Design Improvement of a Viscous-Spring Damper for Controlling Torsional Vibration in a Propulsion Shafting System with an Engine Acceleration Problem

Round 1

Reviewer 1 Report

The work deals with a topic that affects very large ships built only by Asian shipyards. It is tackled with a scientific and rigorous approach. The physical phenomena underlying the proposed system are well described, however, the novelty of the study is quite poor.

The same authors produced many of the references considered and some of them are in Korean, certainly difficult to consult by an average reader. Bibliographic analysis could be deepened on databases of wider diffusion.

The claim that fuel oil is very expensive must certainly be reviewed, given that especially with reference to the HFO (Heavy Fuel Oil) used in the 2-stroke engines considered, these are years that have reached historic lows (also in low Sulphur Mixture). Moreover, the authors could add a few more considerations to better describe the "de-rating" of 2 stroke engines and its consequences on the operation.

In conclusions, figures, being the core of the paper, must be improved in quality and dimensions, and rearranged in order to better follow their description in the text.

Author Response

 

First of all, i would like to give a many thanks for your effort to review this submitted paper. After reviewing your kind comments on my manuscript, i revised it with red colors according to your comments. Please see this revised manuscript as shown the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The paper discusses the vibration analysis of energy-efficient long-stroke engine and the implementation of the viscous damping system and optimization of its parameters.

The paper is written well and easy to follow. The authors provided extensive background on the theory and discussed the 

Couple suggestions:

1. Figure 1 and Figure 3 show two labels indicating two cases. However, Case 1 and Case 2 in each figure are different. It might be better to use different wording not to confuse the reader.
2. On page 5, it's stated that "The following is the equation of motion for the vibration system.". However, there are 6 equations are provided. Please provide what each variable mean.
3. Equations 4-6 are written twice

Author Response

First of all, i would like to give a many thanks for your effort to review this submitted paper. After reviewing your kind comments on my manuscript, i revised it with red colors according to your comments. Please see this revised manuscript as shown the attachment.

Author Response File: Author Response.pdf