Variation characters of droplet coverage area in leaf droplet water uptake process
GAO Jian-Min-1, 2 , AN Gui-Ren-1, LIU Chang-Jian-1, HUANG Gui-Zhen-1
(1.Key Laboratory of Modern Agricultural Equipment and Technology，Ministry of Education & Jiangsu Province，Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.USDAARS, Application Technology Research Unit, Wooster, OH 44691, USA)
In order to provide useful data for theoretical investigations into aeroponics, foliar fertilization and plant protection equipment development, the process of plant tissue absorbing droplet was conducted. A chamber with controlled environment (100% relative humidity and 20 ℃ temperature) was designed to observe the change in the coverage area of a droplet on a leaf with time. To eliminate the influence of droplet evaporation, three droplets respectively with 238.77, 229.92 and 212.60 μm diameters were employed to verify droplet evaporation rates. The evaporation rates of three droplets were 1.43%, 2.8% and 3.1% at the interval of 600 s respectively. Two droplets with the diameters of 340 and 540 μm were employed to conduct the droplet foliage uptake experiments. The experimental outcomes suggest that the change rate of coverage area of droplet depends on the position where a droplet is dripped and the time elapsed when the droplet is on the foliage.
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