Influence of Wooden Compartment’s Fuel Moisture Content on Time to Flashover: An Experimental and Numerical Study

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper presents the experimental study on the  time to flashover influecned by FMC with validated FDS results, which is cruial for the Fire Safety Commu. The paper can be acceppted after addressing the following comments:

1. Introduction needs to be improved, the mechanism and bebavior of fire flashover should be reviewed instead of the time to flashover reviews in results section.

2.Dimensionless time is suggested to analyze the quantitative effects of different FMCs on flashover in more quantitative way.

3. In the Fig 8, the exp. data seem not good or fit with FDS, please explain.

4.It's not suitable for applying the linear regression model which is not good fit for exp data as Q3 comment, to calculate or predict the time to flashover in this study. Please use a more reliabe way to predict the flashover domonited by FMCs.

Author Response

Dear Sir, 

Please see the attachment. Thank you. 

Best Regards

Prof. Sanjay K. Khattri

 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This paper presents the influence of fuel moisture content in wooden compartment fire on the time to flashover through experimental measurements and numerical modeling. The study is conducted on a 1/8^th scale model of an ISO 9750-1 room 9 different moisture content levels. Time to flashover is a very important parameter in compartment fire spread studies to understand the rate of fire spread and devise a fire suppression plan. As presented in this study, the flashover time is dependent on the amount of moisture in the fuel that controls the pyrolysis of the fuel. The experimental results are presented with multiple location temperature measurements in the scale model. Numerical study is conducted using FDS and the results show good agreement with the experimental results. This is a valuable study for the broader fire safety community, and I support the work the authors have done.

 

Below are my comments/questions for the authors.

1.       Can the authors comment on why they selected this specific range of the moisture content for their study?

2.       Figure 2 needs improvement. I suggest the authors to annotate major dimensions and provide better representation for the location of the thermocouples.

3.       Can the authors’ comment on the results at 11.4% FMC? Why are these results outliers? If it is specifically related to issues with experimental measurements, I suggest authors to remove this data point as it can be distracting from the other results.

4.       How was radiation source term modeled? What assumptions went into modeling soot vs the gas radiation?

5.       Can the authors comment on the applicability of Eq. (16) to a bigger scale model? Have they tested the validity of this regression model on a bigger scale model and verified that it is independent of the geometry? If the authors’ state that these results can be used by firefighters, I would like to see more evidence how this simplified regression model performs on a full-scale ISO 9750-1 room in a numerical model.

6.       The paper needs heavy improvement on grammar and spell check. There are a lot of spelling errors and I highly recommend the authors to run a spell check on their papers before submitting it.

Comments on the Quality of English Language

The paper needs heavy improvement on grammar and spell check. There are a lot of spelling errors and I highly recommend the authors to run a spell check on their papers before submitting it.

Author Response

Dear Sir, 

Please see the attachment. Thank you. 

Best Regards

Prof. Sanjay K. Khattri

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

This manuscript investigates the effects of fuel moisture content on the time to flashover, crucial in fire safety analysis. Experiments and simulations of an ISO 9750-1 room model at 1/8th scale were performed by varying the wooden compartment boundaries' moisture content between 5% and 16%. The results show a linear increase in time to flashover with fuel moisture content. An empirical model to predict the time to flashover according to the moisture content was developed. However, the conclusion part of the paper is only the description of the results, which lacks an in-depth discussion on the between fuel moisture content and the time to flashover or any quantitative conclusions and suggestions. Therefore, I suggest the manuscript needs some major changes before it can be accepted.

This revised paper needs further revision for publication as follows:

1. For the title of this article, the author should limit the region. In the introduction, the author explains that wooden houses are plentiful in Norway. This article should be the author's research mainly for the Norwegian region.

2. The research in this paper is only an experiment on the already-known conclusions. It is a commonly known truth that the higher the water content, the longer the combustion time, the author conducted experiments to verify it, but the author did not conduct in-depth research and analysis of the reasons.

3. The author carried out the influence of water content on the flashover, how to determine the size of the structure, the size of the structure is large and small, once a fire occurs, the structure size, water content, and fire source location and other factors are mutually affected, the author only studied the effect of water content on the fire is not very large.

4. Figure 2 is so rough that there is nothing useful to be learned from it. The author should label each part of the picture. In addition, the authors may be able to give pictures of real experiments.

5. For the design of the scale model used in this paper, the author can not give more details, the author should supplement.

6. What is the author's basis for choosing these different wall fuel moisture content? The author should fill in the details.

7. The author also does not give experimental phenomena, which should be supplemented.

8. This article is not very innovative and is not recommended to be published as a research paper, if published, it can be published as a Tech note.

Comments on the Quality of English Language

None

Author Response

Dear Sir, 

Please see the attachment. Thank you. 

Best Regards

Prof. Sanjay K. Khattri

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The paper can be accepted as all comments are well responsed.

Author Response

Dear Sir, 

We appreciate the reviewer for the positive, constructive review which has significantly improved the quality and readability of our manuscript. We have revised our paper according to the reviewer’s comments and suggestions. Please see the revised manuscript. 

Thank you. We wish you and your family Merry Christmas. 

Best Regards
Prof. Sanjay K. Khattri

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

All my comments are addressed and this paper can be accepted. 

 

Comments on the Quality of English Language

English language and spell check still needs improvement. I can see few spelling mistakes. "enthaly" vs "enthalpy" is one example.

Author Response

Dear Sir, 

We appreciate the reviewer for the positive, constructive review which has significantly improved the quality and readability of our manuscript. We have revised our paper according to the reviewer’s comments and suggestions. We appreciate your attention to detail and would like to inform you that we have taken the necessary steps to improve the language throughout the paper.  Please see the revised manuscript.  

Thank you. We wish you and your family Merry Christmas. 

Best Regards
Prof. Sanjay K. Khattri

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The author revised the questions raised by the reviewer, but there are still some suggested changes that cannot explain the problem. Some modifications still need to be made.

1. It can be seen from Fig.2 that after a 1/8 scale, the scale model is very small, and whether it can reflect the real fire response. Such a small-scale model is not seen, the author should supplement the relevant research.

2. The relevant modifications made by the author in the article need to be marked out, so as to facilitate the positioning of the specific location in the manuscript. Determine whether the author has modified the manuscript.

3. At present, there have been many fire test studies based on prototype structures. The author has also carried out such a large scale, and the correctness of the research needs to be verified.

Author Response

Dear Sir, 

We appreciate the reviewer for the positive, constructive review which has significantly improved the quality and readability of our manuscript. We have revised our paper according to the reviewer’s comments and suggestions. We appreciate your attention to detail and would like to inform you that we have taken the necessary steps to improve the language throughout the paper.  Please see the revised manuscript.  

Please refer to the lines 353 through 367 in the Section 4 of the revised manuscript, as these lines address the reviewer's suggestions of including more examples of small-scale experiments. In this revised manuscript, we have incorporated additional references, specifically references 37, 38, and 39, which cover small-scale experiments.

Thank you. We wish you and your family Merry Christmas. 

Best Regards
Prof. Sanjay K. Khattri

Author Response File: Author Response.pdf