Optimization of Autoclave Reactors to Improve Bearing Life Using the Taguchi Method and the Response Surface Methodology

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper focuses on studying two key factors affecting the bearing life of a reactor: the number of impellers and temperature. Finite element analysis is used for simulation and optimization, with optimization methods including the Taguchi Method (TM) and the Response Surface Methodology (RSM). A comparison of these techniques reveals that temperature has the most significant impact on the response. Valuable conclusions have been drawn, showing a significant increase of 3.095% in bearing life and a smaller prediction error in RSM's response values. There are areas that need improvement, including:

1.       The introduction should discuss the current state of development and applications of TM and RSM methods in the field of chemical engineering. Explain why these two methods are discussed in the context of optimizing bearing life in this paper.

2.       There are issues in the methodology section. In Figure 4, it is unclear why, after "no result acceptable," the paper proceeds directly to "variable selection." Re-selecting variables or even redoing the Design of Experiments (DOE) is not a reasonable approach and adds unnecessary computational workload.

3.       Please pay attention to the units in the 8th page. Units should not be italicized. Ensure correct representation of MPa (not "Mpa"), and units with division should not have spaces between them. The unit for Joules (Joule) should be capitalized, among other corrections. Carefully review these units.

4.       It's not clear in the main text why "Confirm result" in Figures 10 and 11 is not explained.

5.       How many sample points were used in the Design of Experiments (DoE)? How were they selected? How many times was polynomial regression applied in the Response Surface Methodology (RSM)?

6.       Improve the quality of Figures 15 and 16, including ensuring consistent fonts and sizes, as this significantly affects the overall appearance.

7.       The analysis appears to be shallow. It's essential to delve deeper into the impact patterns and reasons behind parameters and responses based on simulation results. Currently, there are too few conclusions.

8.       The overall quality of the paper needs further improvement, including both the text and analysis. Please carefully review and address the points mentioned above.

Comments on the Quality of English Language

should be improved

Author Response

Dear Reviewer,

We sincerely appreciate your valuable suggestions and comments on the manuscript. We have diligently addressed and incorporated all of your feedback.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

1.) Technical drawings are poor and need major improvement:

 - Figure 3 is not clear;

 - Figure 5 is not clear at all. Please, use the standard engineering presentation for the bearings.

 - Figure 6: please, provide a cross section view of the reactor. In this form the figure makes no sense. Cross section view of the bearing would be preferred.

2.) atm is not a valid SI unit. Provide information in Pa unit.

3.) Lines 154-157: repeated information. Remove it from the text.

4.) equations (1) and (2): please, use a conventional notation for multiplication in this equation.

5.) Methodology: where is practical experiment? Related to bearings, we are talking about small probabilities of failure, i.e 10%, 5% , 2%, 1% etc. How does an improvement in bearing life correspond to a scatter of bearing life? A presentation of numerical simulations is really poor. Where are FE models with BCs? Please, provide them together with the statistics of finite elements and nodes. Which finite element types were used? Where is the finite-volume model with its BCs? Please, provide it. Provide the material data for numerical simulations in table. Figure 9: This is not a decision tree, but a very simplified description of the fatigue analysis. It adds no value to the article. Figure 10 and 11: what is the objective function? Is it bearing life?

6.) Line 217: put the title on the next page.

7.) Page 7: CCD design - what was its layout? Box-like or sphere-like?

8.) Equation (3): what is the R2 value of this model?

Comments on the Quality of English Language

-

Author Response

Dear Reviewer,

We sincerely appreciate your valuable suggestions and comments on the manuscript. We have diligently addressed and incorporated all of your feedback.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

All comments have been carefully considered and errors have been revised.

Author Response

We are grateful to the reviewer for accepting the comments and our response for review. Your support is much appreciated.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have ignored most of the important questions raisied and made only minor improvements to the article. There still many issues open:

1.) No improvements related to the cross-sections of machine elements and components.. Do the authors understand, what is meant by the cross-section view (standard for technical drawings)?

2.) No significant improvements related to a description of FE models: Where are FE models? Please, provide them together with the statistics of finite elements and nodes. Which finite element types were used? Where is the finite-volume model with its BCs? Please, provide it. Provide the material data for numerical simulations in table. Figure 9: Again, this is not a decision tree, but a very simplified description of the fatigue analysis. Where are the data that are needed for fatigue analysis? S-N curves? E-N curves? Their parameters? It adds no value to the article. Figure 10 and 11: what is the objective function? Is it bearing life?

3.) The authors are still using a symbol for a vector product for a simple multiplication.

Author Response

We are sincerely thankful to the reviewer for providing valuable comments and suggestions to enhance the manuscript. The revised manuscript now encompasses all the comments and suggestions, which has significantly improved its quality. Your feedback has been invaluable, and we greatly appreciate your assistance in enhancing the content.

Author Response File: Author Response.docx

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

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