Simulation and Validation of the Air Flow generated by a Multi-Channel Air-Assisted Sprayer

Chao, Xiangyun; Chen, Shang; Qiu, Wei; Lv, Xiaolan; Li, Hua; Han, Changjie; Ahmad, Fiaz

doi:10.1109/access.2019.2927377

Cited by 9 publications

(4 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The current research on wind field is still mainly based on computational fluid dynamic (CFD) simulation, [35][36][37] which usually sets the canopy as a porous medium. The obtained results have certain significance but differ from the actual values.…”

Section: 'Turbulence Effect' Inside the Canopymentioning

confidence: 99%

Wind field and droplet coverage characteristics of air‐assisted sprayer in mango‐tree canopies

Jiang

Yang

et al. 2022

Pest Management Science

View full text Add to dashboard Cite

BACKGROUND Air‐assisted sprayers is one of the primary fruit tree pest control approaches in agricultural production. It is necessary to study the influence of multiple factors on both wind field and droplet coverage of air‐assisted sprayers. In this article, foliage area volume density (FAVD) and power gradient were considered factors, and field tests were conducted in an orchard to determine such influence. RESULTS The results showed that in‐canopy wind speed was mainly affected by the air‐assisted sprayer. FAVD showed significance to the wind speed and droplet coverage inside canopies (P < 0.001), compared with power gradient (P > 0.05). With the increase of FAVD, the wind speed in the bottom layer of canopies first increased and then decreased, while the wind speed in the middle and top layers first decreased and then increased. Meanwhile, the wind field was mainly concentrated on the surface of canopies and gradually approached the canopy center as the power gradient increased. Furthermore, a Back‐Propagation (BP) neural network prediction model was constructed to predict droplet coverage at any canopy location to avoid repeated experiments. The overall correlation coefficient (R) of this model was about 0.731, indicating good fitting performance. CONCLUSION FAVD has a significant effect on wind speed and droplet deposition inside the canopy, and the air‐assisted sprayer parameter setting should consider the effect of FAVD. The prediction model can predict droplet deposition inside the canopy without repeating. The study can provide a reference for selecting operating parameters of air‐assisted sprayers and help reduce droplet loss and environmental pollution. © 2022 Society of Chemical Industry.

show abstract

Section: 'Turbulence Effect' Inside the Canopymentioning

confidence: 99%

Wind field and droplet coverage characteristics of air‐assisted sprayer in mango‐tree canopies

Jiang

Yang

et al. 2022

Pest Management Science

View full text Add to dashboard Cite

show abstract

“…Their results demonstrated that multi-duct pesticide application machines in orchards are superior to other sprayers in terms of droplet distribution uniformity, coverage and drift degree during the copying spray [16]. Chao, 2019, conducted a computational fluid dynamics (CFD) simulation of a multi-channel air-assisted sprayer and investigated the effects of the rotation speed of the draught fan (600-1800 rpm) and distance to the air inlet (0-6.0 m) on the airflow field distribution. An experimental verification revealed that the measured results were consistent with the simulation results in the test range [17].…”

Section: Introductionmentioning

confidence: 99%

“…Chao, 2019, conducted a computational fluid dynamics (CFD) simulation of a multi-channel air-assisted sprayer and investigated the effects of the rotation speed of the draught fan (600-1800 rpm) and distance to the air inlet (0-6.0 m) on the airflow field distribution. An experimental verification revealed that the measured results were consistent with the simulation results in the test range [17]. Ashenafi T. Duga et al, 2015, evaluated outlet airflow distribution in orchards by establishing the air delivery system and the CFD model of fruit trees with different shapes, and verified its accuracy [18].…”

Section: Introductionmentioning

confidence: 99%

Performance Analysis and Testing of a Multi-Duct Orchard Sprayer

Wang

et al. 2023

Agronomy

View full text Add to dashboard Cite

A multi-duct orchard sprayer is designed in this paper to address the problem of low droplet coverage during plant protection in walnut orchards in South Xinjiang, China. This spray comprises a base frame, a pesticide tank, an air delivery system, a copying base frame and a drive system. Effects of the sprayer structure on the flow field were simulated using computational fluid dynamics. Operation parameters were optimised using the response surface analysis and validated using a field test. The results demonstrated that five jet tubes in the simulation design could fulfil the design requirements of GB/T 32250.3-2022. The upper, middle and lower droplet coverages were 74.92%, 90.01% and 69.9%, respectively, when the sprayer’s advancing speed, the angle of jet tubes and the nozzle diameter were 0.53 m/s, 70.27° and 0.81 mm, respectively. The machine can effectively enhance the spraying efficiency and droplet coverage of each canopy during plant protection operations in the new walnut orchards of South Xinjiang, China, and provide references for designing and optimising fruit tree spraying machinery.

show abstract

“…Air-assisted spraying technology delivers atomized liquid to a canopy with the help of high-speed airflow, which helps to achieve a more homogeneous distribution and significantly improves the deposition of droplets and is, therefore, one of the most important technical measures for increasing the efficiency and reducing the application of pesticides in orchards ( Planas et al., 2002 ; Panneton et al., 2005 ). Presently, researchers have conducted several studies on air-assisted application technology, mostly focusing on changing the type of fan or related parameters to investigate the movement of airflow in the air ( Mion et al., 2011 ; Chao et al., 2019 ; Qiu et al., 2020 ). However, the presence of canopy branches and leaves in fruit trees inevitably makes airflow movement in the canopy different from that in the air.…”

Section: Introductionmentioning

confidence: 99%

Model construction and validation of airflow velocity attenuation through pear tree canopies

et al. 2022

Self Cite

View full text Add to dashboard Cite

To investigate the airflow velocity attenuation inside pear tree canopies and the factors that influence its effect on air-assisted spraying, the relationship between the resistance of the canopies to airflow and airflow velocity inside the canopies was determined. At the same time, the theoretical model of airflow velocity attenuation in the canopy was constructed, in which the velocity attenuation factor k and the incoming velocity were the model input values, and the airflow velocity in the canopy was the model output value. Then, experimental verification of the theoretical model was completed. The determination test of airflow velocity inside canopies with three leaf area densities revealed that the error range between the established theoretical model and the experimental airflow velocity inside the pear tree canopy was 0.11–1.25 m/s, and the mean size of the model accuracy was 83.4% under various working conditions. The results revealed that the region from a depth of 0 m to 0.3 m inside the canopy was the rapid attenuation area of the airflow and that from 0.3 m to 0.9 m was the low attenuation area. Furthermore, they revealed that high-speed airflow could strongly disturb the outer branches and leaves, greatly changing the windward area of the canopy blades and thus affecting the accuracy of the model. By introducing a dynamic parameter of the canopy leaf windward area for model correction, the R2 of the model was above 0.9. Finally, validation of the model was performed in an air-assisted spraying operation in an orchard. This study can provide a theoretical basis for the regulation of airflow parameters of air-assisted spraying of pear trees.

show abstract

Simulation and Validation of the Air Flow generated by a Multi-Channel Air-Assisted Sprayer

Cited by 9 publications

References 20 publications

Wind field and droplet coverage characteristics of air‐assisted sprayer in mango‐tree canopies

Wind field and droplet coverage characteristics of air‐assisted sprayer in mango‐tree canopies

Performance Analysis and Testing of a Multi-Duct Orchard Sprayer

Model construction and validation of airflow velocity attenuation through pear tree canopies

Contact Info

Product

Resources

About