阅读说明：本技术 一种多通道电弧等离子体源级联铜片水冷装置及其优化方法 (Multi-channel arc plasma source cascade copper sheet water cooling device and optimization method thereof ) 是由 艾昕 聂秋月 张仲麟 黄韬 于 2021-08-17 设计创作，主要内容包括：一种多通道电弧等离子体源级联铜片水冷装置及其优化方法。本发明涉及低温等离子体技术领域,所述装置包括：圆柱形铜片、钼环、密封圈、不锈钢管道；多个圆柱形铜片堆叠在一起形成级联铜片,钼环中间设有多通道级联电弧源的放电通道,钼环圆心距铜片圆心10mm,三个钼环互相呈120°放置,密封圈的圆心与铜片圆心重合,铜片内部存在水冷通道与外部的不锈钢管道相连接。本发明中提出的级联铜片水冷计算方法可以应用于任意结构的水冷通道,降低了级联铜片冷却效果的分析难度。本发明中提出的两种级联铜片水冷优化结构,相较于现有的水冷结构,铜片上密封圈位置的温度得到了降低,密封圈各位置的温度差异下降,冷却效率提高。(A multi-channel arc plasma source cascade copper sheet water cooling device and an optimization method thereof. The invention relates to the technical field of low-temperature plasma, and the device comprises: the device comprises a cylindrical copper sheet, a molybdenum ring, a sealing ring and a stainless steel pipeline; a plurality of cylindrical copper sheets are stacked together to form a cascade copper sheet, a discharge channel of a multi-channel cascade arc source is arranged in the middle of each molybdenum ring, the center of each molybdenum ring is 10mm away from the center of each copper sheet, the three molybdenum rings are mutually placed at an angle of 120 degrees, the center of each sealing ring is overlapped with the center of each copper sheet, and a water cooling channel is arranged in each copper sheet and connected with an external stainless steel pipeline. The water-cooling calculation method for the cascaded copper sheet can be applied to water-cooling channels with any structure, and the analysis difficulty of the cooling effect of the cascaded copper sheet is reduced. Compared with the existing water cooling structure, the two cascade copper sheet water cooling optimized structures provided by the invention have the advantages that the temperature of the position of the sealing ring on the copper sheet is reduced, the temperature difference of each position of the sealing ring is reduced, and the cooling efficiency is improved.)

1. A multi-channel arc plasma source cascade copper sheet water cooling device is characterized in that: the device comprises: the device comprises a cylindrical copper sheet, a molybdenum ring, a sealing ring and a stainless steel pipeline;

a plurality of cylindrical copper sheets are stacked together to form a cascade copper sheet, a discharge channel of a multi-channel cascade arc source is arranged in the middle of each molybdenum ring, the center of each molybdenum ring is 10mm away from the center of each copper sheet, the three molybdenum rings are mutually placed at an angle of 120 degrees, the center of each sealing ring is overlapped with the center of each copper sheet, and a water cooling channel is arranged in each copper sheet and connected with an external stainless steel pipeline.

2. The multi-channel arc plasma source cascade copper sheet water cooling device as claimed in claim 1, wherein: the diameter of the cylindrical copper sheet is 60mm, the thickness is 7mm, and the internal diameter of three molybdenum rings is 2mm, and the external diameter is 3 mm.

3. The multi-channel arc plasma source cascade copper sheet water cooling device as claimed in claim 2, wherein: the diameter of a discharge channel of the multichannel cascade arc source arranged in the middle of the molybdenum ring is 2 mm.

4. The multi-channel arc plasma source cascade copper sheet water cooling device as claimed in claim 3, wherein: the stainless steel pipeline comprises a water inlet stainless steel pipeline and a water outlet stainless steel pipeline, the two stainless steel pipelines and the cylindrical copper sheet are welded together at the position of the water cooling channel in a silver welding mode, the diameter of the position, connected with the cylindrical copper sheet, of each stainless steel pipeline is 4mm, and the diameter of the rest positions of the stainless steel pipelines is 5 mm.

5. A multi-channel arc plasma source cascade copper sheet water cooling device optimization method is based on the multi-channel arc plasma source cascade copper sheet water cooling device as claimed in claim 1, and is characterized in that:

the method is used for modeling the cooling process of the coupling solid heat transfer and the non-isothermal pipeline flow to the copper sheet, and the modeling process is represented by the following formula:

wherein u is the average fluid velocity of the cross section of the pipeline in the tangential direction of the central line, A is the cross-sectional area of the pipeline, rho is the density, p is the pressure, f is_DIs friction factor, Re is Reynolds number, e is pipe roughness, d is pipe diameter, and mu is viscosity coefficient; cp is constant pressure heat capacity, T is cooling water temperature, k is heat conductivity coefficient, Q_wallSource term T for heat exchange between water and copper sheet₂Is the copper electrode temperature; z is the perimeter of the pipe, h is the heat transfer coefficient, T_extIs the outside temperature of the pipe.

Technical Field

The invention relates to the technical field of low-temperature plasma, in particular to a multi-channel arc plasma source cascade copper sheet water cooling device and an optimization method thereof.

Background

The plasma is a non-binding macroscopic system consisting of electrons, positive and negative ions and neutral particles, and is a fourth state after three forms of solid, liquid and gas of substances. According to incomplete statistics, more than 99% of the substances which are proved to exist in a plasma situation, but because natural plasmas exist on the earth rarely, in order to pursue exploration and research of space plasmas, since the last 60 years, research work on laboratory plasma science is carried out, which becomes an important way for people to know plasmas, and the following modes are mainly adopted for generating plasmas in a laboratory: direct current discharge plasma, high frequency discharge plasma, radio frequency discharge plasma, microwave plasma, combustion, laser, ultraviolet, etc., and plasmas generated by various modes have different parameter ranges and different application fields.

The arc plasma source belongs to one of direct current arc discharge, and the generation thereof can trace back to 1956, a uniform and stable high-density plasma is generated by adopting a transferred arc discharge mode, and a plasma jet with large scale, stability, high ion flux (under the condition of axial magnetic field constraint) and high cleanliness can be generated under specific conditions. Compared with an arc plasma source, the cascade arc plasma source has the main characteristics that a middle-section neutral pole, namely a cascade copper sheet with a laminated structure and mutually insulated characteristics, is added besides the conventional anode and cathode, so that stable high-beam-current-density plasma is generated. Previous researches show that the diameter of a plasma beam generated by a single-channel cascade arc plasma source is usually about 2cm, which is difficult to meet the requirement of large-diameter plasma beams for many applications, for example, in the simulation of a near space plasma environment, the diameter of the plasma beam is required to be larger in order to ensure that the plasma has a better coating effect on a blunt body, and the diameter of the plasma beam is required to be about 10cm in the simulated ITER high-heat-load plasma interacting with a first wall. Therefore, in order to increase the diameter of the plasma beam, a multi-channel cascade arc plasma source is used. The multi-channel cascade arc plasma source is mainly composed of a plurality of columnar cathodes (generally tungsten needles), a plurality of cascade copper plates and annular anodes, wherein the cascade copper plates are insulated from each other and are sequentially overlapped, the cathodes, the cascade copper plates and the anodes are cooled by cooling water in the discharging process, the plurality of cathodes are respectively connected with a plurality of independent power supplies, and the anodes are commonly grounded. High-frequency-to-direct-current voltage is applied between the cathode and the anode, and working gas is continuously introduced through the gas inlet in the discharging process, so that the working gas is heated, ionized and expanded by direct-current electric arc, and a high-stability plasma beam current is formed and is ejected from the anode nozzle under the action of an electric field and a high-voltage flow field.

Because the requirement on the working condition required by the operation of the multichannel cascade arc source is not high, the multichannel cascade arc source can work in a wider range of air pressure (1-1000Pa) and wider current (5-2000A) to realize discharge, the working gas has more types, can be most of inert gas or hydrogen, deuterium and the like, the electron temperature of the generated plasma is about 10000K, and the multichannel cascade arc source has the advantages of high electron density, high ionization degree, large ion flux and the like. Until now, experts and scholars at home and abroad apply the plasma window to various scientific research and production fields, for example, the plasma window can be formed by carrying out structural improvement on the plasma window, and the plasma window is widely applied to the fields of neutron beam welding, plasma fast valves, gas charge strippers and the like as an effective means for vacuum sealing; in addition, the cascade arc source can generate plasma beams with high energy density under certain conditions, and is already applied to the field of interaction between plasma and materials.

In summary, the multichannel cascade arc source can generate plasma beams with characteristics of high density, strong collision, large scale and sub-wavelength, the diameter can reach 10cm or more, the requirement of large-diameter plasma beams in the existing simulation experiment and application can be met, and the multichannel cascade arc source is widely applied to various fields. Under the condition that the temperature and the flow of cooling water entering water are constant, the multichannel cascade electric arc source has poor cooling effect on the cascade copper sheets when operating at high power, meanwhile, as the airtightness is ensured, rubber rings need to be placed between all the cascade copper sheets, the rubber rings are at high temperature due to the difference of the cooling effect of the cascade copper sheets, the temperature difference of all the positions of the rubber rings is large due to the existing cascade copper sheet water cooling design mode, the rubber rings are easy to age in the long-time discharging process, and the sealing performance of the multichannel cascade electric arc source is poor.

Disclosure of Invention

The invention aims to solve the problems that the cooling efficiency of the cascade copper sheet in the existing multichannel cascade arc source is not high, and the rubber ring for sealing is easy to age, and the technical scheme is as follows:

a multi-channel arc plasma source cascade copper sheet water cooling device comprises: the device comprises a cylindrical copper sheet, a molybdenum ring, a sealing ring and a stainless steel pipeline;

a plurality of cylindrical copper sheets are stacked together to form a cascade copper sheet, a discharge channel of a multi-channel cascade arc source is arranged in the middle of each molybdenum ring, the center of each molybdenum ring is 10mm away from the center of each copper sheet, the three molybdenum rings are mutually placed at an angle of 120 degrees, the center of each sealing ring is overlapped with the center of each copper sheet, and a water cooling channel is arranged in each copper sheet and connected with an external stainless steel pipeline.

Preferably, the diameter of the cylindrical copper sheet is 60mm, the thickness is 7mm, the inner diameter of the three molybdenum rings is 2mm, and the outer diameter is 3 mm.

Preferably, the diameter of a discharge channel of the multichannel cascade arc source arranged in the middle of the molybdenum ring is 2 mm.

Preferably, the stainless steel pipeline comprises a water inlet stainless steel pipeline and a water outlet stainless steel pipeline, the two stainless steel pipelines and the cylindrical copper sheet are welded together at the position of the water cooling channel in a silver welding mode, the diameter of the position, connected with the cylindrical copper sheet, of the two stainless steel pipelines is 4mm, and the rest positions are 5 mm.

A method for optimizing a multi-channel arc plasma source cascade copper sheet water cooling device is used for modeling a cooling process of a coupling solid heat transfer and non-isothermal pipeline flow to a copper sheet, and the modeling process is represented by the following formula:

wherein u is the average fluid velocity of the cross section of the pipeline in the tangential direction of the central line, A is the cross section area of the pipeline, ρ is the density, p is the pressure, fD is the friction factor, Re is the Reynolds number, e is the roughness of the pipeline, d is the diameter of the pipeline, and μ is the viscosity coefficient; cp is constant-pressure heat capacity, T is cooling water temperature, k is heat conductivity coefficient, and Qwall is copper electrode temperature of a source term T2 for heat exchange between water and a copper sheet; z is the circumference of the pipe, h is the heat transfer coefficient, and Text is the external temperature of the pipe.

The invention has the following beneficial effects:

the invention adopts a mode of combining diffusion welding and silver welding, so that the design of the water cooling channel of the multi-channel cascade arc plasma source and the copper sheet is not limited by the structure of the cascade copper sheet, and a cascade copper sheet cooling calculation method is designed by utilizing finite element simulation, so that the cooling of the water cooling channel with any structure can be calculated, and meanwhile, two water cooling structures are designed according to the calculation method, so that the cooling effect of the cascade copper sheet is improved compared with the traditional mode.

The invention provides a method for welding two copper sheets with water cooling grooves together by diffusion welding to form a cascade copper sheet with a water cooling channel inside.

The water-cooling calculation method for the cascaded copper sheet can be applied to water-cooling channels with any structure, and the analysis difficulty of the cooling effect of the cascaded copper sheet is reduced.

Compared with the existing water cooling structure, the two cascade copper sheet water cooling optimized structures provided by the invention have the advantages that the temperature of the position of the sealing ring on the copper sheet is reduced, the temperature difference of each position of the sealing ring is reduced, and the cooling efficiency is improved.

Drawings

FIG. 1 is an external structural view of a cascaded copper sheet;

FIG. 2 is an internal cross-sectional view of a cascaded copper sheet and the direction of cooling water flow;

FIG. 3 is an optimized water-cooling configuration;

FIG. 4 is an optimized water-cooling configuration;

FIG. 5 is a graph of temperature versus time obtained by three initial value setting methods;

FIG. 6 is a temperature change curve of three different positions of the cascaded copper sheet when the temperature of the inner wall of the molybdenum ring is set to different values;

FIG. 7 is a graph of the temperature change at three different locations of the cascaded copper sheets with different values of cooling water flow;

FIG. 8 is a graph of the temperature change at two different locations of the cascaded copper strip when the initial cooling water temperature is set at different values;

fig. 9 is a comparison of the cooling effect of two water-cooling structures and the existing water-cooling structure.

Detailed Description

The present invention will be described in detail with reference to specific examples.

The first embodiment is as follows:

according to the invention, as shown in fig. 1 to 9, a welding mode combining diffusion welding and silver welding is applied to the water-cooling structure design of the cascaded copper sheet, and the existing water-cooling structure is optimized, compared with the existing mode of punching holes on the side wall of the cascaded copper sheet and introducing cooling water, the optimized cooling effect of the cascaded copper sheet is improved.

The cascade copper sheet in the multichannel cascade electric arc source takes three channels as an example, the external structure of the cascade copper sheet is shown in figure 1, and the cascade copper sheet comprises a cylindrical copper sheet 1, molybdenum rings 2, 3 and 4 and a sealing ring 5, two stainless steel pipelines 6 and 7 are connected to the outside of the copper sheet and used as water inlet pipelines and water outlet pipelines, the diameter of the copper sheet is 60mm, the thickness of the copper sheet is 7mm, the inner diameter of each molybdenum ring is 2mm, the outer diameter of each molybdenum ring is 3mm, a hole with the diameter of 2mm in the middle of each molybdenum ring is a discharge channel of the multichannel cascade electric arc source, the circle center of each molybdenum ring is 10mm away from the circle center of the copper sheet, the three molybdenum rings are placed at an angle of 120 degrees, the diameter of each sealing ring is 40mm, the circle centers of the sealing ring are coincided with the circle centers of the copper sheets, and the sealing and insulating effects are achieved when a plurality of cascade copper sheets are stacked together. A water cooling channel is arranged in the copper sheet and is connected with two stainless steel pipelines 6 and 7 outside. An existing cascade copper sheet internal water cooling structure is shown in fig. 2, firstly, holes are punched on the outer wall of a copper sheet but the holes do not completely penetrate through the outer wall of the copper sheet to obtain two intersected water cooling channels 8 and 9, the diameters of the water cooling channels 8 and 9 are both 4mm, the intersection angle is 60 degrees, meanwhile, holes are punched below the two water cooling channels until the two water cooling channels intersect with the water cooling channel 9 to form a water cooling channel 10, the intersection angle between the water cooling channel 10 and the water cooling channels 8 and 9 is 60 degrees, and the diameter is 2 mm. The two stainless steel pipelines 6 and 7 and the copper sheet 1 are welded together at the positions of the water cooling channels 8 and 9 in a silver welding mode, the diameter of the position where the stainless steel pipelines 6 and 7 are connected with the copper sheet 1 is 4mm, the rest positions are 5mm, and the water cooling pipeline 10 and the pipeline 8 are welded in the area outside the copper sheet 1 by using a plug in the silver welding mode, so that the water cooling pipeline is watertight after cooling water is introduced. The method adopted by the invention comprises the steps of firstly manufacturing a cascaded copper sheet with the thickness of half 3.5mm, respectively digging grooves which are designed in advance and are used for introducing cooling water on the opposite sides of the two copper sheets, welding the two copper sheets with the thickness of 3.5mm together in a diffusion welding mode to obtain the copper sheet with the thickness of 7mm, connecting two stainless steel water-cooling pipelines with the grooves on the outer wall of the copper sheets by silver welding which is the same as the method, wherein the diffusion welding has the main principle that two workpieces to be welded are tightly pressed together and are placed in a vacuum or protective atmosphere furnace for heating, so that microscopic plastic deformation is generated on the micro-uneven parts of the two welding surfaces to achieve tight contact, and in the subsequent heating and heat preservation, atoms are mutually diffused to form metallurgical connection. Compared with the existing method, the cascade copper sheet obtained by adopting the diffusion welding method is not limited by the external structure of the copper sheet, and is convenient for designing a complex water path and improving the cooling efficiency.

Meanwhile, the invention carries out optimization design on the water-cooling structure of the existing three-channel cascade arc plasma source cascade copper sheet through finite element simulation according to the welding method provided by the invention. The method is used for modeling the cooling process of the coupling solid heat transfer and the non-isothermal pipeline flow to the copper sheet. The main principle is momentum and mass conservation equation, as shown in equations 1 and 2.

Wherein u is the average fluid velocity (m/s) of the cross section of the pipeline in the tangential direction of the central line of the pipeline, A is the cross section area (m2) of the pipeline, rho is the density (kg/m3), and p is the pressure (N/m 2). The second term on the right hand side of equation 1 represents pressure drop due to viscous shear, and fD is calculated using a Churchill friction model that is applicable to laminar flow, turbulent flow, and the transition region between the two, as shown in equations 3-6. Where fD is the friction factor, Re is the Reynolds number, e is the pipe roughness (μm), d is the pipe diameter (mm), and μ is the viscosity coefficient.

The heat transfer equation used is shown in equations 7-9, equation 7 is the energy equation for cooling water in the pipe, equation 8 is the energy equation for solid materials, i.e., copper sheets and molybdenum rings, and equation 9 is the heat exchange between the cooling water and the solid materials. Wherein Cp is constant-pressure heat capacity (J/(kg. K)), T is cooling water temperature (K), K is thermal conductivity (W/(m. K)), Qwall is a source term (W/m) of heat exchange between water and a copper sheet, and T2 is copper electrode temperature (K); z is the pipe circumference (m), h is the heat transfer coefficient (W/(m2 · K), Text is the pipe external temperature (K) the second term on the right in equation 7 represents the heat dissipation due to the internal friction of the fluid, which is negligible due to the shorter water cooling channel length.

Q_wall＝hZ(T_ext-T) (9)

Because the melting point of copper is 1357.77K, the specific heat capacity of three molybdenum rings on the copper sheet is large (250.78J/kg. K at 25 ℃) and the melting point is high (2893.15K), the copper sheet can be effectively protected in the discharging process, and the experimental data show that although the temperature of a plasma beam in a discharging channel can reach 104K magnitude, because the temperature on the copper sheet for protecting the molybdenum ring is not high, in the order of 102K, the melting point of copper is far lower, so the optimization of the cascade copper sheet water-cooling structure mainly focuses on the temperature of the copper sheet at the position where the sealing ring is placed on the surface and the temperature difference of each position of the sealing ring, because the working condition of the sealing ring is required to be below 130 ℃, the sealing ring is damaged or even broken due to long-time operation under high temperature, so that the multi-channel cascade arc plasma source cannot work due to the fact that the multi-channel cascade arc plasma source cannot reach the required vacuum environment, and meanwhile, the aging of the sealing ring can be accelerated due to the fact that the sealing ring has large temperature difference at each position. According to the actual cooling requirement of the cascaded copper sheet in the discharging process, two water cooling structures 1 and 2 are designed to optimize the existing cascaded copper sheet cooling channel, which are respectively shown in fig. 3 and 4. The water inlet pipeline and the water outlet pipeline in the figure 3 are arranged at 180 degrees, and in order to ensure that the cooling effect of the position of the sealing ring is the best, the cooling channel is superposed with the vertical position of the ring, and the diameters of the pipelines are all 4 mm. Fig. 4 adopts a common water cooling mode in a water cooling pipeline, cooling water flows through 5 semicircular curves after entering the cascaded copper sheets and then flows out, the diameter of each semicircular curve is 8.66mm, the diameter of a straight water cooling pipeline between two molybdenum rings is set to be 2mm in consideration of the size of the cascaded copper sheets, and the diameters of the rest water cooling pipelines are 4 mm.

In the embodiment, the cooling calculation of the cascade copper sheet water-cooling channel takes the existing three-channel cascade copper sheet water-cooling channel as an example. Fixing the temperature of the inner wall of the molybdenum ring, and carrying out simulation calculation on the temperature distribution of the cascade copper sheet after water is introduced. There are three methods for initial value setting of the cascade copper sheet and cooling water temperature, method 1: setting the initial temperature and the initial water temperature of the cascaded copper sheets to be the same as the temperature of the inner wall of the molybdenum ring, and setting the method 2: the initial temperature setting of the cascade copper sheet is the same as the inner wall of the molybdenum ring, the initial water temperature is set as the temperature set in the experiment, and the method 3: the initial temperature of the cascaded copper sheet is set to be room temperature (278.15K, the same as the experiment), the initial water temperature is set to be the temperature set in the experiment, the rest conditions are set to be the same (water flow is 10L/min), the temperature change curve of the point along with time obtained by the three methods is shown in figure 6 (taking the central point of the copper sheet as an example), the temperature of the point gradually reaches a steady state after 5s, the temperature values obtained by the three methods after the steady state are the same, and therefore the three methods are all applicable. However, in the method 1, the initial temperature setting is the same, the model is relatively stable compared with the methods 2 and 3, and the calculation speed is higher, so that the method 1 is adopted to calculate the cooling of the cascade copper sheet. Meanwhile, as can be seen from fig. 5, the temperature reaches a steady state after 5s, and in order to save calculation time, the simulation calculation time in the subsequent process is set to be 20 s.

FIG. 6 is a temperature change curve of three different positions of the cascade copper sheet when the temperature of the inner wall of the molybdenum ring is set to different values (300K-600K), and other parameters are fixed (water flow 4L/min, initial water temperature 15 ℃). FIG. 7 is a temperature change curve of three different positions of the cascaded copper sheet when the water flow is set to different values (0-20L/min), the other parameters are fixed (inner wall temperature 480K, initial water temperature 15 ℃). The temperature of each position on the cascade copper sheet is in a linear rising trend along with the rising of the temperature of the inner wall, and the temperature of the cascade copper sheet is reduced along with the increase of the flow of cooling water, but the falling rate is reduced.

FIG. 8 is a temperature change curve of two different positions of the cascade copper sheet with fixed other parameters (inner wall temperature 480K, water flow 4L/min) at different initial water temperatures (15-40 ℃). It can be seen that when the cooling water flow is low (less than 4L/min), the influence of the water inlet temperature on the temperature rise of the cascaded copper sheets is small, and when the cooling water flow is high, the temperature of the cascaded copper sheets is increased by increasing the initial water temperature, so that the cooling effect is poor.

In summary, for the comparison of the cooling effects of different water-cooling channel structures, the temperature of the inner wall of the molybdenum core, the flow rate of the cooling water and the initial water temperature parameter can be fixed, and the temperature change condition of each position of the lower-linked copper sheets of different water-cooling channel structures can be calculated.

The second embodiment is as follows: this embodiment will be described below with reference to fig. 3 to 5 and fig. 9. Because the structure of the cascade copper sheet is symmetrical, the water outlet/the water inlet are not divided into a plurality of parts in sequence. In fig. 2, the water cooling channel on the right side is used as a water inlet, and the water cooling channel on the left side is used as a water outlet. In fig. 3, the lower water-cooling channel serves as a water inlet and the upper water-cooling channel serves as a water outlet. In fig. 4, the right water-cooling channel serves as a water inlet, and the left water-cooling channel serves as a water outlet. In the simulation calculation, the temperature of the inner wall of the molybdenum core (570K), the flow rate of cooling water (4L/min, within the flow rate range of the cooling water in the experiment) and the initial water temperature (20 ℃) are fixed. And selecting a temperature point every 10 degrees around the sealing ring, and paying attention to the temperature distribution after the stable state under the water cooling structure. It can be seen that compared with the existing water cooling structure, the water cooling structure in fig. 3 and 4 has the overall temperature drop at the position of the sealing ring, and especially the cooling effect of the water cooling structure in fig. 5 is the best. Compared with the existing water cooling structure, the water cooling structure in fig. 3 has the advantages that the highest temperature of the position of the sealing ring is reduced by 6.1 ℃ (1.7%), the standard deviation of the temperatures of the position of the sealing ring is reduced to 4.64 from 7.67, the maximum temperature difference is reduced to 18.5 ℃ from 23.1 ℃, the temperature distribution of the position of the sealing ring is more uniform, and the ring aging caused by overlarge temperature difference of the positions is reduced. Compared with the existing water cooling structure, the water cooling structure in fig. 4 has the advantages that the highest temperature of the position of the sealing ring is reduced by 43.5 ℃ (11.9%), the standard deviation of the temperatures of the position of the sealing ring is reduced from 7.67 to 3.97, the maximum temperature difference is reduced from 23.1 ℃ to 14.8 ℃, meanwhile, the temperature difference between the outlet water and the inlet water (outlet water temperature-inlet water temperature) is increased from 7.56 ℃ to 14.18 ℃, and the cooling efficiency is improved by 87.6% under the same cooling water flow.

The above description is only a preferred embodiment of the operation method of the wireless locomotive signal code sending system, and the protection range of the operation method of the wireless locomotive signal code sending system is not limited to the above embodiments, and all technical solutions belonging to the idea belong to the protection range of the present invention. It should be noted that modifications and variations which do not depart from the gist of the invention will be those skilled in the art to which the invention pertains and which are intended to be within the scope of the invention.