Numerical Investigation of the Effects of Diffusion Time on the Mechanisms of Transition from a Turbulent Jet Flame to Detonation in a H2-Air Mixture
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThis manuscript numerically simulates the onset of detonation process caused by turbulent jet flames in non-uniform mixtures. The initiation mechanism is related to the fuel concentration and the diffusion time. The numerical flow field clearly describes types of initiation modes. However, the manuscript has the following issues that need improvement:
1- Need to provide the shape, size and location of ignition kernel.
2- Motivation to consider the mixtures with diffusion time = (3, 5 and 60) and geometry specified in the study is missing.
All color figures are really nice, but difficult to interpret. The results of the present research were not compared with previous researches so that the results are not convincing.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis numerical study presents the effects of the fuel diffusion time on the detonation initiation as well as the flame acceleration in uniform and stratified H2-Air mixtures with 22.5% and 30% average concentration. In a channel of blockage ratio 0.9, the simulated flame structure was given in terms of temperature and pressure contours. Through the time-wise observation of the flame propagation, the phenomenon that the flame front overtakes the shock front could be clearly found with the DDT behavior strongly depending on the fuel diffusion time and the mixture concentration: this kind of information will be pretty much beneficial to the community concerned with the safety engineering.
Comments on the Quality of English Language
The 'Introduction' part shall be carefully revisited especially focusing on the 'Tense' between the main clause and subordinate clause.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
