Fertilizer Spreader Research Articles

Analysis of the main stages of improvement of technical means for the application of mineral fertilizers

In the Republic of Belarus, crop yields have increased 3.5–5 times over the past 60 years due to the combined result of work in the field of breeding, mechanization of fertilizers and chemical plant protection products application, which is a significant achievement of science and practice [1, p. 28]. One of the main criteria for evaluating the effectiveness of mineral fertilizers is considered to be the payback of 1 kg of NPK, which should be at least 8 kg of grain or 10–12 feed units by all crops on arable land [2, p. 113; 3]. To achieve such results, spreaders must perform high-quality distribution of mineral fertilizers within the established agrotechnical deadlines. The criterion for assessing the quality of the distribution of mineral fertilizers over the field area is the coefficient of variation, which is defined as the ratio of the standard deviation to the average dose. In addition to uniform distribution over the field area, high-quality incorporation of mineral fertilizers with tillage tools is also essential. As for the timeliness of applying the specified doses of fertilizers within the established agrotechnical deadlines, the most important factors here are the availability of equipment at farms during the busiest period and provision of high-performance fertilizer spreaders. It should be considered, that agricultural chemicalization machines are used from early spring to late autumn, and their annual load exceeds the same indicator for other agricultural machinery. In addition, the operation of fertilizer spreaders involves interaction with aggressive media, which imposes appropriate requirements to ensure their reliability. It should be noted that currently unmanned aerial vehicles are beginning to be actively used to introduce chemicals [4, p. 2]; publications on the development and testing of nanofertilizers are increasingly appearing in the scientific literature [5, p. 319]. In this regard, in order to determine further trends in the improvement of technical means for fertilization, it is necessary to analyze the main stages of the development of these technical means and identify the distinctive stages of their improvement.

Use of small-sized units when spreading fertilizers on mountain slopes

BACKGROUND: The results of RD on a laboratory sample of the unit for spreading mineral fertilizers on mountain slopes, which can increase labor productivity and yield rate of mountain forage lands by 15–20%, are presented. AIM: Development of a small–sized laboratory sample of the unit for surface spreading of mineral fertilizers, ensuring accelerated restoration of productive and qualitative functions of natural grass stands of fallow forage lands. METHODS: The technical expertise and testing of the unit and the technology were carried out in the mountainous zone of the Republic of North Ossetia — Alania (Dargava basin, the station of North Caucasian Research Institute of Highland and Piedmont Agriculture) at an altitude of 1540 meters above sea level. The indicators of the test conditions and functional performance of the unit have been determined according to the OST 10.5.1-2000 industry standard. Surface fertilization was carried out according to the OST 10.7.1.-2000. “Testing of agricultural machinery. Machines for applying mineral fertilizers, lime materials and gypsum” industry standard. The study subject was the technology of spreading granular fertilizers, the design of the unit and working bodies: pendulum spreading devices, spreading rates and method of spreading fertilizers. RESULTS: A laboratory sample of the small-sized unit based on the KChG-2.4 cultivator of North Caucasian Research Institute of Highland and Piedmont Agriculture design for surface application of mineral fertilizers has been developed and manufactured. The block module is a hinged frame structure with a tow-lifting device, pendulum spreading tubes and rolling rollers installed on it. The considered motion of the mining unit is across the slope from top to bottom in a shuttle manner with rolling of the sown granules by rolling rollers. The tests were carried out on a rarefied section of the northern slope with a steepness of 13–16° in the area “Sugsadtanrag”. CONCLUSION: The practical application of the small-sized unit for surface spreading of mineral fertilizers with their subsequent rolling in areas in mountainous and foothill zones will ensure a reduction in the degradation processes of slope areas by accelerating the restoration of the quality and quantity of perennial grasses of fallow forage lands.

Performance Assessment of the Small and Medium-Scale Coconut Weeder Cum Fertilizer Applicator Developed by Rajarata University of Sri Lanka

The enhancement of coconut yield significantly hinges on proper weeding and chemical fertilizer application. In Sri Lanka, several mechanical methods have been introduced for weeding and fertilizer application of coconut, but the traditional manual approach persists most popular, despite being time, labor cost intensive. Moreover, the introduced technologies were suited for large-scale coconut cultivation and could not cope with medium or small-scale. Furthermore, most of them are designed for a single application; weeding or fertilizing. Thus, the Faculty of Agriculture, Rajarata University of Sri Lanka (RUSL), developed a coconut weeder cum fertilizer applicator for medium and small-scale coconut cultivations. However, it has not been properly evaluated and recommended for farmers. Consequently, this study sought to evaluate the performance of the above machine by conducting a comparative performance evaluation with the conventional method. A healthy, well-maintained, proper-spacing coconut plantation was selected from the faculty research unit, and each weeding and fertilizer application method was replicated ten times. In terms of performance parameters: effective field capacity, field efficiency, and weeding efficiency in mechanical and manual methods were 0.172 ha h-1, 61.86%, 66.62%, and 0.048 ha h-1, 55.34%, 60.35%, respectively. Statistical analysis indicates the mechanical method had higher field capacity and efficiency than the manual method, while weeding efficiency was not significantly different (p≤0.05). In addition, the machine had a fertilizer spreading uniformity of around 99.98% when operating at an optimum speed of 1.45 km h-1. Fertilizer application rate and performance index as a weeder were 1.7 kg/min and 1145.86, respectively. Furthermore, the fuel consumption rate of the machine was 0.733 L h-1 and its break-even point was recorded as 2.85 ha yr-1. Consequently, the coconut weeder cum fertilizer applicator proves suitable for medium and small-scale coconut cultivations in Sri Lanka.

Design and Parameter Optimization of a Combined Rotor and Lining Plate Crushing Organic Fertilizer Spreader

To address the inefficient crushing of fertilizer during the mechanized spreading process caused by the caking of high-humidity organic fertilizer, a fertilizer spreader with a combined rotor and lining plate crushing mechanism was proposed in this paper. With the introduction of the basic structure and working principle of the spreader, a particle group model for an organic fertilizer consisting of both caked and bulk fertilizer was built, based on the Hertz–Mindlin model with bonding and the Hertz–Mindlin model with JKR contact, in EDEM to construct an organic fertilizer-crushing-and-spreading model. With the rotor speed, the axial distance of the hammer, and the number of circumferential hammer groups as the experimental factors and the maximum broken bond rate of the caked organic fertilizer and the minimum coefficient of variation of spreading uniformity as the experimental indices, the Box–Behnken test method was employed to establish regression equations for response surface analysis and multi-objective optimization of the test results. The results indicated that, when the rotor speed was 6.47 Hz, the axial distance of the hammer was 90.30 mm, the number of circumferential hammer groups was five, the broken bond rate reached 90.86%, and the coefficient of variation was 21.45%. Verification tests under these conditions showed a broken bond rate of 90.03% and a coefficient of variation of 22.12%, which were consistent with the optimization results. Therefore, our research provides a reference for the structural design of an organic fertilizer spreader and the optimization of its working parameters.

EVALUASI TEKNIS KONSEP PADA DESAIN ALAT PENEBAR PUPUK BUTIRAN

The technique of spreading fertilizer on rice plants is an important part of equalizing land fertility. In general, farmers use their hands to spread granular fertilizer. The spreading process results in an irregular distribution of fertilizer and also takes a relatively long time. The aim of this research is to design a granular fertilizer spreader based on a technical evaluation of the concept. The Pahl and Beitz design method became a theoretical reference in finalizing the design of the granular fertilizer spreader form. Working drawings are prepared based on ISO standards using Solidwork 2018 software. Based on the results of the technical evaluation of the concept, the design of the granular fertilizer spreader is composed of thirty-three constituent components.

The Effect of Foliar Application of Azolla Liquid Organic Fertilizer on Growth and Yield of Rice in Swampy Soil

Rice cultivation faces challenges due to limited land availability despite increasing demand. Utilizing swamp land for cultivation presents an alternative, albeit hindered by difficult-to-control water conditions and less effective fertilizer spread. To ensure optimal nutrient supply, foliar application of Azolla liquid organic fertilizer (LOF) is explored. This study investigates the ideal concentration and frequency of Azolla LOF application for rice growth and yield. Employing a split plot design, the main plot assesses LOF concentration (3%, 6%, 9%, 12%), while the subplot evaluates application frequency (1, 2, 3 times). Results indicate that a 9% LOF concentration yields the highest tiller count (17.99), longest panicle (25.788 cm), highest grain count per panicle (158.2978), heaviest grain weight per hill (45.878 g), and highest grain weight per plot (3457.52 g). However, the fastest flowering period (54 DAP) occurs with a 12% LOF concentration. Applying Azolla LOF three times achieves the earliest flowering (55.25 DAP), while two applications yield the longest panicle (25.03 cm). Notably, no interaction is observed between LOF concentration and application frequency on rice growth and yield. These findings provide insights into optimizing Azolla LOF application for enhanced rice cultivation in swamp lands.

Design of a Fertilizing Robot Application with Regard to Energy Consumption

Electrically driven agricultural robots experience faster battery depletion than vehicles moving on asphalt because higher rolling and traction resistance require more energy. The problem arises in areas without access to the electrical grid, where charging electrically driven agricultural robots is not possible, resulting in interruptions to the robot's continuous operation. A combined energy production station powered by biogas, hydrogen, and solar energy with the prototype of autonomous fertilizing robot for blueberry plantations, to perform plant-based precision fertilization on depleted milled peat fields was created by the agrorobotics working group of the Estonian University of Life Sciences [1, 2]. The station includes unique components such as an automatic battery exchange system and an electric generator with a membrane motor. These, together with a solar energy and electric generator control system, as well as a battery charger, are mounted on a mobile platform (Figure 1). The objective of this article was to determine the energy requirements of an autonomous fertilizing robot during movement in the field and for carrying out technological operations. For this purpose, the mechanical power and energy required for the operation of the robot fertilizer spreader were first determined. Based on this, an accumulator with suitable power and capacity for the operation of the robot fertilizer spreader was selected. The travel distance of the robot on a single charge of the chosen accumulator was determined, as well as the traction power efficiency and specific power.

Challenges in the Planning, Construction and Farming Practices in Agrivoltaic Systems With Vertically Mounted Panels

Several challenges in planning, construction, and farming practices hinder the optimization of agrivoltaic systems (AS) and the achievement of optimal crop production. This paper identifies and addresses these issues while presenting initial solutions. One specific type of AS involves vertically mounted panels on arable or grassland sites. The installation of panel rows divides large fields into narrow units, restricting the use of farming implements with different working widths. Implement widths must align with the spacing between panel rows, which often results in residual strips or overlapping issues when field operations are carried out. Furthermore, boundary effects in AS are more pronounced, impacting yield along field borders. The presence of panel rows also complicates driving operations, requiring reduced speeds and posing collision risks between implements and panels. Soil compaction during AS construction, microclimate variations, and panel contamination by dust, or spray drift deposits further affect plant growth and solar system performance. Initial solutions are proposed to address these challenges. These include careful planning of row spacing based on the working widths of critical implements such as combines, adoption of field sprayers with foldable booms, consideration of pneumatic fertilizer spreaders, and integration of precision farming techniques to manage variability within AS. Additionally, the use of construction machinery with low soil pressure, employment of steering technologies based on global navigation satellite systems, and research on panel cleaning devices are suggested. Overall, this paper highlights the need for further research and development to overcome farming challenges in agrivoltaic systems with vertically mounted panels.

Pengembangan Alat Pemupuk Jagung Inovatif untuk Ketahanan Pangan yang Lebih Baik

The development of an innovative corn fertilizer tool as an improvement on an existing concept that has been widely socialized in the farming community aims to design a fertilizer spreader tool that suits farmers' needs, with a simple technological concept, a working principle that is easy to operate and a product form that is easy to carry, and can be commercialized and is a development of previous concepts as the aim of the research carried out. Using the French method because it is considered easier to meet data needs. The design results obtained are an improvement on the research concept of previous researchers which improved the capacity where the old fertilizer tool was only able to accommodate approximately 2 Kg of fertilizer, with the new design it can accommodate 15 Kg of fertilizer, the tip of the lever is designed to be pointed so that the fertilizer enters the surface more easily. soil, while tool rods made from stainless steel can provide strength to the tool, they do not rust easily if they come into contact with water or fertilizer (chemicals) so they last a long time. Keywords: Corn Fertilizer Equipment, Capacity, Design, Innovative

Results of development of a software application for calculating the performance indicators of machines for fertilizers application

Results of development of a software application for calculating the performance indicators of machines for fertilizers application

Application of a centrifugal disc fertilizer spreading system for UAVs in rice fields

Unmanned aerial vehicle (UAV) granular fertilizer spreading technology has been gradually applied in agricultural production. However, in the process of spreading operation, the actual influence effect of each factor in field operation is still unclear. Based on the self-developed UAV fertilizer spreading system, this paper explores the effects of three factors, the baffle retraction (B), spreading disc speed (D), and UAV flight altitude (H), on the granular fertilizer spreading effect in the actual field scenarios through the orthogonal test and taking the coefficient of variation (Cv) and relative error of fertilizer application rate (λ) as the evaluation indexes. The results showed that the optimal factor level combination of Cv was 11.23 % for BbDbHa (the baffle retraction is 6 %, spreading disc speed is 600r/min, and UAV flight height is 1.5 m) at UAV flight speed of 2 m/s. The best factor level combination for λ was BbDbHb of 7.99 % (the baffle retraction is 6 %, spreading disc speed is 600r/min, and UAV flight height is 2 m). In addition, by analysing the influence of the weather and the vortex of the rice canopy on the actual spreading effect, it was found that the weather has less influence on the spreading effect of this system, while the vortex caused by the airflow of the UAV rotor has a certain influence on the spreading effect, which is also relatively easy to ignore in fertilizer spreading operations. The results of the study can be used to explore the operational effects of actual fertilizer application by UAVs in rice field, which will help promote the development of UAV spreading technology and provide a reference for precision fertilizer application through agricultural aviation.

Investigating Fertilizer Spreader Blades for Improved Flow Behaviours and Material Resilience in Palm Plantation Settings

Fertilizer spreaders play a crucial role in evenly distributing granule fertilizer across palm plantations. However, in specific areas where growth conditions are unsuitable, fertilizer application becomes unnecessary. Therefore, this study aims to improve granule fertilizer distribution efficiency through enhanced fertilizer blade design. Using Finite Element (FE) simulation, the stress deformation and deflection of the existing spreader blade were evaluated. Meanwhile, Computational Fluid Dynamics (CFD) simulation was used to investigate the influence of spreader design on fertilizer projection speed and direction in the case of open and closed side discharge. The study revealed that the applied forces increased both the critical stress deformation and deflection. To ensure the fertilizer spreads properly over the desired area, the initial velocity had to be increased proportionally with an increase in the angle of direction. These findings contributed to a deeper understanding of the relationship between fertilizer projection velocity, spreader blade strength, and flow behaviour, enabling the reduction of waste in granule fertilizer, while enhancing the operational efficiency and reliability of fertilizer spreader.

Case Study on the Economic and Environmental Impact of the Introduction of the Variable-Rate Distribution of Fertilizer in Wheat (Triticum aestivum L.) Cultivation

Fertilization plays a strategic role in the cultivation of wheat, contributing to harvest yield, both in quantitative and qualitative terms. However, similarly to all farm inputs, it has both economic and environmental impacts due to fertilizer dispersion into the environment during its distribution, as well as any excess fertilizer not used by the crop. Precision agriculture, which introduces the possibility of distributing fertilizer following prescription maps, has an immediate effect on dosage compliance according to the request and potential for use by each homogeneous area of the crop. An experimental field (about 15 hectares) at the Council for Agricultural Research and Economics (CREA) of Treviglio (BG) in Northern Italy was fertilized using a centrifugal fertilizer spreader combined with a tractor, equipped with a satellite system to distribute urea led by prescription maps. The purposes of this research were to verify (i) the effect of fertilization, performed with precision agriculture (PA) criteria at a variable rate; (ii) the comparison of the economic impact of the quantities of fertilizer required by precision agriculture compared to the distribution required in previous years (fertilizers administered according to conventional agriculture). The treated areas showed a significant yield improvement (almost 14%) when fertilization was performed according to the prescription map. With a negligible margin of error of less than 0.001, the total amount of fertilizer used was the same in both years.

Structure and operation mode of centrifugal side-throwing organic fertilizer spreader for greenhouses

A centrifugal side-throwing organic fertilizer spreader is designed to improve the versatility of organic fertilizer spreaders. A discrete-element method is used to investigate the driving layer limit height of the conveyor and the diversion of the guide vane, observe the jet and the disk distribution of organic fertilizer at different fertilizer drop positions, and determine that the gap between the fan blade and guard plate significantly affects the distribution of the organic fertilizer. A mathematical model of openings and flow rate is established using bench tests. Static tests reveal that the coefficient of variation (CV) can be optimized to 15–35%. The operation mode is investigated in dynamic tests by selecting two groups of representative static test results. Group 2 had a coefficient of variation of 15.73% at 0 mm overlap. Group 3 had a coefficient of variation of 18.52% at 1200 mm overlap. The study provides a feasible solution for the design of organic fertilizer spreaders for greenhouses.

Optimization of and experimentation with a bifurcated swing tube strip fertilizer spreading device based on MBD-DEM coupling.

To improve the utilization rate of fertilizers, realize the precise spreading of fertilizers in controllable strips, and ensure the uniformity of fertilizer spreading in both longitudinal and transversal directions, a bifurcated swing tube fertilizer spreading device driven by a spatial hammer pendulum crank mechanism was designed. First, the drive mechanism was designed based on the cylindrical pair of the mechanism. A mathematical model pendulum equation was used to design the swing tube, and the equation of motion of fertilizer particles was established by analyzing the motion and force of fertilizer particles in fertilizer spreading. The dynamic parameters of the fertilizer spreading device (nozzle height, forward velocity, and swing frequency) were identified as the test factors affecting the uniformity of fertilizer spreading. Second, the coupling model based on MBD-DEM was established, and the coupling simulation analysis of the fertilizer spreading process was carried out using EDEM-RecurDyn software. Taking the nozzle height, forward velocity, and swing frequency as test factors and the uniformity coefficient of longitudinal and transversal fertilizer spreading as evaluation indexes of the fertilizer discharging effect, we analyzed the influence of a single factor on the indexes. Moreover, the ternary quadratic generalized rotating combination response surface test established the regression equations of three factors and two evaluation indexes. Finally, the simulation and bench test were verified under the optimal combination of parameters and compared with the single swing tube bench test with the same parameter conditions. The results of the single-factor test showed that the fertilizer discharge effect was better when the nozzle height was 350.0-450.0 mm, the forward velocity was 0.5-1.5 m/s, and the swing frequency was 1.40-2.00 Hz. The results of the response surface test proved that the nozzle height, forward velocity, and swing frequency all had a highly significant effect on the uniformity coefficient of fertilizer spreading in the longitudinal and transversal directions (P<0.01). Moreover, the optimization concluded that when the nozzle height is 450.0 mm, the forward velocity is 0.5-0.8 m/s, and when the swing frequency is within the range of 1.40-2.00 Hz, the uniformity coefficient of longitudinal fertilizer spreading is ≤25% and the uniformity coefficient of transversal fertilizer spreading is ≤45%. The results of bench validation showed that the errors of longitudinal and transversal fertilizer spreading uniformity coefficients in the bench test were 3.46% and 1.44%, respectively, and the simulation agreed with the bench test. The results of comparative tests showed that the uniformity coefficient of the longitudinal and transversal of the fertilizer spreading device was reduced by 50.33% and 14.95%, respectively, for the bifurcated swing tube compared with that of the single swing tube. It is proved that the bifurcated swing tube strip fertilizer spreading device can achieve the purpose of uniform fertilizer spreading and performs better than the single swing tube in fertilizer spreading. The results and methods of this study can provide a reference for the design of swing tube strip fertilizer spreading devices and related fertilizer spreading performance tests.

Designing a Fertilizing Robot Application Considering Energy Efficiency

Abstract Electrically driven agricultural robots encounter accelerated battery depletion compared to vehicles operating on asphalt due to heightened rolling and traction resistance necessitating increased energy consumption. This issue becomes pronounced in regions devoid of access to the electrical grid, precluding the possibility of recharging electrically driven agricultural robots and consequently leading to interruptions in their uninterrupted functionality. To address this challenge, the agrorobotics working group at the Estonian University of Life Sciences devised a novel solution: a combined energy production station leveraging biogas, hydrogen, and solar energy. This station was integrated with a prototype autonomous fertilizing robot tailored for blueberry plantations to conduct precision fertilization on depleted milled peat fields. Distinctive features of the station encompass an automated battery exchange system and an electric generator equipped with a membrane motor. These components, in conjunction with a solar energy and electric generator control system, alongside a battery charger, are affixed onto a mobile platform. The primary objective of this study was to ascertain the energy requisites of an autonomous fertilizing robot during field traversal and while executing technological operations. To achieve this aim, the mechanical power and energy necessary for the operation of the robot fertilizer spreader were initially quantified. Subsequently, an accumulator possessing suitable power and capacity for the operation of the robot fertilizer spreader was chosen. The article further delineates the determination of the travel distance achievable by the robot on a single charge of the selected accumulator, in addition to evaluating the traction power efficiency and specific power.

TECHNICAL AND ECONOMIC EVALUATION OF THE PRODUCTION OF COMPOSTS FROM LITTER MANURE IN THE CONDITIONS OF THE FARM

The purpose of the study was to increase the efficiency of compost production from organic raw materials of agroecosystems through the development and implementation of scientifically based complex technical, technological solutions and economic assessments based on the results of production tests of technical means in real farming. The results of production tests of mechanized technology for processing litter chicken manure based on sunflower seed husks into high-quality environmentally friendly organic fertilizers-composts are considered. The research was carried out in the conditions of the farm with the provision of effective preparation of the mixture by mechanical complexes of machines and intensive aeration. Mechanized technology using the modernized PRT-10 is recommended for small farms with a compost preparation volume of up to 2-3 thousand tons per year and provides highly effective fertilizers for 45–60 days. The use of the AZK-2 aerator-mixer on raw materials with a density of more than 600 kg/m3 is necessary with aggregation with an MTZ-80 tractor equipped with a crawler, providing a working speed of 0.2 m/s. The capacity of the mixing aerator is 300-500 t/h. Two variants of technological maps have been developed for completing mechanized compost production technology with technical means. The first one is based on the use of the AZK-2 trailed aerator-mixer, and the second option is the modernized PRT-10 organic fertilizer spreader paired with the T-156K loader. The largest difference in technological indicators is observed in fuel consumption – almost 2.5 times in favor of using the trailed aerator-mixer AZK-2. The economic assessment of the planned processing of raw materials at 3000 tons shows that the unit costs for the production of compost in this case are 107.58 UAH/t as opposed to 176.28 UAH/t in the first version.

Study on the Influence of Grooved-Wheel Working Parameters on Fertilizer Emission Performance and Parameter Optimization

The grooved-wheel fertilizer machine is one of the most widely used pieces of fertilization equipment. However, detailed information on the fertilizer filling status and the mechanism of particle interactions during the operation of the grooved wheel remains limited. To delve into the underlying mechanisms through which working parameters affect fertilization performance, this study, building upon prior research, conducted a qualitative analysis and numerical investigation of fertilizer particles using the Discrete Element Method. The analysis examined the impact of three working parameters, namely the grooved-wheel speed, working length, and forward speed of the fertilization equipment, on the morphology, forces, and kinetic properties of the fertilizer particles. Combining this analysis with orthogonal experimental research, we optimized the aforementioned working parameters. Both simulation and benchtop experimental results indicate that the grooved-wheel speed and working length influence the fertilizer filling status, while the forward speed of the equipment has no effect on the filling status. The connection between fertilizer force and kinetic changes is influenced by particle-free space. The lowest coefficient of variation (CV) for fertilization uniformity was observed at the grooved-wheel speed of 53.64 r/min, the wheel working length of 33.45 mm, and the forward speed of 0.7–1 m/s. The research findings contribute to a better understanding of the influencing mechanism of particle movement and fertilization outcomes in the operation of grooved-wheel fertilizer spreaders. This understanding enables precise control of the fertilizer application process, facilitating accurate and efficient fertilization. As a result, it enhances fertilizer utilization rates and reduces agricultural costs.

Impact of Airflow Rectification on Spreading Uniformity for UAV-Based Multichannel Pneumatic Granular Fertilizer Spreader

Unmanned aerial vehicles (UAVs) are an important part of smart farms and have been widely used in granular fertilizer spreading. The multichannel pneumatic granular fertilizer spreader (MPGFS) has the advantages of light weight and precision spreading, and has been applied to UAV variable rate fertilization. Based on the problem that the airflow field disorder of the existing MPGFS reduces the uniformity of spreading, the aim of this study was to further improve the performance of the MPGFS through rectification. The computational fluid dynamics and discrete element method (CFD-DEM) and coupling simulation method were used to study the characteristics of the airflow field and fertilizer particle motion, and a honeycomb rectifier and grid rectifier were developed. The aperture of the honeycomb rectifier and the grid size of the grid rectifier were optimized. Then, the test bench was built to test the consistency of the discharge rate of each channel and the spreading uniformity of the MPGFS. The simulation results of the existing MPGFS showed that the airflow provided by the axial flow fan was rotational, and this caused the particles’ motion to be skewed in the shrinkage section, so the discharge rate of each channel was inconsistent. The airflow field analysis results of the shrinkage section showed that the airflow rotation was reduced after the rectification of the honeycomb rectifier and the grid rectifier. The bench test results showed that the coefficient of variation (CV) of each channel discharge rate of the existing MPGFS was 20.16%, the optimal honeycomb rectifier was 13.07%, and the optimal grid rectifier was 5.27%. The bench test results of spreading uniformity show that the CV of spreading uniformity of the existing MPGFS was 15.32%, the optimal honeycomb rectifier was 15.81%, and the optimal grid rectifier was 8.02%. The grid rectifier spread pattern was more reasonable and the CV of uniformity was better. This study demonstrated that the use of a grid rectifier to rectify the airflow field of MPGFS can effectively improve its spreading uniformity, which was of guiding significance for the design and research of MPGFS.

离心圆盘式有机肥撒施机改进设计与仿真分析

Aiming at the poor efficiency in crushing a handful of caking organic fertilizers spraying from the traditional disc spreader, an improved disc spreader equipped with spike-tooth crushing unit was designed with the introduction of its structural composition and working principle. Also simulation experiments were carried out based on the discrete element method according to the solutions made before and after the structural improvement. Firstly, a granular organic fertilizer model was established based on the EDEM and a caking organic fertilizer bonding model was built based on the HMB (Hertz-Mindlin with bonding) contact model. Then two organic fertilizer spreading models corresponding to the solutions were respectively established, based on which simulation experiments were repeated three times on the spreading process. The analysis on the particle velocity vector diagram revealed the interaction relationship between organic fertilizers with the toothed shaft, external wall and disk, verifying the crushing mechanism of crushing unit. By calculating the total number of the bonds generated and broken in the spreading process in both of the spreading models, the average broken rate of bonds in the spreading process was separately 58.87% and 98.05% based on each solution, revealing that the improved solution outperformed the traditional solution in terms of the efficiency in crushing the caking organic fertilizers. This research will be a reference in designing the critical components or improving the overall performance of disc spreader.