Loss Characterization of a Conventional Variable Inlet Guide Vane^†

Round 1

Reviewer 1 Report

Mandatory Request Changes:Mandatory Changes: Requested changes which are essential for the understanding and completeness of the paper. Paper of author(s) who have not complied with these requests may be rejected.:
From the reviewer’s point of view, there are several definitions and explanations which may confuse readers and can be improved:
• The authors have mentioned an angular deflection ΔΘ in Equation 3 and described it, but this value does not appear in the subsequent analysis and results.

Recommended Requested Changes:Recommended Changes: Changes will improve the quality of the paper. Authors are strongly encouraged to comply with these requests.:
In this part, several recommendations are given which could help the authors improve the quality of this paper:
• In the Nomenclature, ζ is named as “total pressure loss”, this is not accurate, and the reviewer suggests “total pressure loss coefficient”.
• In Figure 1 (b), beside b1, there are also other positions like a1, a2, b2, b3, b4. These positions are not introduced in this paper. If the authors have implemented more tests, it will be interesting to give some descriptions about them.
• The symbol of same parameter may not maintain unitive, e.g. ζc and ζc are both mentioned to represent the so-called “correlation”.
• Some symbols are not mentioned in the Nomenclature or not clearly explained, e.g. t in Figure 5.
• In Figure 6, the point resolution of each picture seems not the same. Are the measurement configurations for each case different?

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Mandatory Request Changes:Mandatory Changes: Requested changes which are essential for the understanding and completeness of the paper. Paper of author(s) who have not complied with these requests may be rejected.:
Good and interesting article describing IGV behaviour. There are some changes suggested:
- Give the definition of relative radius
- Nomenclature add t which is used in Figure 5.
- Measurement devices and their uncertainty should be described more in detail
- Add figure illustrating stagger angle, circumferential angle etc.
- Explain more in detail fig 3b.

Recommended Requested Changes:Recommended Changes: Changes will improve the quality of the paper. Authors are strongly encouraged to comply with these requests.:
- Using “cf.” is not common practice and could be avoided
- One could add beta_2 in fig 4. for clarification
- Values of Theta_off could be given
- On page 8 second last sentence, the location (r) of could be given
- On page 9, there is good discussion of overturning of circumferential velocity. Figure illustrating the flow field could be added

Author Response

Please kindly see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Mandatory Request Changes:Mandatory Changes: Requested changes which are essential for the understanding and completeness of the paper. Paper of author(s) who have not complied with these requests may be rejected.:
When referring to vIGV setting angle the frame of reference should be added for easier understanding (angle wrt. axial/radial or circumferential)

Recommended Requested Changes:Recommended Changes: Changes will improve the quality of the paper. Authors are strongly encouraged to comply with these requests.:
The motivation for the stream line correlation approach should be better explained. Initially, I thought the passage will discuss a representative approach of inlet dynamic pressure calculation q under consideration of inhomogeneities.
Furthermore, it should be stated that the procedure has to be repeated for other inlet piping configurations.
Some minor spelling issues.

Author Response

Please kindly see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The paper is well written and clear. It provides an interesting insight into the losses in IGVs. The minor comments from the first review round (conference publication) have been addressed. 

Reviewer 2 Report

The authors are addressed all previous comments and suggestions. The readability of the article has improved and it can be accepted for publication.