Experimental Study on IRV Ramming Artificial Model Ice

Response to Reviewer 1 Comments

1. Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

2. Questions for General Evaluation

Reviewer’s Evaluation

Response and Revisions

Does the introduction provide sufficient background and include all relevant references?

Yes

Thank you for your affirmation

Are all the cited references relevant to the research?

Yes

Thank you for your affirmation

Is the research design appropriate?

Yes

Thank you for your affirmation

Are the methods adequately described?

Yes

Thank you for your affirmation

Are the results clearly presented?

Yes

Thank you for your affirmation

Are the conclusions supported by the results?

Yes

Thank you for your affirmation

3. Point-by-point response to Comments and Suggestions for Authors

The major comments responses are: [Overall the paper is very well written and presents an interesting approach to modelling ship ice interaction using artificial (non-refrigerated) ice. I think the choice of the ice modelling method is one of the more interesting parts of the paper, and I would like to see more discussion on its use. For example, how is the ice introduced into the tank without damage prior to the start of the experiment? Is a fresh sheet of model ice used for each experiment? Are there any specific issues to be aware of, such as health and safety of using the materials etc.]

Response 1: Thank you for pointing this out. We agree with this comment. Therefore, [in the article 2.4 Experimental Setup section, a description of the details of making large model ice sheet and placing the model ice sheet in the tank has been added. The exactly revised this change in manuscript can be found – page 8, paragraph 2, and line 262-272.]

Updated text in the manuscript and has been highlighted. “[The process of preparing and placing the model ice in the tank must be very careful. The preparation and transfer device are designed to be integrated to minimize damage to the model ice. Because the bending strength of the model ice is very low after scaling, the preparation mold must maintain good stiffness to ensure that the model ice sheet does not crack during transportation. First, we prepare small-sized model ice in batches, such as 0.5 m × 1.0 m, and then merge the small-sized model ice into a large-area model ice by pouring it with the same proportion of hot mixture and then cooling it. Of course, large model ice sheet can also be poured at one time. However, it is more efficient to prepare large model ice by merging small-size model ice. A thin plastic film needs to be laid between the model ice and the transfer device so that the model ice and the mold can be separated more easily in the water.]”

The detailed comment responses are:

Comments 2: [Otherwise my comments are of a detailed nature, as given below.

Line 40: It is unlikely that a ship will try to break an iceberg, although it may come into contact with glacial ice fragments.]

Response 2: Thanks for the reminder. We agree with all the detailed nature comments. First, [under normal circumstances, ships will not try to break icebergs. We have changed the icebergs to the glacial ice fragments you described. The exactly revised this change in manuscript can be found – page 1, paragraph 1, and line 38.]

Comments 3: [Table 1: Results "evaluated" in header]

Response 3: Agree. We have modified it in Table 1 to emphasize this point. [The exactly revised this change can be found in the manuscript – page 2, and Table 1.]

Comments 4: [Line 57: Riska studied in detailed the interaction mechanisms]

Response 4: Thank you very much for your grammar guidance. [The exactly revised this change can be found in the manuscript – page 2, paragraph 2, on line 55.]

Comments 5: [Line 58: thick multi-year ice]

Response 5: Thank you very much for your grammar guidance. [The exactly revised this change can be found in the manuscript – page 2, paragraph 2, on line 56.]

Comments 6: [Line 95-98, seems to be a repeat of first sentence of paragraph. Delete.]

Response 6: Thank you very much for your suggestion. Lines 95-98 of the original text have been deleted.

Comments 7: [Prototype displacement must be corrected.]

Response 7: Thank you very much for your correction. The omissions and the errors in Table 2 have been corrected. [The exactly revised this change can be found in the manuscript – page 4, Table 2.]

Comments 8: [Add reference for ITTC procedure.]

Response 8: Thanks for your reminder, we have added a description of ITTC ice making procedures and a comparison with our artificial model ice in the article. [The exactly revised this change can be found in the manuscript – page 6, paragraph 1, on line 192-197.]

Updated text in the manuscript and has been highlighted. “[ITTC model ice preparation procedure is different from the artificial ice preparation procedure in this article. The ITTC [32] ice tank preparation model ice uses cold air to re-duce the temperature of the solution in the tank, allowing it to achieve a phase change from solution to ice, and then controls the mechanical properties of the ice through temperature recovery.]”

Comments 9: [Wrong figure is referenced, should be figure 4.]

Response 9: Thank you for your reminder, it has been corrected in the article. [The exactly revised this change can be found in the manuscript – page 7, paragraph 2, on line 231.]

Comments 10: [Line 243: carriage is common use in English, rather than trailer.]

Response 10: Thank you for providing more professional English guidance. The words have been replaced in the text. [The exactly revised this change can be found in the manuscript –page 7, paragraph 2, on line 239.]

Comments 11: [Line 325: Mention is made of average ramming distances, but no mention is made of repeat experiments. Can the authors clarify this please? Also, the form of the regression lines implies that there is a negative ramming distance obtained from the model at zero speed, which makes no physical sense. Should the equation be forced through the origin, and accept a loss of quality of fit for a more realistic physical relationship? What is the expected uncertainty in the results of the experiments?]

Response 11: Thank you very much for your question, it is very good and very important. [At least three repeated tests were conducted for each initial ramming velocity, so the data points in the graph are the average of multiple repeated tests. The regression lines should indeed pass through the origin and accept the loss of fitting quality. Based on your suggestions, we have redone the regression line graph that conforms to a more realistic physical relationship and replaced it in the original manuscript. For the uncertainty analysis performed on the regression line that does not pass through the zero point, the error in the slope of the regression curve is 0.006416, and 0.03156 after passing through the zero point. Obviously, the fitted regression line through the origin point is better and more consistent with the actual physical meaning. The exactly revised this change can be found in the manuscript – page 10, Figure 7.]

Updated text in the manuscript and has been highlighted. “[Figure 7. Curve of Penetration Distance with Ship Speed Variation]”

Comments 11: [Reference 22 seems to be using the given names of the authors referenced, rather than the family names.]

Response 11: Thank you very much for your reminder. [Reference 22 has been changed to the author’s surname. The exactly revised this change can be found in the manuscript – page 14, Reference 22.]

Updated text in the manuscript and has been highlighted. “[22. Kotilainen M, Suominen M, Kujala P. Rotating ice cusps on ship’s bow shoulder: full-scale study on the cusp sizes and cor-responding peak loads in different ice and operational conditions. Ocean Eng 2019. 189:1–11. https://doi.org/10.1016/j.oceaneng.2019.106280 ]”

4. Response to Comments on the Quality of English Language

Point 1: Overall, well written, but minor corrections required.

Response 1: Thank you very much for your guidance. I have modified the English expressions in the article according to your suggestions.

5. Additional clarifications

[Many thanks to the article editor for their help and the reviewers for their wonderful comments. We believe that a detailed description of the model ice modeling method you are interested in is indeed necessary. After your review and our richness of details can make this article more attractive in terms of experimental research on ship-ice interaction.]

Response to Reviewer 2 Comments

1. Summary

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

2. Questions for General Evaluation

Reviewer’s Evaluation

Response and Revisions

Does the introduction provide sufficient background and include all relevant references?

Yes

Thank you for your affirmation

Are all the cited references relevant to the research?

Yes

Thank you for your affirmation

Is the research design appropriate?

Yes

Thank you for your affirmation

Are the methods adequately described?

Yes

Thank you for your affirmation

Are the results clearly presented?

Can be improved

We have made modifications based on your suggestions, please see the response letter for details

Are the conclusions supported by the results?

Can be improved

We have made modifications based on your suggestions, please see the response letter for details

3. Point-by-point response to Comments and Suggestions for Authors

Comments 1: [It is an interesting paper and important and relevant topic has been studied. I have only few marks for additional work needed before it can be published:]

Response 1: Thank you very much for your wonderful review. This research direction is indeed very interesting and important. Artificial model ice provides good test materials for ice-structure interaction experiments.

Comments 2: [- Please make a graphical drawing of the failure steps shown in Fig 6 and also used in Fig. 8 i.e illustrate by drawings what are the steps in the failure process ( T0 to T5 in Fig 6 and e to f in Fig. 8 ]

Response 1: Thank you very much for your suggestion, it really improves the coherence and readability of the article. We have relabeled the ice destruction process in Figure 6 to strengthen the connection with Figure 8. [The exactly revised this change in manuscript can be found – page 9, Figure 6.]

Comments 3: [- Please describe how is the mean load value determined in Fig 9]

Response 1: Thank you for pointing this out. We agree with this comment. We performed a simple analysis of the payloads, taking the average of their payloads, which is the payload divided by the corresponding time. Taking Figure 8 as an example, for the time-force curve of IRV at a Speed of 0.514 m/s, take the statistical sum of the loads within 24 s -32 s and divide it by the time interval of 8 s.

Comments 4: [- To validate the results can you make a comparison of the load level e.g by comparing some earlier works (like Riska, 1987) i.e take account the different scaling factor and make the results comparable ]

Response 4: Thank you very much for your suggestion, it really works. Riska, 1987 used M.V. Arctic in the study, with a model scale ratio of 40. The length of the M.V. Arctic model is similar to the length of the model used in this study. In fact, the ship length is 209.55 m, and the model length is 5.24 m. The speed range of the IRV ship model studied in this paper is 0.51 - 0.92 m/s, and the maximum ice load range is 340 - 700 N. The speed in the M.V. Arctic ship model test is in the range 0.08 - 0.45 m/s, and the maximum ice load range is 300 - 800 N, the load levels of the two are of the same magnitude and not much different, and the load curves have the same trend.

4. Response to Comments on the Quality of English Language

Point 1: English language fine. No issues detected.

Response 1: Thank you for your affirmation.

5. Additional clarifications

[Many thanks to the article editor for their help and the reviewers for their wonderful comments. We believe that a detailed description of the model ice modeling method you are interested in is indeed necessary. After your review and our richness of details can make this article more attractive in terms of experimental research on ship-ice interaction.]