Analysis of Hydrogen Filling of 175 Liter Tank for Large-Sized Hydrogen Vehicle

Round 1

Reviewer 1 Report

This is a good paper that should be interested for people engaged in the development and deployment of CGH2 solutions for larger systems.

The language and grammar can benefit from some minor corrections (e.g. in Line 70).

It could be useful if the authors could elaborate on the implications of the results from a safety perspective, e.g. to what extent different types of tanks are suitable for rapid filling.

 

Author Response

This paper has been reconstructed as the reviewers’ suggestion. We, the authors, really appreciate the reviewers’ helpful comments. We feel that this paper has become more rigorous and well-constructed after implementing the suggested parts in the manuscript. The revisions to the manuscript were marked up with yellow color

Author Response File: Author Response.docx

Reviewer 2 Report

Reviewer comments for applsci-1696185

 

The paper entitled “Analysis of Hydrogen Filling of 175-L Tank for Large-sized Hydrogen Vehicle” performed numerical parametric studies on hydrogen filling for the large hydrogen tank of 175 L to estimate the hydrogen gas behavior in the hydrogen tank under various conditions of state of charge of pressure and ambient temperature.

 

The article topic is of interest to the research community; however, this reviewer has several comments that need to be fully addressed before accepting the article for publication. Therefore, my decision is “major revision”. My specific comments are:

 

• Page 2, line 46: k-e should be modified to k-epsilon. Lines 141 and 145-146 and 259 have the same typo.
• Page 2, line 67: ………….Although lots of studied for the hydrogen……. Should be modified to: Although many studies have been conducted for ……………………..
• Page 2, lines 70-71: the sentence is weak and not clear: …..There has the difference of hydrogen behavior in the tank between small capacity and large capacity.
• In general, the English of the article needs significant improvements, as there are several mistakes, poor sentences and repeated sentences.
• The reviewed previous research articles are listed without providing specific details on their advantages and disadvantages. The review of previous work should be provided in a way to support the objectives of the authors’ articles.
• Assumption (1) is not clear; how the properties can be considered constant when the pressure is high and the temperature changes? This assumption has significant effect on the results and therefore should be revisited and made clear and justified.
• In assumption (3), the authors cited Fig. 3 and Table 3 before introducing Figs 1, 2 and Tables 1, 2. This must be in sequence of appearing.
• In section 3.3, the authors started talking about the numerical mesh while the geometry is not shown. A figure of the geometry with the numerical grid must be provided. Also, the authors used 2-D model but they are saying that they solved the problem using finite volume method; it should be finite difference method.
• Lines 147 to 153, how important is the anisotropy? Should it be considered or can it be neglected to justify not using RSM model?
• Figure 2. Representative velocity vector………msut be vectors.
• Conclusion # 2 is not a conclusion, it is a statement or description of the work.
• Last conclusion: although the authors have decided to neglect the gravity effects, now they are saying that the gravity effect will be studied in the future. So how confident are the authors in the results of the current study?

 

 

Author Response

This paper has been reconstructed as the reviewers’ suggestion. We, the authors, really appreciate the reviewers’ helpful comments. We feel that this paper has become more rigorous and well-constructed after implementing the suggested parts in the manuscript. The revisions to the manuscript were marked up with yellow color

Author Response File: Author Response.docx

Reviewer 3 Report

The presented work is a numerical study on refuelling of a commercial 175 L compressed hydrogen gas cylinder at varied pressures and ambient temperature conditions. The subject matter is relative to the journal publication and is worth investigating. I found much of the paper interesting and came way with many questions to recommend this manuscript in its current form. Therefore, a minor revision is warrant. The paper could be accepted after the minor revision and addressing the following comments:

 

1. The abstract usually has to be written in the 'present tense' and not in the 'past tense'. The entire abstract needs to be re-written in the 'present tense'.
2. The conclusive results must be added in the last portion of the abstract.
3. In Line 27, replace 'implications for' with 'implications on'.
4. In the entire manuscript CGH2 must be replaced with CGH₂.
5. It is suggested to compare the obtained numerical results for compressed H₂ storage tanks with commercially available metal-hydride based H₂ tanks. 

Author Response

This paper has been reconstructed as the reviewers’ suggestion. We, the authors, really appreciate the reviewers’ helpful comments. We feel that this paper has become more rigorous and well-constructed after implementing the suggested parts in the manuscript. The revisions to the manuscript were marked up with yellow color

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The English still needs some improvements: for example: "Although many studied has been conducted for the hydrogen.... should be many studies have been....

"There is the difference of hydrogen behavior in the tank between small and large volume."  No need for this sentence at all.

Proofread the whole article one more time.