Round 1

Reviewer 1 Report

Comments (Major revision)

This paper adapts a quasi-steady model previously proposed for flat plate falling problems to describe the freely falling motion of the wing. Additionally, CFD simulations are used to analyze the wing's free fall movement with varying parameters and assess the quasi-steady model's performance. The study finds that the falling wing's motion characteristics are mainly observed in the longitudinal plane, and the modified quasi-steady analytical model can accurately describe the free fall dynamics to a certain extent.

This work has the potential for publication, but it cannot be accepted in its current form. Please take into account all the attached comments and best of luck.

1.      Please enrich the abstract and conclusion with numerical results from your theoretical study, CFD modeling, and experimental work.

2.      You can include up to 6 keywords; don't limit yourself to just three keywords.

3.      Please add a reference for this statement: "As early as 1854, Maxwell studied the irregular tumbling phenomenon of thin plates."

4.      Please correct "witch" on line 117.

5.      Please include the unit of I in the title of Fig. 6.

6.      Unit of I in Fig. 7 is missing. Figs. 9, 10, and 11 too!

7.      Please use symbols for figures 9 and 11.

8.      The idea your paper addresses is original, but I think the structure you have established for your manuscript is difficult to grasp at first glance. I don't see the usefulness of CFD modeling in your work. It is not detailed and addressed according to standards. You have not mentioned the boundary conditions for CFD modeling, the specifications of the boundary layer used, y+ value, convergence criteria for your turbulence model, numerical schemes for pressure-velocity coupling, discretization of pressure gradients, k and omega. If you have used the 6DOF solver, you should mention it. Which CFD software did you use? Fluent, Comsol, Star CCM+, CFX? What is the time step value you used? You must outline all the assumptions you have made for CFD calculations because the physical phenomenon you are dealing with is 3D.

9.      You need to present the equation for the W-criterion quantity and justify its use and importance. What is its strength compared to the vorticity field, Q-criterion, turbulent kinetic energy dissipation, etc.?

10.  The revised version of your paper must contain all the essential information for CFD modeling to ensure the reproducibility of your numerical study. Otherwise, you must remove it from the revised version of your paper.

11.  Please provide a summary and group the equation of your theoretical model on which you have applied the Range-Kutta method. You can use an Appendix section to present the integral calculation since these elementary calculations clutter the presentation of your paper.

12.  Please create a "Results and Discussion" section in which you will present in three parts: Results and Discussion.

a)      Quasi-steady analytical model

                                i.            Effect of MOI

                              ii.            Effect of COM position on freely falling wing

b)      Experiment results

                            iii.            Effect of MOI

                            iv.            Effect of COM position on freely falling wing

c)      Comparison between the Quasi-steady analytical model and experimental results

 

 

Moderate editing of the English language

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Dear Authors, 

first of all I would like to thank you for the opportunity to read your interesting manuscript. 
I would like to suggest to correct the following details:

*  CFD explanation of aberration in the name when is first use

* line 102 add a, b in the plot 

* line 177 "In order to easily change the MOI of the wing about Y′ axis, ", I didn't find what you mean by Y′ axis, apart of "MOI about the Y′-axis witch is vertical to X′OZ′ plane,". I suggest try to put all this information in the plot. 

* figure 6, could you add more explanation, why for some time values, CFD model describe data worse then analytical model, and in some CFD and analytical are very similar and shifted according to experimental data. 

* line 225 - "while maintaining the mass and shape of the wing remains unchanged", what influence the interia momenta? 

One more question did you think about analysis of uncertainties: statistical and systematical?

Best regards. 

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The corrected version of the article takes into consideration all the remarks that I had addressed. It is for this reason that I believe that the article titled “Investigation on the free fall dynamic behavior of rectangular wing with variable center of mass location and variable moment of inertia” and referenced “aerospace-2369635” is acceptable for publication in the “ Aerospace” journal.