3D Printing of Composite Material for Electromechanical Energy Harvesters
Round 1
Reviewer 1 Report
Paper entitled with “ Concept of a new ferromagnetic composite material suited for 2
manufacturing of small electromechanical energy harvesters using 3D printing techniques” by Wojciech Burlikowski, et al proposed material could be used in manufacturing of small electromechanical devices such as energy harvesters. The following comments are rising:
- Title: concept of new ..title is so long and more descriptive . 3D printing of composite material for electromechanical energy harvesters ..is proposed
- Introduction, wondering that there are no any reference listed , Energy harvesting examples of materials and devices in review .. https://doi.org/10.1109/TMTT.2017.2660487, Nano Convergence volume 8, Article number: 37 (2021) , Materials Letters Volume 306, 1 January 2022, 130965, Environmental Nanotechnology, Monitoring & Management Volume 14, December 2020, 100314.
- In page 2, line 55 : “First, in chapter 2, the research in the field of magnetic composites is thoroughly analyzed” to what chapter authors refer. Similarly … Then in chapter 3 an idea of a new magnetic. Page 3. Line 98 .. In the work [3], which work refer to.
- There are lack of experimental work that would strongly support the FEM and the study concept.
- Authors need to compare their finding and mathematical model with other reported work.
- References 17 , consider the good start to perform experimental work to support the FEM.
- References 20 and 21 can not be a list of reference for research paper.
Author Response
Dear Reviewer,
thank You for reading the paper and for Your constructive remarks.
Title of the article was changed according to Your suggestion. Also, the bibliography was improved - some positions were removed and we added articles regarding application of SMC, including the one suggested by You. We are also aware that the article lack experimental results, but the article describes the idea of a new composite and initial study of its properties. Exeprimental work is the scope of further work.
Yours sincerely,
Authors
Reviewer 2 Report
The authors report the new ferromagnetic composite material suited for manufacturing of small electromechanical energy harvesters using 3D printing technology. The novel composite based on ferromagnetic wires immersed in a polymer material for additive manufacturing technology was reported. In addition, magnetic properties of the materials were examined using FEM for manufacturing of small electromechanical devices such as energy harvesters, for applying 3D printing technique this study. This experimental verification report interesting technology and well-presented in future research topic. However, there are some grammatical errors, and expressions are also eccentric.
My recommendation the manuscript is acceptable in the present form.
Author Response
Dear Reviewer
Thank you very much for reading our paper and sending your opinion. Thanks to this we can improve our paper and it will inspire us for further scientific work.
Your sincerely,
Authors
Reviewer 3 Report
1) Too much story and general description in the summary, shorten the summary and introduce some concrete results in it so that the reader knows from the beginning some clear news brought by the paper.
2) Please give more explanations regarding equations 1 and 2, as well as the model used.
3) Figure 2 requires further discussion.
4) An additional discussion is needed in paragraph 3.1 and in figure 3.
5) An additional discussion is needed in Figures 5-6 and the data in Table 1.
6) Section 4 discussions should be developed by adding all the advantages of the new methods presented. Comparisons with known classical methods will be discussed here, especially those studied by the authors, but the possible limitations of the proposed new method will also be presented.
More explanations of possible experiments to verify the accuracy of the theory and simulations would also be needed.
7) For a such hot topic studied lately, a more extensive bibliography would be needed.
8) The programs used, and the calculation algorithms should be presented in more detail in the methodology or in an appendix of the paper.
9) Insert a conclusions section that presents all the main ideas of the paper in the form of conclusions.
Author Response
Dear reviewer,
thank You for reading our paper and for Your constructive remarks. The answers for Your keypoints are listed below:
Ad 1) Abstract was shortened and rewritten according the the reviewer's suggestion.
Ad 2) and 8) Equations and their description was improved in accordance to the suggestion. As for the model, in our opinion the description given in sec. 2.2 (lines 226-275) and 2.3 (lines 294-302) gives a good insight into the adopted procedures. Both packages used in the analysis are well known. I think the problem the reviewer has in mind is something which is beyond our expertise as we are not software developers but users. We just tried to adopt those packages to define our problem. We are, however, aware that it is a difficult problem for the ferromagnetic composite with magnetic powder to be modelled using FEM. It is very evident in an extremely big difference in obtained results for two adopted models. First experimental trials also prove that: contrary to success in production of PM based on powder technology, in case of ferromagnetic material this technology is not feasible. Main reason is that in case of PM made of rear earth materials their permeability is close to permeability of vacuum, which makes the powder almost homogenous when permeability is concerned. Step change of permeability in the mesh created for magnetic powder from subregion to subregion is just an extremally difficult problem to analyse. Similar problem is well known in the analysis of torque in rotating electrical machines where a slot-tooth structure is present, also featuring step change of magnetic properties [Meunier G., Finite Element Method for Electromagnetic Modelling, chap.11.4.4]. This difficulty makes it even more evident that the proposed new magnetic composite with continuous wires (chapter 3) is more reliable. It is much easier to describe in FEM model than the composite one and therefore we used only AED software to analyse its properties. The two models based on EMAG and MAXWELL were used for the analysis of magnetic powder only to exemplify the previously mentioned numerical challenges. It is quite possible that it would be necessary to create a special type of elements to account for the that type of behaviour, like eg. thin or line regions [Meunier, chap.6.6.2].
Ad 3) A short explanation of the material characteristic obtained with the MAXWELL model was added as suggested, which clarifies the reasoning that leads to the idea of a proposed composite.
Ad 4) Brief description of the Figure 3., as well as a description of some advantages of the proposed appropach from the technological point of view was added to the article.
Ad 5) The data in the Table 1 were extended and include 3 materials having ferromagnetic properties, that are reported in the literature. Two of those are commonly used materials, while the last one is a composite made of iron powder bonded with epoxy resin. The properties give a good background to the presented results obtained with a simulation and are a valuable addition to the analysis, as suggested by the reviewer.
Ad 6) In the discussion a clear niche of the proposed composite i.e., its possible application in 3D printing technology, was highlighted.
Ad 7) Bibliography was extended, adding positions devoted to applications of SMC composites and two articles describing challenges in FEM modelling of systems where a big difference of magnetic permeability is present at the boundaries of elements that the geometry consists of.
Ad 8) In our opinion the description given in sec. 2.2 (lines 226-275) and 2.3 (lines 294-302) gives a good insight into the adopted procedures. Both packages used in the analysis are well known. I think the problem the reviewer has in mind is something which is beyond our expertise as we are not software developers but users. We just tried to adopt those packages to define our problem. We are, however, aware that it is a difficult problem for the ferromagnetic composite with magnetic powder to be modelled using FEM. It is very evident in an extremely big difference in obtained results for two adopted models. First experimental trials also prove that: contrary to success in production of PM based on powder technology, in case of ferromagnetic material this technology is not feasible. Main reason is that in case of PM made of rear earth materials their permeability is close to permeability of vacuum, which makes the powder almost homogenous when permeability is concerned. Step change of permeability in the mesh created for magnetic powder from subregion to subregion is just an extremally difficult problem to analyse. Similar problem is well known in the analysis of torque in rotating electrical machines where a slot-tooth structure is present, also featuring step change of magnetic properties [Meunier G., Finite Element Method for Electromagnetic Modelling, chap.11.4.4]. This difficulty makes it even more evident that the proposed new magnetic composite with continuous wires (chapter 3) is more reliable. It is much easier to describe in FEM model than the composite one and therefore we used only AED software to analyse its properties. The two models based on EMAG and MAXWELL were used for the analysis of magnetic powder only to exemplify the previously mentioned numerical challenges. It is quite possible that it would be necessary to create a special type of elements to account for the that type of behaviour, like eg. thin or line regions [Meunier, chap.6.6.2].
Ad 9) Conclusion section containing key points of the paper was added at the end as suggested by the reviewer.
We hope that the made improvements fulfill Your comments on the paper.
Yours sincerely,
Authors
Round 2
Reviewer 1 Report
Please check this paragraph again and correct it .
- In page 2, line 55 : “First, in chapter 2, the research in the field of magnetic composites is thoroughly analyzed” to what chapter authors refer. Similarly … Then in chapter 3 an idea of a new magnetic. Page 3. Line 98 .. In the work [3], which work refer to.
- support equation 1 and 2 with references
Author Response
Dear Reviewer,
thank You once more for Your remarks.
In accordance to the first one, a descritpion of the paper organization in the "1 Introduction" section was changed to be more clear.
For the second of Your remarks, the goal of the presented calculations is to obtain averaged magnetization curve of the simulated composite. In that sense, integral quantities are calculated using FEM models, followed by the assumption that the result comes from the uniform distribution of the local values, i.e. H and B vectors. While this is not true generally, such an approach is natural in engineering calculations regarding averaging process and hence is widely used. In the paper a thought process behind those calculations is presented in section 2.2., page 6, lines 254-261. Other than that, presented calculations are based on standard definitions and equations regarding electromagnetic quantities, that can be found in numerous handbooks on electromagnetics. In this light authors believe that the reference to one of such handbook is not necessary.
We hope that these answers are sufficient to clarify Your doubts.
Yours sincerely,
Authors
Reviewer 3 Report
The work in the revised version can be accepted for publication as a theoretical study with simulation, obviously without an experimental part to confirm the proposed theory.
Author Response
Dear Reviewer,
thank You again for Your remarks and time spend on reviewing the paper.
Yours sincerly,
Authors
