Effect of the Hopper Angle of a Silo on the Vertical Stress at the Cylinder-to-Hopper Transition

Round 1

Reviewer 1 Report

I have revised the manuscript "Effect of the hopper angle of a silo on the vertical stress at the cylinder-to hopper transition" by R. Marçal Gandia et al.

 

In its work, the authors experimentally study the relationship between the hopper angle and the wall stress distribution in a silo discharge process. The authors find significant evidence that hopper-angle have a nontrivial impact on the internal stress distribution, notably at 

\beta=30 degree hopper. 

 

The topic under study is relevant and has significant practical consequences. Unfortunately, its presentation is merely descriptive without attempting to justify the origin of the reported results. More importantly, the grammar and style presentation must be deeply revised.

 

Let me remark some critical points to consider:

1. Stress must be precisely defined. The reported wall forces wall are not "stresses."
2. Pressure's reported in Fig 5 (figure quality also must be improved) summarize the main work results, but are really poorly described as the temporal scale is not described, etc.
3. Something similar occurs with the results of Fig.6. The measured stress seems to affect the discharge rate, but any comment regarding this fact can be found in the text. 

 

In summary, I feel that this work perhaps contains capable results. Nevertheless, the authors must rethink its presentation to reach an acceptable quality.

Author Response

Author's Reply to the Review Report – Reviewer 1

 

Review overview

First, I would like to thank you for all your suggestions and constructive criticism. Your comments made our article with a higher quality.

I would also like to say that all your suggestions were accepted and worked on in the best possible way.

First we did all the revisions, then, to improve the quality of the English, the article was read at least 3 times with this objective.

We have greatly improved our methodology and our results and discussions. In addition, we reviewed our conclusion and contextualized our introduction.

 

 

Replies to Comments and Suggestions for Authors

 

1º point

Reviewer 1: 

The topic under study is relevant and has significant practical consequences. Unfortunately, its presentation is merely descriptive without attempting to justify the origin of the reported results. More importantly, the grammar and style presentation must be deeply revised.

 

Authors:

We agree with the reviewer, therefore, we broadened and deepened the discussions based on the findings in Figures 6, 7, 8 and 9. In addition, we revised our English in terms of grammar. In addition, we improved the quality and presentation of all figures, segmented figure 6 (now figures 6, 7 and 8), included figure 2 and figure 3.

 

2º point

Reviewer 1: 

Stress must be precisely defined. The reported wall forces wall are not "stresses."

 

Authors:

We agree with the reviewer. Stress was better conceptualized and explained. In addition to comparing with the equations of Eurocode 1, part 4.

 

3º point

Reviewer 1: 

Pressure's reported in Fig 5 (figure quality also must be improved) summarize the main work results, but are really poorly described as the temporal scale is not described, etc.

 

Authors:

We agree. The key point of our article is Figure 5 (currently Figures 6, 7, and 8). Figure 5 has been segmented and quality improved. To achieve the reviewer's suggestion, we also improved the texts in the description.

 

4º point

Reviewer 1: 

Something similar occurs with the results of Fig.6. The measured stress seems to affect the discharge rate, but any comment regarding this fact can be found in the text. 

Authors:

We agree. Figure 6 (currently Figures 9) has been improved, in addition, to meet the reviewer's suggestion, we associate and discuss further about friction stresses in the cylinder 0.25 m above the transition at discharge related to vertical stress in the stored material at the transition(pvt,t).

 

 

5º point

Reviewer 1: 

In summary, I feel that this work perhaps contains capable results. Nevertheless, the authors must rethink its presentation to reach an acceptable quality.

 

Authors:

We appreciate the suggestions of reviewer 1. All changes are presented in the .doc file sent. We completely restructured the article.

Reviewer 2 Report

In this paper, the authors elucidated the relationship of hopper angle, flow patter and the vertical stress at the cylinder-to-hopper transition in slender silos. The results for vertical stress at the cylinder-to-hopper transition in a full-scale silo obtained from assays performed on a test station using a free-flowing product were reported. Five different hopper angles were tested by filling the silo, and observing a static phase followed by complete discharge. It was found that the hopper angle influences the vertical stress at the cylinder-to-hopper transition, and the vertical stress exceeded those calculated by the standard.

1. The Introduction part should be arranged and enriched carefully, there are too many “small” paragraphs.
2. The variable A in equation (1) should be explained.
3. Figures 2-6 are not clear, the authors should provide high-resolution pictures.
4. Section 4: the discussion should be enriched and more details should be discussed.

Author Response

Author's Reply to the Review Report – Reviewer 2

 

Review overview

First, I would like to thank you for all your suggestions and constructive criticism. Your comments made our article with a higher quality.

I would also like to say that all your suggestions were accepted and worked on in the best possible way.

First we did all the revisions, then, to improve the quality of the English, the article was read at least 3 times with this objective.

We have greatly improved our results and discussions, introduction and methodology. In addition, we reviewed our conclusion.

 

 

Replies to Comments and Suggestions for Authors

 

1º point

Reviewer 2: 

The Introduction part should be arranged and enriched carefully, there are too many “small” paragraphs.

 

Authors:

We agree. We restructured our entire intro. We worked to make the paragraphs more connected and tried to better explain our references.

 

2º point

Reviewer 2: 

The variable A in equation (1) should be explained.

 

Authors:

We agree. We made a figure (Figure 2) explaining the structure of the silo and also the variable A of equation (1).

 

3º point

Reviewer 2: 

Figures 2-6 are not clear, the authors should provide high-resolution pictures.

 

Authors:

We agree. We deleted Figure 2 and in its place the new Figure 2 is in full resolution and is more self explanatory. We also changed the quality of Figure 6 (currently Figure 9), in addition to increasing the size of the written content.

 

4º point

Reviewer 2: 

Section 4: the discussion should be enriched and more details should be discussed.

 

Authors:

We agree. We deepened the discussion to associate all the results we found related to Pvt and Pw1. In addition, we associated the Eurocode equations and added Figure 3 so that we could better link the results and graphs. Also, to improve the quality, we split Figure 6, currently Figure 6, 7 and 8.

 

5º point

Authors:

We appreciate the suggestions of reviewer 2. All changes are presented in the .doc file sent. We completely restructured the article.

Round 2

Reviewer 1 Report

I have revised the corrected version of the manuscript. In the new manuscript, the authors solve my main concerns and improve the quality of the presentation. Accordingly, I recommend the manuscript publication.