The Actuating Characteristics of Magnetorheological Fluids Subjected to Particle Sedimentation and Temperature Variation
and Seung-Bok Choi 4,5,*Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors of the review paper present the results of a study in which they examined the characteristics of MR fluids subjected to sedimentation and temperature. I believe the results are of interest, however, at the same time I would welcome some corrections to the manuscript.
- General comment: improve the quality of the illustrations. Specifically, improve the formatting of the labels and the annotation of the MATLAB figures. Apply same formatting (text size and font) to the text in the illustration as in the main text.
- Improve the introduction. Specifically, analyze the sedimentation rate measurement methods, starting from visual assessments to those based on the measurements of electrical conductivity or inductance, etc. Try to answer the question: is sedimentation always worth preventing? What is better - a fluid with a low sedimentation rate or a fluid which settles down quickly (has a high sedimentation rate) but may recover quickly even after the prolonged inactivity?
- What is the reason for not including any low/sub-zero temperatures? May the authors include any zero or sub-zero temperatures?
- In the magnetic analysis section provide the reference for the material data sheet of the Lord MR fluid used
- Try combining the plots 6a-c into a single plot
- Provide a picture/sketch of the damper in section 3.3.
- MR damper are known for generating high intercept force at zero velocity if no hydraulic bypasses are used. The simulated behaviour at 0 m/s is then incorrect and should be altered. Also, there is no need to show the output at such high speeds as in real dampers the contribution of quadratic (flow) losses becomes significant. Perhaps it would be better to operate in terms of (relative or absolute) dynamic range rather than force-velocity static characteristics.
Overall, my recommendation is major revision. The material included and the conclusions drawn are sound, however, some corrections are needed. The authors should revise te paper as needed and resubmit.
Comments on the Quality of English Language
The quality of the written text is sufficient.
Author Response
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Reviewer 2 Report
Comments and Suggestions for AuthorsThe manuscript is interesting, but some corrections and improvements must be addressed.
Line 114 writes, "a finite element analysis, followed ...".
Please refer to "magnetic flux density" in the manuscript when describing values measured in Tesla. Check the entire manuscript.
The sub-section 2.1 has many technical errors. It must be corrected and rewritten. For example, the phrase "The guide arm to generate a magnetic field was used as steel 45C, while the magnetic circuit was used as copper (1 mm diameter) that wound around the steel bobbin with 500 turns. Then, the current inputs of 1 A and 2 A were applied to the magnetic circuit." must be reformulated. A guide arm cannot generate a magnetic field, a magnetic circuit cannot be made of copper, and a current cannot be applied to the magnetic circuit.
Add some information about the mesh used in FEM. Reformulate "The meshing result and simulation results are depicted in" because, in Fig. 2, no mesh is presented. Change the caption for Fig. 2 accordingly, or insert a picture with the geometry combined with the mesh used.
Insert some information about the electromagnetic properties of the 45C steel to better understand the FEM problem.
Reformulate "each position of the magnetic device" because there is no displacement of the magnetic circuit.
Add a vector plot for B to Fig. 3 to present the adding fields better.
In Fig. 5, explain what the "magnetic device" is and why it is different from the three guides.
Reformulate the sentence "However, this work was only focused on the top position of the tube, while the proposed test in this work was conducted in three positions ...". This work is with one or with three positions?
Change the caption from Fig. 7 to explain the right schematic.
Check Fig. 8 horizontal axes. Must be Time (hours).
Comments on the Quality of English LanguageSection 2 requires extensive English language corrections.
Author Response
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Reviewer 3 Report
Comments and Suggestions for AuthorsIn this paper, the authors experimentally investigate the sedimentation behavior of MR fluids under the different controlled temperatures (25, 50, 70°C) for a long-term period with the applied current inputs of 0, 1, 2 A using a multi-guide-arm magnetic device. The results reveal that experimental parameters of lower temperature and higher current input result in the highest sedimentation rate. This study also discusses the rheological properties (viscosity, shear stress, yield stress) of the MR fluids before and after the sedimentation experiment. The contributions and highlights of this manuscript are obvious, and I recommend this paper to be published at the Journal of Actuators.
Author Response
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Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe revised manuscript is fine. I accept the paper for publishing in the journal.
One comment:
Equation 2 omits the friction forces and the gas force due to the accumulator. They should be added to the equation or proper assumptions be made in the text. Otherwise, the manuscript is fine.
Comments on the Quality of English LanguageIn general, English is fine. There are some few minor grammar mistakes.
Author Response
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Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors addressed all the suggested corrections.
Comments on the Quality of English LanguageThe overall English level is good.
Author Response
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