scholarly journals Lodged Sugarcane/Crop Dividers Interaction: Analysis of Robotic Sugarcane Harvester in Agriculture via a Rigid-Flexible Coupled Simulation Method

Actuators ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 23
Author(s):  
Qingqing Wang ◽  
Qianwei Zhang ◽  
Yin Zhang ◽  
Guoan Zhou ◽  
Zhiqiang Li ◽  
...  

As a critical component of the sugarcane harvester, the primary function of the crop dividers is to lift the lodged sugarcane (LS) and reduce the loss rate of the sugarcane harvest. In this study, a rigid-flexible coupling simulation method is proposed to improve the lifting efficiency of the crop dividers on severely LS and analyze the nature of interaction between the sugarcane stalk and the crop dividers. The model’s accuracy was verified using field experiments, and the operational performance of the crop dividers on sugarcane in different lodging postures was investigated. The results showed that the curve of the vertical height of the center (VHC) fluctuated more and slipped with highest frequency during the lifting process of side and forward LS. The speed of VHC was fastest during the lifting operation of side LS. The effect of side angle on the lifting effect of sugarcane was significant; the qualified values of the VHC of sugarcane being lifted in different lodged postures were: side and reverse lodged > side lodged > side and forward lodged. The coupling method and experimental results described in this paper can provide guidance for the optimal design and field operation of the crop dividers.

Machines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 296
Author(s):  
Qingqing Wang ◽  
Ziwen Bai ◽  
Zhiqiang Li ◽  
Dongbo Xie ◽  
Liqing Chen ◽  
...  

In this paper, a new coupling simulation method is proposed for baler picker using automatic dynamic analysis of mechanical systems (ADAMS) and discrete element method (DEM). Field tests are carried out to verify the accuracy of the simulation model. By using the coupling method, not only was it obtained that the forward velocity (FV) and the ground clearance of spring teeth (GCST) are positively correlated with the pick-up loss rate (PLR), but also that the blockage of the picker mainly occurs in the straw pushing area, and an optimization plan is proposed. Through the analysis of the acting force (AF) between the roller and the track groove, we speculate that the structure of the track groove in a certain area is defective. The coupling method and optimization scheme proposed in this paper can provide a reference for the optimal design of the picker.


2019 ◽  
Vol 188 ◽  
pp. 106268 ◽  
Author(s):  
Jørgen Bremnes Nielsen ◽  
Endre Sandvik ◽  
Eilif Pedersen ◽  
Bjørn Egil Asbjørnslett ◽  
Kjetil Fagerholt

2019 ◽  
Vol 123 (1266) ◽  
pp. 1275-1296
Author(s):  
A. A. Sheikh Al-Shabab ◽  
P. G. Tucker

ABSTRACTRANS models remain an attractive turbulence simulation method which could provide some open jet aerofoil interaction analysis at a fraction of the cost of a high-fidelity LES approach. The present work explores the potential and limitations of RANS in this context by simulating an open jet aerofoil noise experiment using the aerospace oriented Menter SST RANS model. This model’s tendency to transition at a critical Reynolds number lower than the experimental value was found to impact the boundary layer development. However, the introduction of a low-Re correction improved the prediction of surface pressure and skin friction, enabling the suction surface separation bubble to be captured. The free shear layer’s virtual origin characteristics exhibited sensitivity to the interaction with the aerofoil, which can be developed into a metric of the interaction. The main challenge for RANS was accounting for the rise in background disturbance level in the working section, which is caused by the high-turbulence intensity in the free shear layers.


2021 ◽  
Vol 37 (2) ◽  
pp. 233-242
Author(s):  
Fenglei Wang ◽  
Shaochun Ma ◽  
Wenli Ke ◽  
Haonan Xing ◽  
Jing Bai ◽  
...  

HighlightsAn under-the-ground basecutting mode was employed, which is different from the typical above-the-ground basecutting mode.A series of field experiments were carried out using the response surface methodology (RSM).The complicated effect of critical parameters on three indicators (stubble breaking index, stubble uprooting index, and power consumption) was explored.The optimal values of critical parameters were determined using a multi-objective optimization method.Abstract. Basecutting is an important process in mechanical sugarcane harvesting, thus, it’s necessary to develop a high-efficient basecutter. The previous research about basecutting has mainly focused on the above-the-ground basecutting instead of under-the-ground basecutting. Therefore, the objective of this study was to analyze how the critical structural parameters, such as blade number (BN), oblique angle and bevel angle of blades (OA, BA), affect the cutting performance of a sugarcane harvester with an under-the-ground basecutting mode. A series of field tests were carried out using Liugong sugarcane harvester. The experimental indexes were determined as stubble breaking index (BI), stubble uprooting index (UI), and power consumption (PC). The ANOVA results indicated that three regression models of indicators were significant, and were in agreement with the test data. Additionally, it was concluded that OA and BN were the two most important factors when optimizing BI, UI, and PC. BA was the last factor to be considered although it had significant effect on BI and UI. The multi-objective optimization results showed that the optimal parameter combination was 3 of BN, 10° of OA, and 20° of BA, and the corresponding BI, UI, and PC reached the minimum. For sugarcane growers, reduced stubble damage and power consumption could increase the sugarcane germination and decrease the harvesting cost, respectively. For sugarcane mills, this cutting mode might cause potential decrease in sugar quality, specifically sediment levels. However, this disadvantage could be overcome by optimizing basecutter parameters. Keywords: Basecutter, Cutting mode, Power consumption, Stubble breaking, Stubble uprooting, Under-the-ground basecutting.


2020 ◽  
Vol 10 (5) ◽  
pp. 1646 ◽  
Author(s):  
Jun Fu ◽  
Haikuo Yuan ◽  
Depeng Zhang ◽  
Zhi Chen ◽  
Luquan Ren

Corn was frozen at harvest time in high-latitude areas, when corn kernel is wetter and more easily broken. When frozen corn was threshed and separated by the longitudinal axial threshing cylinder of a combine harvester, it caused a significantly high kernel damage rate and loss rate. The process parameters of threshing cylinder were optimized using RSM (response surface method) and NSGA-II (Non-Dominated Sorted Genetic Algorithm-II). The drum speed (Ds), feed rate (Fr) and concave clearance (Cc) were determined as the optimized process parameters. The loss rate (Lr) and damage rate (Dr) were indicators of operational performance. The RSM was used to establish a mathematical model between process parameters and indicators. With an elite strategy, NSGA-II was used for multi-objective optimization to obtain the optimal operational performance of the threshing cylinder. Overall, when the drum speed was selected as 384.1 rpm, the feed rate as 8.6 kg/s and the concave clearance as 40.5 mm, according to the requirement of corn harvest, the best operational performance of the longitudinal axial threshing cylinder on frozen corn was obtained. The Lr was 1.98% and the Dr was 3.49%. This result indicated that the applicability of the optimal process parameters and the optimization method of combining NSGA-II and RSM was effective for determining the optimal process parameters. This will provide an optimization method for synchronously reducing the loss rate and damage rate of grain harvesters.


1997 ◽  
Vol 11 (4) ◽  
pp. 677-682 ◽  
Author(s):  
Edward P. Richard

Field experiments were conducted in Louisiana to evaluate the effectiveness of tillage, tillage plus herbicide, and herbicide-only fallow programs in controlling bermudagrass. Tillage of fallow fields three times at 3- to 4-wk intervals between row formation in late May and planting in late September or early October reduced bermudagrass infestations in the newly planted crop in December 44 to 51%. When the final tillage operation was replaced by glyphosate postemergence at either 2.24 or 3.36 kg ai/ha in late August, bermudagrass infestation level in December on the surface of the newly planted rows was reduced to below 20%. Two applications of glyphosate at 3.36 kg/ha were more effective than tillage only and as effective as tillage twice followed by glyphosate in reducing bermudagrass infestation levels in the newly planted crop. Application of atrazine at 3.36 kg ai/ha, imazapyr at 0.68 kg ai/ha, metribuzin at 1.68 kg ai/ha, or sulfometuron at 0.14 and 0.28 kg ai/ha to newly formed rows in late May of the fallow period did not reduce the need for tillage or an application of glyphosate during the fallow period to control bermudagrass, but imazapyr at 1.12 kg/ha did. Sugarcane shoot populations in December of the fallow year were similar for the treatment programs despite differences in bermudagrass infestation levels, which ranged from 11 to 94%. However, sugarcane stalk number and height and cane and sugar yield in the plant-cane crop the following year were highest when glyphosate was applied to bermudagrass as two applications either alone or following the application of atrazine or metribuzin, when tillage was followed with one application of glyphosate, and in 1 yr when imazapyr alone was applied to newly formed rows.


2015 ◽  
Vol 15 (16) ◽  
pp. 9381-9398 ◽  
Author(s):  
Y. Tang ◽  
J. An ◽  
F. Wang ◽  
Y. Li ◽  
Y. Qu ◽  
...  

Abstract. Many field experiments have found high nitrous acid (HONO) mixing ratios in both urban and rural areas during daytime, but these high daytime HONO mixing ratios cannot be explained well by gas-phase production, HONO emissions, and nighttime hydrolysis conversion of nitrogen dioxide (NO2) on aerosols, suggesting that an unknown daytime HONO source (Punknown) could exist. The formula Punknown ≈ 19.60[NO2] · J(NO2) was obtained using observed data from 13 field experiments across the globe. The three additional HONO sources (i.e., the Punknown, nighttime hydrolysis conversion of NO2 on aerosols, and HONO emissions) were coupled into the WRF-Chem model (Weather Research and Forecasting model coupled with Chemistry) to assess the Punknown impacts on the concentrations and budgets of HONO and peroxy (hydroxyl, hydroperoxyl, and organic peroxy) radicals (ROx) (= OH + HO2 + RO2) in the coastal regions of China. Results indicated that the additional HONO sources produced a significant improvement in HONO and OH simulations, particularly in the daytime. High daytime average Punknown values were found in the coastal regions of China, with a maximum of 2.5 ppb h−1 in the Beijing–Tianjin–Hebei region. The Punknown produced a 60–250 % increase of OH, HO2, and RO2 near the ground in the major cities of the coastal regions of China, and a 5–48 % increase of OH, HO2, and RO2 in the daytime meridional-mean mixing ratios within 1000 m above the ground. When the three additional HONO sources were included, the photolysis of HONO was the second most important source in the OH production rate in Beijing, Shanghai, and Guangzhou before 10:00 LST with a maximum of 3.72 ppb h−1 and a corresponding Punknown contribution of 3.06 ppb h−1 in Beijing, whereas the reaction of HO2 + NO (nitric oxide) was dominant after 10:00 LST with a maximum of 9.38 ppb h−1 and a corresponding Punknown contribution of 7.23 ppb h−1 in Beijing. The whole ROx cycle was accelerated by the three additional HONO sources, especially the Punknown. The daytime average OH production rate was enhanced by 0.67 due to the three additional HONO sources; [0.64], due to the Punknown, to 4.32 [3.86] ppb h−1, via the reaction of HO2 + NO, and by 0.49 [0.47] to 1.86 [1.86] ppb h−1, via the photolysis of HONO. The OH daytime average loss rate was enhanced by 0.58 [0.55] to 2.03 [1.92] ppb h−1, via the reaction of OH + NO2, and by 0.31 [0.28] to 1.78 [1.64] ppb h−1, via the reaction of OH + CO (carbon monoxide) in Beijing, Shanghai, and Guangzhou. Similarly, the three additional HONO sources produced an increase of 0.31 [0.28] (with a corresponding Punknown contribution) to 1.78 [1.64] ppb h−1, via the reaction of OH + CO, and 0.10 [0.09] to 0.63 [0.59] ppb h−1, via the reaction of CH3O2 (methylperoxy radical) + NO in the daytime average HO2 production rate, and 0.67 [0.61] to 4.32 [4.27] ppb h−1, via the reaction of HO2 + NO in the daytime average HO2 loss rate in Beijing, Shanghai, and Guangzhou. The above results suggest that the Punknown considerably enhanced the ROx concentrations and accelerated ROx cycles in the coastal regions of China, and could produce significant increases in concentrations of inorganic aerosols and secondary organic aerosols and further aggravate haze events in these regions.


1992 ◽  
Vol 119 (3) ◽  
pp. 383-389 ◽  
Author(s):  
R. J. Stevens ◽  
R. J. Laughlin ◽  
J. P. Frost

SUMMARYTreatments which lowered the rate of ammonia volatilization from surface-applied cattle slurry were evaluated in three field experiments during 1989/90 at the Agricultural Research Institute of Northern Ireland. The relative effects of separation, dilution with water before application and washing with a water spray after application, on ammonia volatilization rates were compared over 4 days using ventilated enclosures. As the loss rate of ammonia during the first 4 days after application was highly correlated with the loss rate over the first 4 hours after application, the loss rate in the first 4 hours was used as a rapid method to assess the efficacy of various combinations of separation, dilution and acidification. Ammonia volatilization loss rates from treatment combinations were compared to the loss rate from whole slurry.A 50% decrease in ammonia volatilization was achieved by separation through a 0·4 mm mesh, separation through a 10·0 mm mesh plus dilution with 86% by volume of water, or separation through a 2·0 mm mesh plus washing with 53% by volume of water.A 75% decrease in ammonia volatilization was achieved by acidification to pH 6·5, or combinations of separation and dilution, namely separation through a 0·4 mm mesh plus 50% dilution or separation through a 5·0 mm mesh plus 100% dilution.A 90% decrease in ammonia volatilization was achieved by acidification to pH 6·0, dilution by 50% plus acidification to pH 6·5, or separation through a 0·4 mm mesh plus acidification to pH 6·5.The effects of separation and acidification on ammonia volatilization were cumulative. There was a highly significant inverse linear relationship between ammonia volatilization rate and volume of nitric acid used. Adding 10 M nitric acid at 1·4% by volume lowered volatilization by 75% of that from whole slurry and increased the nitrogen content of the slurry by 2 g N/l, making it a more balanced NPK fertilizer for cut swards. Because the variable value of cattle slurry is due to loss of nitrogen as ammonia and smothering of the sward with slurry solids, a combination of separation or dilution to lower sward contamination and acidification with nitric acid to lower volatilization may be the best practical option for improving cattle slurry as a fertilizer for cut grass.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Shaoqing Tian ◽  
Rongrong He ◽  
Chongli Huang ◽  
Qiong Feng ◽  
Fan Jiang

In order to explore the influencing factors of the e-government responsiveness in China, the System-Competition-Interaction analysis model was proposed to reflect the ability of e-government to respond to citizens’ demands. 960 pieces of information were collected from 480 local e-government websites in China, and field experiments were conducted on how local governments responded to citizens’ demands. The results show that there are regional differences in e-government responsiveness in China. The response probability of Northeast China is the lowest, and that of western region is the slowest. The response system and neighborhood effect are the core elements that affect e-government responsiveness. The interaction demands of citizens can not significantly affect government responsiveness. According to the research results, the practical enlightenment is that the future should change from “system-driven response” and “competition-driven response” to “citizen-driven response,” which is of a certain practical significance for improving the response level of e-government of local governments in China.


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