对冲喷头设计与雾化试验

doi:10.11707/j.1001-7488.20190110

摘要/Abstract

摘要： [目的]针对植保机械扇形喷头雾滴粒谱较宽、雾滴粒径均匀度较差等不足，基于射流和撞击流耦合作用原理，提出一种新型喷头结构方案，以改善喷头雾滴粒径均匀性和雾滴谱。[方法]采用快速成型制造技术的光敏液相固化成型（SLA）工艺，选用C-UV9400立体光造型树脂材料，制造出喷头终端喷孔出水口形状相同、出水口孔径d₁=1 mm、切槽角α=30°的扇形喷头和新型对冲喷头；利用喷头雾化性能测试系统检测2种喷头的雾滴粒径和雾滴分布情况，使用分布跨度评价雾滴粒径均匀性。[结果]在距喷头终端喷孔出水口100 mm处，喷施压力在0.3~0.8 MPa范围内变化时，扇形喷头和新型对冲喷头的分布跨度分别在1.65~1.82和1.07~1.23之间，分布跨度小表明雾滴粒径均匀性好、雾滴谱窄，且从测得的雾滴分布图发现，新型对冲喷头的雾滴分布较集中；当喷施压力大于0.6 MPa时，扇形喷头雾滴粒径变化趋向稳定，而新型对冲喷头雾滴粒径随喷施压力增大还能不断减小，表明新型对冲喷头具有调压范围宽的良好调压特性；撞击后会形成较大雾滴，较大雾滴并有一定速度具备较好的穿透性能和抗飘移能力；为使喷头达到较佳的病虫害防治效果，建立了喷头雾滴粒径多项式回归模型，为喷头选用提供依据。[结论]基于射流和撞击流耦合作用的对冲喷头具有雾滴粒径均匀性较好、雾滴谱较窄、调压范围宽和抗飘性较强的特点，可为开发精准施药植保机械装备提供技术支持。

关键词: 对冲喷头, 撞击流, 雾滴粒径, 粒径均匀性, 调压特性

Abstract: [Objective] In view of the deficiencies that spray droplets were wider in flat-fan nozzle of plant protection machinery, and particle size uniformity were insufficient, a new type of nozzle structure based on the coupling of jet and impinging jets was proposed to improve the spray droplet size uniformity and the droplet spectrum.[Method] Using photosensitive liquid phase curing molding process of rapid prototyping manufacturing technology and C-UV9400 stereoscopic light modeling resin material, the flat-fan nozzle and impinging nozzle were produced which had the same exit shape, exit diameter(d₁=1 mm) and groove angle(α=30°). The droplet size and droplet distribution of the two kinds of nozzles were obtained according to the test system for atomizing performance of nozzle, and the uniformity of the particle size was evaluated in terms of the international criteria for distribution span.[Result] At the position 100 mm away from the nozzle exit, when the spraying pressure changed within the range of 0.3-0.8 MPa, it was found that the S value of the distribution span of flat-fan nozzle and impinging nozzle were respectively between 1.65-1.82 and 1.07-1.23, in which the smaller S value stands for better uniform and narrower spectrum, and the spraying performance test system showed that the droplet were more concentrated; the droplet size of flat-fan nozzle tended to be stable when the spraying pressure was greater than 0.6 MPa, and the droplet size of impinging nozzle decreased with the increase of spraying pressure, which indicated that the impinging nozzle had a variable pressure regulating performance with wide pressure regulating range; large droplets will be formed after impact, and larger droplets with a certain speed had better penetration performance and anti-drift ability. Besides, a multiple regression model of droplet size was established to provide a basis for selecting nozzle to achieve a better pest control.[Conclusion] The impinging nozzle based on the coupling of jet and impinging jets had the characteristics of improving particle size uniformity, narrow droplet spectrum, wide range of pressure regulation and better anti-drift ability. It can provide technical support for developing precision sprayer.

Key words: impinging nozzle, impinging jets, droplet size, particle size uniformity, pressure regulating performance

中图分类号:

S491
TH122

董福龙, 周宏平, 施明宏, 茹煜, 易克传. 对冲喷头设计与雾化试验[J]. 林业科学, 2019, 55(1): 81-88.

Dong Fulong, Zhou Hongping, Shi Minghong, Ru Yu, Yi Kechuan. Design and Atomization Test of Impinging Nozzle[J]. Scientia Silvae Sinicae, 2019, 55(1): 81-88.

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