Study on Ignition Characteristics of Microblog Radiation Ignitor

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

 

• Introduction:
• Provide a more explicit discussion on the novelty and primary contribution of the study compared to existing research.
• Add several citations here (every statement made must be justified):

“The traditional ignition technology on aeroengines uses spark plugs to dis-charge electricity to ignite the gas-oil mixture. However, this ignition method has a narrow ignition boundary and is greatly affected by the speed and altitude of the aircraft. Once the engine stops at high altitude, it is difficult to ignite it again and it is necessary to lower the altitude before ignition can be successful. In recent years, microwave plasma ignition technology has gradually developed, in which microwave-assisted spark plug ignition combines the advantages of traditional spark plugs and plasma ignition technology and has strong practicality.

The research on microwave-assisted spark plug ignition started earlier abroad. The University of California, Berkeley, Imagineering Company in Japan, and the Advanced Science and Technology Research Institute in South Korea con-ducted a series of numerical simulation and experimental research on microwave-assisted spark plug ignition.”

• When discussing prior works, please emphasize their limitations or gaps that your research aims to address.

• Experimental Setup:
• Add a detailed table to summarize the main experimental parameters.
• m³ and not m3.
• In Figure 1, please indicate more clearly which components correspond to the microwave emission system and the oil supply system.

• Results and Discussion:
• Strengthen the quantitative comparison of results, especially when discussing the ignition delay time reductions across varying conditions.
• Include error analysis or uncertainties in measurements to enhance the credibility of results.

• Figures and Tables:
• Improve Figure 8, 9, 12 quality.
• Normalize the formatting of figures and tables.
• The units of measurement should be enclosed in square brackets, not round brackets. For example, use time [ms] instead of time (ms).
• In Figure 9, the unit of measurement for 'Flame area value' is not provided.

• Conclusions:
• Avoid reiterating the entire results section. Instead, focus on the broader implications and applications of the findings.
• Discuss potential future work or unanswered questions.

• Supplementary Sections:
• Before the 'References' section, please include a table of acronyms (‘Nomenclature’).
• Complete missing sections (e.g., "Funding," "Data Availability Statement," "Conflicts of Interest") as per journal requirements.

 

 

 

Author Response

Thank you again for reviewing this paper. Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The following statement in the introduction need to be rewritten and it should be clear and try to avoid general statements “The research on microwave-assisted spark plug ignition started earlier abroad. The University of California, Berkeley, Imagineering Company in Japan, and the Advanced Science and Technology Research Institute in South Korea con-ducted a series of numerical simulation and experimental research on microwave-assisted spark plug ignition”

The calibration of the various measurement and acquisition devices, along with a discussion of potential errors, should be included.

·         What is the upper threshold of microwave pulse frequency  and what happens to  ignition delay time, and how does this threshold vary with other operational parameters such as air flow rate and residual gas coefficient?

·         The conclusion effectively summarizes the study's findings, providing valuable insights into the influence of microwave-assisted ignition on ignition delay and flame propagation. However, discussing a broader range of operational parameters and their potential impact could enhance the understanding of the system's performance and guide further improvements for practical applications.

·       The references cited in this study are limited, and several recent studies are not included. Incorporating the latest references will enhance the understanding of the topic and provide readers with up-to-date resources for further exploration.

Comments on the Quality of English Language

The concepts and English Language is clear for understanding the concepts however,  there are some redundancy in the usage of words and statements for example "Ignition characteristics of Microblog radiation" is repeated several times. 

Some Sentences are over complexed, can be expressed in a simplified and clear form. 

Author Response

Thank you again for reviewing this paper. Please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

Manuscript Title: Study on Ignition Characteristics of Microblog Radiation Ignitor

 

Authors: Hao Zeng, Changqin Fu, Zhiyu Zhao

Journal: Aerospace (MDPI)

Manuscript id: aerospace-3352171

Overall Comments

The authors have investigated the ignition characteristics of a microblog radiation ignitor device. A model combustion chamber was used to perform experimental studies where a high speed camera was used to report the findings. Parameters, including different airflow rates, residual gas coefficients, and microwave parameters on the ignition process, were studied. The work is interesting, but the following comments need to be addressed before acceptance for publication.

Specific Comments

1.     The first line of the Abstract has repetition of information, which can be easily ignored by restating the line as, “In order to study the ignition characteristics of the microblog radiation ignition device, an experimental study was carried out.”

2.     The Abstract fails to explain what the authors are trying to achieve. A single sentence statement explaining the need and why the study is being carried out is required in the Abstract.

3.     The terms abroad and domestic do not make sense, as this is an international journal you are trying to publish your manuscript, and based on the publisher, you can also be foreign. Please rectify these terms and use specific country name in place of “domestic”.

4.     The literature of developing microwave assisted spark plug ignition is shown in the literature. However, the advantage of this process is not clear. Does this help ignite the engine at higher altitudes? Have there been any hypothesis developed, or studies conducted? Nothing is clear about the need and advantages of this microwave-based method.

5.     Literature fails to highlight the difference between the studies already carried out and the current study. In other words, the novelty of the work has not been established.

6.     The testing equipment is well detailed. However, it is not clear which standard this equipment and the testing procedure follows. If there are no standards, then the justification of using this method needs to be detailed further.

7.     Certain ranges for each parameter have been studied, without the explanation on any of the values. The authors need to justify each of the ranges studied in the manuscript.

 

8.     The authors have stated, “In the combustion chemical reaction, the cracking of aviation kerosene produces a large amount of CH radicals, whose corresponding wavelength is 431.4nm”. However, no references are present. Did the authors measure the wavelength, if so, then how? If this is from literature, please refer.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The following comments on language and grammar need to be addressed.

1.     It should be “3.6 m³/min, and not “3.6 m3/min”.

2.     The statement, “The gas supply system consists of a variable frequency screw air compressor, a gas storage system, a cold dryer, a filter, a gas flow controller, etc.” must be completed and the term “etc.” removed.

3.     All unit systems should be rectified, as the majority of them are missing the superscripts.

4.     The subscripts are also missing from all the abbreviations.

 

5.     Page numbers are not complete from Page 10, please rectify.

Author Response

Thank you again for reviewing this paper. Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have answered the comments, but there are new comments that must be addressed. Please find the following specific comments:

1. The first line of the paper in the Abstract starts with "This". It is not a very pleasing sight and the authors are suggested to re-write the sentence.
2. The last sentence of the Abstract reads "The results show that: as the air
   flow rate in the model combustion chamber increases, the relative reduction of the ignition delay time after applying microwave gradually decreases, and the slope of the flame area value increase curve is slightly greater than that of the flame area value increase curve without microwave application; the increase of the residual gas coefficient makes the relative reduction of the ignition delay time of the igniter after applying microwave gradually increase, and the effect is not very obvious in the rich fuel state; when the microwave pulse frequency continues to increase, the ignition delay time of the igniter decreases; as the peak power of the microwave pulse increases, the ignition delay time decreases accordingly." This is a huge sentence and very difficult to follow. Please divide into seperate sentences. May be the authors can refer to some Abstracts in reputed journals to understand how they are written.
3. The authors have answered Questions 7 and 8, but have not incorporated the comments in the manuscript. Please explain the reason in the manuscript for using the certain parameters, and put the reference "Jiang R. P., Liu G. Z., Zhang X. W. Thermal Cracking of Hydrocarbon Aviation Fuels in Regenerative Cooling Microchannels [J]. Energy & Fuels, 2013, 27(5): 2563–2577" in the manuscript beside the statement "In the combustion chemical reaction, the cracking of aviation kerosene produces a large amount of CH radicals, whose corresponding wavelength is 431.4 nm".
4. The signle sentence paragraphs can all be merged on Page 2 and anywhere else in the manuscript.
5. The Experimental set-up used in this paper (section 2.1) is not backed by any literature or standard. How do people believe on he results. Please refer in the manuscrip standards and literature references. If the references have been given once, repeat again whereever suitable.
6. The Conclusion is too big. The new paragraph is good, but the remaining three paragraphs can be condensed. Please inform the key findings only in the Conclusion.

Author Response

Please see the attachment.

Author Response File: Author Response.docx