Calculation and Lubrication Characteristics of Cylindrical Roller Bearing Oil Film with Consideration of Thermal Effects
Round 1
Reviewer 1 Report
The paper is of interest and the calculational approach is well described. Some editing of the language is required. I only wonder, why the topic was submitted to coatings and not to MDPI lubricants journal. I think there it would fit better. The format of Figure 10 should be improved.
Author Response
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Author Response.pdf
Reviewer 2 Report
1. Rolling bearings are well-studied objects of mechanical engineering. No new result is visible from the text of the article. The focus should be on the new result. 2. Brief evaluations should be added to the review in order to highlight gaps in this area of research. 3. The presented conclusions are trivial and do not reflect the novelty of the results. 4. How is the critical thickness of the lubricating layer in a bearing calculated? What is the roughness of friction surfaces? 5. An assessment should be made of what are the probable reasons for the differences between the theoretical and experimental results? 6. The layout of the experimental setup should be more detailed. At the moment it is not possible to reproduce the results of the experiment without a sufficient description of the test setup and the experimental procedure. 7. The scatter of experimental results should be indicated in the figure or in another way. 8. In what software were the calculation results obtained? 9. The term "the rolling coefficient" is used in line 164, but the value is 1.28*10^-8 Pa^-1. The piezo viscosity coefficient of the lubricant has similar values. What is the rationale for the choice of lubricant parameters?
Author Response
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Reviewer 3 Report
In this paper, the quasi-static model and heat flow field model of cylindrical roller bearing was established according to the actual working conditions. The influencing factors of bearing lubrication performance were analyzed, and the change rule of bearing lubrication performance considering thermal effect is revealed. The relationship between effective lubricating film thickness and initial position of oil film in bearing contact area was discussed. Finally, an ultrasonic monitoring test bench was built to realize the monitoring and analysis of the cylindrical roller bearing, which verified the correctness of the theoretical calculation results. The descriptions of the methodology and simulation procedures have shown the feature to the research area. Generally, it explains what has been done and what has been discovered. The subject matter is interesting because the paper gives access to the information of this particular research. In summary, this is a piece of acceptable work but it needs some revisions. The paper can be accepted for publication, provided that the following points can be clarified.
The technical features, measuring ranges and accuracy of the measuring devices are not stated.
Missing the general assembly of experimental installation.
The conclusions can be further elaborated: what was the limitation of the study?, what do the study results imply for the larger stakeholders? (policy makers, practitioners, the economic sector, etc. address them one by one), what future study avenues are opened / suggested after this study?
The Abstact part needs to be improved. The authors needs to describe the main results in the abstract.
Please provide the statistical test results. Please indicate how many rounds of trials were conducted? Please also report their variances. Please validate the proposed method on multiple datasets.
I rate the article highly, but I strongly recommend the authors to add some simple benchmarks to the article, thanks to which you will be able to see how much this method is worth.
The results were not at all compared with the research of other authors. It is difficult to evaluate the correctness of the experiments and the results without comparison. It is necessary to find as close as possible research oriented in terms of materials and parameters, because in the present form it is only the presentation of the results.
Author Response
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Author Response File: Author Response.pdf
Reviewer 4 Report
This work presents a modeling framework for the analysis of thermal elastohydrodynamic lubrication (TEHL) in line contacts. This topic was addressed in the Tribology literature several decades ago. The methodology proposed by the authors is not new, nor are the presented results novel. In addition, the paper is poorly written (literature review does not cover any existing numerical TEHL models, and the model description lacks rigor and details), and I’m not sure it even falls within the scope of this journal. Therefore, I regret that this manuscript is not suitable for publication.
Author Response
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Author Response File: Author Response.pdf
Reviewer 5 Report
Manuscript: Lubrication Characteristics of Cylindrical Roller Bearing Oil Film with Consideration of Thermal Effects.
Interesting approach.
Good presentation of the mathematical model of steady-state line contact...
Figure 10 seems to be incorrect or incomplete, can you review that please?
Are authors aware of an additional analysis on viscosity? is this something you could do as next steps regarding this topic.
Authors mentioned conclusions of their work, but, what is the value added of this research or study? can you specify that as a take-away in the conclusion section?
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Dear colleagues! The content of the article has been significantly improved. I wish you success in your further research.
Best regards
Igor Levanov
Reviewer 3 Report
I would like to thank the authors very much for answering the comments and supplementing the missing information from the subject research, which thus increases the scientific level. I agree with them and recommend publishing the contribution in the form presented.
Reviewer 4 Report
The revised manuscript still lacks the novelty level required for publication in Coatings.
