Design of and Experiment on a Cleaning Mechanism of the Pneumatic Single Seed Metering Device for Coated Hybrid Rice
Round 1
Reviewer 1 Report
Manuscript “Design and Experiment of Cleaning Mechanism of Pneumatic 2 Single Seed Metering Device for Coated Hybrid Rice”
This manuscript will be interesting for scientists, who develop and research the seed-metering device of a seeder. Also, these scientific results will have practical application. In order to improve the manuscript, I suggest the following corrections:
1. The article states that “Existing studies have found that the seeding accuracy of the pneumatic seed metering device is not only related to the seed suction performance, but its seed cleaning performance is also one of the key factors affecting the seed metering performance.” (p. 2, lines 51-54). It is necessary to indicate the source where this existing studies can be verified.
2. The article states the following:
“…Lai designed a six-row air-blowing centralized precision seed-metering device, … and explored the best combination of parameters [9]” (p. 2, lines 59-62);
“…Wang designed a vacuum central drum seed-metering device, … , the combination design has certain reference for improving the sowing precision of hybrid rice seeds [10].” (p. 2, lines 62-65);
“…Wang designed a wheel seed-cleaning mechanism, which improved the seed cleaning performance of the corn seed metering device during high-speed [11].” (p. 2, lines 67-69);
“…Xiong designed a sowing device … [12].” (p. 2, lines 70-74);
“…Ding carried out a saw-tooth seed cleaning mechanism … [13].” (p. 2, lines 76-78).
It is incorrect to state that these devices were designed only by Lai, Wang, Wang, Xiong and Ding. Because, there are many authors of the articles [9-13]. It is recommended to remove the following last name Lai, Wang, Wang, Xiong and Ding, and leave only links to articles in which devices are proposed.
3. In the text of the article, where the positions in Fig. 1 are explained (p. 2, lines 92-93), under position 3 there is a seed cleaning mechanism. In the explanation to Fig. 1, this position is called cleaning device (p. 3, line 97). It is necessary that the positions are named the same. Similar corrections must be made for position 5 (a seed metering shell – seed chamber shell).
4. It is necessary to write the word “Through” with a small letter (p. 3, line 107). In the article text, it is often found that the first word of the sentence is written with a small letter.
5. Semicolon must precede “… (3) Both rice seeds are …” (p. 3, line 124).
6. In Fig. 3, the vector of force Q is directed parallel to the plane of the suction cup. In my opinion, such a direction of the vector of force Q is not justified. The force Q depends on the forces J and G, which depend on the mass of the rice seed and the rotation speed ω. So, the direction of the force Q will depend on the value of the forces J and G. Therefore, force balance condition (1) is incorrect. It is appropriate to write condition (1) in the form:
P1·(d/2) + G·C ≥ J·(d/2),
where C is the distance from the action line of force G to the edge of suction cup (in the proposed Figure it is point A).
7. The article states that “… G is the rice seed weight, kg …” (p. 5, line 153). But G is the seed gravity and the force unit is H.
8. It is not clear as a result of which mathematical operations the right-hand side (С|G – J|) of condition (4) was obtained. In my opinion, it is necessary to change conditions (3) and (4) taking into account the recommendations made by me in point 6.
9. The article states the following “… the coating material increases the surface area of the rice seeds and improves the surface characteristics of the rice seeds …” (p. 10, lines 281-282). It is necessary to indicate which surface characteristics of the rice seeds were improved and how this improved the seed cleaning effect of the seed metering device.
10. In article section 4.1.1, it is also necessary to indicate with what substance the rice seeds used for research were coated.
11. In article section 4.2, it is necessary to present the regression model for the qualified index, missing index, multiple index, which were obtained by the results of experimental data processing.
Comments for author File: 
Comments.pdf
Author Response
Thank you very much for taking the time to review this manuscript. I really appreciate all your comments and suggestions! Please find my itemized responses in the attachment and my revisions/corrections in the resubmission.
Author Response File: Author Response.pdf
Reviewer 2 Report
The manuscript deals with theoretical and practical studies of the design of a rice seed cleaning and separation device in a precision pneumatic seeder. Numerical parameter studies (CFD) simulating airflow through the nozzles were carried out. On the model of the device fixed on the test bench, tests were performed on the efficiency of the seed cleaning device, and statistical analysis of the obtained results was carried out. The results are illustrated by graphs. The manuscript, in my opinion, is suitable for publication in the scientific journal Agriculture but needs some additions.
I comment on the Discussion chapter, where there is a lack of reference to previously cited scientific papers and other technical solutions of similar effect. I think that the authors of the manuscript should complete this chapter, taking into account the results of their own and other researchers, even if they do not apply to rice grains but to seeds of other plant species.
Author Response
Thank you very much for taking the time to review this manuscript. I really appreciate all your comments and suggestions! Please find my itemized responses in the attachment and my revisions/corrections in the resubmission.Author Response File: 
Author Response.docx
Round 2
Reviewer 1 Report
The authors of the article took into account most of my recommendations. But, in order to improve the manuscript, I suggest the following corrections:
1. In my opinion, Fig. 3b is incorrect, it must be turned so that the direction of forces on it corresponds to their direction in Fig. 3a. If the seed location (Fig. 3a) is analyzed, then condition (1) is incorrect. In this case, the condition will be as following:
P1·(d/2) + G·C ≥ J·(d/2),
where C is the distance from the action line of force G to the edge of suction cup.
2. In the case when the angle α is 180 degree (Figure), condition (4) will be as following:
P1 ≥ J – G.
To determine the minimum required value of the force P1, it is necessary to know the rice seed mass (it is recommended to specify the average mass of a coated rice seeds in the article) and the disc rotation speed ω.
Accordingly, there is no need to present equation (2) for determining the force Q and condition (3) in the text of the article.
3. In article section 4.2, only the regression model for the qualified index and missing index are added. But the regression model for the multiple index must be added, which was obtained by the results of experimental data processing.
Comments for author File: Comments.pdf
Author Response
I have put the reply in the attachment, thank you for viewing.
Author Response File: Author Response.pdf
