PONE-D-24-10956An improved calculation method for dry modal analysis of four-stage centrifugal pump rotor system based on concentrated mass methodPLOS ONE

Dear Dr. Gao,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

 In addition to reviewers' comments, the authors are suggested to consider following points:(i) Abstract should be improved to avoid repetition of text(ii) Contours in Figures 3 and 6 are not of good quality. The values on color map are also not clear.(iii) The comparison with experimental studies should be included in the revised paper.(iv) The differences with the previous similar papers (Refs. 11 and 29) of the author need to discussed in detail.

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Muhammad Shakaib, PhD

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Partly

Reviewer #3: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: No

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: No

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Reviewer Comments

In this paper, a simplified concentrated mass mathematical model was employed to enhance the accuracy of modal analysis using the concentrated mass method for a four-stage centrifugal pump rotor system. A modal analysis of a four-stage centrifugal pump rotor system with a balancing disc was conducted using both a simplified concentrated mass model and Ansys. By analyzing the differences between the two calculation results, correction coefficients based on the mass and flexural stiffness, which affect the modes of the system, were introduced. Subsequently, an improved mathematical model based on the concentrated mass method was proposed. However, the followings should be carefully addressed in the revision to be published in your journal.

1- The authors should be followed the instruction of the journal in all parts and sections in this manuscript.

2- Complete mathematic calculation model with all nomenclature missing. Please check the number of each section, equation, and chart.

3- The abstract needs more quantitative results. The abstract section is an important and powerful representation of the research. It is better that the results should be presented with the support of specified data. Please provide your contribution and work novelty.

4- The authors should indicate this technique to enhance system performance. Also, the author should add more references that discuss the effect of using this technique. It is recommended that the authors carry out wide analysis and comparison with the state-of-the-art studies.

5- Most tables and figures are needed improve the quality of all tables and figures.

6- Add references for all equations.

7- I would also expect to validate with two more experimental works available in the literature.

8- The literature review must be improved. 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 (literature review should be extended and add below references). Evaluation and Investigation of Hydraulic Performance Characteristics in an Axial Pump Based on CFD and Acoustic Analysis. Investigation of the Main Flow Characteristics Mechanism and Flow Dynamics Within an Axial Flow Pump Based on Different Transient Load Conditions. Effect of Different Guide Vane Configurations on Flow Field Investigation and Performances of an Axial Pump Based on CFD Analysis and Vibration Investigation. Investigation of the Influence of Varying Operation Configurations on Flow Behaviors Characteristics and Hydraulic Axial-Flow Pump Performance. Investigation on the Characteristics of Internal Flow within Three-Dimensional Axial Pump Based on Different Flow Conditions. Experimental Diagnostic of Cavitation Flow in the Centrifugal Pump Under Various Impeller Speeds Based on Acoustic Analysis Method. Experimental and numerical investigations on the cavitation phenomenon in a centrifugal pump. Investigation of effect of pump rotational speed on performance and detection of cavitation within a centrifugal pump using vibration analysis.

9- You need to add error analysis of your results and add the error bars in your graphs to indicate your accuracy measurements.

10- Improve work justification. Also, add more analysis about velocity and pressure contours.

11- More quantitative conclusions should be presented. Please prepare additional comparisons, some percentage differences. There is a lack of quantitative conclusions which should contain main findings from the paper and highlight the new and high novelty and contribution of your work to the field.

12- Present the mathematical equation of the boundary conditions and initial condition.

13- I would also suggest including in the conclusion section but also in several other places in the manuscript discussion and comparison with findings from other authors with similar published research work.

14- The conclusion section on lacks in summative conclusions. The main results, novelty and academic contributions should be emphasized in this section. Moreover, are the results obtained in this paper really applicable in other similar researches?

15- In the discussion development, it is very important to emphasize points of agreement or disagreement between results in this work and others cited in references part of manuscript.

16- Authors should discuss limitations of the current study and possible improvements for future directions/research works. Authors are requested to check the reference format and correct some inconsistent formats.

17- Finally, I strongly recommend the author to read through the whole text and correct it to make it more reader-friendly.

Reviewer #2: In this article, a four-stage centrifugal pump rotor system model is established based on the basic of material mechanics and gives the inherent characteristics and modes of the structure through characteristic analysis. Meanwhile, the results are verified by comparing with Ansys and pointed out that the accuracy is obviously improved by the calculation method in the article.

There are several points that need to be improved and considered.

1. Some variables need to be indicated in italics to avoid misunderstandings.

2. The pictures in the article are blurry, a clearer picture will help to understand the contribution.

3. The author mention that this is an improved method, but just consider the division of the mass more carefully in the mass matrix and consider the stiffness of the impeller in the stiffness matrix after optimization. Calling it an improved method requires careful consideration.

4. In this article, only Ansys result is used for verification, if a comparison with experimental result is made will become more convincing.

5. The derivation and analysis generally is lack of innovation and the form of computation result is too simple which should be significantly improved.

6.

Reviewer #3: The authors studied a four disks rotor system. The natural frequency for the original and optimization system are studied and compared with the FEM simulation. For my opinion, the paper a little bit simple, and more like a report. At this situation, I think the paper can not be accepted.

Some comments are list as following.

1 In table 2, it’s hard to find the new nature frequency. It’s a simple copy of table 1.

2 What the key point for the authors to show the model shape again. I think the original, FEM and optimization system should have similar mode shape.

3 Usually, the first nature frequency should very close to the FEM and experiment results.

4 For a high-quality paper, I think a simple experimental verify is needed.

5 Novelty needs to be explicit in abstract.

6 Expand figure captions so figures are almost self-explanatory.

7 Broaden and update the literature review to better connect to the current effort in the field in the context of mechanical sciences; for papers like this one we expect no less than 40 journal papers including 15 recent ones to be critically discussed. Do not cite text books or manuals.

8 Conclusions should be stronger.

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Reviewer #1: Yes: Ahmed Ramadhan Al-Obaidi

Reviewer #2: No

Reviewer #3: No

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Improved calculation method for dry modal analysis of four-stage centrifugal-pump rotor system based on concentrated-mass method

PONE-D-24-10956R1

Dear Dr. Gao,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Muhammad Shakaib, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: (No Response)

Reviewer #2: All comments have been addressed

Reviewer #3: (No Response)

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The followings should be carefully addressed in the revision to be published in your journal.

1- The abstract needs more quantitative results. The abstract section is an important and powerful representation of the research. It is better that the results should be presented with the support of specified data. Please provide your contribution and work novelty.

2- The authors should indicate this technique to enhance system performance.

3- Add references for all equations.

4- Improve work justification. Also, add more analysis about velocity and pressure contours.

5- More quantitative conclusions should be presented.

Reviewer #2: Review of "Improved calculation method for dry modal analysis of four-stage centrifugal-pump rotor system based on concentrated-mass method". This paper improve the accuracy of modal analysis for a four-stage centrifugal-pump rotor system with a balancing disc based on the concentrated-mass analytical method, and a simplified concentrated mass mathematical model and an ANSYS simulation model are established. The results from these two models are reasonable now. On the whole, the authors have address the former comments.

Reviewer #3: The authors had done a good work now. By considering the pre-review reports, I think this paper can be accepted at this situation.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Ahmed Ramadhan Al-Obaidi

Reviewer #2: No

Reviewer #3: No

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