A Numerical and Experimental Study on an Interconnected Metamaterial for Flexural Vibration Control Based on Modal Strain Energy

Round 1

Reviewer 1 Report

The authors have presented a numerical and experimental study of a flexural vibration control of a plate using ‘interconnected metamaterials’. The study is interesting. I have the following comments on the manuscript.

1. The technical English usage can be significantly improved. There are many instances of paragraphs starting from ‘In this section’, ‘In this subsection’, ‘In section x’.
2. The authors claim to propose “a concept to extract the Bloch mode based on the modal strain energy”. However, it seems this has already been presented in Ref. [17]. This should be clarified.
3. The introduction section needs significant work. Currently, it reads as a description of a collection of papers on similar topics and does not tell a coherent story.
4. The physical mechanisms leading to enhanced wave manipulation abilities of the metamaterials described in the introduction section should be described in detail. For example, in Ref. [3], the enhanced wave manipulation abilities are associated with the dipole resonance of the hard inclusions and multiple scattering of waves between the inclusions.
5. In general, metamaterial designs comprise hard inclusions or cavities in a host medium. Hard inclusions in an elastic medium exhibit dipole resonance and cavities in an elastic medium can exhibit monopole resonance, depending on the material properties. For example, see Sharma et al. Sound scattering by a bubble metasurface, Physical Review B, 102(21), 214308, 2020 and On superscattering of sound waves by a lattice of disk-shaped cavities in a soft material, Applied Physics Letters, 116(4), 041602, 2020. I suggest the authors to include a discussion based on these physical mechanisms leading to enhanced wave manipulation abilities of metamaterials.
6. There are several spelling (e.g. weave instead of wave in the first paragraph of introduction) and grammatical errors (including the usage of the articles) in the manuscript. I suggest the authors carefully proofread the manuscript.
7. In the second paragraph of page 2, “…stamping is so difficult..” must be replaced with “…stamping is challenging…”. The language use must be improved throughout the manuscript.
8. Were the FE simulations performed using an in-house code or a commercial software program? If latter, it is not required to present some of the equation in Section 2.1.
9. Whilst FE simulations were used to design the samples for experiments, a direct comparison between FE and experimental results have not been presented. I suggest the authors to include the FE simulation results corresponding to the experimental results in Fig. 10.
10. Uncertainties are inevitable in manufacturing processes. For example, see Sharma et al. Acoustic performance of a periodically voided viscoelastic medium with uncertainty in design parameters, Journal of Vibration and Acoustics, 142(6), 061002, 2020. How were the uncertainties incorporated in the current study? I suggest including a discussion on the effects of uncertainties on the presented results.
11. In the last paragraph of the introduction, “In this regard,…” should be replaced with “In this work,…”
12. The title of the manuscript can be compressed and made more specific to the presented study.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript authored by Kim et al. describes the suppression of vibration for the plate using an interconnected metamaterial based on numerical analysis and experiment. The manuscript may be of interest to the community. The manuscript can be recommended if the authors address the following concerns:

 

1. As the suppression of vibration due to metamaterial is dependent on the geometric feature of metamaterials such as the size of interconnects and the size of resonator structure, the geometric characteristics of metamaterials have to be delineated. In addition, it would be helpful for readers’ understanding if the authors demonstrate how the geometric feature of metamaterial was determined.

 

2. Though the effect of the geometric feature of metamaterial in the suppression of vibration for the plate may be out of the scope for this article, the authors should discuss how the behavior of vibration suppression is dependent on the geometric parameters of metamaterials in the section of conclusion. The authors might explain how the optimal design of geometric parameters for metamaterial can be implemented.

 

3. The finite element-based simulation shows the vibration suppressions based on two different types of metamaterials such as 5 x 10 and 10 x 10, while the experimental result shows only the case of 5 x 10 metamaterial. Is there any particular reason not to show the experimental result for the case of 10 x 10 metamaterial? It would be good if the authors can provide the experimental results based on both 5 x 10 and 10 x 10 metamaterials, which can be compared with simulation results.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The revised manuscript has most of my comments incorporated. I have the following comments in the revised manuscript which must be addressed before the paper can be accepted for publication.

1. The manuscript contains a number of grammatical errors, including in the title. I suggest the authors carefully proofread the manuscript.
2. The title could be “A numerical and experimental study on an interconnected metamaterial for flexural vibration control based on modal strain energy ”.
3. In lines 35-36 on page 1, Sanchez-Perez et al., Acoustic barriers
   based on periodic arrays of scatterers, Applied Physics Letters, 81, 5240,
   (2002) and Sharma et al., Acoustic performance of periodic composite materials,
   Acoustics 2015 Hunter Valley, Sydney, Australia should also be cited.
4. There are several short paragraphs with just two or three lines. I suggest the authors merge these paragraphs with other paragraphs where possible.
5. My following comment on the original manuscript has not been addressed in the revised manuscript. Please include a discussion on this topic citing some references in the revised manuscript. “Uncertainties are inevitable in manufacturing processes. For example, see Sharma et al. Acoustic performance of a periodically voided viscoelastic medium with uncertainty in design parameters, Journal of Vibration and Acoustics, 142(6), 061002, 2020. How were the uncertainties incorporated in the current study? I suggest including a discussion on the effects of uncertainties on the presented results.”
6. There are several errors associated with the use of the articles.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

As the revision of the manuscript was done with addressing the issues raised by the reviewer, the revised manuscript is acceptable for publication.

Author Response

Thanks for your careful review. 

With your help, the manuscript has been positively revised.

We also got the English editing service and proofread our manuscript.

Thank you.