Mathematical Modeling of the Drug Particles Deposition in the Human Respiratory System—Part 1: Development of Virtual Models of the Upper and Lower Respiratory Tract

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Please read the attached file report.pdf.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Included in the report.

Author Response

Thank you very much for reviewing our manuscript.

Please see the attached file containing answers to your questions and comments.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

In this work, the authors established digital models of human nasal cavity and airways based CT data, and conducted mesh adaption on those two models. Although detailed description is provided on the construction of the virtual respiratory system model, more information is encouraged to be share about the numerical methodology applied in this research work. Please find my comments below.

1. Probably in Ansys 17.0, they had not introduced Fluent Meshing feature for automatic generation of hybrid mesh (Ansys Fluent Mosaic Meshing | CFD Mesh), but in later research work, it is highly recommended to employ the polyhedral or poly-hexcore meshing technique for generating unstructured mesh. In comparison to conventional tetrahedral-dominant mesh, the mosaic mesh can significantly reduce the total number of mesh element while giving accurate simulation results.

2. Is 30 L/min the maximum flow rate to be studied throughout the entire research work? For 30 L/min, there may not be significant turbulence, but transitional flow may occur. What turbulence model was employed in this study? If RANS model was used, what is the y-plus near the wall?

3. How many inflation layers or prism layers were defined near the airway wall to capture the normal gradient?

4. In Part II, will the nasal cavity and bronchopulmonary trunk be integrated to study the particle transport and deposition in the entire geometry?

Author Response

Thank you very much for reviewing our manuscript.

Please see the attached file containing answers to your questions and comments.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Editor,

 

I have carefully reviewed the authors' responses to the concerns I raised in my initial report. The authors have addressed almost all the issues except for points 1 and 8.

 

Regarding point 1, the authors have confirmed in their response that they plan to refer to the present paper as Part 1 of a larger study. If this is their intention and you agree with it, I am willing to accept their decision and retract my objection accordingly.

 

Concerning point 8, the authors have explained in their response why a cell number of 2x10^6 could be considered acceptable for their study. However, the authors have not revised the text to clarify this position for potential readers. Therefore, I must insist that the authors explicitly detail in the text why the mentioned cell number is considered acceptable, especially in light of similar magnitudes referenced in the introduction (citing refs. [34,35] in version 2 of the draft) being described as challenging.

 

I would also like to suggest a few minor corrections to the paragraphs the authors have added in version 2 of the draft.

 

1. Line 102: "to the authors of this paper" -> "to the authors of the present paper"
2. Line 137: "because will only require" -> "because they will only require"
3. Line 325: "For example, for the nasal cavity, sections were created in the OY plane that are shown in green in Figure 12." -> "For example, in the case of the nasal cavity, sections were created in the OY plane, as shown in green in Figure 12.".

 

Comments on the Quality of English Language

Comments are included in the report for the authors.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

All my comments and concerns have been addressed in the revised manuscript. Therefore, the publication of this manuscript is recommended.

Author Response

Please see the attachment.

Author Response File: Author Response.docx