Performance Improvement of Hydrofoil with Biological Characteristics: Tail Fin of a Whale
Round 1
Reviewer 1 Report
CFD numerical modelling of hydrofoil with biological characteristics: tail fin of a whale through simulation to design and optimization. Influence of Re on hydrodynamic performance of hydrofoil was precited using also structural parametric of geometry. The flap angle and flap length was changed. The article is very interesting regarding the issue of fin hydrodynamics. The question and comment about this article are attached below.
- In section 2 Model. How geometry was parametrized. The value (flap angle and length) was changed manually or automatically using script? There is no information about this in section 2 model. What is the other shape optimization method?
- How the geometry change affects the mesh density at the time of changing fin angle and length. Differently, how changing the geometry of the parameters affects the density and numbers of nodes of the numerical grid.
- What is the evolutionary justification for the shape of the fin in relation to, for example: weight of the animal or other parametres. Is it an optimal design in nature? Which way would the fin shape change (the angle fin would increase?)
- Will it change the product used so far after the results of the calculation? Write more information in article to application this product shape optimization.
Author Response
Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The authors presents the Numerical calculations of flow around NACA66 profile and presented it as a Performance improvement of the Hydrofoil with biological characteristics: tail fin of a whale.
Authors described their work correctly but the paper must significantly increase its scientific value before publication.
Paper is written with only some minor errors and inaccuracies.
I would suggest the authors to suitably address the following comments before it can be acceptable for the journal:
Page 3 line 106 There is no "p" symbol in the equations so why it is described in the text?
Page 4 line 127 Why there are no quantitative values comparison between PIV and CFD (for eg. velocity)? In the paper the quantitative values are described for CFD results so only similar vortexes are not enough to validate the model.
Page 6 line 178 It looks awkward when the chapter is opened with the picture.
Page 8 line 214 It looks awkward when the chapter is opened with the picture.
Article main strengths:
1. The authors performed very good numerical calculations
Article main weakness:
1. The paper presents CFD calculations of the flow around NACA66 profile which is, in my opinion, not enough to describe it as a "scientific paper".
2. The conclusions are obvious and there is no clear proposal how to use this results to improve hydrofoil profile to obtain the desired effects.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
Please read carefully the text (especialy this part where You introduce new text in revision) and correct linguistic errors (syntax, missing dots, commas etc.).
