Optimization of the Energy Capture Performance of the Lift-Drag Hybrid Vertical-Axis Wind Turbine Based on the Taguchi Experimental Method and CFD Simulation
Round 1
Reviewer 1 Report
The wind turbine with combined lift and drag can improve the wind turbine power factor, which has a strong practical significance.
1. The references are supplemented with the results of studies by related authors in the last two years to better demonstrate the novelty of the work in this paper.
2. The cloud diagram in Figure 12 can show richer details, such as the unit of pressure.
Author Response
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Reviewer 2 Report
Based on the analysis of the interaction between wind turbines and fluids, this article uses a combination of CFD and Taguchi experiments to optimize the lift-drag hybrid vertical axis wind turbine. Finally, the simulation results are experimentally verified. The overall idea of the article is excellent, and the structure of the paper is good and clear. It is very comfortable and interesting to read. However, there are some problems:
1. In line 130 of the article, there should be a gap between variables and words.
2. The title bar of Table 2 is not clearly labeled and has formatting errors.
3. Abstract (and further). "16.2%". There is no sense in such accuracy because there are a lot of assumptions of the model that will never allow more than two non-zero digits to be accurate. Similarly, in the experiment, 5% accuracy is supposed to be high enough. It is best to round to an integer here and use the same precision everywhere else.
4. In some places in the paper, the term "aerodynamic moment" is used, and in others, the term "aerodynamic torque" is used. It is better to unify. The "torque" seems preferable.
5. In the third section of the article. "wind-induced rotating wind turbine" ---> wind-induced rotation of VAWT or wind-induced motion of VAWT (not the device itself is wind-induced, but its rotational motion).
6. In the reference, the ref [21] needs to translate Chinese into English.
Author Response
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Reviewer 3 Report
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Reviewer 4 Report
This work focus on the optimization of the energy capture performance of the lift-drag hybrid vertical-axis wind turbine. Analyses of the effects of pitch angle, installation angle, overlap ratio, and diameter ratio are implemented based on Taguchi experimental method and CFD simulation. This manuscript helps improve the design of hybrid wind turbines with higher energy capture efficiency. Meanwhile, a number of substantive issues are elaborated on below, all aimed at improving the work.
1. This manuscript does not comprehensively introduce the published studies. Some important and closely-related publications are missed.
2. It is not convincing for the validation of the model. Detailed comparison and verification with the experimental results are suggested to add.
3. Please elaborate on how to evaluate the degree of influence of each parameter.
4. Some mistakes should be modified, such as kV not KV.
5. The writing needs to improve. There are minor errors and grammar mistakes. Please revise them.
The writing needs to improve. There are minor errors and grammar mistakes. Please revise them.
Author Response
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Round 2
Reviewer 3 Report
I have checked throuh all the suggestioned points mentioned before and most of them have been revised. However, there are two important questions shown below that I looked up all the paper but couldn't find any updates.
1. Chapter-4 Method Verification: (not answering!)
In your simulation model, the input variables contain varying Tip Speed Ratio corresponding to the inlet flow speed and rotational speed. The torque analysis in this paper is reasonable for Savonius drag-dominant blade. However, the Darrieus relying on lift force to rotate has different mechanism and usually through the method of Disk Actuator or Blade Element Theory to get the aerofoil’s volume force and torque. It is suggested to clarify how you treat the hybrid turbine simulation under different torque situations.
2. Result and discussion of Figure-10 and Figure-11:
In this simulation, the status of negative torque exaggerates for the hybrid turbine due to its high acceleration. However, the results show that the traditional pure lift turbines have relatively low Cp ranges (below 3%), where 15% for Savonius and 35% is for Darrieus is a common range. This underestimation should be clarified.
(Not answer too!!)
NA
Author Response
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Reviewer 4 Report
The Authors have addressed my comments and questions. I don't have other comments or questions.
There is still space to improve in the paper writing.
Author Response
Dear Reviewer:
Thank you very much for your suggestions on our manuscript. By modifying the corresponding sections, the logic and expression of the article have been greatly improved. We are well aware that our English writing needs improvement, but due to time constraints, we cannot make further modifications. We apologize for this and will improve our skills in this area in future work. We look forward to working with you in the future.
Sincerely,
Jin-tao ZHANG, Chao WANG, Wen-hao LIU, Jian-yang ZHU, Yang-yang YAN, Hui ZHAO
Round 3
Reviewer 3 Report
see attached file!
Comments for author File: Comments.pdf
Author Response
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