Heat-Flow Coupling Law for Freezing a Pipe Reinforcement with Varying Curvatures

Round 1

Reviewer 1 Report

Dear Editor Journal of applied science  

The article entitled “Research on the heat flow coupling law of freezing reinforce-2 ment of freezing pipes with different curvatures”, have useful scientific information. But, paper in present format require to minor revisions. Specific remarks are as follow:  

1- Important results should be expressed quantitatively in abstract.

2- In terms of grammar, paper should be re written again.

3- In COMSOL analysis, interaction between soil-pipe was considered? It should be described in text.

4- In numerical analysis, which constitutive model was considered for soil and pipe material? It should be described in text.

5- For table 3, reference should be proposed in text.

6- Quality of figures should be better in text.

Best regards

In terms of grammar, paper should be re written again

Author Response

Responses to Reviewers' comments:

First of all, the authors would like to thank the reviewer for their encouraging feedback and constructive comments on this manuscript. In the following sections, comments will be addressed or clarified point-by-point. Necessary changes made to the manuscript and figures are highlighted in yellow as well.

Reviewer's comments and authors’ responses

Comment 1:  

Important results should be expressed quantitatively in abstract.

Responses:

Some quantitative results have been added to the abstract of this paper, see the yellow-lettered portions of 18-27 in the abstract.

Comment 2:  

In terms of grammar, paper should be re written again.

Responses:

The entire text has been grammatically corrected by a member of the Better English team.

Comment 3:  

In COMSOL analysis, interaction between soil-pipe was considered? It should be described in text.

Responses:

In the COMSOL analysis in this paper, the interaction between the soil and the pipe is not considered, and the formation chamber of the pipe is subtracted by the Borel operation of the model, and the temperature load is added to the subtracted pipe surface. Added in text 166-167, 194-196 yellow font changes.

Comment 4:  

In numerical analysis, which constitutive model was considered for soil and pipe material? It should be described in text.

Responses:

In the numerical analysis, the deformation of the soil pipe is ignored, Intrinsic modeling is not addressed in the text and the changes of the model temperature field and seepage field are mainly studied. In the material setting module, different parameters are set to differentiate the materials, and the main research parameters include: thermal conductivity, constant pressure heat capacity and other thermophysical parameters. In the text 175-176 has been added in yellow font

Comment 5:  

For table 3, reference should be proposed in text.

Responses:

In order to simulate the most unfavorable scenario, the most unfavorable soils having similar sand layer properties were selected as the soil materials, which have been highlighted in yellow font in the text 204-208, and references are given below:

Wu, Y.; Zeng, H.; Hu, J.; Ren, X.; Xue, X. Finite Element Study on Temperature Field of Underwater Dredging Devices via the Artificial Ground Freezing Method. Geofluids. 2022, 7502693.

Comment 6:  

Quality of figures should be better in text.

Responses:

The authors have modified some of the figures, e.g., Fig. 1, Fig. 9.

Author Response File: Author Response.docx

Reviewer 2 Report

Manuscript ID: applsci-2580307

Title: Research on the heat flow coupling law of freezing reinforcement of freezing pipes with different curvatures

Applied Sciences

The paper presents an interesting subject related to freezing pipes. The following notes were outlined:

1.     Details about the numerical model should be added  to the “Abstract”.

2.     Page 3: “Coupling of the 112 seepage field to the temperature field “, what are the state variables of coupling ?

3.     Page 4 – line 163: “The temperature load is directly applied to the wall of the freezing pipe”, why ? what about the pipe inner side ?

4.     Page 5 – line 167: “a uniform temperature field”, do you mean along the entire soil ?

5.     Are the parameters in Table 3 assumed ?

6.     Page 7 – line 256: “the isothermal change 256 before and after seepage is small, which also confirms that seepage has a larger impact on 257 the upstream”, how ?

7.     In Fig. 4, illustrate the point or surface from which the distance is measured.

8.     The “Conclusions” must be supported by some numerical values or percentages.

9.     The following studies may be beneficial. You can also refer to them:

·        Fattah, M. Y., Salman, F. A., and Hassan, A. R., (2004). “Tracing the Path of Flow of Particles in Porous Media”, Engineering and Technology Journal, University of Technology, Vol. 23, No.2, pp. 39-50.

·        Al–Damluji, O. F., Fattah, M. Y., and Adthami, R. A. J., (2004). “Solution of Two-Dimensional Steady-State Flow Field Problems by the Boundary Element Method”, Engineering and Technology Journal, University of Technology, Vol. 23, No. 12, p.p. 750 – 766.

Author Response

Responses to Reviewers' comments:

First of all, the authors would like to thank the reviewer for their encouraging feedback and constructive comments on this manuscript. In the following sections, comments will be addressed or clarified point-by-point. Necessary changes made to the manuscript and figures are highlighted in yellow as well.

Reviewer's comments and authors’ responses

Comment 1:  

Details about the numerical model should be added to the “Abstract”.

Responses:

A modeling section description has been added to the text 12-16.

Comment 2:  

Page 3: “Coupling of the 112 seepage field to the temperature field “, what are the state variables of coupling?

Responses:

The coupled state variable in the paper is temperature, the temperature field model satisfies the principle of heat transfer in porous media, and the seepage field satisfies Darcy's law. From the assumption of uniform saturated soil, the surface temperature of the freezing tube decreases, freezing the surrounding water-containing soil undergoes a phase change reaction and the process of icing.

Comment 3:  

Page 4 – line 163: “The temperature load is directly applied to the wall of the freezing pipe”, why? what about the pipe inner side ?

Responses:

According to the assumption of previous scholars' research, the temperature load can be acted on the outer wall of freezing, the freezing tube refrigeration through the refrigerant is a complex process, and the actual engineering of the freezing tube transmission of cold is not uniform and there is a certain degree of error, therefore, the temperature load is directly acted on the outer wall of the freezing tube is essentially to do a simplified processing.

Comment 4:  

Page 5 – line 167: “a uniform temperature field”, do you mean along the entire soil?

Responses:

The uniform temperature field referred to here is a simplifying assumption made for the entire soil body. It is assumed that the temperature is equal at each place in the soil body when it has not yet been frozen and consolidated, and the initial ground temperature in the text is 27.5℃.

Comment 5:  

Are the parameters in Table 3 assumed?

Responses:

Table 3 parameters in the paper combined with the research of related scholars, in order to simulate the most unfavorable situation, the most unfavorable has similar sand layer properties of the soil as the soil material is selected. The related scholars' studies are as follows:

Wu, Y.; Zeng, H.; Hu, J.; Ren, X.; Xue, X. Finite Element Study on Temperature Field of Underwater Dredging Devices via the Artificial Ground Freezing Method. Geofluids. 2022, 7502693.

Comment 6:  

Page 7 – line 256: “the isothermal change 256 before and after seepage is small, which also confirms that seepage has a larger impact on 257 the upstream”, how?

Responses:

Along the two sides of the main surface of the freezing tube is divided into upstream and downstream, the thickness of the freezing wall on the upstream side varies greatly under the action of hydrostatic and dynamic water, while the downstream varies less, indicating that seepage has a greater influence on the upstream.

Comment 7:  

In Fig. 4, illustrate the point or surface from which the distance is measured.

Responses:

A schematic of the location of the observation surface has been added to FIG. 4.

Comment 8:  

The “Conclusions” must be supported by some numerical values or percentages.

Responses:

Some numerical results have been added to the conclusions, see the yellow-faced portion of the text at 523-535.

Comment 9:  

The following studies may be beneficial. You can also refer to them:

• Fattah, M. Y., Salman, F. A., and Hassan, A. R., (2004). “Tracing the Path of Flow of Particles in Porous Media”, Engineering and Technology Journal, University of Technology, Vol. 23, No.2, pp. 39-50.
• Al–Damluji, O. F., Fattah, M. Y., and Adthami, R. A. J., (2004). “Solution of Two-Dimensional Steady-State Flow Field Problems by the Boundary Element Method”, Engineering and Technology Journal, University of Technology, Vol. 23, No. 12, p.p. 750 – 766.

Responses:

Reading these studies has been quite pu inspiring for the authors and have used them as references.

Author Response File: Author Response.docx

Reviewer 3 Report

REVIEWER’S COMMENTS (applsci-2580307)

The manuscript analyzes the development law and characteristics of the temperature field and seepage field of the single tube and multiple tubes frozen at different arcs.  The manuscript needs a major revision for it to be accepted for publication. My comments are as follows:

1. Lines 2-3: The title of the article should not contain redundant phrases such as “Research on”. The authors need to rephrase the title of the article by removing the redundant phrase.

2. Lines 12-27: The abstract was poorly written. The grammatical errors and incorrect use of punctuation marks distorted the content of the abstract. All the sentences are too complex and difficult to understand. The abstract should not be started with a preposition such as “To”. The authors need to restructure the complex sentences to make them meaningful. The authors should ensure the correct use of punctuation marks. I recommend a total rewrite of the abstract.

3. Line 84: Change '0. Introduction' to '1. Introduction'

4. Line 31: Change '1. Arc Freeze Tube Design' to '2. Arc Freeze Tube Design'

5. Line 108: Change '2. Modeling Arc Freeze Tubes' to '3. Modeling Arc Freeze Tubes'

6. Line 109: Change '2.1. Heoretical model of freezing' to '3.1. Theoretical model of freezing'

7. Line 155: Change '2.2. Basic assumptions' to '3.2. Basic assumptions'

8. Line 210: Change '3. Analysis of the calculation results of the single-pipe model' to '4. Analysis of the calculation results of the single-pipe model'

9. Line 211: Change '3.1. Temperature field cloud map analysis' to '4.1. Temperature field cloud map analysis'

10. Line 243: Change '3.2. Freezing wall analysis' to '4.2. Freezing wall analysis'

11. Line 292: Change '3.3. Analysis of the seepage field' to '4.3. Analysis of the seepage field'

12. Line 349: Change '4. Multi-pipe modeling and analysis of calculation results' to '5. Multi-pipe modeling and analysis of calculation results'

13. Line 350: Change '4.1. Multi-pipe numerical modeling' to '5.1. Multi-pipe numerical modeling'

14. Line 365: Change '4.2. Analysis of the results of multi-pipe freezing calculations' to '5.2. Analysis of the results of multi-pipe freezing calculations'

15. Line 418: Change '5. Application of working conditions' to '6. Application of working conditions'

16. Line 419: Change '5.1. Background and modeling of working conditions' to '6.1. Background and modeling of working conditions'

17. Line 442: Change '5.2. Calculation results and analysis' to '6.2. Calculation results and analysis'

18. Line 506: Change '6. Conclusions' to '7. Conclusions'

19.  The sentences in the manuscript are poorly structured and this makes it difficult for readers to understand them. The authors need to work on improving the readability of the article.

20. Lines 498-505: There are too many complex sentences with distorted meanings. An example is this sentence below:

“Long arc ratio s = 7 arc pipe frozen soil curtain thickness is thicker than the straight pipe, the final frozen 58d days thicker than the straight pipe is close to 400mm; which arc pipe frozen about 46d thickness is approximately equal to the straight pipe frozen 58d thickness, in other conditions remain unchanged, saving 12d freezing time, greatly shortening the construction time limit; and the water curtain is arch-shaped, better form of force, proving the arc pipe in the surge water This proves that the arc pipe has certain superiority in the effect of water insulation in water gushing stratum.”

The authors made the article very uninteresting by using this kind of unclear sentence throughout the manuscript. So, it is difficult for me as a reviewer to understand the findings of the study.

21. The authors should make Fig 12b more eligible and clearer.

22. Lines 212-213: Change “Calculated results Fig. 3 shows the temperature field and seepage field cloud diagrams of the straight pipe and the curved pipe with different s-values after freezing for 58 days under hydrostatic and moving water conditions” to “Fig. 3 shows the temperature field and seepage field cloud diagrams of the straight pipe and the curved pipe with different s-values after freezing for 58 days under hydrostatic and moving water conditions”

The quality of the English Language in this article is poor. The authors need to work on improving the readability of the article.

Author Response

Responses to Reviewers' comments:

First of all, the authors would like to thank the reviewer for their encouraging feedback and constructive comments on this manuscript. In the following sections, comments will be addressed or clarified point-by-point. Necessary changes made to the manuscript and figures are highlighted in yellow as well.

Reviewer's comments and authors’ responses

Comment 1:  

Lines 2-3: The title of the article should not contain redundant phrases such as “Research on”. The authors need to rephrase the title of the article by removing the redundant phrase.

Responses:

Changes have been made to the title.

Comment 2:  

Lines 12-27: The abstract was poorly written. The grammatical errors and incorrect use of punctuation marks distorted the content of the abstract. All the sentences are too complex and difficult to understand. The abstract should not be started with a preposition such as “To”. The authors need to restructure the complex sentences to make them meaningful. The authors should ensure the correct use of punctuation marks. I recommend a total rewrite of the abstract.

Responses:

Appropriate changes have been made to the summary section.

Comment 3:  

Line 84: Change '0. Introduction' to '1. Introduction'

Responses:

Changes have been made to the appropriate locations.

Comment 4:  

Line 31: Change '1. Arc Freeze Tube Design' to '2. Arc Freeze Tube Design'

Responses:

Changes have been made to the appropriate locations.

Comment 5:  

Line 108: Change '2. Modeling Arc Freeze Tubes' to '3. Modeling Arc Freeze Tubes'

Responses:

Changes have been made to the appropriate locations.

Comment 6:  

Line 109: Change '2.1. Heoretical model of freezing' to '3.1. Theoretical model of freezing'

Responses:

Changes have been made to the appropriate locations.

Comment 7:  

Line 155: Change '2.2. Basic assumptions' to '3.2. Basic assumptions'

Responses:

Changes have been made to the appropriate locations.

Comment 8:  

Line 210: Change '3. Analysis of the calculation results of the single-pipe model' to '4. Analysis of the calculation results of the single-pipe model'

Responses:

Changes have been made to the appropriate locations.

Comment 9:  

Line 211: Change '3.1. Temperature field cloud map analysis' to '4.1. Temperature field cloud map analysis'

Responses:

Changes have been made to the appropriate locations.

Comment 10:  

Line 243: Change '3.2. Freezing wall analysis' to '4.2. Freezing wall analysis'

Responses:

Changes have been made to the appropriate locations.

Comment 11:  

Line 292: Change '3.3. Analysis of the seepage field' to '4.3. Analysis of the seepage field'

Responses:

Changes have been made to the appropriate locations.

Comment 12:  

Line 349: Change '4. Multi-pipe modeling and analysis of calculation results' to '5. Multi-pipe modeling and analysis of calculation results'

Responses:

Changes have been made to the appropriate locations.

Comment 13:  

Line 350: Change '4.1. Multi-pipe numerical modeling' to '5.1. Multi-pipe numerical modeling'

Responses:

Changes have been made to the appropriate locations.

Comment 14:  

Line 365: Change '4.2. Analysis of the results of multi-pipe freezing calculations' to '5.2. Analysis of the results of multi-pipe freezing calculations'

Responses:

Changes have been made to the appropriate locations.

Comment 15:  

Line 418: Change '5. Application of working conditions' to '6. Application of working conditions'

Responses:

Changes have been made to the appropriate locations.

Comment 16:  

Line 419: Change '5.1. Background and modeling of working conditions' to '6.1. Background and modeling of working conditions'

Responses:

Changes have been made to the appropriate locations.

Comment 17:  

Line 442: Change '5.2. Calculation results and analysis' to '6.2. Calculation results and analysis'

Responses:

Changes have been made to the appropriate locations.

Comment 18:  

Line 506: Change '6. Conclusions' to '7. Conclusions'

Responses:

Changes have been made to the appropriate locations.

Comment 19:  

The sentences in the manuscript are poorly structured and this makes it difficult for readers to understand them. The authors need to work on improving the readability of the article.

Responses:

The entire text was revised by the better English-speaking team members.

Comment 20:  

Lines 498-505: There are too many complex sentences with distorted meanings. An example is this sentence below:

“Long arc ratio s = 7 arc pipe frozen soil curtain thickness is thicker than the straight pipe, the final frozen 58d days thicker than the straight pipe is close to 400mm; which arc pipe frozen about 46d thickness is approximately equal to the straight pipe frozen 58d thickness, in other conditions remain unchanged, saving 12d freezing time, greatly shortening the construction time limit; and the water curtain is arch-shaped, better form of force, proving the arc pipe in the surge water This proves that the arc pipe has certain superiority in the effect of water insulation in water gushing stratum.”

Responses:

Changes have been made to the appropriate locations.See text at 506-511.

Comment 21:  

The authors should make Fig 12b more eligible and clearer.

Responses:

Changes have been made to Figure 12b.

Comment 22:  

Lines 212-213: Change “Calculated results Fig. 3 shows the temperature field and seepage field cloud diagrams of the straight pipe and the curved pipe with different s-values after freezing for 58 days under hydrostatic and moving water conditions” to “Fig. 3 shows the temperature field and seepage field cloud diagrams of the straight pipe and the curved pipe with different s-values after freezing for 58 days under hydrostatic and moving water conditions”

Responses:

Changes have been made to the appropriate locations.

Author Response File: Author Response.docx

Reviewer 4 Report

The provided research paper describes a study that investigates the freezing law and development trend of curved freezing pipes in the ground using numerical simulations and COMSOL Multiphysics software. Here are some critical comments and considerations regarding this research:

1. The research paper lacks context regarding the specific application and significance of the study. It mentions the freezing of pipes in the ground but doesn't explain why this is important or what practical implications it has. Providing some background information or real-world examples would make the research more accessible.

2. The research paper briefly mentions the use of COMSOL Multiphysics software to establish numerical models, but it doesn't provide any details about the methodology, boundary conditions, or assumptions made during the simulations. A more thorough explanation of the research methodology would be essential for understanding the study.

3. While the research paper mentions some results, such as the differences in frozen wall thickness between curved and straight pipes, it lacks a detailed explanation of these findings. Readers would benefit from a discussion of the implications of these results and how they relate to the overall research objectives.

4. The research paper uses technical terms like "long arc ratio s" and "permafrost curtain thickness" without providing clear definitions or explanations. It's important to make sure that such technical terms are defined or explained for readers who may not be familiar with the specific terminology.

5. Visual representations of the simulation results, such as graphs or diagrams, would greatly enhance the reader's understanding of the findings. Without visuals, it can be challenging to interpret and appreciate the results.

6. It's not clear from the research paper whether this research has undergone peer review or if the simulation results have been validated with real-world data or experiments. This information is crucial for assessing the credibility and reliability of the study.

Moderate editing of English language required

Author Response

Responses to Reviewers' comments:

First of all, the authors would like to thank the reviewer for their encouraging feedback and constructive comments on this manuscript. In the following sections, comments will be addressed or clarified point-by-point. Necessary changes made to the manuscript and figures are highlighted in yellow as well.

Reviewer's comments and authors’ responses

Comment 1:  

The research paper lacks context regarding the specific application and significance of the study. It mentions the freezing of pipes in the ground but doesn't explain why this is important or what practical implications it has. Providing some background information or real-world examples would make the research more accessible.

Responses:

It is mentioned in the text 51-58 that the freezing wall shape formed by this traditional straight pipe is more regular and uniform, and fails to produce a targeted reinforcement effect in the area when faced with a weak area with soil and water flow.Arc-shaped freezing single tube formed by the permafrost curtain structure force is more reasonable, higher safety. More importantly, in the actual project encountered in the highly permeable layer of weak area reinforcement, compared with the straight tube to change the "amount", if the same freezing effect requires less arc tube number, more secure and realize a certain economy.

Comment 2:  

The research paper briefly mentions the use of COMSOL Multiphysics software to establish numerical models, but it doesn't provide any details about the methodology, boundary conditions, or assumptions made during the simulations. A more thorough explanation of the research methodology would be essential for understanding the study.

Responses:

Sections 3.2 and 3.3 of the text provided a description of the methods, boundary conditions, and assumptions involved in the modeling process and added a description of the modeling process at 194-200.

Comment 3:  

While the research paper mentions some results, such as the differences in frozen wall thickness between curved and straight pipes, it lacks a detailed explanation of these findings. Readers would benefit from a discussion of the implications of these results and how they relate to the overall research objectives.

Responses:

For a detailed explanation of the results, the authors have added quantitative conclusions on the differences between the freezing walls of curved and straight tubes in the Summary and Conclusions section, see text 20-26, 523-535.

Comment 4:  

The research paper uses technical terms like "long arc ratio s" and "permafrost curtain thickness" without providing clear definitions or explanations. It's important to make sure that such technical terms are defined or explained for readers who may not be familiar with the specific terminology.

Responses:

The long arc ratio s is the ratio of the effective length L to the arc height H. The authors have labeled the illustration in Figure 1. The thickness of the permafrost curtain, which is also the thickness of the freezing wall, is labeled and described at 248-250.

Comment 5:  

Visual representations of the simulation results, such as graphs or diagrams, would greatly enhance the reader's understanding of the findings. Without visuals, it can be challenging to interpret and appreciate the results.

Responses:

The authors have added explanatory notes to some of the visualization results in this paper. See, for example, Figure 4, Figure 12.

Comment 6:  

It's not clear from the research paper whether this research has undergone peer review or if the simulation results have been validated with real-world data or experiments. This information is crucial for assessing the credibility and reliability of the study.

Responses:

In response to the study, members of the author's team are conducting a modeling pilot study. Relevant members of the team have modeled other projects using the same simulation method, which is more consistent with the field data, such as 211-214.Therefore, it is feasible to apply the method.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

The authors have improved the quality of the manuscript by implementing the comments from the reviewers. However,  pronouns such as "we" in the Conclusion section and other parts of the manuscript must be removed. For example: "In this study, we analyze the development and characteristics of the temperature field and seepage field of the single tube and multiple tubes frozen at different arcs" should be changed to "In this study, the development and characteristics of the temperature field and seepage field of the single tube and multiple tubes frozen at different arcs were analysed".

The Quality of the English Language is good.

Author Response

Responses to Reviewers' comments:

First of all, the authors would like to thank the reviewer for their encouraging feedback and constructive comments on this manuscript. In the following sections, comments will be addressed or clarified point-by-point. Necessary changes made to the manuscript and figures are highlighted in yellow as well.

Reviewer's comments and authors’ responses

Comment 1:  

The authors have improved the quality of the manuscript by implementing the comments from the reviewers. However, pronouns such as "we" in the Conclusion section and other parts of the manuscript must be removed. For example: "In this study, we analyze the development and characteristics of the temperature field and seepage field of the single tube and multiple tubes frozen at different arcs" should be changed to "In this study, the development and characteristics of the temperature field and seepage field of the single tube and multiple tubes frozen at different arcs were analysed".

Responses:

Pronouns, such as "we", have been modified and deleted from the conclusion section and other parts of the manuscript. See yellowed portions of the text14,19, ......514-519, etc.

Author Response File: Author Response.pdf

Reviewer 4 Report

The authors have made all the required changes. Hence the MS can be accepted.

Minor editing of English language required

Author Response

Responses to Reviewers' comments:

First of all, the authors would like to thank the reviewer for their encouraging feedback and constructive comments on this manuscript. In the following sections, comments will be addressed or clarified point-by-point. Necessary changes made to the manuscript and figures are highlighted in yellow as well.

Reviewer's comments and authors’ responses

Comment 1:  

The authors have made all the required changes. Hence the MS can be accepted.

Responses:

The revised manuscript has been carefully scrutinized to spot grammatical and topographical errors, the quality of the English writing has been improved.

Author Response File: Author Response.docx