Experimental and Numerical Study on Stress Distribution Characteristics of Traveling Wave Resonance of High-Speed Bevel Gear in Aero-Engine
Round 1
Reviewer 1 Report
The authors analyzed and presented a gear traveling wave resonance characteristics and stress distribution characteristics of high-speed bevel gear in aeroengine. But it is difficult to find the novelty of the work.
In abstract, what do you mean by the dangerous speed in “the TWR fatigue failure monitoring experiment of the central drive bevel gear in an aero-engine is carried out, and the TWR frequency, dangerous speed, dynamic stress and fatigue fracture characteristics of driven bevel gear are obtained.”
The abstract is not good; it requires major changes. Please remove the unnecessary information from the abstract. Add some lines about the presented method, results and how these results solve the particular issue or problem statement.
Introduction: introduction section needs to be improved by including the motivation and how this work is benefits to the actual problem, why there is need of the presented work. Moreover, more SOTA methods should be added in the introduction section and give a comparison with these SOTA methods.
Section 2, Theoretical formulation, this part is written well, but some of the presented formulas are duplicates. Please take more attention to this issue, if you want to use same. A particular citation should be provided for each equation.
In section 3, Fatigue test of high-speed bevel gear in aero-engine, can you provide the actual experimental image, What is the reason behind choosing these mention condition in experimentation? The figure 5 is good, but it could be better.
The optimal parameters used in the geometric model or FEM model of gear mesh should be provided.
How are the results of the proposed model in Tables 6-10 statistically significant?
Author Response
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Reviewer 2 Report
This paper investigated Experimentally and also numerically the dynamical stress in a straight bevel gear. A hard work carried out to prepare these results. There are few points to improve the manuscript:
The results are mainly focused on the temperature variation, I believe that the title of this paper should be modified and add the temperature variation in the title.
The effects of traveling wave resonance are not presented in the paper clearly. The reader expects to see the traveling waves in the manuscript, while the main results are about dynamical stresses due to temperature variations.
Mention in the manuscript that the investigated bevel gear is the straight bevel gear.
There are some minor grammatical mistakes.
Best
Author Response
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Reviewer 3 Report
In this paper, the authors investigated gear traveling wave resonance on fatigue failure of bevel gears. The research is interesting, but it must reach the required scientific level for publishing in the Applied Sciences. The following comments should be addressed in detail if the paper is to be considered for publishing:
1. Referring to Figure 6, the authors should specifically state the terminating condition for stopping the test. Was it a certain sound pressure level, or perhaps when the sound pressure level drastically changed? For example, at approximately 640 seconds, the sound pressure dropped from roughly 150 Pa to 50 Pa. How were the authors sure that no failure occurred here but instead at 934 s?
2. In Section 4.2, FEM constraints should be described in more detail, preferably with some additional images directly from ANYSY.
3. In Figure 6, the authors stated that they chose the 4th ND rotating speed for the test, which is approximately 15 300 RPM (according to Figure 6). This is approximately equal to 255 Hz. However, in Table 3, the authors state that the 4th vibration mode frequency is 12 783 Hz, which corresponds to roughly 766 980 RPM. This should be explained more clearly. Perhaps the results in Table 3 should not be in Hz because Hz is related to seconds, not minutes (10 Hz means 10 rotations in a single second).
Moreover, according to Table 4, the authors state that the test results for the 4th mode are 13 420 Hz. To which test are the authors referring here? Is it the test shown in Figure 6 or some other test? Its parameters should also be mentioned if they are talking about another test.
4. Section 5.1.2. states that the contact stress was verified. However, the authors only concluded that the contact stress obtained by FEM has the same distribution as the one in Ref. [33]. Is the value of 783.77 MPa correct? How was this value verified?
5. Table 13 is, at the very least, questionable. The authors compared stresses at two locations obtained via FEM and concluded that their ratio must be the same in the actual loading conditions, which is not necessarily true. The authors should further justify this. Perhaps the authors should look at the existing standards for bevel gear calculation, such as ISO standards, which can provide formulae for calculating the tooth root stress. If those results agree with FEM results, then at least the authors have two separate confirmations. This is perhaps the most important issue within the manuscript and should be addressed in detail.
6. The authors stated that the gear without defect did not break due to fatigue. How long did the authors conduct the test for such gear before terminating the test? Such gears often fail at high or ultra-high cycle fatigue (often more than a few million cycles).
7. The authors conducted tests for the 4th ND. Did the authors consider conducting tests for 1st or 2nd? Why was the 4th one the only one that was considered?
8. The English language of the entire manuscript could be much better. I suggest that a professional native-speaker editing service edits the entire manuscript.
Author Response
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Round 2
Reviewer 1 Report
All of my concerns have been incorporated. However, I would like to add one more suggestion to the authors. The authors should provide the original citations for the formulas or expressions used in the manuscript.
Author Response
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Reviewer 3 Report
Thank you for revising the paper in light of my feedback. The quality of the paper has now increased.
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