Development and Numerical Simulation of a Precision Strip-Hole Layered Fertilization Subsoiler While Sowing Maize

Round 1

Reviewer 1 Report

Dear authors, please find in the pdf file the broad and specific comments to your paper.

Comments for author File: Comments.pdf

Author Response

Dear peer reviewers and editors

Hello! Thank you very much for your professional and wise comments on this article. According to the experts' questions and opinions, the author gives a detailed explanation in the form of one question and one answer, and marks the manuscript with red font in the corresponding position, as follows:

QUESTION1: The aim of the paper is to analyze and optimize the main parameters of the fertilizer application. As stated in the abstract the results achieved are the basis for a new way of fertilizer application methods and for the design of application machinery. However, it is not really clear if the machinery described is completely new as result of the investigation. It seems that the main component affected by the investigation is the hole wheel. In general, it is better to clarify if the whole machine is a new prototype or if, starting from a machine already on the market, some new components are introduced and mechanically controlled for optimizing the fertilization process.

RE: Thank you very much for your valuable comments. Through reading and consulting the literature, at present, the main method of fertilizer application for maize mechanization is strip fertilization, the hole application is also only a single layer. In this paper, I propose a fertilizer application method that combines strip and hole application, with the base fertilizer applied in strips, the additional fertilizer and substrate fertilizer applied in holes. The base fertilizer, additional fertilizer and substrate fertilizer applied into the soil at one time. The precision strip-hole layered fertilizer subsoiler was designed, which can apply fertilizer to the soil in quantitative and fixed positions according to the fertilizer requirements of the maize growth cycle and the length of the root system in each period.

QUESTION2: According to my understanding, the main parameters are related to the design of the hole wheel. If so, in materials and method section it should be emphasized.

RE: Thanks to the reviewers for their valuable comments. As suggested by the reviewers, the main parameters are related to the design of the hole wheel. The parameters of the hole wheel affect the effectiveness of the fertilizer application. For this reason, I have carried out a detailed theoretical analysis of the various parameters of the hole wheel in sections 2.2.3 - 2.2.5 to arrive at a range of parameters suitable for this application requirement.

QUESTION3: Moreover, in section 2.2.2, the precision strip-hole layered fertilization subsoiler is described. However, it is not clear if it is a completely new unit.

RE: Thank you very much for your valuable comments. Through reading and consulting the literature, as there is currently no relevant machinery for the combination of strip and hole application. The precision strip-hole layered fertilization subsoiler is designed to meet a new way of fertilizing that I have proposed.

QUESTION4: It has a motor which seems to be mechanically engaged with the hole wheel. If so, some details on the way of controlling it and how it is affected by the design parameter of the hole wheel should be reported.

RE: Thank you very much for your valuable comments. The tractor drives the no-till planter forward and the Beidou Navigation receiver receives the forward speed signal from the tractor and transmits it to the communication controller, which then processes and controls the motor speed. The design parameter of the hole wheel has no effect on the motor. I have amended it and marked it in red.

QUESTION5: Section 2.2.3 describes the analytical method for investigating the design parameters of the hole wheel. For clarification a specific figure representing only the design parameters (e.g. AFT, AUF, etc.) should be introduced. In this section and within the paper the hole wheel seems to be referred also with other terms (e.g. orifice wheel, bore wheel, etc.). If it is always the same component it is better to use a uniform language to avoid confusion in the reader.

RE: Thank you very much for your valuable comments. Through reading and consulting the literature, I have modified the language to use uniformity and marked it in red.

QUESTION6: The number of section 2.2.4 is repeated twice. Both sections numbered as 2.2.4 report an analytical approach to describe the interaction between particles and the surfaces of the hole wheel during the distribution process. However, numerical values are not really applied. The analysis is just qualitative, to show the foreseen behavior of the particles according to the main parameters selected for the investigation. Moreover, it is not clear how the range of values assumed for some parameters (e.g. angles, angular velocity, etc.) are set.

RE: Thank you very much for your valuable comments. The number of section 2.2.4 has been revised, and your suggestion that 2.2.4 is only a qualitative analysis, I have analyzed the fertilizer filling and discharging process to provide a numerical reference for the design of the type of bore wheel, and also obtained a key parameter in the article, the angle at which the fertilizer is unloaded, and I think it is necessary to analyze them. As described in section 2.25, the angular speed is based on the tractor's forward speed and matching the size of the bore wheel, and the angle is based on the analysis in sections 2.2.3 - 2.2.5.

QUESTION7: Section 4 Discussion, seems to be not really related to section 3. Just in the first paragraph there is some reference to the parameters used in section 3. In this section should be reported the deep analysis of the results achieved in order to better understand how they affect the design of the machine and the fertilization process.

Then it is possible to illustrate how the optimized fertilization process may affect the growth of maize (as described in lines 437 – 446).

RE: Thank you very much for your valuable comments. In this section, the results I have obtained are analyzed in depth, the effect of forward speed for on FDT and what they produce and the effect of forward speed, AUF, AFT on FADSC and what produces the effect are analyzed and I have marked the modified ones in red.

QUESTION8: Finally, section 5 Conclusion summarizes the main results achieved. However, it is just a bullet point list reporting the main steps of the investigation. There are no consideration on the impact of the research activity and its main focus related to a new prototype of the machine (or at least of some components) based on the optimum parameters obtained from the analysis. It is useful to clarify which are the perspectives and how the results may affect the design of the machine (as stated in the abstract) or the way of the operator has to perform the fertilization process by means of the present machines already in use. Some considerations on future works or the perspective of the results achieved on the production of fertilization machinery or on the fertilization process may be useful.

RE: Thank you very much for your valuable comments. Based on your comments, I have rearranged and revised my conclusions in section 5 , Based on your comments, I have rearranged and revised my conclusions in part 5, forward speed, AUF and AFT will have an effect on FDT and FADSC, I have stated the relationship between them and the effect FDT and FADSC will have on crop growth in the conclusion and marked them in red .

QUESTION10: Line 24 and in the whole paper: between the numerical value and the unit add a space. Line 59: change “;” with “.”.

RE: Thank you very much for your valuable comments. I have amended it according to your comments and marked it in red.

QUESTION11: Line 108: change “Hole” with “hole”.

RE: Thank you very much for your valuable comments. I have amended it according to your comments and marked it in red.

QUESTION12: Line 111: the “filling stage” should refer to “grouting period” in figure 1. It is better to align wording in the text with the keys used in figure 1.

RE: Thank you very much for your valuable comments. I have amended it according to your comments and marked it in red.

QUESTION13: Figure 1: an additional top view may clarify what described in lines 105 – 107.

RE: Thank you very much for your valuable comments. Based on your comments I have added the additional left view.

QUESTION14: Line 118 and figure 12a: what is the function of Beidou navigation receiver? Is it necessary for the investigation reported in the paper? It seems that its function is not related to the research activity. Maybe the tractor used for in field tests was equipped with it for agriculture 4.0. Clarification is needed.

RE: Thank you very much for your valuable comments. The tractor drives the no-till planter forward and the Beidou Navigation receiver receives the forward speed signal from the tractor and transmits it to the communication controller, which then processes and controls the motor speed. Beidou Navigation receiver receives tractor speed signals to control motor speed during field tests. Based on your comments I have added the clarification and marked it in red.

QUESTION15: Line 126: “before sowing” is repeated twice.

RE: Thank you very much for your valuable comments. I have removed the duplicate "before sowing".

QUESTION16: “soil divider” is not reproduced in figure 3.

RE: Thank you very much for your valuable comments. The role of the subsoiler in figure 3 is to deeply loosen and divide the soil.

QUESTION17: fertilizer wheel should be the hole wheel. Uniform language is appreciated (see broad comment).

RE: Thank you very much for your valuable comments. I have replaced "fertilizer wheel" with "type hole wheel" and marked it in red

QUESTION18: the green magnification is not labelled.

RE: Thank you very much for your valuable comments. Through reading and consulting the literature found the enlargement in the picture may not need to be enlarged, I refer to this paper in Agriculture.

Such as (WANG C, LI H, HE J, et al. Optimization Design of a Pneumatic Wheat-Shooting Device Based on Numerical Simulation and Field Test in Rice– Wheat Rotation Areas [J]. Agriculture, 2022, 12(1): 56. https://doi.org/10.3390/agriculture12010056).

QUESTION19: there are numbers as labels but there is no key. Add a key

RE: Thank you very much for your valuable comments. I have replaced Figure 4 and marked it in red.

QUESTION20: the hole wheel angular speed is set by the motor independently or it is driven by the tractor forward speed? Clarification needed.

RE: Thank you very much for your valuable comments. The BeiDou navigation receiver receives the forward speed signal from the tractor and transmits it to the communication controller, which then processes and controls the motor speed to control the hole wheel angular speed. I have amended it according to your comments and marked it in red.

QUESTION21: Line 200: “lateral pressure” is not appropriate. It is not a pressure but it is the lateral force exerted on the inner wall. In addition, it is not clear for what "lateral" stands. It seems to normal to the contact surface of the hole wheel. It should be better to rearrange the force directions and nomenclature according to normal and tangential forces with respect to contact surfaces.

RE: Thank you very much for your valuable comments. The lateral pressure you refer to I have changed to a lateral force and marked it in red., in addition, the lateral you point out is the force of normal surface contact, it is a force at the point of contact, I have divided it into normal and tangential forces in the equation below.

QUESTION22: change “quality” to “quantity”.

RE: Thank you very much for your valuable comments. I have changed "quality" to "quantity" and marked it in red

Thank you very much for your valuable opinions. Please review the revised article!

Author Response File: Author Response.docx

Reviewer 2 Report

Substantive assessment:
The trip-hole technique (applying fertilizers at different depths depending on the degree of development of the plant, in this case corn) is really innovative. Not even in Europe known unlike strip-till. Therefore, it is worth disseminating it, provided that it actually gives better financial results for the agricultural entrepreneur.
The proposed method of fertilization is purely mechanical and does not correspond to the assumptions of modern Agriculture 4.0 (in the moment 5.0) - digital farming. This is because it is intelligent agriculture, based on the automation of processes taking into account satellite observations, real-time soil research (based on a soil map) in order to optimize sustainable agriculture.
In addition, today, before the prototype is created, strength simulations are carried out with the use of FEM computer techniques (CAD / CAE).
The next stage of research after the production of the prototype is reliability testing, which is important for practice. There are many methods for quantifying the reliability and durability of technical facilities. However, the specificity of the operation of agricultural machinery and vehicles requires special methods dedicated to them. Such exemplary methods are included, for example, in the works of PULS https://puls.edu.pl/en/ (as in the bibliography, item no. 33: Renata Gaj and others):

Durczak, K.; Selech, J.; Ekielski, A.; Żelaziński, T.; Waleński, M.; Witaszek, K. Using the Kaplan–Meier Estimator to Assess the Reliability of Agricultural Machinery. Agronomy 2022, 12, 1364. https://doi.org/10.3390/agronomy12061364

Therefore, it is worth studying them and using them in further field or accelerated research (at measuring stations) on a larger population.

Editorial notes:
• few keywords
• there should always be a punctuation mark at the end of a sentence (you know 273)
• uncertainty of measurements is missing, e.g. in tables 1 and 2
• I don't know if picture 3 is ok (there are links and no parts)?
• there should be a space of one space between the numerical value and the measurement unit (e.g. in lines 151 and 158, 169 and 170, 379, 466)
• the better unit for the rotational speed is rpm (instead of r/min) e.g. in lines 187 and 235)
• numbers in subscripts are written in plain script as in 242; this rule is not followed throughout the typescript (e.g. 250, 181-183).

Author Response

Dear peer reviewers and editors

Hello! Thank you very much for your professional and wise comments on this article. According to the experts' questions and opinions, the author gives a detailed explanation in the form of one question and one answer, and marks the manuscript with red font in the corresponding position, as follows:

QUESTION1: few keywords.

RE: Thank you very much for your valuable comments. The author has deleted some keywords.

QUESTION2: there should always be a punctuation mark at the end of a sentence (you know 273).

RE: Thank you very much for your valuable comments. The author has added the punctuation mark at the end of a sentence and marked it in red.

QUESTION3: uncertainty of measurements is missing, e.g. in tables 1 and 2.

RE: Thank you very much for your valuable comments. Sorry I don't know what you are referring to, it shows OK on my end.

QUESTION4: I don't know if picture 3 is ok (there are links and no parts)?

RE: Thank you very much for your valuable comments. Sorry, this may be a display issue that I have replaced the link with a new picture 3.

QUESTION5: there should be a space of one space between the numerical value and the measurement unit (e.g. in lines 151 and 158, 169 and 170, 379, 466).

RE: Thank you very much for your valuable comments. The author added the one space between the numerical value and the measurement unit and marked them in red.

QUESTION6: the better unit for the rotational speed is rpm (instead of r/min) e.g. in lines 187 and 235).

RE: Thank you very much for your valuable comments. I re-checked other articles in Agriculture and found the unit for the rotational speed is r/min.

Such as (WANG C, LI H, HE J, et al. Optimization Design of a Pneumatic Wheat-Shooting Device Based on Numerical Simulation and Field Test in Rice & dash； Wheat Rotation Areas [J]. Agriculture, 2022, 12(1): 56. https://doi.org/10.3390/agriculture12010056).

QUESTION7: numbers in subscripts are written in plain script as in 242; this rule is not followed throughout the typescript (e.g. 250, 181-183).

RE: Thank you very much for your valuable comments. The author revised the use of the subscripts and marked them in red.

Thank you very much for your valuable opinions. Please review the revised article!

Author Response File: Author Response.docx