杂草叶片表面结构对雾滴铺展和蒸发的影响  

Influence of weed leaves surface structures on droplet spread and evaporation

作　　者：祁力钧[1,2] 王沛[1] 张建华[1] 李慧[1] 冀荣华[3] 王俊[4] 

机构地区：[1]中国农业大学工学院,北京100083 [2]现代农业装备优化设计北京市重点实验室,北京100083 [3]中国农业大学信息与电气工程学院,北京100083 [4]中国农业机械化科学研究院,北京100083

出　　处：《排灌机械工程学报》2012年第3期335-340,共6页Journal of Drainage and Irrigation Machinery Engineering

基　　金：农业部行业科技专项(201203025);中国农业大学研究生创业专项(2012YJ262)

摘　　要：为了揭示不同表面结构的杂草叶片上雾滴的铺展和蒸发情况差异,设计试验研究了0.5%草甘膦在含有系列体积分数有机硅助剂的情况下,选择228,288μm两种粒径雾滴,分别沉积于毛刺、蜡质、粗糙等3种结构叶片表面时的铺展与蒸发情况.试验过程由数码摄像机记录,以获取雾滴完全蒸发所需的时间.并使用Matlab图形处理工具箱对视频中表征雾滴最大铺展面积的数字图像作分割处理,计算雾滴最大铺展面积.结果显示,粒径相同的情况下,在同一结构的叶片表面,雾滴所含有的有机硅助剂体积分数与雾滴的铺展面积呈正相关,而与雾滴的蒸发时间呈负相关.粒径大小相同、含有机硅助剂体积分数相同的雾滴在毛刺叶片表面的铺展效果最好,而蒸发最快;雾滴在蜡质叶片表面铺展面积与蒸发时间受有机硅体积分数变化的影响最为明显;在粗糙结构叶片表面,粒径较小的雾滴受其'沟壑'结构影响较难铺展,而粒径较大雾滴的铺展受'沟壑'结构影响不明显.In order to reveal the difference in droplet spread and evaporation of the weed leaves with different surface structures, a series of experiments were conducted in this paper. The spray liquid was 0.5% glyphosate, the additive was organic silicon in a series of concentrations, and the sizes of tested droplets were 228 and 288 μm. The tested weed leaves had three surface structures, namely hairy, waxy and rough. The experimental evaporation process was recorded by a digital camera, so that the evaporation time and the image of maximum droplet spread area could he read from the video. The digital images of maximum spread area were segmented by using the Image Processing Toolbox of Matlab ; eventually the size of the spread area was obtained. The experiment results indicated that increasing additive concentration led to an expanded spread area and a reduced evaporation time for the same leaf and droplet size. For the same droplet size and additive concentration, hairy leaves showed a largest spread area and a shortest evaporation time. The additive concentration exhibited most significant influence on spread and evaporation time when a droplet was on a leaf with waxy surface. For a leaf with rough surface, the grooves on the surface made the droplets in small size be spread relatively hard; for the droplets in large size, however, the groove structure showed less dominated effect on the spread area.

关 键 词：叶面结构 铺展面积 蒸发时间 有机硅助剂 雾滴大小 

分 类 号：S275.5[农业科学—农业水土工程] S48[农业科学—农业工程]