Local Modal Frequency Improvement with Optimal Stiffener by Constraints Transformation Method

Round 1

Reviewer 1 Report

Your work about Modal Frequency Improvement with Optimal Stiffeners is relevant and interesting.

There are still some issues to be resolved.

1. Line 24) spelling: issue
2. Line 118) variable is missing
3. Copy and paste error: Equations (5), (6) and (7) are identical
4. Line 132) variable is missing
5. Line 135) variable is missing
6. Line 136) variable is missing
7. Line 143) word is missing: It can be evidenced from the final …
8. Line 185-188) The reader should be potentially able to reproduce the same work of Authors. 

You write that obtaining nodal equilibrium forces of local mode and establishing static load condition in FE model are two difficult and important issues you solved with FE-Analyses (Msc. Patran/Nastran). Please explain in more detail.

9. Discrepancy between text and figure caption:

Line 273) Figure 10 showed the local modal shape of the horizontal plate.

Line 278) Figure 10. Static nodal displacement of the optimized model.

10. Line 285) directly from Figure 9 10 and Figure  10 11,
11. Line 287) “A rectangular stiffener was placed at where the maximum displacement occurred”

The arrangement of the stiffener is not clear to me. It seems, that there are two stiffeners (Fig.12), but one stiffener over both displacement peaks would also be imaginable. Please describe the arrangement exactly or attach a sketch.

12. Line 299) “The weight of stiffener was accounted for 0.043% of the initial weight.”

Wouldn't it be more correct to relate the mass of the stiffener to the mass of the plate (local mode) rather than the total mass of the satellite?

13. Line 334) Intercalation International Journal
14. Line 336) Sigmude Sigmund

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 2 Report

Thanks for inviting me to evaluate the article titled "Local Modal Frequency Improvement with Optimal Stiffener by Constraints Transformation Method" The reviewer would like to recommend publication of this paper in the journal after major revision and some improvement.

1. It has to be described why Constraints Transformation Method is better than other methods for structural optimization problem with local frequency constraints. In addition, what is the benefit of this method? (Abstract, Introduction, Example, or Conclusions)
2. Please add the convergence analysis to the case of finite element analysis in this paper.
3. It seems that only numerical examples are provided to confirm the validity of the proposed method. No experimental verification to elaborate the characteristics of the Constraints Transformation Method. The author should demonstrate the effectiveness of the proposed method in practical structural system in this paper.
4. Many incomplete sentences should be modified, eg. The sentences around equations (5), (8), (12), and (16). Also, the “Where” under equation (5) should be lowercase and there is no need to start a new paragraph. Please make the final confirmation on the full text in final version if accepted.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Dear authors,

thanks for the corrections and additions.

Kind regards

Reviewer 2 Report

I am satisfied at all replies of the authors.