Computational Fluid Dynamics Simulation of Combustion Efficiency for Full-Size Upstream Flare Experiments
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsExperimental and simulation study which can be useful for practical activities.
Author Response
Thank you.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe article provides a nice literature review on the topic of flare and CFD appraoch for modeling it. However, as a research article mainly by simulation appraoch, it lacks necessary validation of the model applied. Below is a list of comments and suggestions.
1. No figure for Flame D simulation was given, and the modeling setup is also unclear, which is unacceptable for validation purpose.
2. Please provide information for flare tip size and the cell size (minimum to maximum).
3. The mesh-independency and domain-independecy should be checked.
4. It states that a numerical parametric model was developed, but no details about the model was given, i.e. formula. This is also unacceptalbe as a research article.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThis report is well-written, but it lacks a novel idea expected in articles.
It would have been better that authors included their numerical results along with their experimental results they recently published.
Therefore, I would not recommend publishing this manuscript.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
Comments and Suggestions for AuthorsIn their response letter, the authors demonstrated how their study contribute to the field. However, their introduction fails to clearly highlight the novelty and strengths of their work. Therefore, the introduction should be carefully revised to comprehensively describe the unique aspects and strengths of the study, rather than being confined to a brief paragraph. Plus, comparing the results with lab-scale reference data does not show a significant novelty in this case, as I will explain later. So, this should not be presented as a strength of the study.
My comments are as follows:
1- During this revision, I found several typos and grammar errors. Please carefully review the text.
2- Please check if subscripts and superscript are written correctly.
3- The abstract is currently very poor and reads more like an introduction. Please remove the extra explanations in the first few lines, as these should be addressed in the introduction. Focus more on what you did in the study. Include one or two sentences bout your numerical modeling, specifically mentioning the use of the FGM model. Additionally, avoid qualitative explanations of the results. Instead, add more quantitative results with specific numbers.
4- In the simulation methodology section, the authors only mentioned that the transport equations are based on ANSYS software. This is insufficient for an article that numerically addresses an issue. Please include the general transport equations used in this article for numerical simulations.
5- Please clarify which radiation model has been used for the simulation.
6- For the radiative properties of gases, which models have been used? All these parameters significantly influence the final results, but the authors did not describe any of them.
7- Add more details about FGM and include the related equations and assumptions to help reader better understand your numerical approach.
8- Figure 1 and Figure 2 show different types of mesh; tetrahedral vs polyhexacore. Why?
9- “Investigation of crosswind”; 10-4 to 103? Did you mean 10-4?
10- N2 in tables should be N2
11- Why did the authors exactly verify Sandia Flame D? What did they find through this validation? Their simulation results deviated from experimental data. Despite these discrepancies, they concluded their results were sufficiently accurate. They claimed that they could tune parameters by comparing simulation results with Flame D. As the deviations persisted, the question raised that why they did not modify their approach by considering more advanced turbulence models like LES, or turbulence-chemistry models, instead of FGM, for improved accuracy. Moreover, they used default ANSYS Fluent equations plus FGM, to model Flame D which have been performed by several authors previously. What did this section really contribute to the field?
They mentioned this part of simulation (lab-scale simulation before the flaring simulation) as a novelty, but I do not think it is a novelty! Prior to their simulation, available research had already demonstrated results of Flame D.
All in all, I strongly recommend removing this section and do not pointing it as a strength of this research work.
12- The quality of text in the figures and the size of legends is substandard, particularly in figures 5 and 7.
13- On line 361-369, what is your assessment of the impact of the FGM model on the results? Considering there are more accurate turbulence-chemistry models available, it would be beneficial to mention that some errors might be originated from applying this model.
14- On line 364, model outputs are not similar. So please modify it.
15- Lines 378-388, please provide a discussion on Table 4.
16- Please do not include additional explanations in the conclusion. Remove lines 499-503, as this explanation is not suitable for the conclusion section.
17- Please provide future outlook.
Comments on the Quality of English Languageshould be improved
Author Response
Please see the attached.
Author Response File: 
Author Response.docx
