Decoupling on Influence of Air Droplets Stress and Canopy Porosity Change on Deposition Performance in Air-assisted Spray

被引:0
|
作者
Liu X. [1 ,2 ]
Song L. [1 ]
Cui H. [1 ]
Liu Y. [1 ]
Liu X. [1 ,2 ]
Wu M. [1 ]
机构
[1] School of Mechanical and Electronic Engineering, Shandong Agricultural University, Tai'an
[2] Shandong Agricultural Equipment Intelligent Engineering Laboratory, Tai'an
[3] Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment, Tai'an
关键词
Air-assisted spraying; Airflow droplets stress; Canopy porosity change; Decoupling; Droplets deposition;
D O I
10.6041/j.issn.1000-1298.2021.08.011
中图分类号
学科分类号
摘要
In the air-assisted spray, the change in the porosity of the canopy caused by the wind speed of the auxiliary airflow and the effect on the droplet migration were coupled, and the two ultimately affected the droplet deposition performance. Studying the effect of the coupling ratio of the two on the deposition performance can provide guidance for the optimization of air-assisted spray parameters and the improvement of spray patterns. Taking cotton in the full blooming period as the research object, and the different effects of the decoupling of the two on the droplet deposition behavior were analyzed by designing a decoupling test plan. Firstly, the deformation of cotton branches and leaves under wind load was calibrated with the help of a high-speed camera, and the fitting relationship among air velocity, leaf area and deformation was obtained. Through carrying out the wind load deformation test of the fake blade, it was verified that the wind load deformation error of the fake blade and the real blade was basically less than 17%. The plan of using the simulated cotton model to be applied to the air-assisted spray test was determined. Then, according to the 3/8 rule of the branch and leaf configuration of cotton growth and development, a cotton model of Scheme 1 in which the canopy porosity can be changed by wind load was built. The data of the airflow field in the cotton canopy was measured, and the deformation of branches and leaves under different wind speeds was calculated. Physical means were used to fix the deformation of branches and leaves, and a Scheme 2 cotton model was formed with fixed canopy porosity after wind load deformation. The cotton branches and leaves was fixed in the natural state and the canopy porosity was kept unchanged under wind load as the cotton model of Scheme 3. Finally, for the cotton models of the three test schemes, the auxiliary air flow velocity was changed to carry out air-assisted droplet deposition experiments. The test results showed that the migration effect of airflow on droplets was more favorable to the deposition behavior of droplets in the canopy than changes in canopy porosity. The effect of air flow on the movement of droplets increased the droplet deposition rate by 39.81%, and the change in canopy porosity increased the droplet deposition rate by 10.52%. The droplet transport channel formed by the increase of canopy pores was more conducive to the uniform distribution of droplets in the canopy than the transport effect of airflow on the droplets. The increase in the porosity of the canopy increased the deposition uniformity by 42.71%, and the transport effect of the air flow on the droplets increased the deposition uniformity by 1.10%. This decoupling method can provide a reference for the design of spray patterns for different crop canopy porosity changes. © 2021, Chinese Society of Agricultural Machinery. All right reserved.
引用
收藏
页码:117 / 126and137
相关论文
共 27 条
  • [11] MUSIU E M, QI Lijun, WU Yalei, Spray deposition and distribution on the targets and losses to the ground as affected by application volume rate, airflow rate and target position, Crop Protection, 116, pp. 170-180, (2019)
  • [12] LIU Dongmei, YANG Hangxu, ZHOU Hongping, Et al., Droplet deposition performance of low-capacity profiling spray in densely planted dwarf tea plantation, Transactions of the Chinese Society for Agricultural Machinery, 50, 10, pp. 96-105, (2019)
  • [13] WANG Jun, DONG Xiang, YAN Herong, Et al., Experiment on spraying performance of air-assisted boom sprayer in corn field, Transactions of the Chinese Society for Agricultural Machinery, 46, 7, pp. 79-84, (2015)
  • [14] LU Xiaolan, FU Ximin, WU Ping, Et al., Influence of spray operating parameters on droplet deposition, Transactions of the Chinese Society for Agricultural Machinery, 42, 6, pp. 70-75, (2011)
  • [15] MIRANDA-FUENTES A, MARUCCO P, GONZALEZ-SANCHEZ E J, Et al., Developing strategies to reduce spray drift in pneumatic spraying in vineyards: assessment of the parameters affecting droplet size in pneumatic spraying[J], Science of the Total Environment, 616, pp. 805-815, (2018)
  • [16] ZHOU Liangfu, FU Ximin, DING Weimin, Et al., Design and experiment of combined disc air-assisted orchard sprayer, Transactions of the CSAE, 31, 10, pp. 64-71, (2015)
  • [17] DE COCK N, MASSINON M, SALAH S O T, Et al., Investigation on optimal spray properties for ground based agricultural applications using deposition and retention models[J], Biosystems Engineering, 162, pp. 99-111, (2017)
  • [18] MUSIU E M, QI Lijun, WU Yalei, Evaluation of droplets size distribution and velocity pattern using computational fluid dynamics modelling, Computers and Electronics in Agriculture, 164, (2019)
  • [19] CHEN Rongkang, Study on canopy porosity change of high canopy density under auxiliary airflow, (2017)
  • [20] WU Minqing, Study on the deformation of cotton canopy stems and leaves and the droplet deposition law under assisted airflow, (2019)