Numerical Investigation on EOR in Porous Media by Cyclic Water Injection with Vibration Frequency
Round 1
Reviewer 1 Report
The manuscript did the numerical investigation on EOR in porous media by cyclic water injection with vibration frequency. There are some problems in the manuscript the authors should be carefully addressed as follows.
(1) There are many grammar mistakes in the manuscript and it should be thoroughly checked and modified.
(2) Please introduce your investigations in the third person perspective, not the first person “we”. It could be modified by the passive voice in the whole manuscript.
(3) “The numerical investigation” is the main work in your manuscript, then the numerical results should be enough provided in the Abstract part and the Conclusion part.
(4) The orders of the subtitles of “4. Results and discussion” are all incorrect.
(5) The titles and subtitles of “2. Methodology” and “3. Benchmark” should be rewritten to specify your investigation.
(6) The highlights should be clearly presented in the Conclusion part.
Author Response
Dear reviewer,
We appreciate the comments and kind suggestions. Below is the point-by-point responses and the attached is the revised manuscript.
(1) There are many grammar mistakes in the manuscript and it should be thoroughly checked and modified.
Responses:
Thanks for your comments. We have checked the manuscript carefully and revised the grammar mistakes.
(2) Please introduce your investigations in the third person perspective, not the first person “we”. It could be modified by the passive voice in the whole manuscript.
Responses:
Thanks for your comments. We have revised the manuscript to report our work in a third person perspective. The passive is used as well.
(3) “The numerical investigation” is the main work in your manuscript, then the numerical results should be enough provided in the Abstract part and the Conclusion part.
Responses:
Thanks for your comments. We have enhanced our numerical results and discoveries in the Abstract and Conclusion sections.
(4) The orders of the subtitles of “4. Results and discussion” are all incorrect.
Responses:
Thanks for your comments. We have revised the subtitle order carefully.
(5) The titles and subtitles of “2. Methodology” and “3. Benchmark” should be rewritten to specify your investigation.
Responses:
Thanks for your comments. We have revised the subtitles of section 2 and 3 to specify the logic of our work.
(6) The highlights should be clearly presented in the Conclusion part.
Responses:
Thanks for your comments. We have highlighted the discoveries in this work in the Conclusion section, specifically:
- An optimal EOR of roughly 10% is achieved at the critical water injection frequency compared with water injection without an oscillatory boundary.
- The required critical frequency increases with higher surface tension and larger oil viscosity is revealed.
- At a constant injection frequency, a higher EOR is achieved as the water-oil surface tension is lower but the oil viscosity is larger.
Best regards,
Hongqing Song
Author Response File: 
Author Response.docx
Reviewer 2 Report
Overall, the work load of this manuscript is not sufficient, and the language should be significantly improved.
Abstract：
The language of the first sentence could be improved. “…but whose oil recovery performance 10 is unstable and far from optimal due to the critical injection frequency is unclarified.”
The abstract section should clarify the facts/results that were revealed through the established model. I would suggest the authors to avoid using “we” in the abstract section.
Introduction
The last paragraph in the introduction should present the objective of the study, the organization of the following sections, etc.
Author Response
Dear reviewer,
We appreciate your comments and kind suggestions. Below is the point-by-point response to your comments and attached is the revised manuscript.
(1) Overall, the work load of this manuscript is not sufficient, and the language should be significantly improved.
Responses:
Thanks for your comments. We have enhanced every section and carefully revised the language of the manuscript.
(2) Abstract: The language of the first sentence could be improved. “…but whose oil recovery performance is unstable and far from optimal due to the critical injection frequency is unclarified.”
Responses:
Thanks for your comments. We have revised the language in the Abstract section carefully.
(3) The abstract section should clarify the facts/results that were revealed through the established model. I would suggest the authors to avoid using “we” in the abstract section.
Responses:
Thanks for your comments. We have enhanced the results and discoveries revealed from our numerical model in the Abstract section. The passive is also used in the Abstract instead of using “We”.
(4) Introduction: The last paragraph in the introduction should present the objective of the study, the organization of the following sections, etc.
Responses:
Thanks for your comments. We have revised the last paragraph of the Introduction according to your comments.
Best regards,
Hongqing Song
Author Response File: Author Response.docx
Reviewer 3 Report
1. The novelty of this work needs to be included in the introduction section. Write what is new in this work to highlight your contribution in this field of research.
2. All the equations are not cited within text. Can you please check this out and take measures to include all.
3. Should benchmark be a seperate section or be included in the methodology section. please check.
4. The discussion is non existent in this paper. None of the results are explained or why such observations were made discussed in the text. Plese improve this aspect significantly. Also include references in the discussion to compare your results with previously obtained ones. By this the significance of your work could be highlighted.
5. Conclusion is quite limited. Could you only find a single significant conclusion from this study. Most of the first paragraph is just what you did, which should not be included in conclusion rather only the salient findings from the study. Please check and make significant improvement.
Author Response
Dear reviewer,
We appreciate your comments and kind suggestions. Below is the point-by-point response to your comments and attached is the revised manuscript.
(1) The novelty of this work needs to be included in the introduction section. Write what is new in this work to highlight your contribution in this field of research.
Responses:
Thanks for your comments. We have enhanced the novelty and the significance of our work in the Introduction section.
(2) All the equations are not cited within text. Can you please check this out and take measures to include all.
Responses:
Thanks for your comments. We have carefully revised the manuscript and cited all the equations in the text.
(3) Should benchmark be a seperate section or be included in the methodology section. please check.
Responses:
Thanks for your comments. We decide to keep the Benchmark section separate after discussion to maintain the logic and continuity of our work.
(4) The discussion is non existent in this paper. None of the results are explained or why such observations were made discussed in the text. Plese improve this aspect significantly. Also include references in the discussion to compare your results with previously obtained ones. By this the significance of your work could be highlighted.
Responses:
Thanks for your comments. We have enhanced the discussions and interpred our discoveries carefully. We have compared our numerical results with the literature in section 4.1 according to your comments.
(5) Conclusion is quite limited. Could you only find a single significant conclusion from this study. Most of the first paragraph is just what you did, which should not be included in conclusion rather only the salient findings from the study. Please check and make significant improvement.
Responses:
Thanks for your comments. We have enhanced the conclusions of our work by highlighting the results and discoveries revealed from our numerical model and simulations.
Best regards,
Hongqing Song
Author Response File: Author Response.docx
Reviewer 4 Report
Comments for author File: 
Comments.pdf
Author Response
Dear reviewer,
We appreciate your comments and kind suggestions. Below is the point-by-point response to your comments and attached is the revised manuscript.
(1) The discussion about the numerical methods should be enhanced, including spectral methods. See for example textbooks like
Lloyd N. Trefethen, Spectral Methods in MATLAB, SIAM, Philadelphia, 2000
Spectral Methods in Fluid Dynamics, Claudio Canuto, M.Yousuff Hussaini, Alfio
Quarteroni, Thomas A., Jr. Zang
and some of their applications:
Direct Numerical Simulation of a Turbulent Flow Using a Spectral/hp Element Method by Andrei Shishkin and Glaus Wagner
Some nonlinear equation solvers:
https://doi.org/10.1007/BF01669671
https://www.sciencedirect.com/science/article/pii/S2211379719309301
https://www.sciencedirect.com/science/article/pii/002199918790091X
https://www.sciencedirect.com/science/article/pii/S2666818121000231
Also a general discussion on finite elements and finite volume methods would be useful. Please elaborate the discussion including these references using a paragraph.
Responses:
Thanks for your comments. The discussion about the numerical methods and the finite volume methods (FVM) has be enhanced in our work. It is our pleasure about your advice in numerical methods of spectral methods, but this is not very relevant to our research direction.
(2) Please give the analytical result by Deng and discuss it.
Responses:
Thanks for your comments. We have given the analytical result in Figure 3 represented as black line and numbers. And we enhanced the discussion of the result by Deng et al. in Model benchmark.
(3) For the problem depicted in Fig 2, there are some solutions of the contracted pipe flows, also many analyses involving roughness and Moody’s chart. See for example Munson, Young, Okiishi, Huebsch, Fundamentals of Fluid Mechanics.
Giving the pressure difference before and after the pipe contraction, comparing it with those of the Hagen-Poiseuille flow may be useful.
Responses:
Thanks for your comments. The effect of roughness on flow is not discussed in our study. The scale of our study is different from that of the Hagen Poiseuille flow, so it may be meaningless to verify this study with the Hagen Poiseuille flow.
(4) Also, I would like to learn opinions of authors when not a single frequency but a multi frequency cyclic water pumping is used. Any comments and additions would be appreciated.
Responses:
Thanks for your comments. Indeed, changing the frequency during water injection is also a problem worth studying. Using different frequencies in different stages such as before and after water breakthrough may further enhanced oil recovery. We will discussion this worth problem in future.
Best regards,
Hongqing Song
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
(1) The numerical results have not yet been enough provided in the Abstract part and the Conclusion part.
(2) The past tense is recommended for the expression of the investigation for yours and other studies in the whole manuscript.
Author Response
Dear reviewer,
We appreciate your comments and kind suggestions. Below is the point-by-point response to your comments and attached is the revised manuscript.
（1）The numerical results have not yet been enough provided in the Abstract part and the Conclusion part.
Responses:
Thanks for your comments. We have enhanced the numerical results in Abstract and Conclusion.
（2）The past tense is recommended for the expression of the investigation for yours and other studies in the whole manuscript.
Responses:
Thanks for your comments. We have changed the expression of the investigation for our and other studies to the past tense.
Author Response File: Author Response.docx
Reviewer 3 Report
It can be accepted in the current form
Author Response
Thank you!
Author Response File: Author Response.docx
