Fourth step, steps for obtaining experimental absorbance: First, establish an actual gas cell. The structure of the flow channel in this actual gas cell is the same as that of the above simulation model. Then, use the same optical path, target gas, temperature, or concentration for the actual gas cell as those in the above process for obtaining simulation absorbance. Next, introduce the scanning laser that will be absorbed by the target gas through an optical rod, and then detect the absorption signal through a photodetector 9 and perform limit fitting to correspondingly obtain the experimental absorbance of temperature and the experimental absorbance of concentration.

[0104] Fifth step, steps for judging the final uniformity: Compare the simulation absorbance of temperature with the experimental absorbance of temperature. At the same time, compare the simulation absorbance of concentration with the experimental absorbance of concentration. If the simulation absorbance of temperature and the experimental absorbance of temperature are basically the same, and the simulation absorbance of concentration and the experimental absorbance of concentration are basically the same, it is determined that the temperature and the concentration of the gas components in the actual gas cell are both uniform.

[0105] Among them, it is preferably that the simulation absorbance of temperature and the experimental absorbance of temperature are basically the same means that: after comparison, the result is a curve, and the temperature difference at each point on this curve ≤ 2K, then it is basically the same; at the same time, it is preferably that the simulation absorbance of concentration and the experimental absorbance of concentration are basically the same means that: after comparison, the result is a curve, and the mass fraction difference at each point on this curve ≤ 2%, then it is basically the same.

[0106] Example 2:

[0107] The basic content is the same as that of Example 1, except that:

[0108] The so-called "after comparison" between the two means that:

[0109] Based on the selected absorbance peak spectral signals among the simulation absorbance of temperature, the experimental absorbance of temperature, the simulation absorbance of concentration, and the experimental absorbance of concentration, and substitute them into any of the following functions for solution:

[0110] The first type:

[0111]

[0112] n is the number of selected wave peaks, kf is the kth wave peak, αkf is the corresponding absorbance peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value;

[0113] The second type:

[0114]

[0115] Among them, n is the number of selected wave peaks, kf is the kth wave peak, αkf is the corresponding absorbance peak value, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value;

[0116] The third type:

[0117]

[0118] where n is the number of selected wave peaks, kf is the k-th wave peak, Akf is the corresponding integral absorbance wave peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value;

[0119] The fourth type:

[0120]

[0121] where n is the number of selected wave peaks, kf is the k-th wave peak value, αkf is the corresponding absorbance wave peak value, Akf is the corresponding integral absorbance wave peak value, ν0 is the central wave number of the laser, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulation value.

[0122] Example 3:

[0123] The basic content is the same as that of Example 1, except that:

[0124] In the first step, establishing a two-dimensional model of the flow channel in the high-temperature gas cell in the finite element analysis software to obtain the flow channel simulation model means:

[0125] First, establish a Solidworks model of the high-temperature gas pool, and then import it into the finite element analysis software, namely the DesignModeler module in Ansys software. Then, observe the shape of the flow channel in the high-temperature gas pool, select the inlet and outlet, and then extract the flow channel from the high-temperature gas pool. Next, call the Designmodeler function under the Fluid Flow function in Ansys to create a sketch. Then, based on the extracted flow channel on the sketch, draw a two-dimensional flow channel and mark the dimensions. Then, use the Surface From Skretches module to turn the previously drawn two-dimensional flow channel from a line segment into a surface on the sketch. Then, create a similar sketch, and on the sketch, use the Line function to show the line segments used to divide the flow channel, and use the Projection function to complete the division of the flow channel. Then, import the divided two-dimensional flow channel model into the Mesh module, and then use the FaceMeshing function to set the mesh size on the imported two-dimensional flow channel surface diagram to complete the drawing of the two-dimensional flow channel mesh, thereby obtaining a flow channel simulation model. In this flow channel simulation model, the inlets of the upper inlet pipe 2 and the lower inlet pipe 1 are set as the inlet surface, and the outlets of the upper outlet pipe 5 and the lower outlet pipe 4 are set as the outlet surface; the surfaces in contact with the optical rod in the left rod cavity 6 and the right rod cavity 7 are all insulating surfaces, named adiabat; the bottom surfaces of the lower inlet pipe 1, the central gas chamber 3, and the lower outlet pipe 4 are all set as heating surfaces, named heat, and the top surface of the central gas chamber 3 is set as a heating surface, named heat; the part of the upper inlet pipe 2 corresponding to the lower inlet pipe 1 up and down is the upper left horizontal pipe 21, the part of the upper outlet pipe 5 corresponding to the lower outlet pipe 4 up and down is the upper right horizontal pipe 51, and the top surfaces of the upper left horizontal pipe 21 and the upper right horizontal pipe 51 are all set as heating surfaces, named heat; the central axis 31 is named middle.

[0126] Example 4:

[0127] The basic content is the same as that of Example 3, except that:

[0128] The heating simulation refers to:

[0129] After obtaining the flow channel simulation model, first update the mesh in Workbench in Ansys software, then open the Fluent module, and then perform a mesh check. After the mesh quality check is qualified, open the Energy function and make the following settings:

[0130] Select the default gas in the fluid material. In the boundary condition settings, set the inlet temperature to 273 - 323 K (preferably 300 K), the inlet velocity to 0.1 m / s, and the pressure to standard atmospheric pressure. At the same time, the heating surface is treated with a constant wall temperature, and the heating temperature is set to 800 - 2000 K (preferably 800 K). The heat transfer of the adiabat surface and the wall surface is set to 0. Set a reasonable simulation algorithm, and set the monitoring residual convergence criteria to 10 -6 , select the calculation area as all zone, initialize, set the initial temperature of the central gas chamber 3 to 273 - 323 K (preferably 300 K), and arrange at least 500 calculation points (preferably 1000 calculation points);

[0131] Then calculate the residuals. It can be seen from the residual diagram that if all parameters have reached convergence, then view the temperature distribution diagram of the central gas chamber 3 in the heating simulation results (see Figure 6 ), and view the temperature distribution of each point on the central axis 31 (see Figure 7 ).

[0132] Example 5:

[0133] The basic content is the same as that of Example 3, the difference is:

[0134] After obtaining the flow channel simulation model, first update the mesh in Workbench of Ansys software, then open the Fluent module, and then perform a mesh check. After the mesh quality check is qualified, set the gravitational acceleration to -9.81 m / s² in the Y-axis direction (see Figure 10 ), then turn on the Energy function and make the following settings:

[0135] Open Species, select the gas material as a mixture, which includes the gas to be measured (preferably methane) and the remaining gas (preferably air). In the boundary condition settings, set the heating temperature to above 873 K (preferably 1373 K), the inlet velocity to 0.1 m / s, the inlet temperature to 273 - 323 K (preferably 300 K), the methane content (mass percentage concentration) at the initial entry into the gas chamber to 5%, initialize the central gas chamber 3, the initial temperature of the central gas chamber 3 is 273 - 323 K (preferably 300 K), the concentration of methane in the central gas chamber 3 is 0, and arrange at least 500 calculation points (preferably 1000 calculation points);

[0136] Then calculate the residuals. It can be seen from the residual diagram that if all parameters have reached convergence, then view the gas concentration distribution diagram of the central gas chamber 3 in the gas transmission simulation results (see Figure 8 ), and view the gas concentration of each point on the central axis 31 (see Figure 9 ).

[0137] The above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. Any equivalent modifications or changes made by those of ordinary skill in the art according to the disclosure of the present invention shall fall within the protection scope recorded in the claims.

Claims

1. A method for judging the temperature and component concentration uniformity in a high-temperature gas pool, characterized in that The judgment method includes the following steps: The first step, the step of establishing a flow channel simulation model: Establish a two-dimensional model of the flow channel in the high-temperature gas pool in finite element analysis software to obtain a flow channel simulation model. The flow channel simulation model includes an upper intake pipe (2), a lower intake pipe (1), a central gas chamber (3), an upper outlet pipe (5) and a lower outlet pipe (4), all of which are hollow structures. The middle part along the axial direction and in the middle of the central gas chamber (3) is the central axis (31). The left end of the central gas chamber (3) is respectively connected to the air outlets of the upper intake pipe (2) and the lower intake pipe (1), and the right end of the central gas chamber (3) is respectively connected to the air inlets of the upper outlet pipe (5) and the lower outlet pipe (4). The upper intake pipe (2), the left end of the central gas chamber (3), and the lower intake pipe (1) together enclose a left rod cavity (6) for inserting and mating with an optical rod. The upper outlet pipe (5), the right end of the central gas chamber (3), and the lower outlet pipe (4) together enclose a right rod cavity (7) for inserting and mating with an optical rod. And the top and bottom surfaces of the central gas chamber (3) are both heating surfaces; The second step, the step of simulating and accepting the simulation model: First, perform heating simulation and gas transmission simulation on the flow channel simulation model respectively, and then perform temperature acceptance judgment and concentration acceptance judgment respectively according to the simulation results. If both acceptance judgments pass, the simulation model is qualified; The temperature acceptance judgment refers to: Check the temperature distribution map of the central gas chamber (3) in the heating simulation result, and check the temperature distribution of each point on the central axis (31). If the temperature distribution map shows uniform distribution and the temperature difference of each point on the central axis (31) ≤ 2K, the judgment passes; The concentration acceptance judgment refers to: Check the gas concentration distribution map of the central gas chamber (3) in the gas transmission simulation result, and check the gas concentration of each point on the central axis (31). If the gas concentration distribution map shows uniform distribution and the mass fraction difference of each point on the central axis (31) ≤ 2%, the judgment passes; The third step, the step of obtaining the simulation absorbance: First, determine the optical path and the target gas, and then determine the simulation temperature and simulation concentration according to the temperature and concentration of each point on the central axis (31) in the above simulation results respectively. Then, perform calculations according to the simulation temperature and simulation concentration to obtain the simulation absorbance of temperature and the simulation absorbance of concentration respectively. The simulation temperature is the maximum value, minimum value or average value of the temperatures of each point on the central axis (31), and the simulation concentration is the maximum value, minimum value or average value of the concentrations of each point on the central axis (31); The fourth step, the step of obtaining the experimental absorbance: First, establish an actual gas pool. The structure of the flow channel in the actual gas pool is the same as that of the above simulation model. Then, use the same optical path, target gas, temperature or concentration as those in the above obtaining the simulation absorbance for the actual gas pool. Then, introduce a scanning laser that will be absorbed by the target gas through the optical rod, and then detect the absorption signal and perform limit fitting through a photodetector (9) to obtain the experimental absorbance of temperature and the experimental absorbance of concentration respectively; Step 5, the determination step of final uniformity: Compare the simulated absorbance of temperature with the experimental absorbance of temperature, and at the same time, compare the simulated absorbance of concentration with the experimental absorbance of concentration. If the simulated absorbance of temperature is basically the same as the experimental absorbance of temperature, and the simulated absorbance of concentration is basically the same as the experimental absorbance of concentration, it is determined that the temperature and the concentration of gas components in the actual gas cell are both uniform.

2. The method for judging the temperature and component concentration uniformity in a high-temperature gas pool according to claim 1, characterized in that: The fact that the simulated absorbance of temperature is basically the same as the experimental absorbance of temperature means that: After the two are compared, and the result of the comparison is a curve, and the temperature difference at each point on this curve ≤ 2K, then it is basically the same; The fact that the simulated absorbance of concentration is basically the same as the experimental absorbance of concentration means that: After the two are compared, and the result of the comparison is a curve, and the mass fraction difference at each point on this curve ≤ 2%, then it is basically the same.

3. The method for judging the temperature and component concentration uniformity in a high-temperature gas pool according to claim 2, characterized in that The fact that the two are compared means that: Based on the selected absorbance peak spectral signals in the simulated absorbance of temperature, the experimental absorbance of temperature, the simulated absorbance of concentration, and the experimental absorbance of concentration, substitute them into any of the following functions for solution: The first type: n is the number of selected wave peaks, kf is the kth wave peak, αkf is the corresponding absorbance peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value; The second type: Among them, n is the number of selected wave peaks, kf is the kth wave peak, αkf is the corresponding absorbance peak value, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value; The third type: Among them, n is the number of selected wave peaks, kf is the kth wave peak, Akf is the corresponding integrated absorbance peak value, ν0 is the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value; The fourth type: Among them, n is the number of selected wave peaks, kf is the kth wave peak value, αkf is the corresponding absorbance peak value, Akf is the corresponding integrated absorbance peak value, ν0 is the central wave number of the laser, ν is the wave number near the central wave number of the laser, exp represents the experimental value, and sim represents the simulated value.

4. The method for judging the temperature and component concentration uniformity in a high-temperature gas pool according to claim 1, 2 or 3, characterized in that: In the first step, the establishment of a two-dimensional model of the flow channel in the high-temperature gas cell in the finite element analysis software to obtain the flow channel simulation model means that: First, establish a Solidworks model of the high-temperature gas pool, and then import it into the finite element analysis software, namely the DesignModeler module in Ansys software. Then, observe the shape of the flow channel in the high-temperature gas pool, select the inlet and outlet, and then extract the flow channel from the high-temperature gas pool. Next, call the Designmodeler function under the Fluid Flow function in Ansys to create a sketch. Then, based on the extracted flow channel on the sketch, draw a two-dimensional flow channel and mark the dimensions. Then, use the SurfaceFrom Skretches module to turn the previously drawn two-dimensional flow channel from a line segment into a surface on the sketch. Then, create a similar sketch, and on the sketch, use the Line function to show the line segments used to divide the flow channel, and use the Projection function to complete the division of the flow channel. Then, import the divided two-dimensional flow channel model into the Mesh module, and then use the FaceMeshing function to set the mesh size on the imported two-dimensional flow channel surface diagram to complete the drawing of the two-dimensional flow channel mesh, thereby obtaining the flow channel simulation model.

5. The method for judging the temperature and component concentration uniformity in a high-temperature gas pool according to claim 4, characterized in that: The inlets of the upper inlet pipe (2) and the lower inlet pipe (1) are set as the inlet surface, and the outlets of the upper outlet pipe (5) and the lower outlet pipe (4) are set as the outlet surface; the surfaces in contact with the optical rod in the left rod cavity (6) and the right rod cavity (7) are all insulating surfaces, named adiabat. The bottom surfaces of the lower inlet pipe (1), the central gas chamber (3), and the lower outlet pipe (4) are all set as heating surfaces, and the top surface of the central gas chamber (3) is set as a heating surface. The part of the upper inlet pipe (2) corresponding to the lower inlet pipe (1) up and down is the upper left horizontal pipe (21), the part of the upper outlet pipe (5) corresponding to the lower outlet pipe (4) up and down is the upper right horizontal pipe (51), and the top surfaces of the upper left horizontal pipe (21) and the upper right horizontal pipe (51) are all set as heating surfaces. The central axis (31) is named middle.

6. The judgment method for the temperature and component concentration uniformity in a high-temperature gas pool according to claim 5, wherein: The inlet of the upper inlet pipe (2) is connected to the inlet end of the upper left horizontal pipe (21) located below the inlet through an L-shaped pipe (8), the outlet of the upper outlet pipe (5) is connected to the outlet end of the upper right horizontal pipe (51) located below the outlet through an L-shaped pipe (8), and the surfaces on the L-shaped pipe (8) are all named wall.

7. The judgment method for the temperature and component concentration uniformity in a high-temperature gas pool according to claim 6, wherein: The setting of the mesh size means: on the central gas chamber (3), multiple square meshes with a side length of 1 mm are established, 5 mesh sides are correspondingly drawn for the heights of the inlet surface and the outlet surface, 30 mesh sides and 50 mesh sides are respectively drawn for the lengths of the horizontal part (81) and the vertical part (82) in the L-shaped pipe (8), and 70 mesh sides are correspondingly drawn for the lengths of the upper left horizontal pipe (21), the lower inlet pipe (1), the lower outlet pipe (4), and the upper right horizontal pipe (51).

8. The judgment method for the temperature and component concentration uniformity in a high-temperature gas pool according to claim 5, wherein: In the second step, the heating simulation refers to: After obtaining the runner simulation model, first update the mesh in Workbench of Ansys software, then open the Fluent module, and then perform a mesh check. After the mesh quality check is qualified, open the Energy function and make the following settings: Select the default gas in the fluid material. In the boundary condition settings, set the inlet temperature to 273 - 323 K, the inlet velocity to 0.1 m / s, and the pressure to standard atmospheric pressure. At the same time, the heating surface is treated with a constant wall temperature, and the heating temperature is set to 800 - 2000 K. The heat transfer of the adiabat surface and the wall surface is set to 0. Set a reasonable simulation algorithm, and set the monitoring residual convergence criteria to 10 -6 , select the calculation area as allzone, initialize, set the initial temperature of the central gas chamber (3) to 273 - 323 K, and arrange at least 500 calculation points; Then calculate the residuals. As can be seen from the residual plot, if all parameters have converged, then view the temperature distribution map of the central chamber (3) in the heating simulation results, and view the temperature distribution of each point on the central axis (31).

9. The judgment method for the temperature and component concentration uniformity in a high-temperature gas pool according to claim 8, wherein: After viewing the temperature distribution map of the central chamber (3) and the temperature distribution of each point on the central axis (31), perform any one or any combination of the following operations: Calculate the temperature distribution at different inlet flow rates; Repeat the previous operation process and set it to unsteady state. Subsequently, in addition to obtaining the above content corresponding to the operation process, calculate the time required to reach the steady state.

10. The judgment method for the temperature and component concentration uniformity in a high-temperature gas pool according to claim 5, wherein: In the second step, the gas transportation simulation refers to: After obtaining the runner simulation model, first update the mesh in Workbench of Ansys software, then open the Fluent module, and then perform a mesh check. After the mesh quality check is qualified, set the gravitational acceleration to -9.81 m / s² in the Y-axis direction, then open the Energy function and make the following settings: Open Species, select the mixture for the gas material. This mixture includes the gas to be measured and the remaining gases. In the boundary condition settings, set the heating temperature to above 873 K, the inlet velocity to 0.1 m / s, the inlet temperature to 273 - 323 K, initialize the central chamber (3), the initial temperature of the central chamber (3) is 273 - 323 K, the concentration of the gas to be measured in the central chamber (3) is 0, and arrange at least 500 calculation points; Then calculate the residuals. As can be seen from the residual plot, if all parameters have converged, then view the gas concentration distribution map of the central chamber (3) in the gas transportation simulation results, and view the gas concentration of each point on the central axis (31).

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