Hydrodynamics and Wake Flow Analysis of a Floating Twin-Rotor Horizontal Axis Tidal Current Turbine in Roll Motion

Round 1

Reviewer 1 Report

The authors presented a numerical study on the Hydrodynamics and wake flow analysis of a floating twin-rotor horizontal axis tidal current turbine in roll motion

The paper is generally well prepared, and the results are very interesting. The paper can be accepted for publication after addressing the following points:

The main quantitative results are to be mentioned in the abstract.

The novelty of the paper is to be clearly stated.

What is the interest of presenting the ‘’ Basic theory’’ section?

The dimensions of the computational domain are to be justified.

The used turbulence model is to be justified.

What is the range of Reynold number corresponding to the considered cases?

What is the convergence criterion?

A Grid sensitivity test is to be performed.

Information about the characteristics of the used computer and computational time are to be provided.

In addition to the presented quantitative validation, a qualitative verification (flow structure or velocity field for example) of the numerical model is to be performed by comparing with previously published numerical results.

It will be interesting to present the streamlines for a better understanding of the flow structure.

The paper is to be checked for misprints and grammatical mistakes

 

The paper is to be checked for misprints and grammatical mistakes

 

Author Response

Thank you very much for your review. Your valuable suggestions are of utmost importance to me. I have compiled the questions and answers into a Word document for your reference. Please take a look at your convenience.

Author Response File: Author Response.pdf

Reviewer 2 Report

The paper is a study to analyze the effect of roll motion and TSR of a dual tidal current turbine on turbine performance. The CP and CT were compared while varying the rolling period and TSR, and were analyzed based on the velocity and vorticity contour distribution. The research results can be referenced as basic data for developing a floating tidal current turbine in the future. Modifications are recommended based on the review comments below.

 

1. Page 5, ‘2.2.3. Mesh’

Based on the results of the grid dependence test, the optimal grid should be determined, and information about y+ should be added.

 

2. Page 11, 3.4. ‘Effects of roll period and TSR on the wake of the turbine'

Wake recovery needs to be defined. What is the criterion for evaluating wake recovery numerically? And It also needed to define the average recovery of wake velocity in Fig. 11.

 

3. Page 13, last paragraph

A detailed explanation is required to understand the contents of the paragraph. It needed to define the criteria of ‘vortices persist’ 

 

4. Page 14, last paragraph

What is the criterion for determining’ faster wake recovery’ in Fig.12? Fig 12(c.e) was classified as a faster wake recovery group, but in Fig 11(b), T=0.75s, TSR=5 and T=1.5s, TSR=8 show excellent velocity recovery.

 

Author Response

Thank you very much for your review. Your valuable suggestions are of utmost importance to me. I have compiled the questions and answers into a Word document for your reference. Please take a look at your convenience.

Author Response File: Author Response.pdf

Reviewer 3 Report

The presented work is beneficial for the Journal audience. However, it needs major revisions before its acceptance. My detailed comments/suggestions are appended below:

1.      Although, the abstract written well but some further quantitative results should be included to entertain the Journal audience at a glance.

2.      There are many abbreviations used. Add full name instead of abbreviations or at least one time cite the word completely.

4.      The introduction section must contains a paragraph describing that what have been done previously, what are the potential research gap and why the authors focused on the present problem. What is the main novelty of the current work? There are many other effective mathematical schemes available in literature. Why the authors focused on this scheme. For instance, see Case studies in thermal engineering v. 48, ID:103130 ; ACS Omega 2023, 8,22, 19926-19938 and AIMS Mathematics 2023, 8(7), 15932-15949.

 

5.      Why the authors updated the model using these physical parameters and why selected such parametric ranges. Is there any physical reason behind this? It should be addressed clearly in the revised manuscript.

6.      Model formulation section should be improved in the view of imposed assumptions because this section is very important for the audience to know about the study at a glance.

9.      The references list lack some important information about the published data. It should be improved by adding all the necessary information like volume, issue, page number or in the case where page number is unavailable, the doi must be added in that case.

 

1.  Acceptance of the article is subject to the responses of each of the above comment/suggestion.

The language needs moderate improvement

Author Response

Thank you very much for your review. Your valuable suggestions are of utmost importance to me. I have compiled the questions and answers into a Word document for your reference. Please take a look at your convenience.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

This revised paper is recommended to publish in the JMSE journal.