Designing Long-Throated Flumes for Improved Water Management in Rice Cultivation: A New Automated Approach
Round 1
Reviewer 1 Report (New Reviewer)
Comments and Suggestions for Authors1- Please provide the error of the presented method in comparison to known methods in a quantitative manner in the abstract.
2- What is the advantage of the presented method over previous methods?
3- Can the presented method be presented for any channel with an unknown geometry?
4- Suppose the cross-section and geometry of the channel are not trapezoidal, for example, with a compound cross-section. How will you compensate for this deficiency?
5- The manuscript is presented for the special case and trapezoidal cross-section, how can you develop it?
6- Develop the purpose of the manuscript in the first paragraph. Do not use general sentences. Please focus on the topic of your manuscript.
7- The research background is very weak and needs to be strengthened.
8-What are the limitations of the present research?
9- What is the range of Reynolds number and Froude number in the present study?
10- The results of the present study have not been compared with previous research, which is one of the shortcomings of the present manuscript.
Comments on the Quality of English Language
1- Please provide the error of the presented method in comparison to known methods in a quantitative manner in the abstract.
2- What is the advantage of the presented method over previous methods?
3- Can the presented method be presented for any channel with an unknown geometry?
4- Suppose the cross-section and geometry of the channel are not trapezoidal, for example, with a compound cross-section. How will you compensate for this deficiency?
5- The manuscript is presented for the special case and trapezoidal cross-section, how can you develop it?
6- Develop the purpose of the manuscript in the first paragraph. Do not use general sentences. Please focus on the topic of your manuscript.
7- The research background is very weak and needs to be strengthened.
8-What are the limitations of the present research?
9- What is the range of Reynolds number and Froude number in the present study?
10- The results of the present study have not been compared with previous research, which is one of the shortcomings of the present manuscript.
Author Response
First of all, thank you for your comments, as they have allowed us to substantially improve the article. I will try to answer each of them in this document, but additionally, I have highlighted in yellow the modifications I have made throughout the article after reading your report (see document water-3544318-EngEd91750_colors.doc). Other reviewers are colored green and blue.
Comments 1: Please provide the error of the presented method in comparison to known methods in a quantitative manner in the abstract.
Response 1: The proper design of long-throated flumes requires meeting certain conditions, such as: modular flow at both the maximum and minimum flow rates; the Froude number being less than 0.5 upstream of the flume to maintain a subcritical flow rate and avoid surface waves; given that the water depth will rise upstream of the flume, there must be no overflow; and a uniform flow rate as it passes through the flume throat.
Once these conditions are met, the design is considered well-designed. The goal is not to achieve the best design, but rather the appropriate design. For this reason, there are no quantitative comparisons between different designs, as many good designs exist.
However, and in response to the reviewer's comments, the following paragraph has been included in the abstract (line: 31-33):
" The design developed based on our methodology is evaluated using the WinFlume software, and the results obtained demonstrate its strength and suitability."
Comments 2: What is the advantage of the presented method over previous methods?
Response 2: Our main goal is, as we say in the Introduction section (line: 72-75), “to provide a quick and automated design using a spreadsheet that allows direct estimation of the dimensions of the narrowed section of a long throat channel, side slope, and bottom width. We chose the modular limit, sill height, and throat length”
Traditionally, the problem to be solved is to check whether, given the dimensions of the narrowed section, the resulting modular limit is acceptable (see reference 10). In our case, we proceed in reverse, since this ensures that the geometry of the section satisfies the modular limit more in accordance with the characteristics of the channel where the flume is going to be installed and that guarantees the flow measurement in the desired flows range.
In our opinion, once the spreadsheet has been developed, our procedure is faster and easier than the one proposed in reference (11), and, in addition, not just one design but many designs have been tested as shown in Table 1.
Comments 3: Can the presented method be presented for any channel with an unknown geometry?
Response 2: We do not quite understand the question. A long-throat modular flume is designed to fit into a specific channel with a specific geometry. In fact, the long-throated flume geometry is determined by the channel geometry to facilitate smooth transitions between the two, thereby reducing head losses and achieving a higher modular limit.
As already mentioned in our response to the reviewer's third question, the key to achieving a high modular limit is that the geometries of both the channel and the flume are as similar as possible.
4 Comments: Suppose the cross-section and geometry of the channel are not trapezoidal, for example, with a compound cross-section. How will you compensate for this deficiency?
Response 4: In general, if the channel geometry is not trapezoidal, the procedure to follow is the same as that indicated in our paper, except that, where appropriate, the calculations are changed for these different geometries.
Anyway the geometry of the channel cross-section is less important when it comes to designing the geometry of the flume cross-section, as is our case.
If the channel has a compound cross-section, a long-throated flume can be designed with the same cross-sectional shape to ease the transition as we have mentioned before.
When the cross-section of the flume is compound, two flow equations must be used: the first when the water depth does not exceed the geometric height of the lower structure, and the second when it exceeds it.
Comments 5: The manuscript is presented for the special case and trapezoidal cross-section, how can you develop it?
Response 5: When the geometry of the cross section of the flume is different from the trapezoidal, the same methodology can be followed using the flow equation (3) corresponding to that geometry (see reference (3))
Comments 6: Develop the purpose of the manuscript in the first paragraph. Do not use general sentences. Please focus on the topic of your manuscript.
Response 6: Following the reviewer's recommendation, the beginning of the Introduction section has been modified as follows (Line: 40-41):
"This study aimed to develop a methodology for the automated and appropriate design of a long-throated modular flume."
Comments 7: The research background is very weak and needs to be strengthened.
Response 7: We do not fully understand this issue raised by the reviewer. Our research background is supported by open channel hydraulics (see, for example, reference (13)), and we have reviewed and reread the principles used and found no errors.
Comments 8: What are the limitations of the present research?
Response 8: The authors have developed a new and original methodology to design a long-throated flume, using an original inverse procedure, as previously mentioned. It has also been said that the results obtained support this methodology.
Although we believe the work developed is sufficiently substantial to warrant publication, a future complement would be its empirical verification. To this end, in a second phase, we intend to also experimentally evaluate these results. The flume has currently been built, and preliminary tests are underway.
| See image in the attached document |
|
Flume just sited in the field |
Comments 9: What is the range of Reynolds number and Froude number in the present study?
Response 9: The dimensionless number that governs flow in open channels is the Froude number. In our case, it is a structure interposed in a subcritical permanent free flow. Froude numbers are therefore less than unity, and, as stated in our article (line: 195-196), "The Froude number, F, was also confirmed to be less than 0.5 in the approach section for both QM and Qm”, to avoid surface waves that make it difficult to read the upstream gaged head.
The Reynolds number affects the flow in open channels to a lesser extent since the flow is turbulent.
Comments 10: The results of the present study have not been compared with previous research, which is one of the shortcomings of the present manuscript.
Response 10: The best program to date for designing and calibrating long-throated flume and broad-crested weir flow measurement structures is WinFLUME: a Windows-based computer program developed by the U.S. Department of Agriculture. All of our design results obtained using the developed methodology have been compared and certified with WinFLUME.
Author Response File: 
Author Response.pdf
Reviewer 2 Report (New Reviewer)
Comments and Suggestions for Authors1. The content in lines 21 - 23 should be moved forward, and the advantages of this study should be concentrated and placed at the end.
2. The double - citation format in line 29 is inconsistent with the double - citation formats that appear later in the article.
3. The reference 3 is cited multiple times in the Materials and Methods section. Please clarify whether there are issues such as limitations in the research results and a high overlap rate between the main research content and that of others' research in this study.
4. It is recommended to align all the formulas in the article to the left uniformly.
5. For the example illustration in part 3.2 of the article, it is advisable to clarify whether actual examples or simulations are adopted.
Author Response
First of all, thank you for your contributions, as they have allowed us to substantially improve the article. I will try to answer each of them in this document, but additionally, I have highlighted in blue the modifications I have made throughout the article after reading your report (see document water-3544318-EngEd91750_colors.doc). Other reviewers are colored green and yellow.
Comments 1. The content in lines 21 - 23 should be moved forward, and the advantages of this study should be concentrated and placed at the end.
Response 1: You are Wright. The order has been reversed
Comments 2. The double - citation format in line 29 is inconsistent with the double - citation formats that appear later in the article.
Response 2: You are Wright. We have changed to “[1-2].” (line: 42)
Comments 3. The reference 3 is cited multiple times in the Materials and Methods section. Please clarify whether there are issues such as limitations in the research results and a high overlap rate between the main research content and that of others' research in this study.
Response 3: Our research is entirely original, and the methodology developed does not overlap with any other previously described methods. The continued reference to reference (3) is because that publication contains the basic equations for modular gauging and because one of the authors of that work (J. Roldan) is also one of the signatories of this work. We can provide you with a copy of that publication, but unfortunately, it is written in Spanish.
Comments 4. It is recommended to align all the formulas in the article to the left uniformly.
Response 4: The formulas have been aligned to the left uniformly
Comments 5. For the example illustration in part 3.2 of the article, it is advisable to clarify whether actual examples or simulations are adopted.
Response 5: Agree. We have added in the text (line: 293-294):
“for this reason, it was adopted to design our long-throated flume”
Reviewer 3 Report (New Reviewer)
Comments and Suggestions for AuthorsPlease see the attachment.
Comments for author File: Comments.pdf
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report (New Reviewer)
Comments and Suggestions for AuthorsIt seems that the authors have revised the manuscript well and provided appropriate responses to the reviewers.
Comments on the Quality of English LanguageIt seems that the authors have revised the manuscript well and provided appropriate responses to the reviewers.
Reviewer 3 Report (New Reviewer)
Comments and Suggestions for AuthorsThe author did a significant work on revision and most of the comments have been incorporated in revised draft. Now, I believe the manuscript has been improved for onward publication.
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
Comments and Suggestions for AuthorsStrong points:
1. The significant contribution to apply the long-throated flume to irrigation and drainage conditions
2. Design methodology seems consistent and clear
Weak points:
1. Rice crop is out of context of this paper. Note that it is not referred in the Introduction section, what is logic. No sense the title "...of a rice cultivated crop".
2. It seems that no field or laboratory validation work has been developed.
3. No photograph to show the practical work
Reviewer 2 Report
Comments and Suggestions for AuthorsGeneral remarks
Since the procedures for calculating the properties of the long-throated flumes are quite numerous and well known, in this paper it is necessary to clearly show the novelty of the proposed method, its differences from previous methods and the advantages of the proposed method. It is highly desirable to verify the method and demonstrate its accuracy using measurements in long-throated flumes calculated using the proposed method.
The comments along the text
Line 48
“,” after “than”
Lines 67-68
Please, explain all the symbols. The same for all the figures and further along the text. It is difficult to follow the text without such explanation.
Line 82
Please, define the modular limit and its minimum value
Figure 2
Please, show the view on the horizontal plane. Please explain all the symbols, lines of different types and the relationships between the parameters. For example, why kinetic energy was not shown by the arrows?
Line 96
It is not clear what means “p” on the figure 2 at the beginning of the flume
Line 111
Is the assumption H1=Hc valid for the flow without the friction in the flume? Please, prove.
Figure 3
Z, please define here, what is slope – angle or tan of the angle?
Equations 3-5
Please, give the references. Why these equations differ from those in Bos (1978) fig. 7.2. Are they more accurate or easy to use?
Equation 6
Please, show the graph of this relationship with the fitting line for different values of CH . How accurate is this approximation? Is this the main novelty of the proposed approach? – please, indicate.
Equation 10
Are you sure that this is the best approximation of the Bos (1978) fig. 7.3? Please, prove.
Line 128 and further
What is the difference between bt calculated with Eq 8’ (Fig 6) and Eq 14.(Fig 8) Please, explain, what way is better and why the difference is so high?
Line 150 and further
Is it possible to prove that the described procedure is stable and always lead to the same final?
Figure 5
The relationship between l and H/l is evident
Line 256
The consistency of the results obtained, their accuracy and feasibility must be verified by the comparative analysis of measured and calculated characteristics. Are there existing constructed flumes with the dimensions calculated with the proposed procedure? If yes, please, show the measured and calculated depths in such flumes, the existence of the critical regime.
