Reducing the Cooling Energy Demand by Optimizing the Airflow Distribution in a Ventilated Roof: Numerical Study for an Existing Residential Building and Applicability Map

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors,

I have reviewed your submitted paper, and while I find it interesting, I believe substantial revisions and additions are necessary. Below, I have summarised my main comments:

1.      I initially checked the submitted paper using TURNITIN software to identify potentially problematic sections for similarity. The software indicated a 35% similarity index. Similarities were found throughout the text, so I recommend a thorough review by a language editor. The most problematic section is 2.3, which I suggest rewriting entirely, as the software flagged almost the entire section as non-original work.

2.      The authors do not follow the journal's editorial guidelines.

3.      Figures 3, 9, and 14 are of poor quality.

4.      The Nomenclature section is missing.

5.      The unit of power is watt, denoted as [W] in honour of James Watt, not [w]. (e.g., Figures 3, 4)

6.      Why is the temperature in Figure 8 given in [K]? Using [°C] would make the figure easier to interpret.

7.      Lines 144-146: On what basis do you assume that the total heat transfer coefficient is equal to or close to the convective heat transfer coefficient?

8.      The description and explanation of equations in section 2.2 are significantly lacking. I recommend a thorough revision.

9.      You examine nine cases. I do not find the description of these nine cases sufficient. (section 2.4 and Figure 5)

10.  For consistency, in Figure 13, you should use a ‘U’ value (unit: W/m²K) instead of ‘R_cr’ and ‘R_slab’ [likely (since not specified) m²K/W], especially if ‘h’ [unit: W/m²K] is used.

11.  Where are the light fixtures located? If on the ceiling, how do they affect the results?

12.  The validation of the results is significantly lacking.

I hope these comments are helpful for the improvement of your manuscript.

Author Response

Dear editor, I attach the document with the answers, I hope it will resolve your doubts.
The Authors

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript under review presents an investigation into the optimization of airflow distribution in a ventilated hollow core slab system aimed at reducing cooling energy demand in residential buildings. The topic is relevant and timely, given the increasing focus on energy efficiency and sustainable building practices. However, the manuscript requires significant revisions before it can be considered for publication. The primary reasons for recommending a major revision are as follows:

Scientific Significance: The study currently reads more like a case study than a rigorous scientific research paper. The scientific significance and broader applicability of the findings are not clearly articulated. The manuscript needs to better position its contributions within the existing body of literature and emphasize the novel aspects of the research.

Validation: The computational fluid dynamics (CFD) simulations presented in the study are not validated against experimental data. Validation is crucial to establish the credibility and reliability of the simulation results. Without experimental validation, the findings of the study remain speculative.

Conclusions: The conclusions drawn in the manuscript are not sufficiently concrete. The study does not provide clear, actionable insights or recommendations based on the findings. The conclusions should be strengthened to reflect the significance and implications of the research outcomes.

Other Concerns:

Other Concerns:

- Page 3 Line 110-112: The same sentence appears twice. Please revise to eliminate redundancy.

- Page 4 Line 121-122: The statement "Therefore, since the upper slab is much better insulated than the existing lower deck slab, it can be considered adiabatic so in the computational model the air exchanges heat only with the lower slab, which is kept at a constant imposed temperature of 310K." is problematic. If the roof is exposed to the sun, then solar radiation during summer is strong enough to conduct heat from the outer surface to the inner one. Thus, the upper surface of the roof cannot be considered adiabatic even with good insulation. Additionally, the authors need to justify the imposed temperature of the lower surface. Why was 310K chosen?

- Page 6 Line 188-189: The statement "The phenomenon under study is forced convection; therefore, the velocities are large enough so that all buoyancy effects are negligible and gravity is ignored" requires justification. How large are the velocities? The authors need to provide evidence to support the neglect of natural convection.

- "The convergence criterion imposed on all residual equations was greater than 10−6." This sentence is unclear. The authors should clarify what convergence criteria were used for the simulations.

- Figure 3: Clarification is needed on whether the first turbulence model is Realizable k-omega.

- Figures Quality: Many of the figures are blurred. Consider replacing these figures with higher resolution versions to improve clarity.

 

Comments on the Quality of English Language

The quality of the language is ok.

Author Response

Dear editor, I attach the document with the answers, I hope it will resolve your doubts.
The Authors

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors,

The article has improved significantly. I have only a few formal comments, which you might need to discuss with the journal's editorial team:

1. The placement of the Nomenclature section might not be best suited for page 3, at the end of the Introduction. I usually place it before the References section.
2. There are several instances where pages are partially empty, e.g., on pages 9, 11, 13, 16, and 18.

 

Author Response

Dear Reviewer

Thank you for your positive feedback and for noting the significant improvements in our manuscript. We appreciate your remaining formal comments and have addressed them as follows:

1. Nomenclature Section Placement: We have moved the Nomenclature section to before the References section, as per your recommendation.

2. Empty Pages: The instances of partially empty pages, such as on pages 9, 11, 13, 16, and 18, were included to facilitate easier reading. LaTeX tends to fill all available space, which can result in text appearing on one page and the associated figures on the previous page, complicating the reading process. However, in the revised version, we have allowed LaTeX to automatically place tables and figures, ensuring they are included where there is available space.

We hope these adjustments meet your expectations and enhance the readability and overall quality of our manuscript.

The Authors

Reviewer 2 Report

Comments and Suggestions for Authors

All my comments have been carefully addressed. Therefore, I recommend acceptance.

Author Response

Dear Reviewer

Thank you very much for your review and for your positive feedback. We are pleased to hear that all your comments have been addressed and that you recommend our manuscript for acceptance.

The Authors