Ignition of Wood-Based Boards by Radiant Heat

Round 1

Reviewer 1 Report

In the present study of “Ignition of Wood-based Boards by Radiant Heat”, two types of wood-based boards, the PB and OSB, were evaluated by heat flux intensity and ignition temperature.

The work of the presented article is very interesting, however, the research purpose and significance of this paper have not been clearly stated, so the authors are requested to supplement in the Abstract and Introduction sections.

What’s more, considering that this article has mainly aimed at PB and OSB boards, the title of this article was suggested to be modified as “Ignition of PB and OSB Boards by Radiant Heat”.

 

Material and Methods:

1 For the particleboard, is the study variable the thickness of the board? Why are their densities also different? How to control variables? I have the same question for the OSB board.

2 How are TGA samples selected? Due to the uneven composition in the PB and OSB boards, it is not enough to simply state the weight of the sample.

 

Results and Discussion:

1 Figure 5c, “Thicknees” should be revised as “Thickness”.

2 All “kW.m-2” in this article including the Figures should be revised as “kW•m^-2”.

3 What’s the meaning of “DTT” in Figure 9? Is it the abbreviation or trade name of PB board?

4 There is too little "discussion" in this part. What does the current result show? Are there any new findings compared with other research results?

 

Conclusion:

Line 239. The sentence cannot be the conclusion of your research, actually, heat flux has significant effects on mass loss (burning rate) and time-to-ignition of almost all types of wood-based boards.

The current conclusion is written like a test result, and the author does not draw a conclusion by judging, reasoning, or summarizing the test results.

 

Comments for author File: Comments.docx

Author Response

Thank you for the helpful comments we have incorporated into the article. We believe that editing the article has made the article better. Our repeated comments are highlight yelow and green colour in article.

Answer for Material and Methods.

We added information about moisture and samples for TGA. 

 

Answer for Results and Discussion:

Thanks for important comments. We corrected article and we added new the current results.

 

Answer for Conclusion

We added statistical analysis and our results added to conclusion.

Reviewer 2 Report

Dear author, I have carefully read your article titled "Ignition of Wood-based Boards by Radiant Heat". The thermal decomposition of structural materials and the loss of their mass and mechanical properties due to the effect of radiant heat and fire is especially important for civil engineers.  In general, the manuscript is well constructed, the experiments were well conducted, and the analysis was well performed. 

I advise the authors to take the following points into account while revising their manuscript: 

1. Please specify the novelty of your study in the introduction.

2. I recommend editing the conclusions. Please support them by discussing relevant scientific works, and you can also emphasize the importance of your work for practice, which is very important.

3. I recommend a minor revision of punctuation, also there are some typographical errors in the manuscript text, so the authors need to correct them in the revised manuscript. Authors must be taken care of the superscripts and subscripts, and abbreviations (e.g. line 95, 136, 140, 141, 180 .... )

I wish you every success in your future work.

 

Author Response

Dear Reviewer,

I am appology, that I react later, but we were so busy.

we made adjustments according to the requirements of the reviewers. 

 

Thank you for the helpful comments we have incorporated into the article. We believe that editing the article has made the article better. Our repeated comments are highlight yelow and green colour in article.

 

Answer 1:

We tried to added it.

What are the differences in the results of the research between PB and OSB due to the influence external heat flux, this article presents.

Ignition is the ability of a sample to ignite under the action of an external thermal initiator and under defined test conditions according to [53]. According to ISO 3261 [54], it is the ability of a material to ignite. Process of ignition is characterized by the time-to-ignition of sample, which depends on the ignition temperature, thermal properties of materials, sample conditions (size, humidity, orientation) and critical heat flux [55]. Definition of "ignition temperature" can be interpreted as the minimum temperature to which the air must be heated so that the sample placed in the heated air environment ignites; or the surface temperature of the sample just before the ignition point [56-58].

Separate attention is paid to the issue of simulating the ignition of wood under external heat flux from calculations of ignition parameters [59-61]. A prediction model presented in Chen at all.´s paper [62] is to study pyrolysis and ignition time of wood under external heat flux. The solution of the model provides the temperature at each point of the solid and the local solid conversion. And the time to ignition of the wood is predicted with the solution of surface temperature [63]. Chen at all.´ [62] obtained good agreement between experimental and theoretical results is obtained.

53. CEN Standard EN ISO 13943: 2018. Fire safety. Vocabulary. European Committe for Standartion, Brussels, Belgium, 2018.
54. ISO 3261:1975. Fire tests — Vocabulary. International Organization for Standardization: Geneva, Switzerland, 1995.
55. Rantuch, P.; Kacíková, D.; Martinka, J.; Balog, K. The Influence of Heat Flux Density on the Thermal Decomposition of OSB. ActaFacultatisXylologiaeZvolen res PublicaSlovaca2005,57,2, 125-134.
56. Babrauskas, V.Ignition of wood. A Review of the State of the Art. pp. 71 – 88 in Interflam 2001. Interscience Communications Ltd. London, UK, 2001.
57. Babrauskas, V.Ignition Handbook. 1^st; Fire Science Publishers. Issaquah WA, 2003.
58. Babrauskas, V. Charring rate of wood as a tool for fire investigations. Fire Saf. J. 2005, 40, 528–554. DOI: 10.1016/j.firesaf.2005.05.006
59. Baranovskiy, N.V. Mathematical simulation anthropogenic load from a linear source using partial differential equations in the context of the forests fires occurances. Advances in Differential equations and control processes 2018, 19, 237-262. DOI: 10.17654/DE019030237
60. Baranovskiy, N.V.; Kirienko, V.A. Mathematical Simulation of Forest Fuel Pyrolysis and Crown Forest Fire Impact for Forest Fire Danger and Risk Assessment. Processes 2022, 10, DOI: 10.3390/pr10030483.
61. Janssens ML. Modeling of the thermal degradation of structural wood members exposed to fire. In: Second international workshop on “structures in fire” (SiF ‘02). Christchurch, New Zealand: Department of Civil Engineering, University of Canterbury; 2002, p. 211–22.
62. Chen, X.J.; Yang, L.Z.; Ji, J.W.; Deng, Z.H. Mathematical model for prediction of pyrolysis and ignition of wood under external heat flux. Progress in natural science-materials international 2002, 12, 874-877.
63. Reszka, P.; Borowiec, P.; Steinhaus, T.; Torero, J.L. A methodology for the estimation of ignition delay times in forest fire modelling. Combustion and Flame 2012, 159, 3652-3657. DOI: 10.1016/j.combustflame.2012.08.004

 

 

Answer 2

PB and OSB are offered materials for building structures. Experts from practice ask to explain the differences in the mentioned materials not only in their physical and mechanical properties. The paper presents the results of the behaviour of the mentioned materials during heat transfer. The monitored parameters Time-to-ignition and mass loos of the mentioned materials are compared with each other and a connection between them is sought.

 

Answer 3.

Thanks for comment. We corrected it.

Reviewer 3 Report

Dear authros!

 

Your manuscript is highly inresting for readers of the Forests journal.

But there are some disadvantages of your current version of manuscript.

 

Introduction

There are too small quantity of cited works in the Introduction section. To now many interesting works have been published on topic od wood and wooden materials ignition. You shouls many earlier published works, for example, research and review articles of distingueshed scientist in ignition field as V. Babrauskas, taking into account his bestsaller Ignition Handbook. Also other known scientist around the world must be cited in your article. Also you must add theoretical works devoted to mathematical simulation of fire impact on wood and wooden materials, taking into account MDPI journals for the last five years at least. This is unrespectable to other scientific community to ommit published works. I think you must provide at least 60-70 cited references in your manuscript.

 

2.2 Methodology

 

Please change definition "Time-to-ignition" to definition "Ignition delay".

"Time-to-ignition" is not commonly used definition. I have never saw such definition in articles devoted to ignition topic.

Please, provide brief description of ISO 5657:1997 modified procedure taking into account description of suggested conditions to determine ignition delay.

Please, clarify why did you choose small interval of 43 - 50 kW/m2 in your reserch?

Please, provide description of statistic procedure for determination of confidential intervals based on five repetitions for each experiment.

Please, provide brief description of Mettler TA 3000 apparatus.

 

3 Results and Discussion

Please, clarify how did you determine critical temperature to obtain ignition delay? Or how you determine ignition delay? I did not understand these aspects of you research.

Please, provide in Results and Discussion set of pictures: initial view of sample, inert heating, pyrolysis, ignition, flame combustion and afterburning with corresponding timeline.

You wrote about different values for different samples with figure 5, but there are no any confidential intervals in Figure 5. How you can make any conclusions without qualitative and quantative analysis of results, presented in Figure 5. May be confidential intervals for different samples are overlapped and your conclusions are wrong and errorous.

The same situation with Figure 6. There are no confidential intervals and it is possible that your conclusions are wrong. Please provide approximation lines in Figure 6.a also.

Why did you choose line approximation for dependences of ignition delay on thickness? You should support such decision.

 

Please, provide confidential intervals for data on Figure 7 and Figure 9.

Pay attention, that Figure 8 is missing in your manuscript.

 

You must understand that your research is poor sounding without uncertainty analysis with confidential intervals in Figures.

Conclusion

Please, improve Results and Discussion section and then write a Conclusion section. Maybe, with confidential intervals analysis you will obtain another conclusions. Please, examine your conclusions.

 

References

There are too small quantity of cited works in the Introduction section. To now many interesting works have been published on topic od wood and wooden materials ignition. You shouls many earlier published works, for example, research and review articles of distingueshed scientist in ignition field as V. Babrauskas, taking into account his bestsaller Ignition Handbook. Also other known scientist around the world must be cited in your article. Also you must add theoretical works devoted to mathematical simulation of fire impact on wood and wooden materials, taking into account MDPI journals for the last five years at least. This is unrespectable to other scientific community to ommit published works. I think you must provide at least 60-70 cited references in your manuscript.

 

I think you must make a major revision of your manuscript.

Author Response

Reviewer 2

Dear Reviewer,

I am appology, that I react later, but we were so busy.

 

we made adjustments according to the requirements of the reviewers. This article is attached in file.

 

Thank you for the helpful comments we have incorporated into the article. We believe that editing the article has made the article better. Our repeated comments are highlight yelow and green colour in article.

 

Introduction answer

Thank you for the important comments. We have added the mentioned published works on topic od wood and wooden materials ignition.

You are right about the distinguished scientist V. Babrauskas and his publication Ignition Handbook, which we have at our disposal. We use the theoretical knowledge from the mentioned publication mainly in the research of flammable liquid fires: : https://www.webofscience.com/wos/ccc/full-record/CCC:000516827400032

We added the following text to the introduction:

What are the differences in the results of the research between PB and OSB due to the influence external heat flux, this article presents.

Ignition is the ability of a sample to ignite under the action of an external thermal initiator and under defined test conditions according to [53]. According to ISO 3261 [54], it is the ability of a material to ignite. Process of ignition is characterized by the time-to-ignition of sample, which depends on the ignition temperature, thermal properties of materials, sample conditions (size, humidity, orientation) and critical heat flux [55]. Definition of "ignition temperature" can be interpreted as the minimum temperature to which the air must be heated so that the sample placed in the heated air environment ignites; or the surface temperature of the sample just before the ignition point [56-58].

• CEN Standard EN ISO 13943: 2018. Fire safety. Vocabulary. European Committe for Standartion, Brussels, Belgium, 2018.
• ISO 3261:1975. Fire tests — Vocabulary. International Organization for Standardization: Geneva, Switzerland, 1995.
• Rantuch, P.; Kacíková, D.; Martinka, J.; Balog, K. The Influence of Heat Flux Density on the Thermal Decomposition of OSB. ActaFacultatisXylologiaeZvolen res PublicaSlovaca2005,57,2, 125-134.
• Babrauskas, V.Ignition of wood. A Review of the State of the Art. pp. 71 – 88 in Interflam 2001. Interscience Communications Ltd. London, UK, 2001.
• Babrauskas, V.Ignition Handbook. 1^st; Fire Science Publishers. Issaquah WA, 2003.
• Babrauskas, V. Charring rate of wood as a tool for fire investigations. Fire Saf. J. 2005, 40, 528–554. DOI: 10.1016/j.firesaf.2005.05.006
• Sorry, simulations are not our cup of coffee, but we have colleagues who will use our experimental results for simulation purposes.

We added the following text to the article:

Separate attention is paid to the issue of simulating the ignition of wood under external heat flux from calculations of ignition parameters [59-61]. A prediction model presented in Chen at all.´s paper [62] is to study pyrolysis and ignition time of wood under external heat flux. The solution of the model provides the temperature at each point of the solid and the local solid conversion. And the time to ignition of the wood is predicted with the solution of surface temperature [63]. Chen at all.´ [62] obtained good agreement between experimental and theoretical results is obtained.

 

• Baranovskiy, N.V. Mathematical simulation anthropogenic load from a linear source using partial differential equations in the context of the forests fires occurances. Advances in Differential equations and control processes 2018, 19, 237-262. DOI: 10.17654/DE019030237
• Baranovskiy, N.V.; Kirienko, V.A. Mathematical Simulation of Forest Fuel Pyrolysis and Crown Forest Fire Impact for Forest Fire Danger and Risk Assessment. Processes 2022, 10, DOI: 10.3390/pr10030483.
• Janssens ML. Modeling of the thermal degradation of structural wood members exposed to fire. In: Second international workshop on “structures in fire” (SiF ‘02). Christchurch, New Zealand: Department of Civil Engineering, University of Canterbury; 2002, p. 211–22.
• Chen, X.J.; Yang, L.Z.; Ji, J.W.; Deng, Z.H. Mathematical model for prediction of pyrolysis and ignition of wood under external heat flux. Progress in natural science-materials international 2002, 12, 874-877.
• Reszka, P.; Borowiec, P.; Steinhaus, T.; Torero, J.L. A methodology for the estimation of ignition delay times in forest fire modelling. Combustion and Flame 2012, 159, 3652-3657. DOI: 10.1016/j.combustflame.2012.08.004

 

2.2 Methodology

Please change definition "Time-to-ignition" to definition "Ignition delay". "Time-to-ignition" is not commonly used definition. I have never saw such definition in articles devoted to ignition topic.

Answer:

We are very sorry, but the specified parameter „time-to-ignition“ is in use. We have already published several works and used the following parameter:

• DOI: 10.3390/polym14091648
• At the same time, the given parameter is used in the following works:
• DOI: 10.12913/22998624/65130
• DOI: DOI10.1016/S0255-2701(96)04181-5
• DOI: 10.1007/s10973-013-3278-x
• DOI: DOI10.1016/0010-2180(91)90009-Z

 

You are the first opponent to make this request. The stated request is inspiring for us and we will certainly pay due attention to it.

I found paper: Ignition of various wood species by radiant energy (https://www.researchgate.net/publication/251398966_Ignition_of_various_wood_species_by_radiant_energy ), where is term „igniton delay“. But autors also used term „ignition time regrading to depending to moisture content  samples.

 

Please, provide brief description of ISO 5657:1997 modified procedure taking into account description of suggested conditions to determine ignition delay.

Answer:

The presented research is part of the project solution of the effect of radiant heat on wooden materials. He was elected to the post according to ISO 5657:1997. Before starting all measurements, the test equipment was verified in order to verify its functionality and operational reliability during measurement. Published in:

• DOI: 1 0.3390/polym14091648

The essence of the test method according to ISO 5657 was to investigate the ability of the surface of the material to develop volatile gases when exposed to radiant heat and the ability of selected board materials to ignite when exposed to radiant heat flows in the presence of an ignition source. The source of ignition is the flame from the burner.

The modification of the procedure was in the method of initiation. Our method of initiation was through the regulation of radiant heat from the source.

 

Please, clarify why did you choose small interval of 43 - 50 kW/m2 in your reserch?

Answer

The value of 43 kW/m2 was chosen based on orientation experiments where the emitter itself was tested. Orientation experiments determined the minimum heat flow required to maintain flame combustion. Experiments carried out with a heat flow below 43 kW/m2 did not achieve flame combustion. A detailed interpretation is given in DOI: 1 0.3390/polym14091648

The value of 50 kW/m2 is the maximum that the experimental device can reach (DOI: DOI10.3846/13923730.2013.810169). Other authors also worked with the stated maximum value, some with a much lower one: DOI: 10.1016/j.fuel.2020.118325

 

Please, provide description of statistic procedure for determination of confidential intervals based on five repetitions for each experiment.

Answer

The ISO 5657:1997 standard states repeatability 3x. We must say that the mentioned experiments are economical and time-consuming. The obtained standard deviations (Tab2) are satisfactory for the results of the used standard. Our effort to obtain more objective values ​​was reflected in an increase in the number of measurements. Descriptive statistics were used in the Excel program, where a mathematical apparatus was prepared for the calculation parameters of descriptive statistic.

 

Please, provide brief description of Mettler TA 3000 apparatus.

Answer

TGA was performed on the basis of the procedure specified in STN EN ISO 11358: 2000. TGA samples were performed on a Mettler TA 3000 thermal analyzer with a TC 10A processor and TG 50 thermogravimetric scales. The test was performed up to a temperature of 700 °C in an air atmosphere with a flow rate of 200 ml.min-1 and with a constant heating rate of 10 °C.min-1 (according to the controlled temperature program). The accuracy of the test equipment was determined by calibration with a value of - 2.4% to + 8.2%. and the change in mass was measured as a function of temperature.

Measurements can be made in the atmosphere: air, oxygen, nitrogen

The flow can be regulated from 10 to 50 ml.min-1

The heating speed can be regulated from 1-30°C.min-1.

 

3 Results and Discussion

Please, clarify how did you determine critical temperature to obtain ignition delay? Or how you determine ignition delay? I did not understand these aspects of you research.

Answer:

The critical temperature was not the goal of the presentation of the results. But its determination is explained in the article: :. DOI: https://doi.org/10.3390/polym14091648 [71]

 

Our answer on Comment of 3. Results and Discussion :

 

we prepared box plots to the obtained results and looked for the indicated overlap. Our data describes the fact that:

As the heat flux increases, the time-to-ignition and mass loss parameters for PB and OSB are significantly comparable. This fact also applies to the thickness. With increasing thickness, the investigated values approach.

 

The box plots added to Figure 7 shows the same tendency for the burning rate to increase. The values of 43,44, 45 and 46 kW.m-2 have exactly the same burning rate values, significant changes occurring at heat flows of 48 -50kW.m-2.

 

Our results show that as the thickness  samples increases, the differences in the behavior of the samples disappear under action radiant heat , which can be seen in fig. 6. Practice should take into account the importance of thickness when applying these materials in building structures or elements.

 

Pay attention, that Figure 8 is missing in your manuscript. Answer: Sorry, this is mistake

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Could you please answer my questions point to point?

Author Response

Dear Reviewer,

Thank you for the comments we have incorporated into the article. We believe that editing the article has made the article better. Our repeated comments are highlight yelow and green colour in article. We tried to answer on your comments and questions following:

Comment of Reviewer:

In the present study of “Ignition of Wood-based Boards by Radiant Heat”, two types of wood-based boards, the PB and OSB, were evaluated by heat flux intensity and ignition temperature.

The work of the presented article is very interesting, however, the research purpose and significance of this paper have not been clearly stated, so the authors are requested to supplement in the Abstract and Introduction sections.

What’s more, considering that this article has mainly aimed at PB and OSB boards, the title of this article was suggested to be modified as “Ignition of PB and OSB Boards by Radiant Heat”.

Answer:

We made title article on “Ignition of PB and OSB Boards by Radiant Heat”.

We added the following text to the introduction:

What are the differences in the results of the research between PB and OSB due to the influence external heat flux, this article presents.

Ignition is the ability of a sample to ignite under the action of an external thermal initiator and under defined test conditions according to [53]. According to ISO 3261 [54], it is the ability of a material to ignite. Process of ignition is characterized by the time-to-ignition of sample, which depends on the ignition temperature, thermal properties of materials, sample conditions (size, humidity, orientation) and critical heat flux [55]. Definition of "ignition temperature" can be interpreted as the minimum temperature to which the air must be heated so that the sample placed in the heated air environment ignites; or the surface temperature of the sample just before the ignition point [56-58].

• CEN Standard EN ISO 13943: 2018. Fire safety. Vocabulary. European Committe for Standartion, Brussels, Belgium, 2018.
• ISO 3261:1975. Fire tests — Vocabulary. International Organization for Standardization: Geneva, Switzerland, 1995.
• Rantuch, P.; Kacíková, D.; Martinka, J.; Balog, K. The Influence of Heat Flux Density on the Thermal Decomposition of OSB. ActaFacultatisXylologiaeZvolen res PublicaSlovaca2005,57,2, 125-134.
• Babrauskas, V.Ignition of wood. A Review of the State of the Art. pp. 71 – 88 in Interflam 2001. Interscience Communications Ltd. London, UK, 2001.
• Babrauskas, V.Ignition Handbook. 1^st; Fire Science Publishers. Issaquah WA, 2003.
• Babrauskas, V. Charring rate of wood as a tool for fire investigations. Fire Saf. J. 2005, 40, 528–554. DOI: 10.1016/j.firesaf.2005.05.006
• Sorry, simulations are not our cup of coffee, but we have colleagues who will use our experimental results for simulation purposes.

We added the following text to the article:

Separate attention is paid to the issue of simulating the ignition of wood under external heat flux from calculations of ignition parameters [59-61]. A prediction model presented in Chen at all.´s paper [62] is to study pyrolysis and ignition time of wood under external heat flux. The solution of the model provides the temperature at each point of the solid and the local solid conversion. And the time to ignition of the wood is predicted with the solution of surface temperature [63]. Chen at all.´ [62] obtained good agreement between experimental and theoretical results is obtained.

• Baranovskiy, N.V.; Kirienko, V.A. Mathematical Simulation of Forest Fuel Pyrolysis and Crown Forest Fire Impact for Forest Fire Danger and Risk Assessment. Processes 2022, 10, DOI: 10.3390/pr10030483.
• Janssens ML. Modeling of the thermal degradation of structural wood members exposed to fire. In: Second international workshop on “structures in fire” (SiF ‘02). Christchurch, New Zealand: Department of Civil Engineering, University of Canterbury; 2002, p. 211–22.
• Chen, X.J.; Yang, L.Z.; Ji, J.W.; Deng, Z.H. Mathematical model for prediction of pyrolysis and ignition of wood under external heat flux. Progress in natural science-materials international 2002, 12, 874-877.
• Reszka, P.; Borowiec, P.; Steinhaus, T.; Torero, J.L. A methodology for the estimation of ignition delay times in forest fire modelling. Combustion and Flame 2012, 159, 3652-3657. DOI: 10.1016/j.combustflame.2012.08.004

 

Material and Methods:

1 For the particleboard, is the study variable the thickness of the board? Why are their densities also different? How to control variables? I have the same question for the OSB board?

Answer:

Density as a ratio of weight to volume should be maintained for PB and OSB for all thickness. In general, OSB and PB are heterogeneous material. The results would not be exactly the same.We added information about density of samples. You can see in Table 1, that density does not same value for the PB thickness. We found too high density values for 15 mm thickness PB samples too late.

Density of OSB  samples for all thickness are relatively same.

We need this values as facts, becouse we toke his sample from praxe.

2 How are TGA samples selected? Due to the uneven composition in the PB and OSB boards, it is not enough to simply state the weight of the sample.

Answer:

Thanks for comment. We added: The samples for TGA were specific prepared by disintegration.

 

Results and Discussion:

Answers:

1 Figure 5c, “Thicknees” should be revised as “Thickness”. – Sorry, we corrected it.

 

2 All “kW.m-2” in this article including the Figures should be revised as “kW•m-2”.

– Sorry, we corrected it.

3 What’s the meaning of “DTT” in Figure 9? Is it the abbreviation or trade name of PB board?

Yes, the corrected mark is PB. Sorry, we corrected it in whole article.

4 There is too little "discussion" in this part. What does the current result show? Are there any new findings compared with other research results?

We tried to add discussion and added new the current results.

Thanks for important comments. We corrected article and we added new the current results.

 

Conclusion:

Line 239. The sentence cannot be the conclusion of your research, actually, heat flux has significant effects on mass loss (burning rate) and time-to-ignition of almost all types of wood-based boards.

The current conclusion is written like a test result, and the author does not draw a conclusion by judging, reasoning, or summarizing the test results.

Answer:

Yes and We added statistical analysis to confirm the influence of factorsand our results is in Conclutions:  „The heat flux and thickness had a significant effect only on time-to-ignition“

We added : Our results show that as the thickness samples increases, the differences in the be-havior of the samples disappear under action radiant heat, which can be seen in Fig. 6. Practice should take into account the importance of thickness when applying these materials in building structures or elements.

Reviewer 3 Report

Dear authors!

Thank you for revised manuscript.

The majority of my remarks were addressed.

Minor comments:

Introduction, ref. 59 is not devoted to ignition task. Please, remove this ref from References list.

Methodology, In my opinion, term time-to-ignition is less suitable than ignition delay.

 

I suggest minor revision

Author Response

Dear Reviewer,

Thank you for the comments and opinion.

We removed Ref. 59 from References