Arc Plasma Flow Variation by Obstruction Structures between Anode and Cathode
Round 1
Reviewer 1 Report
Generally, the study is valuable and interesting. However, I think more system way can be used to analysis the given problem.
High-dimensional model representation-based global sensitivity analysis and the design of a novel thermal management system for lithium-ion batteries. Energy Conversion and Management, 190(JUN.), 54-72.
Sensitivity Analysis of Nonequilibrium Martian Entry Flow to Chemical and Thermal Modeling[J]. Journal of Thermophysics and Heat Transfer, 2017, 31(2):378-389.
Global sensitivity analysis for fiber reinforced composite fiber path based on d-morph-hdmr algorithm. Structural and Multidisciplinary Optimization, 1-16.
They used DOE and GSA to investigate the characteristic of objective function.
Moreover, COMSOL based model can be parameterized and can be easily constructed by python. I think it is not hard for the authors.
Finally, I think that the some parameters can be constructed parameterized and GSA should be applied to given problems.
Author Response
Point 1: Generally, the study is valuable and interesting. However, I think more system way can be used to analysis the given problem.
High-dimensional model representation-based global sensitivity analysis and the design of a novel thermal management system for lithium-ion batteries. Energy Conversion and Management, 190(JUN.), 54-72.
Sensitivity Analysis of Nonequilibrium Martian Entry Flow to Chemical and Thermal Modeling[J]. Journal of Thermophysics and Heat Transfer, 2017, 31(2):378-389.
Global sensitivity analysis for fiber reinforced composite fiber path based on d-morph-hdmr algorithm. Structural and Multidisciplinary Optimization, 1-16.
They used DOE and GSA to investigate the characteristic of objective function.
Moreover, COMSOL based model can be parameterized and can be easily constructed by python. I think it is not hard for the authors.
Finally, I think that the some parameters can be constructed parameterized and GSA should be applied to given problems.
Response 1: Thank you for your kind comments. The main topic of this paper is to simulate how the obstacle structure between two electrodes affects the arc plasma state. Therefore the variable is the shape of the structure of the obstacle between the electrodes and we suggest concave, sphere and cylinder shape as the variables. For example, the distance between the electrodes, the magnitude of the current, and the shape of the electrodes can also be variables, but they are not the subject of this paper, so we did not explain them in detail. I think the GSA and DOE suggested by the reviewer are useful methods when changing parameters for various variables and getting results accordingly. A more detailed analysis using GSA, such as concavities or the size of cylinders, will be dealt with in the future paper. Thank you again for providing references that will be of great help in preparing the next paper.
Additional edits:
[Author's affiliation]
Young Tae Cho1,*, Gwang Ho Jeong2, Chan Kyu Kim1, Won Pyo Kim1 and Young Cheol Jeong3
1 Department of Mechanical Engineering, Changwon National University, Changwon-si, Gyeongnam-do 51140, Republic of Korea;
2 Smart Manufacturing Engineering, Changwon National University, Changwon-si, Gyeongnam-do 51140, Republic of Korea;
3 Korea Textile Machinery Convergence Research Institute, Gyeongsan-si, Gyeongsangbuk-do 38542, Republic of Korea;
In addition, I uploaded the change file of the author's affiliation.
[page 5, line 17-30]
In Fig. 1, AJ is applied as an anode as ground. Since electrodes, nozzles, and anodes are not included in the simulation, it is assumed that a certain temperature is reached by applying a temperature boundary condition. The convergence property of simulation is low. In order to increase the convergence characteristics of the simulation, the mesh size near the electrode is more finely applied as shown in Fig. 2. Argon used as the shielding gas has unstable physical properties at high temperatures as shown in Fig. 3. Thus, the analysis of arc plasma is known to have very low convergence. Therefore, in order to increase the convergence of the analysis, the mesh was created differentially for the area where the arc plasma is generated, by using the mesh control function. The other boundaries are set as open boundaries and Argon shielding gas properties including thermal conductivity, density, dynamic viscosity, heat capacity, electrical conductivity and radiative emission coefficient are showed in Fig. 3. Because arc plasma is a complex multiphysics phenomenon, it considers electric fields, magnetic fields, fluid heat transfer, and fluid flow (laminar flow). It also considers multiphysics such as plasma heat source and temperature coupling in the computational domain. And in Fig. 3, the properties of argon gas are defined as a function of temperature and are required for plasma modules.
[Acknowledgements]
This work was supported by Korea Institute of Energy Technology Evaluation and Planning(KETEP) grant funded by the Korea government(MOTIE)( 20214000000480, Development of R&D engineers for combined cycle power plant technologies) and This result was supported by "Regional Innovation Strategy(RIS)" through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(MOE). and “This research was supported by the MSIT(Ministry of Science and ICT), Korea, under the Grand Information Technology Research Center support program(IITP-2021-2016-0-00318) supervised by the IITP(Institute for Information & communications Technology Planning & Evaluation).
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript describes the modelling of thermal plasma sources and compares the effect of different obstruction structures on the temperature profiles. The introduction and state of-the-art is clearly exposed. The method and underlying assumptions are clearly explained and the modelling results semi-quantitatively compared with literature values from experimental studies. Overall, this study is thus of high value for the field of plasma source design, both for academia and industry. I thus highly recommend publication of the manuscript.
There are some minors, that should be improved:
- check that all abbreviations are properly introduced in the text and that are not necessarily known by readers outside the field.
- The modules and versions of the COMSOL software used should be specified.
- Layout:
- improvement of some page breaks needed;
- font size to be adapted in the last paragraph of the conclusion
- spell or typo check
Author Response
Point 1: check that all abbreviations are properly introduced in the text and that are not necessarily known by readers outside the field.
Response 1: I appreciate your comments. The abbreviations currently used in the text are LTE, CFD, GMA, GTA, GTAW, and TIG. I very much agree with your opinion. Each abbreviation can be deciphered and written as follows in the paper.
(Manuscript modification)
[page 2, paragraph 2, line 4] LTE → Local Thermodynamic Equilibrium
[page 2, paragraph 2, line 10] CFD → Computational Fluid Dynamics(CFD)
[page 2, paragraph 2, line 17] GMA → Gas Metal Arc(GMA)
[page 3, paragraph 1, line 4] GTAW → Gas Tungsten Arc Welding(GTAW)
[page 3, paragraph 1, line 5] TIG → Tungsten Inert Gas(TIG)
Point 2: The modules and versions of the COMSOL software used should be specified.
Response 2: Yes, according to your comments, we specified the version and modules of COMSOL used for analysis simulation as follows.
(Manuscript modification)
[page 3, line 16-17]
COMSOL Multiphysics 5.4 versions with AC/DC, fluid flow, heat transfer, and plasma modules were used for the simulation and the analytical model is based on the following assumptions:
Point 3: improvement of some page breaks needed;
Response 3: Thank you very much for your detailed comments. I agree with your comments and the page breaks should be improved. Based on your comments, to improve page breaks, the figures and tables in the text have been relocated so that there are no blank spaces.
(Manuscript modification)
[page 6, 7, 8, 9, 10, 11, 12, 13 figure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
The overall figure and table of this paper have been rearranged.
Point 4: font size to be adapted in the last paragraph of the conclusion
Response 4: The font size to be applied to the last paragraph is unified to 10 points.
[page 13, paragraph 5]
When an obstruction structure such as a metal wire is disposed between the anode and the cathode, the temperature distribution of the arc plasma and the arc pressure on the base material is changed while interfering with the arc plasma flow. This phenomenon can be used to make the molten base material be influenced by the uniform arc pressure. The heat flux transferred to the base material is also changed by the obstruction structure, and it is shown that heat energy can be controlled appropriately.
Point 5: spell or typo check
Response 5: Thank you very much for your detailed comments. I also agree with you and there are many words that need to be corrected. I will be careful with spelling and typos. So I corrected spelling and typos from the first page to the last page.
(Manuscript modification)
[page 3, line 11, 27]
analyzing → to analyze, expressed → are expressed
[page 12, line 4, 5, 6]
is direction → is in the direction, showed → shown, more → is more
[page 12, Delete duplicate words from a caption in Figure 10]
The overlapping part of the shape of the velocity distribution of arc plasma according to obstruction structure in Figure 10 was deleted.
Fig. 10 Velocity distribution of arc plasma according to obstruction structure shape: (a) None type; (b) Sphere shape; (c) Cylinder shape; (d) Concave shape
[page 13, paragraph 5, line 4]
advance → advanced
Additional edits:
[Author's affiliation]
Young Tae Cho1,*, Gwang Ho Jeong2, Chan Kyu Kim1, Won Pyo Kim1 and Young Cheol Jeong3
1 Department of Mechanical Engineering, Changwon National University, Changwon-si, Gyeongnam-do 51140, Republic of Korea;
2 Smart Manufacturing Engineering, Changwon National University, Changwon-si, Gyeongnam-do 51140, Republic of Korea;
3 Korea Textile Machinery Convergence Research Institute, Gyeongsan-si, Gyeongsangbuk-do 38542, Republic of Korea;
In addition, I uploaded the change file of the author's affiliation.
[page 5, line 17-30]
In Fig. 1, AJ is applied as an anode as ground. Since electrodes, nozzles, and anodes are not included in the simulation, it is assumed that a certain temperature is reached by applying a temperature boundary condition. The convergence property of simulation is low. In order to increase the convergence characteristics of the simulation, the mesh size near the electrode is more finely applied as shown in Fig. 2. Argon used as the shielding gas has unstable physical properties at high temperatures as shown in Fig. 3. Thus, the analysis of arc plasma is known to have very low convergence. Therefore, in order to increase the convergence of the analysis, the mesh was created differentially for the area where the arc plasma is generated, by using the mesh control function. The other boundaries are set as open boundaries and Argon shielding gas properties including thermal conductivity, density, dynamic viscosity, heat capacity, electrical conductivity and radiative emission coefficient are showed in Fig. 3. Because arc plasma is a complex multiphysics phenomenon, it considers electric fields, magnetic fields, fluid heat transfer, and fluid flow (laminar flow). It also considers multiphysics such as plasma heat source and temperature coupling in the computational domain. And in Fig. 3, the properties of argon gas are defined as a function of temperature and are required for plasma modules.
[Acknowledgements]
This work was supported by Korea Institute of Energy Technology Evaluation and Planning(KETEP) grant funded by the Korea government(MOTIE)( 20214000000480, Development of R&D engineers for combined cycle power plant technologies) and This result was supported by "Regional Innovation Strategy(RIS)" through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(MOE). and “This research was supported by the MSIT(Ministry of Science and ICT), Korea, under the Grand Information Technology Research Center support program(IITP-2021-2016-0-00318) supervised by the IITP(Institute for Information & communications Technology Planning & Evaluation).
Author Response File: Author Response.pdf
Reviewer 3 Report
The manuscript is well designed and the results are clearly presented. Some issues are listed as follows:
1 Equation 14 is missing, please check?
2 The caption of Figure 3 is too simple, which should be rewritten.
3 In general, the discussion is rather poor in the results section, which should be improved.
4 Reference 24, 25 are not listed in the text, please check?
Author Response
Point 1: Equation 14 is missing, please check?
Response 1: Thank you very much for your detailed comments. I found equation 14 is missing so I have written equation number 14 instead of 15 and corrected all following equation numbers.
(Manuscript modification)
|
|
[page 5 line 2, page 8 table 1 changed]
(14)
Point 2: The caption of Figure 3 is too simple, which should be rewritten.
Response 2: I agree with your opinion. So I modified the caption of Figure 3. Each symbol is indicated in the caption of Figure 3 to indicate the physical properties of argon.
(Manuscript modification)
[page 7, The caption of Figure 3]
Fig. 3 (a): Density and thermal conductivity of argon gas, (b): Dynamic viscosity and Heat capacity at constant pressure of argon gas, (c): Electrical conductivity and Radiative emission coefficient of argon gas
Point 3: In general, the discussion is rather poor in the results section, which should be improved.
Response 3: I agree with that opinion. Therefore, let’s add some more content in the result part.
(Manuscript modification)
[page 10, paragraph 1, line 3-7 added]
In the vicinity of 1mm above the anode, the velocity of arc plasma is about 61m/s when the current is 100A, and the result value is 254m/s when the current is 150A. Comparing the results, the arc plasma velocity near the anode differed more than 4 times, and considering that the maximum velocity is 207m/s when the current is 100A, it can be seen that the current condition is a very important variable in the velocity of arc plasma.
(Manuscript modification)
[page 10, paragraph 2, line 8-11 added]
Fig. 7 shows the simulation results of arc pressure on the anode surface. The maximum arc pressure at the anode surface is about 780 Pa when the current is 150 A, which is more than 5 times that at 100 A. Additionally, the arc pressure on the surface of the cathode is about 1580 Pa when the current is 150A and about 580 Pa when the current is 100A, which is about 3 times different.
(Manuscript modification)
[page 11, paragraph 3, line 5-10 added]
Also, we compared temperature distribution using contour line of 10,000K for each type of obstacle structure. In the case of concave structure, the radius of the temperature contour line is about 7.0 mm on the anode surface as shown in Fig. 8(d). This radius is relatively shorter than that of other obstacle structures. In the case of an obstacle none type or a spherical obstacle, the radius of temperature contour line is about 9.3 mm as shown in Fig. 8(a) and (b), which means that the distribution of heat input to the anode surface is wider than that of concave obstacle.
Point 4: Reference 24, 25 are not listed in the text, please check?
Response 4: Thank you for your comments. I checked and I think there is no problem. Reference 24, 25 are not included in the text.
Additional edits:
[Author's affiliation]
Young Tae Cho1,*, Gwang Ho Jeong2, Chan Kyu Kim1, Won Pyo Kim1 and Young Cheol Jeong3
1 Department of Mechanical Engineering, Changwon National University, Changwon-si, Gyeongnam-do 51140, Republic of Korea;
2 Smart Manufacturing Engineering, Changwon National University, Changwon-si, Gyeongnam-do 51140, Republic of Korea;
3 Korea Textile Machinery Convergence Research Institute, Gyeongsan-si, Gyeongsangbuk-do 38542, Republic of Korea;
In addition, I uploaded the change file of the author's affiliation.
[page 5, line 17-30]
In Fig. 1, AJ is applied as an anode as ground. Since electrodes, nozzles, and anodes are not included in the simulation, it is assumed that a certain temperature is reached by applying a temperature boundary condition. The convergence property of simulation is low. In order to increase the convergence characteristics of the simulation, the mesh size near the electrode is more finely applied as shown in Fig. 2. Argon used as the shielding gas has unstable physical properties at high temperatures as shown in Fig. 3. Thus, the analysis of arc plasma is known to have very low convergence. Therefore, in order to increase the convergence of the analysis, the mesh was created differentially for the area where the arc plasma is generated, by using the mesh control function. The other boundaries are set as open boundaries and Argon shielding gas properties including thermal conductivity, density, dynamic viscosity, heat capacity, electrical conductivity and radiative emission coefficient are showed in Fig. 3. Because arc plasma is a complex multiphysics phenomenon, it considers electric fields, magnetic fields, fluid heat transfer, and fluid flow (laminar flow). It also considers multiphysics such as plasma heat source and temperature coupling in the computational domain. And in Fig. 3, the properties of argon gas are defined as a function of temperature and are required for plasma modules.
[Acknowledgements]
This work was supported by Korea Institute of Energy Technology Evaluation and Planning(KETEP) grant funded by the Korea government(MOTIE)( 20214000000480, Development of R&D engineers for combined cycle power plant technologies) and This result was supported by "Regional Innovation Strategy(RIS)" through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(MOE). and “This research was supported by the MSIT(Ministry of Science and ICT), Korea, under the Grand Information Technology Research Center support program(IITP-2021-2016-0-00318) supervised by the IITP(Institute for Information & communications Technology Planning & Evaluation).
Author Response File: Author Response.pdf
