Design and Experimental Research on Centralized Lubrication and Waste Oil Recovery System for Wind Turbines

Round 1

Reviewer 1 Report

The manuscript deals with the design and experimental research on centralized lubrication and waste oil recovery system for wind turbines.

 

The overall quality of the work is good and it is recommended that it be accepted for publication. However, the results and conclusions can be improved. Better quality images are also recommended.

Author Response

Dear Reviewer,

We would like to thank you for your careful reading, helpful comments, and constructive suggestions, which has significantly improved the presentation of our manuscript. We have carefully considered all comments and revised our manuscript accordingly. We look forward to your reply. Thanks again!

Point 1: The overall quality of the work is good and it is recommended that it be accepted for publication. However, the results and conclusions can be improved. Better quality images are also recommended.

Response 1: We gratefully appreciate your valuable suggestion. We have refined the results and conclusions section

 

Point 2: English language and style are fine/minor spell check required

Response 2: Thank you for your above suggestions. We carefully examined the article, made full-text changes, and changed some spelling errors and non-English words.

Author Response File: Author Response.docx

Reviewer 2 Report

Remove the personal pronouns in the manuscript (row 28 "..of my country's..."). There are a lot of spelling mistakes in the manuscript. Please revise or rewrite according to the exact English (American or Britain) grammar style.

Secondly, I do not exactly understand the literature review following the designated problems for the study. How are you matching the problems of wind turbine lubrication (e.g., blockage, bearing cavity, blockage, bearing seal leakage, etc. - Row 33-36) with various authors? Please explain what message you are trying to send. Just saying in a sentence per sentence, what have they designed, or how are they relating or resolving the problem? From 47-57 rows, what are you explaining by citing the method of other authors? I still do not get the message you are trying to send with your paper.

In 58-66, you are already claiming that by optimization of supply mode, the blockage of LS (lubrication system) is avoided. I think that the hierarchical structure of sentences and introductions should be expanded and more thoughtfully expressed. Then you say you are focusing on waste oil removal, simulation, and then building a test platform... Please rewrite the sentences in a more meaningful way.

"The internal structure and maintenance environment of the wind turbine determine(determines? - spelling mistake?) that centralized lubrication is generally selected for lubrication" what does this even mean? Do you mean that difficulties in maintaining the wind turbines are more prone to conducting centralized lubrication systems? Hard to maintain and access different parts of the system, i.e., components that need to be lubricated? ...centralized lubrication is generally selected for lubrication... What??

Where did you collect your figures? Did you draw it yourself or request a free copyright? It can be seen that figure 3 (which you in the text call fig2a, fig2b, fig2c) is used from other websites and lacks proper citation (http://www.autolgroup.com/solution/wind-power/).

In eq 1-5, what are you trying to explain? What is a "model"? What are separate SP, and how are they the increment of considering diff of volumetric change per p/t? Can you explain more about air quality? Where did you run a simulation? What is the clear outcome of the research? How does your research fit into existing research within the sphere of maintenance and lubrication? How does it fit within existing research on waste oil recovery? How does it contribute to the literature? How do you portray the impact of your research, let's say, in Sustainability Maintenance/Manufacturing or in Energy-Based Maintenance research? How does your list of references emphasise the state-of-the-art significance of your research? How does it impact society? Where is the discussion section to elaborate on that? What are the implications of the research? What is the contribution to the literature? What is future research? 

 

Author Response

Dear Reviewer,

We would like to thank you for your careful reading, helpful comments, and constructive suggestions, which has significantly improved the presentation of our manuscript. We have carefully considered all comments and revised our manuscript accordingly. We look forward to your reply. Thanks again!

Point 1: Remove the personal pronouns in the manuscript (row 28 "..of my country's..."). There are a lot of spelling mistakes in the manuscript. Please revise or rewrite according to the exact English (American or Britain) grammar style.

Response 1: Thank you for your above suggestions. We carefully examined the article, made full-text changes, and changed some spelling errors and non-English words.

 

Point 2: Secondly, I do not exactly understand the literature review following the designated problems for the study. How are you matching the problems of wind turbine lubrication (e.g., blockage, bearing cavity, blockage, bearing seal leakage, etc. - Row 33-36) with various authors? Please explain what message you are trying to send. Just saying in a sentence per sentence, what have they designed, or how are they relating or resolving the problem? From 47-57 rows, what are you explaining by citing the method of other authors? I still do not get the message you are trying to send with your paper.

Response 2: Thank you for your above suggestions. According to your suggestion, we will improve this part and describe the results of these scholars in detail.

 

Point 3: In 58-66, you are already claiming that by optimization of supply mode, the blockage of LS (lubrication system) is avoided. I think that the hierarchical structure of sentences and introductions should be expanded and more thoughtfully expressed. Then you say you are focusing on waste oil removal, simulation, and then building a test platform... Please rewrite the sentences in a more meaningful way.

Response 3: According to your suggestion, we will lubrication and waste oil recovery two parts separately summarized, more comprehensive expression.

 

Point 4: "The internal structure and maintenance environment of the wind turbine determine(determines? - spelling mistake?) that centralized lubrication is generally selected for lubrication" what does this even mean? Do you mean that difficulties in maintaining the wind turbines are more prone to conducting centralized lubrication systems? Hard to maintain and access different parts of the system, i.e., components that need to be lubricated? ...centralized lubrication is generally selected for lubrication... What??

Response 4: Thank you very much for your suggestion, we have revised the spelling error and explained in detail the phrase ' the internal structure and maintenance environment of wind turbines determine that centralized lubrication is usually chosen for lubrication '.

 

Point 5: Where did you collect your figures? Did you draw it yourself or request a free copyright? It can be seen that figure 3 (which you in the text call fig2a, fig2b, fig2c) is used from other websites and lacks proper citation (http://www.autolgroup.com/solution/wind-power/).

Response 5: Your suggestion is very useful to us. This picture is provided by the third author Zhao, who is the general manager of the company on the website you sent me. Image use is permitted and there is no copyright dispute. However, editor Danduka thought that Zhao 's contribution was not enough, and asked me to delete the third author. Your suggestion is highly appreciated, and we have added image references to the paper.

 

Point 6: In eq 1-5, what are you trying to explain? What is a "model"? What are separate SP, and how are they the increment of considering diff of volumetric change per p/t? Can you explain more about air quality? Where did you run a simulation? What is the clear outcome of the research? How does your research fit into existing research within the sphere of maintenance and lubrication? How does it fit within existing research on waste oil recovery? How does it contribute to the literature?

Response 6: Thank you for your above suggestions. The formula 1-5 is used to calculate the vacuum pressure. Due to the consideration of the structure of the paper, the initial vacuum grease content was split into 2.2.1 and 3.1.1 parts. There were some errors in the expression, and we optimized the expression.; SP represents the amount of gas discharged by the vacuum system in the bearing cavity per unit time ; We improve the content of the vacuum calculation part and added more descriptions of air quality in section 2.2.1. we use FLUENT to complete the numerical simulation ; the research results of this part and the contribution of the article are improved in section 3.1.1 ;

Author Response File: Author Response.docx

Reviewer 3 Report

In general the figures have low resolution, figure 1,3, 4,5,8 for example are impossible to read.

Figure 11 has a mistake in formating

There are any statistical validation of the output data? I saw no measurement of uncertanties, no analysis of variance, not even error bars in most of the graphs. How can I trust the results? How can I draw conclusions of this data if it does not present any statistical analysis? 

The aforementioned problems must be adressed, or the paper will not have scentifical significance.

Author Response

Dear Reviewer,

We would like to thank you for your careful reading, helpful comments, and constructive suggestions, which has significantly improved the presentation of our manuscript. We have carefully considered all comments and revised our manuscript accordingly. We look forward to your reply. Thanks again!

Point 1: In general the figures have low resolution, figure 1,3, 4,5,8 for example are impossible to read.

Response 1: We gratefully appreciate your valuable suggestion. We have replaced these pictures you said with more explicit ones.

 

Point 2: Figure 11 has a mistake in formatting.

Response 2: Thank you for your above suggestions. Indeed this mistake we should not make, we have modified the image format qualified.

 

Point 3: There are any statistical validation of the output data? I saw no measurement of uncertanties, no analysis of variance, not even error bars in most of the graphs. How can I trust the results? How can I draw conclusions of this data if it does not present any statistical analysis?

Response 3: We gratefully appreciate your valuable suggestion. We have refined the results and conclusions section. We added the overall description results in the analysis part of the test results, added error lines to each figure, and calculated the uncertainty. We also analyze the variance of vacuum changes. After analysis, our test data is highly reliable and can fully prove our test results.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Dear authors,

the second paragraph that you improved is now in past and present tense (e.g., you start with "currently, major problems...etc. etc.," then explain the problems within articles of authors "Zhou [8] designed.....etc... which improved...". Please rephrase that. Maintain the present or past tense, whatever you want; don't switch back and forth.

All figures should be replaced with more visible ones with Fonts matching the text font (Times new roman). Remove frames from figure 9 and depict lines in higher quality. Depict labels for all axis on all figures; for instance, in figure 9, what is the axis? if you say y-axis oil pressure, what is "oil pressure/MPa"? Do you mean Oil Pressure [MPa] ? Table 2. General description results... Do you mean Descriptive statistics? What are your presenting variables of Kurtosis and Skewness? Or any other outside of stdev, mean and var? Are you using that for the statistical test? What is the standard error in an experiment? How does that affect the sample size and results obtained? As we are considering the test, in table 4, you've depicted the significance level using ANOVA (as you've stated, "one-way analysis of the variance" where are the rest of the test statistics? And significance levels, if not significant, what are you providing asterisks *** of levels of significance? Stdev measure? If you have an equal sample size, did you use a posthoc test (e.g., Tukey, Bonferroni...)? Homogeneity with means plot can be good to represent the results in addition to Welch and Brown. What exactly homogeneity test? Levene? What is the measure? There is too much inconsistency in presenting the results obtained from statistical analysis. If you are measuring the statistical effect of the experiment, is this an appropriate way to represent the results? You have 2 times table 4 with different results...

Author Response

Dear Reviewer,

 

We would like to thank you for your careful reading, helpful comments, and constructive suggestions, which has significantly improved the presentation of our manuscript. We have carefully considered all comments and revised our manuscript accordingly. This modification is highlighted in yellow. We look forward to your reply. Thanks again!

 

Point 1: The second paragraph that you improved is now in past and present tense (e.g., you start with "currently, major problems...etc. etc.," then explain the problems within articles of authors "Zhou [8] designed.....etc... which improved...". Please rephrase that. Maintain the present or past tense, whatever you want; don't switch back and forth

Response 1: We gratefully appreciate your valuable suggestion. The second paragraph has been changed as a whole and the past tense is adopted.

 

Point 2: All figures should be replaced with more visible ones with Fonts matching the text font (Times new roman). Remove frames from figure 9 and depict lines in higher quality. Depict labels for all axis on all figures; for instance, in figure 9, what is the axis? if you say y-axis oil pressure, what is "oil pressure/MPa"? Do you mean Oil Pressure [MPa] ?

Response 2: Thank you for your above suggestions. We have changed the image clarity of Figures 9-12 and replaced the font with the correct font. At the same time, the frame was deleted and the coordinate unit was changed.

 

Point 3: Table 2. General description results... Do you mean Descriptive statistics? What are your presenting variables of Kurtosis and Skewness? Or any other outside of stdev, mean and var? Are you using that for the statistical test? What is the standard error in an experiment? How does that affect the sample size and results obtained?

Response 3: According to your suggestion, we revised the expression of ' descriptive statistics '. In Table 2, kurtosis and skewness are used to represent the variables before and after the test, which are used to observe whether the data is normal distribution. The standard error of the test is shown in the figure as an error line ( required by another reviewer ). We added additional explanation of error bars at the end of the experimental section of the paper.

 

Point 4: As we are considering the test, in table 4, you've depicted the significance level using ANOVA (as you've stated, "one-way analysis of the variance" where are the rest of the test statistics? And significance levels, if not significant, what are you providing asterisks *** of levels of significance? Stdev measure? If you have an equal sample size, did you use a posthoc test (e.g., Tukey, Bonferroni...)? Homogeneity with means plot can be good to represent the results in addition to Welch and Brown. What exactly homogeneity test? Levene? What is the measure?

Response 4: According to your question, we carefully checked this part. The main purpose of ANOVA in this paper is to prove that there is no significant difference in vacuum (according to the analysis results, it is indeed not significant). If not significant(P>0.05), there is no asterisk *. Post hoc multiple comparisons(post hoc test) generally analyze the specific differences between variables when there are significant differences after analysis of variance. In our analysis, there was no significant difference in vacuum degree before and after the test, so post hoc multiple comparisons was not performed( when P>0.05, post-hoc multiple comparisons are generally not done). Based on your suggestions, we added a mean plot of the vacuum degree and analyzed it. The F-test is used for homogeneity of variance test.

 

Point 5: There is too much inconsistency in presenting the results obtained from statistical analysis. If you are measuring the statistical effect of the experiment, is this an appropriate way to represent the results? You have 2 times table 4 with different results...

Response 5: We carefully checked the paper, and the calculations matched the analysis and did not find "inconsistency" In the original version, we did not analyze the data, of course, this is our defect. Descriptive statistics, ANVOVA, and error bars were all added at the request of another reviewer. Due to our mistakes, there have been two Table 4, the second ' Table 4 ' is actually ' Table 5 '. Table 4 shows the homogeneity test of variance and Table 5 shows the results of the analysis of variance.

Author Response File: Author Response.docx

Reviewer 3 Report

The article has undergone substantial improvements and can be accepted in its current form.

Author Response

Dear Reviewer,

Thank you very much for your careful review and comments again. Your recognition will help us to publish our papers. Thanks again!

Author Response File: Author Response.docx