Downwash flow structure development has been an important challenge for Unmanned Aerial Vehicle (UAV) to spray tea although the UAV spray is commonly used in crops, dominantly due to the downwash flow structure development in tea plantations more severe than those in crops. Here the UAV spray for tea cultivation is improved through the relationship between nozzle and spraying liquid, or, by choosing the most appropriate nozzle for the prescribed spraying liquid. As a preliminary step, the UAV spray has been studied under effects of downwash flow structure in hover. The six-rotor UAV with four commonly-used nozzles (VP110-02, XR110-02, FPV110-02, and KZ80-04) is used as the representative. Bifenthrin, widely sprayed for tea cultivation, is used as the prescribed spraying liquid. A three-dimensional model of nozzle & flow fragmentation is developed to estimate the nozzle performances. This study demonstrates that nozzle KZ80-04 is the most suitable for Bifenthrin in tea plantation and provides insight into designing effective UAV spray in crops.

中文翻译：

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悬停下洗流结构影响下六旋翼无人机茶园规定喷药液最适喷头


尽管无人机喷茶普遍用于农作物，但下洗流结构的发展一直是无人机喷茶的一个重要挑战，这主要是因为茶园的下洗流结构发展比农作物更为严重。这里通过喷头与喷液的关系，或者针对规定的喷液选择最合适的喷头来改进茶叶种植无人机喷洒。作为初步步骤，我们研究了悬停时下洗流结构影响下的无人机喷雾。以常见的四种喷头（VP110-02、XR110-02、FPV110-02、KZ80-04）的六旋翼无人机为代表。联苯菊酯作为规定的喷洒液，在茶叶种植中广泛喷洒。开发了喷嘴和流动碎片的三维模型来估计喷嘴性能。这项研究表明喷嘴 KZ80-04 最适合茶园中的联苯菊酯喷洒，并为设计有效的无人机农作物喷雾提供了见解。