Analytical Model of Gear Thermal Stiffness Based on the Potential Energy Method

Round 1

Reviewer 1 Report

The reference [24] could not be read by the reviewer (it is not an open access type), using it as reference for the actual work, should be done using figures and equations taken from [24] and properly referenced in the text.

More clarity and traceability of the referenced and cited materials is needed: personally, for me, it was hard or impossible to try to find and read articles [17], [24], [31].

1. Line 4 - Indices 1, 2 used for the names are identical;

2.    No names have “*”- corresponding author;

3.      Line 247 – If Fig. 3 is not from a reference (there is no citing) is missing nomenclature for notations r₁, r₂, r_a1, r_a2, r_b1, r_b2;

4.      Line 248 – the notations from Fig. 3, should be placed in text, or below in the figure caption;

5.      In Fig. 4 the graph from the left side shows the variation of K – notation not found anywhere in the text - the graph from the right-side shows K_T variation;

6.      Fig. 4 contains a notation “K-Dai” – It is not clearly presented: “obtained using …”, or presented in [25]. Please point it clearly;

7.      Figure 5 a) and b) sub-captions should be under the Fig 5 caption, and noted in the Figure 5 with a) and b);

8.      As I was not able to identify reference [31] on internet databases, is not clear to me if the nephograph from Fig. 5 is built by the authors using eq. [17], or it is taken from reference [31], should be clarifyed;

9.      In Figure 7 appears again the notation of “K” – not clear the exact meaning of it;

10.  Line 293-294 - As reference literature [24] is not open accessible, I cannot clarify if the stated consistency exists. It would be better to compare a referenced graph from [24], with the actual calculations, and not to state something maybe non-checkable  for any reader (in an open access journal);

11.  Fig 8 – Stiffness K - please clarify;

12.  Line 335-336 – Please reformulate: it is not clear which results are consistent with which research results.

Author Response

  Thank you very much for the valuable comments on the paper named “Analytical Model of Gear Thermal Stiffness based on the Potential Energy Method”. All your comments are very important. They have very important guiding significance to my thesis writing and research work, and these pertinent opinions are the great encouragement and support to me.

Now make the following responses according to your comments, and the corresponding modification is made in the paper. All changes are marked with red font. The response to the reviewer please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

1. Usually tooth surface modifications are introduced in different types of gears, in spur gears, too. Therefore, theoretically point contact occurs between the tooth surfaces. In this study line tooth contact is assumed.
2.  In this study the influence of lubrication and lubricant on mesh stiffness is omitted. The temperature distribution of tooth surfaces depends on the heat generated by the mixed elastohydrodynamic lubrication.
3.  Figure 2: “Hertz contact model of tooth surface contact point” It is only the contact point of tooth profiles. The tooth surfaces are in line contact.
4.  Figure 7: The thermal mesh stiffness for 20 ⁰C to be shown.
5.  Table 3: How are the natural frequencies of the system vibration obtained at different temperatures?
6. What is the ratio of the thermal stiffness and the elastic stiffness?

Author Response

Thank you very much for the valuable comments on the paper named “Analytical Model of Gear Thermal Stiffness based on the Potential Energy Method”. All your comments are very important. They have very important guiding significance to my thesis writing and research work, and these pertinent opinions are the great encouragement and support to me.

Now make the following responses according to your comments, and the corresponding modification is made in the paper. All changes are marked with red font. The response to the reviewer please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

The authors proposed an analytical model to determine the gear thermal stiffness using the potential energy assumption. A comparison with literature data was provided. Overall, the findings presented are acceptable. However, it is suggested that the authors improve the paper further based on the following comments:

Comment #1:

In the abstract, please highlight the accuracy comparison outcome between the proposed model and the ones reported in literature. Is it better? How much better? Why?

Comment #2:

Please elaborate on the heat transfer elements considered in the model. Justify any assumptions made in terms of heat transfer modes considered.

Comment #3:

The contact pressure is computed based on Hertzian theory. How true is this for the whole gear meshing action? How will this affect the accuracy of the model at different meshing conditions? Discuss and elaborate in the manuscript.

Comment #4:

Is the thermal aspect of the lubrication system being considered? This could affect the load carrying ability of the gear contact.

Comment #5:

Please provide a flow chart to summarize the model proposed. 

Comment #6:

Please discuss the impact of being able to accurately determine the gear thermal stiffness towards the application of gear systems. Why is it so critical? Is it even worth doing so.

Author Response

Thank you very much for the valuable comments on the paper named “Analytical Model of Gear Thermal Stiffness based on the Potential Energy Method”. All your comments are very important. They have very important guiding significance to my thesis writing and research work, and these pertinent opinions are the great encouragement and support to me.

Now make the following responses according to your comments, and the corresponding modification is made in the paper. All changes are marked with red font. The response to the reviewer please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Proposed revisions in text:

Line 92 – Figure 1 caption, there seems to be a mistyping: Maybe: “The flow chart to summarize the proposed model”

Line 301 – Figures 8 and 9 are messed up: Figure from line 297 has no caption

Line 297 – refer to fig. 8 – temperatures …

Line 323 there is a Figure caption without a Figure: Figure 9 ….

Please clarify the figures 8,9 references, captions and the content

Line 338 – Table 3: I don’t understand the “time (min) 2nd 4^th ….”. Please clarify

Some issues pointed in previous review are repeating:

Much more clarity and traceability of the referenced and cited materials could be provided: personally, for me, it was hard to try to find articles [17], [24], [31].

1.      Indices 1, 2 used for the names are identical;

2.      Line 342 – Please reformulate: it is not clear which results are consistent with which research results.

Author Response

Thank you very much for the valuable comments on the paper named “Analytical Model of Gear Thermal Stiffness based on the Potential Energy Method”. All your comments are very important. They have very important guiding significance to my thesis writing and research work, and these pertinent opinions are the great encouragement and support to me.

Now make the following responses according to your comments, and the corresponding modification is made in the paper. All changes are marked with red font. The response to the reviewer please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The corrections are accepted.

Author Response

Thank you for your approval ！

Reviewer 3 Report

The authors have responded to the comments in an acceptable manner.

Author Response

Thank you for your approval ！