Wheeled Capsule Threshold of Motion at Different Locations in a Horizontal Bend Pipeline Based on Hydraulic Capsule Pipeline Transportation
Round 1
Reviewer 1 Report (Previous Reviewer 4)
Authors have incorporated all the suggestions and queries of the previous reviewers. However, some of the points are not yet addressed. They are:
1) Figure 7 is still not clear, and the vectors are not visible. I suggest to enlarge each sub-figures separately.
2) Figure 7e is missing
3) Figures 8, 9 and 10, what the authors mean about first, second, third and fourth conditions? Do they indicate the position of the capsule with angles? If so, please mention the same.
4) LInes 311 and 312, both "the upper-half flow direction pointed upstream via a right-handed helix, but the lower-half flow direction pointed upstream via a right-handed helix" can be expressed as "both the upper-half and the lower-half flow direction pointed upstream via a right-handed helix".
5) Conclusions are not reflecting the results.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report (Previous Reviewer 3)
- Additional reading by an English editor would be required. While the language use has been drastically improved from the previous submission, some moderate English corrections might still be applicable.
- The image quality for Figure 7 appears poor. Might need to be improved.
Author Response
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Author Response File: Author Response.pdf
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Dear Authors,
In this manuscript the problem statements agree with the title and have significance. The methods used to gather the data for this article were clearly explained. Overall, it was a very interesting, significant contribution to this field of research. Hydraulic Capsule Pipeline Transportation is in my opinion a green transportation method without consuming of fossil fuels. In this manuscript the physical experiment, numerical simulation and theory analysis were used for the flow characteristics during the wheeled capsule start-moving in the horizontal pipe. The result showed that during the capsule starting, the variation of flow was mainly focused on the downstream of the capsule, while other zones indicated the same tendency that the velocity magnitude was larger near the outer bend than the inner bend of the pipe. I think these result can provide some references for the application of Wheeled Capsule Pipeline Transportation. In my opinion the quality of citations is good, autors have referenced the interesting works in this field of research. The topic is interested and the result are concreted and useful for the scientific community, however, some aspects must be revised before the acceptation for this Journal.
Thus, the topic is very interested, however, some aspects must be revised before the acceptation for this Journal. The results aren't well presented, especially the graphs and diagrams- are too small or unreadable (Fig. 6, 7). The editorial quality of the manuscript needs to be improved, too. Some specific comments are listed below.
1. Charts and diagrams need correction - see Figures (esspecially Figure 6, 7) are invisible and thus difficult to interpret,
2. In line 166 appeared sign bettwen point (d) & (e) I think only need to comma
3. Check in manuscript the typos and spaces, and the size of the space between lines (especially in references).
4. Abstract: The aim and conclusions of the study must be clearly visible. Please improve the writing style and the mention the significance of the study in one sentence.
5. The purpose of the study should be clearly stated at the end of the introduction, preferably with hypotheses tested. The text in finish of introduction is vague and does not reflect the content of the study, in my opinion.
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
Paper is focused on the topic of hydraulic capsule pipeline transportation. The experiment and numerical simulations were done to provide some references for the application of wheeled capsule pipeline transportation that is “a green transportation method without consuming of fossil fuels” (referring to the abstract).
Paper lies in the scope of journal and seems to be interesting to the Readers.
The experiment should be better described and other major comments should be addressed before taking the paper into consideration for publication:
1) The abstract should be rewritten. The conclusions are cited and listed in a one very long sentence. Please make it more fabular and shorten into a few sentences to better understand the abstract.
2) In my opinion title should be changed to highlight the practical application of the investigations. In the abstract one can read that the paper is about capsule pipeline transportation / hydraulic capsule pipeline transportation. It should be better highlighted in the tittle also. Then the Reader would be more interested if energy efficient solutions or transportation methods are in the scope of his interest.
3) Please highlight in the literature review the differences between previous papers and your paper. Please clearly indicate the knowledge gap and prove that it is a really not analyzed area of the field. Please indicate new approach / new methods in a comparison to the existing investigations.
4) Please extend the introduction and add more information about the rule of operation of the system. Please highlight the role of the water of system (the paper is directed to the “Water” journal). Please specify typical parameters under it is working to make better background of the study and to present the investigated system to the Reader that can be not so familiar with it and would like to know how does it work.
5) Line 72. “The physical model of wheeled capsule is shown in figure 1” and should be “The physical model of wheeled capsule and it’s schematic diagram are shown in figure 1.”
6) Point 2.2. Experiment – please add more information about the measuring apparatus and its precision. Please put the dimensions, the lengths of the entrance sectors on the graphs / schemas/ Please indicate the location of the measuring equipment. Please specify in the table the initial conditions – what parameter and in what range where changing?
7) Fig. 7 is not clearly readable. Please change it – maybe it should be larger?
8) Conclusions should be enriched with the practical implications. The velocity field was analyzed, but what is the implication for the practice? Something should be changed? If yes, what should be done? Is it good or wrong? What does an observation affect in practice?
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
The paper presented tries to describe the flow characteristics around a wheeled capsule hydraulically pushed through a bend pipe. My observations on the submission are as follows:
1. The paper needs heavy editing of the English language before it can be considered. It is extremely difficult to read, to the point that some of the idea that are being communicated cannot be understood.
2. The introduction needs to be rewritten to convey not only a list of previously related works, but what important conclusions were reached in those works and what are the areas where further analysis is needed.
3. The paper seems to be concerned with the starting conditions of a capsule transport within the flow inside a bend pipe. How realistic is this scenario? Why would a capsule transport design be developed with a bend at the starting point, rather than a standard straight section. If bends are needed, they could be placed downstream where the capsule motion has reached steady state.
4. Explain the choice of the 0.1 m diameter pipe. Is this value specifically relevant for a particular application? The same question applies to most of the dimensions listed in the manuscript.
5. What numerical package was used for the simulations in Section 3?
6. In figure 6, what is the axial velocity referring too: the velocity of the capsule or the velocity of the fluid?
7. In figure 5, there is no explanation of what are meshes (b), (c) and (d) referring to.
8. The image quality of Figure 7 is too poor to infer any meaningful information. Also, is the data presented the result of simulations or of the experiment?
9. Is the data presented in Figure 8, Figure 9, and Figure 10 the result of simulations or experiments?
10. The Section 4 and Conclusions describe only visually the velocity profiles. However, there is no in-depth discussion of the effect on these velocity profiles to the motion of the capsule, and how can one use this information to inform an optimal design of the system.
Author Response
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Author Response File: Author Response.pdf
Reviewer 4 Report
After thorough review of the manuscript, I found that the manuscript needs major revision and grammatical corrections. The queries are:
1) Authors mention at many places (Line 16, 220 for example) the clockwise and counterclockwise. These are not appropriate directions to mention, because clockwise from one side becomes counterclockwise from other side. Hence needs change.
2) Introduction section needs to be completely revised.
3) What are the dimensions of wheeled capsules (diameter, length)?
4) Give the details of PIV (Laser details, image processing details).
5) In Figure 4 mention all sections (3 on upstream, 5 on downstream and 5 on gap) as mentioned in the text.
6) At many locations, sentences are incomplete (Example - line 127 to 129, 152-153).
7) Line 131, 'mu' id dynamic viscosity "not number"
8) Replace "uncompressible" by "incompressible" (Example - Line 137)
9) Line 140, fluctuating velocity components ui' and uj'.
10) Figure 7, vector diagrams are not clear. Give zoomed ones.
11) Discussion sections needs to be changed giving the details of velocity magnitudes. Only mentioning larger, smaller do not highlight the results.
12) Figures 8,9 and 10, what is the meaning of first, second, third and fourth condition? They are not clearly mentioned.
13) Line 185, what is the meaning of "serve"?
14) Lines 204-205, how to identify upstream and downstream of capsule?
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Authors took into account all my comments.
Especially the abstract is well rewritten and the introduction is really improved thanks to the comparison of the actual work with previous papers and thanks to suggested highlighting of the differences in methods. Knowledge gap is better presented and justified. What is more, more focus is given on the practical application of the results what significantly improve the readability of the paper. The change in the title of the paper should be also considered as a good move.
In my opinion paper is significantly improved and meets the expectations of the journal about the quality and scientific reliability. I do not have any farther comments.
Reviewer 3 Report
The updates made to the paper, have improved the quality of the presentation. With that said, based on the added understanding of the flow of the work described I have the following observations:
*Minor observations:
- Many figures do not seem to be aligned or scaled properly relative to the width of the paper.
- I am not sure if including Figure 5, brings any new information that could not be included in written form in the manuscript.
- The quality of Figure 7 is poor.
*Major observations:
- The experimental data seems to be used only as part of the numerical validation in Figure 6. If that is the case, clearly specify that, at the beginning of the Section 3, for clarity.
- In Figure 6. (b), (c) and (d) there are “test” points that fall out of the simulated range. Explain why is that.
- The language and write-up of the manuscript still require very heavy editing.
Reviewer 4 Report
Comments for author File: Comments.pdf
