Review of Film Cooling Techniques for Aerospace Vehicles
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThis article is a review of thin film cooling technology for aerospace vehicles. Thin film cooling is an important method for controlling the surface temperature of high-temperature components, which improves efficiency through innovative technological advancements.
Below are comments:
This review is a very long article. Now let’s look at the tittle and subtittles:
Line 33, introduction.
Line 169, the sub section tittle is 1.1. Advances in Gaseous Film Cooling Research.
Line 389, the sub section tittle is 1.1. Advances in Liquid Film Cooling Research.
Line 665, the sub section tittle is 1.1. Validation of Coolant Injector Hole Configuration
Line 728, the sub section tittle is 1.1. Advanced materials for turbine blade design
(All those sub tittle are wrong, they are all 1.1)
Line 758, the tittle is 1. Recent Progress and Innovations in Film Cooling Technology
Line 776, the sub section tittle is 1.1. Cooling Slot Flow Dynamics
Line 876, the sub section tittle is 1.2. Determinants of Film Cooling Effectiveness
Line 1406, the sub section tittle is 1.4. Computational Fluid Dynamics (CFD) for Film Cooling
(Those tittle should be numbered as section 2, 2.1, 2.2 and 2.3, besides, no 1.3 right now)
Line 1489, the tittle is 2. Film Cooling for Combustion chamber
Line 1498, the sub section tittle is 2.1. Studies on Combustion Chamber Film Cooling
Line 1625, the sub section tittle is 2.2. Innovations in Combustion Chamber Film Cooling
(Those tittle should be numbered as section 3)
Line 1722, the tittle is 3. Film Cooling for Gas Turbine Blades
Line 1736, the sub section tittle is 3.1. Studies on Turbine Blades Film Cooling
Line 1848, the sub section tittle is 3.2. Mechanism of Vortices
Line 1889, the sub section tittle is 3.3. Innovations in Gas Turbine Blade Film Cooling
Line 1960, the sub section tittle is 3.4. Effects of Flow Control Parameters on Cooling Effectiveness
(Those tittle should be numbered as section 4)
Line 2131, the tittle is 4. Film Cooling for Hypersonic Vehicles
Line 2143, the sub section tittle is 4.1. Studies on Hypersonic Film Cooling
Line 2266, the sub section tittle is 4.2. Innovations in Hypersonic Film Cooling
Line 2318, the sub section tittle is 4.3. Development of transpiration coolant materials
Line 2393, the sub section tittle is 4.4. Transpiration cooling techniques for hypersonic applications
(Those tittle should be numbered as section 5)
Finally, line 2439, 5. Perspectives on Future Film Cooling Research
What is number 9 when started the problems in line 691?
Should be numbered as 1.
From my opinion, the logic and link between each section is not very clear.
The current section 3 Film Cooling for Gas Turbine Blades is much well written than the other sections. The figures are good to show the results.
However, those results are not presented in the other sections for example, Recent Progress and Innovations in Film Cooling Technology, Film Cooling for Combustion chamber.
Besides, the Advanced materials for turbine blade design part can be deleted.
Meanwhile, the authors should focused more on a simple topic.
Author Response
Response to the First Reviewer
The authors appreciate the reviewer and address the comments point by point as follows.
- This article is a review of thin film cooling technology for aerospace vehicles. Thin film cooling is an important method for controlling the surface temperature of high-temperature components, which improves efficiency through innovative technological advancements. Below are comments:
This review is a very long article. Now let’s look at the title and subtitles:
Line 33, introduction.
Line 169, the sub section tittle is 1.1. Advances in Gaseous Film Cooling Research.
Line 389, the sub section tittle is 1.1. Advances in Liquid Film Cooling Research.
Line 665, the sub section tittle is 1.1. Validation of Coolant Injector Hole Configuration
Line 728, the sub section tittle is 1.1. Advanced materials for turbine blade design
(All those sub tittle are wrong, they are all 1.1)
Response:
The title “Introduction” is now Section 1 (Line 38)
New sub-sections include:
1.1 Advances in Gaseous Film Cooling Research (Line 140)
1.2 Advances in Liquid Film Cooling Research (Line 344)
1.3 Other Film Cooling Techniques for Aerospace Components (Line 457)
1.4 Validation of Coolant Injector Hole Configuration (Line 504)
- Line 758, the tittle is 1. Recent Progress and Innovations in Film Cooling Technology
Line 776, the sub section tittle is 1.1. Cooling Slot Flow Dynamics
Line 876, the sub section tittle is 1.2. Determinants of Film Cooling Effectiveness
Line 1406, the sub section tittle is 1.4. Computational Fluid Dynamics (CFD) for Film Cooling
(Those tittle should be numbered as section 2, 2.1, 2.2 and 2.3, besides, no 1.3 right now)
Response:
The title “Recent Progress and Innovations in Film Cooling Technology” is now Section 2 (Line 566)
New sub-sections include:
2.1 Cooling Slot Flow Dynamics (Line 583)
2.2 Determinants of Film Cooling Effectiveness (Line 679)
2.3 Current trends and developments in Film Cooling (Line 774)
2.4 Computational Fluid Dynamics (CFD) for Film Cooling (Line 1206)
- Line 1489, the tittle is 2. Film Cooling for Combustion chamber
Line 1498, the sub section tittle is 2.1. Studies on Combustion Chamber Film Cooling
Line 1625, the sub section tittle is 2.2. Innovations in Combustion Chamber Film Cooling
(Those tittle should be numbered as section 3)
Response:
The title “Film Cooling for Combustion Chamber” is now Section 3 (Line 1269)
New sub-sections include:
3.1 Studies on Combustion Chamber Film Cooling (Line 1279)
3.2 Innovations in Combustion Chamber Film Cooling (Line 1407)
- Line 1722, the tittle is 3. Film Cooling for Gas Turbine Blades
Line 1736, the sub section tittle is 3.1. Studies on Turbine Blades Film Cooling
Line 1848, the sub section tittle is 3.2. Mechanism of Vortices
Line 1889, the sub section tittle is 3.3. Innovations in Gas Turbine Blade Film Cooling
Line 1960, the sub section tittle is 3.4. Effects of Flow Control Parameters on Cooling Effectiveness
(Those tittle should be numbered as section 4)
Response:
The title “Film Cooling for Gas Turbine Blades” is now Section 4 (Line 1457)
New sub-sections include:
4.1 Studies on Turbine Blades Film Cooling (Line 1472)
4.2 Mechanism of Vortices (Line 1583)
4.3 Innovations in Gas Turbine Blade Film Cooling (Line 1611)
4.4 Effects of Flow Control Parameters on Cooling Effectiveness (Line 1681)
- Line 2131, the tittle is 4. Film Cooling for Hypersonic Vehicles
Line 2143, the sub section tittle is 4.1. Studies on Hypersonic Film Cooling
Line 2266, the sub section tittle is 4.2. Innovations in Hypersonic Film Cooling
Line 2318, the sub section tittle is 4.3. Development of transpiration coolant materials
Line 2393, the sub section tittle is 4.4. Transpiration cooling techniques for hypersonic applications
(Those tittle should be numbered as section 5)
Response:
The title “Film Cooling for Hypersonic Vehicles” is now Section 5 (Line 1825)
New sub-sections include:
5.1 Studies on Hypersonic Film Cooling (Line 1850)
5.2 Innovations in Hypersonic Film Cooling (Line 1966)
5.3 Development of transpiration coolant materials (Line 1983)
5.4 Transpiration cooling techniques for hypersonic applications (Line 2056)
- Finally, line 2439, 5. Perspectives on Future Film Cooling Research.
Response: The title “Perspectives on Future Film Cooling Research” is now Section 6 (Line 2101).
- What is number 9 when started the problems in line 691? Should be numbered as 1.
Response: In the revised manuscript, the number ‘9’ has been numbered as ‘1’ (Line 530).
- From my opinion, the logic and link between each section is not very clear.
The current section 3 Film Cooling for Gas Turbine Blades is much well written than the other sections. The figures are good to show the results.
However, those results are not presented in the other sections for example, Recent Progress and Innovations in Film Cooling Technology, Film Cooling for Combustion chamber.
Response: Figures 3 and 4 are provided in Sub-section 2.2, while Figures 6 and 7 (Sub-section 3.2) visually summarize key results for improved interpretation.
- Besides, the Advanced materials for turbine blade design part can be deleted.
Response: Following the recommendation to delete the sub-section “Advanced materials for turbine blade design,” previously named 1.5. under Introduction (Line 728). The sub-section has been deleted.
- Meanwhile, the authors should focused more on a simple topic.
Response: We streamlined the review by removing insignificant sub-sections, narrowing its focus to a more precise topic.
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsDear Authors,
Kindly address the comments.
Thanks
Comments for author File: Comments.pdf
The quality of English needs improvement, and the article lacks a scientific tone. Please revise accordingly.
Author Response
Response to the Second Reviewer
The authors appreciate the reviewer and address the comments point by point as follows.
- Comments on the Quality of the English Language: The quality of English needs improvement, and the article lacks a scientific tone. Please revise accordingly.
Response: The article has been revised per your recommendations, resulting in refined language and a more scientific tone.
- Table 1 is not properly aligned. All tables throughout the article should be consistently and clearly formatted.
Response: Tables 1-12 have been properly and consistently formatted.
- In Line 208, the phrase “In another experimental study” requires an appropriate reference. Additionally, several other places throughout the manuscript lack proper citations. Authors should ensure that all claims are properly referenced.
Response:
The phrase ‘In another experimental study’ (line 208) and several other places in the manuscript (lines 177 - 180) have been cited correctly.
“In another experimental study coupled with a theoretical investigation, a convergent-divergent nozzle was employed to study the heat transfer effects, the role of the nozzle throat in cooling film stability, and the appropriate methods for effectively analyzing the impacts of boundary and mixing layers [22].”
- On Page 7, one of the paragraphs is overly lengthy and extends beyond a single page. The authors should consider breaking it down for better readability.
Response: The paragraph on page 7 has been broken down for better readability.
- In Section 1, the scope of the paper is summarized twice—first in Line 255 and again in Line 379. This repetition should be avoided. The authors may consolidate or reiterate the scope more concisely.
Response: In Section 1, lines 255 à 223 describe one of the unsolved problems and research gaps in gaseous film cooling technique, while lines 379 à 334 summarize advances in gaseous film cooling research.
- The subsection "1.1" appears twice, with the second occurrence at Line 615. Please correct the section numbering to avoid confusion.
Response: The sub-section numbering 1.1. has been corrected.
- Figures 1 and 2 are placed side by side. To maintain clarity, the authors could consider combining them as a single figure with sub-parts (e.g., Figure 1A and Figure 1B), or separate them with clear individual labels.
Response: Figures 1 and 2 have been separated with clear individual labels.
- The nomenclature section appears abruptly at Line 756. Please review its placement and ensure it is introduced appropriately within the structure of the manuscript.
Response: The nomenclature section has been placed before the introduction/main text as a separate subsection.
- While the authors discuss geometric impact design, the manuscript lacks sufficient pictorial representations or visual data from relevant studies to support the discussion. Including such figures would enhance the clarity and depth of the analysis.
Response:
Figures 3 and 4 have been added to Sub-section 2.2 (‘Determinants of Film Cooling Effectiveness’), and Figures 6 and 7 have been included in Sub-section 3.2 (‘Innovations in Combustion Chamber Film Cooling’) to enhance the analytical clarity and depth.
- Although the authors attempt to present the content in chronological order, it remains unclear due to missing references. Ensure that historical development is properly supported with citations.
Response:
Historical developments have been adequately supported with citations throughout the manuscript.
- The manuscript lacks clarity in how experimental details and numerical developments are presented. These two aspects should be structured separately to improve coherence.
Response: We detail the experimental and numerical developments in separate paragraphs and structure them in dedicated tables to ensure coherence in their respective sections.
- The manuscript suffers from structural and writing issues. The flow of the article is disjointed, and the key messages are not effectively communicated. It appears to include several inferences from other works without sufficient synthesis or logical connection. Substantial improvement is needed in writing quality and overall organization.
Response: The manuscript is now well-structured, with improved clarity and logical coherence. All writing issues have been resolved, ensuring a smooth flow and effective communication of key messages.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThis article presents the basics of film cooling, its applications and technical features. The authors cover innovations in combustion chambers, gas turbine blades and hypersonic vehicles. The article is voluminous, from a number of great studies, contributes to science. Given that film cooling is not only used in aircraft but also in cooling devices such as cooling towers and distillation column, etc., it is interesting to compare the methods used in aerospace vehicles. There are several questions for the authors:
- Figure 4 shows the vortex structures resulting from the interaction between the transverse flow of the jet and the experimentally observed properties of film cooling. What research has been done on the problem of non-uniformity of water or air flows in film cooling? Can flow non-uniformities be evaluated as one of the factors affecting the efficiency of film cooling?
- In the material development section for evaporative coolants, research on the evaporation process is mentioned. What is the status of the mathematical description of droplet detachment in the film cooling process? How far have we gotten and what issues are worth exploring?
- It is recommended that authors accompany each section with a summarizing table to quickly evaluate the outcome of each section. This will help to study the material more easily.
- Usually an article (including a review article) is meant to be a squeeze article and should only capture the essence of the research. Here the authors have done a lot of work, but was it worth the effort? In our opinion, this volume of the article complicates the task of mastering this material and, as it usually happens, the material is put into a “long box”. For this kind of voluminous materials there is another type of scientific publication and it is a monograph.
Author Response
Response to the Third Reviewer
The authors appreciate the reviewer and address the comments point by point as follows.
“This article presents the basics of film cooling, its applications and technical features. The authors cover innovations in combustion chambers, gas turbine blades and hypersonic vehicles. The article is voluminous, from a number of great studies, contributes to science. Given that film cooling is not only used in aircraft but also in cooling devices such as cooling towers and distillation column, etc., it is interesting to compare the methods used in aerospace vehicles. There are several questions for the authors:”
- Figure 4 shows the vortex structures resulting from the interaction between the transverse flow of the jet and the experimentally observed properties of film cooling. What research has been done on the problem of non-uniformity of water or air flows in film cooling? Can flow non-uniformities be evaluated as one of the factors affecting the efficiency of film cooling?
Response:
In the revised manuscript, Figure 4 is now Figure 8.
Part 1:
The non-uniform distribution of water or air flows in film cooling has been widely researched because it significantly influences cooling effectiveness, thermal protection, and aerodynamic behavior in gas turbines, jet engines, and various industrial applications.
The key research areas and findings are summarized below:
- Causes of Non-Uniform Flow in Film Cooling Applications
- Hole Design and Spacing: Experiments demonstrate that inconsistent cooling stems from variations in hole design, such as cylindrical, fan-shaped, or laid-back structures, including their spatial density (closely packed or widely spaced patterns)
- Turbulence and Mainstream Interactions: Turbulent freestream conditions degrade coolant jet uniformity and coverage effectiveness
- Ratio of Coolant Jet Momentum to Freestream Momentum (I): Insufficient momentum ratios induce jet lift-off, while elevated ratios promote pronounced penetration, generating uneven cooling distribution
- Effects of Non-Uniform Cooling
- Thermal Inhomogeneities and Localized Overheating Zones: Irregular flow distribution causes localized thermal peaks, accelerating component degradation.
- Aerodynamic Losses: Unsteady coolant injection increases mixing losses, degrading turbine efficiency.
- Control Methodologies
- Advanced Hole Designs: Diffuser and fan-shaped hole geometries enhance lateral coolant dispersion and distribution uniformity
- Techniques for Regulating Flow: These techniques include pulsed jets, vortex generators, and micro-vanes, all of which help stabilize coolant flow
- Additive Manufacturing (AM): Cooling channels fabricated via additive manufacturing allow intricate designs (such as lattice structures) to achieve consistent flow distribution.
- Experimental and Numerical Methods
- Experimental: Experimental studies employ Pressure-Sensitive Paint (PSP) and infrared (IR) thermography to assess cooling effectiveness, whereas Particle Image Velocimetry (PIV) measures flow non-uniformity.
- Computational Fluid Dynamics (CFD): Large Eddy Simulation (LES) and RANS turbulence models are employed in CFD to evaluate flow non-uniformity patterns.
Key References
[5] Bogard, D.G.; Thole, K.A. (2006). Gas Turbine Film Cooling. Journal of Propulsion and Power, 22(2), 249–270.
[136] Haven, B.A.; Kurosaka, M. Kidney and anti-kidney vortices in crossflow jets. Journal of Fluid Mechanics, 1997, 352, pp. 27–64.
[159] Goldstein, R.J.; Eckert, E.R.G.; Burggraf, F. Effects of Hole Geometry and Density on Three-Dimensional Film Cooling. International Journal of Heat and Mass Transfer, 1974, 17(5), 595–607. https://doi.org/10.1016/0017-9310(74)90007-6.
[162] Pietrzyk, J.R.; Bogard, D.G.; Crawford, M.E. Effect of Density Ratio on the Hydrodynamics of Film Cooling. Journal of Turbomachinery, 1990, 112(3): 437–443. https://doi.org/10.1115/1.2927678.
[174] Barigozzi, G.; Franchini, G.; Perdichizzi, A. The effect of an upstream ramp on cylindrical and fan-shaped hole film cooling: Part I—Aerodynamic results. Proceedings of GT2007, ASME Turbo Expo: Power for Land, Sea and Air, Montreal, Canada, 14–17 May 2007. Paper No: GT2007-27077, Volume 4, pp. 105–113. https://doi.org/10.1115/GT2007-27077.
[175] Barigozzi, G.; Franchini, G.; Perdichizzi, A. The effect of an upstream ramp on cylindrical and fan-shaped hole film cooling: Part II—Adiabatic effectiveness results. Proceedings of GT2007, ASME Turbo Expo: Power for Land, Sea and Air, Montreal, Canada, 14–17 May 2007. Paper No: GT2007-27079, Volume 4, pp. 115-123; https://doi.org/10.1115/GT2007-27079.
Part 2:
Both experimental and computational research have thoroughly established that flow non-uniformities critically influence film cooling performance.
Below is an analysis of how non-uniformities affect cooling performance and their evaluation methods.
- The Impact of Flow Non-Uniformities on Film Cooling Performance
- Insufficient Thermal Protection: Uneven coolant distribution causes localized overheating (hot spots) and thermal streaks, which degrade blade durability. For example, when coolant jets detach or distribute non-uniformly, downstream areas experience insufficient thermal protection.
- Compromised Aerodynamic Performance: Asymmetric or unsteady coolant injection perturbs boundary layer development, elevating mixing losses and degrading turbine performance.
- Reduced Film Cooling Effectiveness (η): Spatial non-uniformities in the flow field produce localized variations in cooling effectiveness (η).
- Techniques for Assessing Flow Irregularities
- Experimental Methods
- Infrared (IR) Thermal Imaging: Visualizes surface temperature distribution to detect cooling irregularities.
- Pressure-Sensitive Paint (PSP): Identifies coolant distribution patterns and locates regions of diminished thermal protection.
- Particle Image Velocimetry (PIV): Measures velocity variance and quantifies flow separation phenomena.
- Numerical Approaches
- Computational Fluid Dynamics Modeling (RANS/LES Approaches): Evaluates flow non-uniformity impacts through turbulence modeling, including SST k-ω for jet interaction analysis.
- Thermal Protection Effectiveness (η) Distribution Maps: Identifies zones of insufficient coolant coverage.
- Major Discoveries
- Film Hole Arrangement and Spacing Parameters: Diffusion-shaped orifices (e.g., fan-shaped and laid-back designs) mitigate flow non-uniformities through enhanced lateral coolant dispersion.
- Coolant-to-Mainstream Momentum Ratio (I).
- Turbulence Influence: Elevated freestream turbulence levels (exceeding 10%) adversely affect jet coherence and distribution uniformity.
- Control Methodologies
- Flow Control Devices
- Additive Manufacturing
Key References
[5] Bogard, D.G.; Thole, K.A. (2006). Gas Turbine Film Cooling. Journal of Propulsion and Power, 22(2), 249–270.
[65] Bohn, D.; Ren, J.; Kusterer, K. Conjugate heat transfer analysis for film cooling configurations with different hole geometries. Volume 5: Turbo Expo 2003, Parts A and B. https://doi.org/10.1115/GT2003-38369.
[159] Goldstein, R.J.; Eckert, E.R.G.; Burggraf, F. Effects of Hole Geometry and Density on Three-Dimensional Film Cooling. International Journal of Heat and Mass Transfer, 1974, 17(5), 595–607. https://doi.org/10.1016/0017-9310(74)90007-6.
[162] Pietrzyk, J.R.; Bogard, D.G.; Crawford, M.E. Effect of Density Ratio on the Hydrodynamics of Film Cooling. Journal of Turbomachinery, 1990, 112(3): 437–443. https://doi.org/10.1115/1.2927678.
- In the material development section for evaporative coolants, research on the evaporation process is mentioned. What is the status of the mathematical description of droplet detachment in the film cooling process? How far have we gotten, and what issues are worth exploring?
Response:
Accurately predicting droplet separation in film cooling is nontrivial, particularly in aero engines and turbines where liquid coolants (e.g., water droplets) or condensate are present—an active research frontier.
Below is a detailed assessment of the current status, key challenges, and future research directions:
- State-of-the-Art in Mathematical Modeling
- a) Governing Equations and Physics
Droplet detachment:
- Viscous shear-induced forces – the primary flow field induces droplet ejection via surface shear forces.
- Capillary force phenomena – contact angle hysteresis, wettability.
- Thermophoresis and vaporization – heat transfer alters droplet stability.
Key Models Used:
- Force Balance Models
- Phase-Field and Volume-of-Fluid (VOF) Methods
- Empirical Correlations
- b) Experimental Validation
- i) High-speed imaging – quantifies detachment dynamics.
- ii) Interferometry – measures thin-film breakup before droplet formation.
- Key Challenges and Research Gaps
- a) Multiphysics Coupling Challenges: Integrated modeling of liquid-film fragmentation, droplet dispersion, and phase-change phenomena lacks universal models.
- b) Surface Roughness and Wettability: Real turbine blades have microstructures that alter contact angles unpredictably.
- c) Turbulent Flow Field Interactions: High Reynolds number flows generate stochastic droplet dispersion patterns, necessitating scale-resolving simulations (LES/DNS) despite their significant computational cost.
- d) Scalability: Laboratory-scale investigations at low Weber numbers often fail to replicate actual engine operating environments.
- Promising Research Directions
- Hybrid Modeling: Combine VOF with Lagrangian particle tracking (LPT) for detached droplets.
- Machine Learning: Develop reduced-order models using high-resolution CFD and experimental datasets to forecast droplet detachment behavior.
- Advanced Surface Coatings: Engineered surface coatings with extreme wettability (superhydrophobic/hydrophilic) require dynamic contact angle modeling for precise detachment control.
- Transient Simulations: High-resolution DNS of film rupture under shear.
- Recent Advances
- Droplet Detachment in Mist Cooling: The shear-induced mist detachment mechanism was simulated via coupled Volume-of-Fluid and Lagrangian Particle Tracking methods.
- Ice/Slag Detachment in Cold Conditions: The additive effects of phase-change phenomena (e.g., droplet freezing) necessitate novel thermo-mechanical criteria.
Key Reference
Wörner, M. Numerical modeling of multiphase flows in microfluidics and micro process engineering: a review of methods and applications. Microfluidics and Nanofluidics, 2012, 12(6), 841–886. doi:10.1007/s10404-012-0940-8.
- It is recommended that authors accompany each section with a summarizing table to quickly evaluate the outcome of each section. This will help to study the material more easily.
Response: Each section of the manuscript includes a summarizing table to facilitate quick evaluation of key outcomes and improve readability.
- Usually an article (including a review article) is meant to be a squeeze article and should only capture the essence of the research. Here the authors have done a lot of work, but was it worth the effort? In our opinion, this volume of the article complicates the task of mastering this material and, as it usually happens, the material is put into a “long box”. For this kind of voluminous materials there is another type of scientific publication, and it is a monograph.
Response:
In this review, the authors prioritize thoroughness to address gaps in a complex field while maintaining a structured and readable format without compromising rigor. Future efforts could enhance accessibility by splitting content into focused topical reviews or adding a “Quick Guide” summary.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsDear Author's.
Thanks for addressing the comments.
Minor English language corrections and typos to be rechecked.
Author Response
The authors appreciate the reviewer and address the comments point by point as follows.
- “Minor English language corrections and typos to be rechecked.”
Response: The recommended English language corrections have been implemented, and typos have been carefully rechecked, significantly improving the manuscript’s clarity.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authorsrecommended for publication.
Author Response
The authors appreciate the reviewer and address the comments point by point as follows.
- “Comments and Suggestions for Authors: recommended for publication.”
Response: We thank the reviewer for their positive evaluation and recommendation for publication. The manuscript has been revised and finalized accordingly.
Author Response File: Author Response.pdf