A Numerical Study of the Sealing and Interstage Pressure Drop Characteristics of a Four-Tooth Three-Stage Brush Combination Seal

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Major Comments
1. The abstract is difficult to follow due to excessive sentence length and nested ideas. Breaking it into shorter sentences would improve readability.

2. The terms "entropy increase" and "damping dissipation" are mentioned without a clear explanation of their role in interstage pressure drop imbalance. Although a thermodynamic formula for evaluating entropy generation is provided in the text, further clarification is needed.

3. The literature review in the introduction appears somewhat lacking. The reviewer recommends that the authors identify and organize at least ten relevant papers published within the past five years.

4. The authors used the k-ω SST model, but it is necessary to confirm whether the laminarization phenomenon in the gap or porous region is properly reflected.

5. Why do velocity vectors appear to bounce randomly in various directions at the seal exit in Figure 10? This behavior suggests grid insufficiency or poor convergence.

6. Section 4 remains vague and superficial. For each case, entropy generation should be quantitatively obtained and compared, and its contribution should be precisely analyzed.

7. Is the geometry presented in this paper optimal? The reviewer recommends that the authors analyze it using optimization tools or similar methods.

8. The conclusion states that pressure drop balancing comes at the cost of a small increase in leakage rate, but it does not elaborate on whether this trade-off is acceptable for real-world applications. A brief discussion on its practical relevance would be beneficial.

Minor Comments
1. "Megaparsec" is likely a typographical error; it should be "megapascal."

2. For clarity, please provide a more detailed caption for Figure 13. Alternatively, label the subfigures (e.g., a, b, c, and d) and explain the numbers beneath them.

3. Some phrases are unclear or redundant. For example:

"The structural parameters of the combined seal were improved based on the methods of ‘axial dimension’ cross-compensation of ‘radial dimension’ and ‘non-gradient setting of parameters at all stages.’"
→ This phrase is unclear and should be rewritten for better readability.
"The brush bundle effectively achieves the irreversible dissipation of the energy of the high-speed fluid, to achieve sealing under the rotating working conditions."
→ This sentence is somewhat repetitive and could be more concise.

Comments on the Quality of English Language

Many sentences are long and difficult to follow. Breaking them into shorter, more structured statements would improve readability.

Author Response

Dear reviewer:
We hope this message finds you well!
The revision of our paper (Manuscript ID: applsci-3475296) has been completed, and we are now submitting the revision instructions to you.
(For details, please refer to the document ‘Response Letter-2025.03.04’)

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The English language is fine and does not require improvement.

Comments for author File: Comments.pdf

Author Response

Dear reviewer:
We hope this message finds you well!
The revision of our paper (Manuscript ID: applsci-3475296) has been completed, and we are now submitting the revision instructions to you.
(For details, please refer to the document ‘Response Letter-2025.03.04’)

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have addressed the reviewers' requests to some extent and revised the manuscript. However, it still appears somewhat lengthy. It is recommended to streamline the content for better organization and conciseness.

Comments on the Quality of English Language

Some parts of your sentence sound a bit awkward. I suggest seeking professional help.

Author Response

Dear reviewer:
We hope this message finds you well!
The revision of our paper (Manuscript ID: applsci-3475296) has been completed, and we are now submitting the revision instructions to you.
(For details, please refer to the document ‘Response Letter-2025.03.12’)

Author Response File: Author Response.docx