An Investigation on Optimized Performance of Voluteless Centrifugal Fans by a Class and Shape Transformation Function
Round 1
Reviewer 1 Report
The article presents efficiency tests of centrifugal fans without a spiral using the developed function of classification and shape transformation based on the shape of fan blades and lobes. A multi-criteria optimization approach based on the Kriging method was proposed to increase fan efficiency and static pressure, followed by numerical simulations of specific fans. The analysis focused on energy loss using the dissipation function. Dissipation function analysis helped determine the location of energy losses in the internal flow of the fan, and successful validation was achieved by comparison with pressure contours and current distribution.
List of mistakes:
The main problem in the article is the poor quality of the drawings. In most cases, they have low resolution, which makes their readability low and makes it difficult to read the article. This is especially visible in the figures showing the results of the simulation.
Conclusions
After careful consideration, the article presents substantive values and thus, after making the necessary corrections, meets the high requirements of the journal.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments on the paper are given as follows:
1- It is suggested to amend a section as the numerical analysis to discuss more on the reported results. In this way, the paper's founding could be sufficient for an original research paper.
2- Which type of boundary condition is employed in FE simulation? Please make clear the BC and the basic assumption about this subject.
3- In my view, Kriging is a well-known optimization algorithm, and describing how it works is unnecessary. Revise section 2.2.
4- What are the advantages and disadvantages of the current theory compared to other theories? Authors are invited to comment on this situation.
5- What are the major limitations of the Kriging model?
6- The error percentages are obtained in a reasonable range, however, in some cases, the model could not adequately estimate the experimental value.
7- The paper has been prepared as a technical report. Additionally, it needs more scientific investigation on the reported results. Authors are invited to extend the paper results and avoid only reporting the test results.
Minor editing of English language required
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
The manuscript needs revision before considering for possible publication in this journal of high repute. Some of the major points are as follows:
1. The abstract needs to be rewritten.
2. The quality of English is very poor to be considered for publication.
3. Authors must add some recent publications related to the topic.
4. Why Kriging was used instead of coKriging? Authors are advised to compare the two.
5. Conclusion section must be rewritten up to the point.
The quality of the English language needs to be revised throughout the manuscript. The English quality is extremely poor.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
No comment
No comment
Reviewer 3 Report
The manuscript is suitably modified by the authors and may be considered for publication.
