顶喷与侧喷组合喷雾系统的吊杆碰撞与沉积试验研究

发布时间：2018-09-18 16:49

【摘要】：喷杆式喷雾技术是现今最主流的一种植保作业方式,喷杆的多样化也是一种社会趋势。我国对喷杆喷雾技术有了广泛的关注,但喷杆喷雾机主要应用水平杆喷雾技术,结构单一化,需要更加多样化结构的喷杆来应用到实际中去,并结合新型的静电喷雾技术,这样才能更大程度上提高施药作业效率。针对以上的这种现象,本人在熟读了相关文献并结合实际情况设计了一种顶喷与侧喷结合的组合式静电喷雾试验装置,该装置结合了顶喷与侧喷两种方式,并与静电喷雾技术相结合,实现了一种多方位的施药作业技术,为植保行业以后的发展提供更好的依据。本文主要研究工作和结论包括以下几个方面:(1)顶喷与侧喷结合的组合式静电喷雾试验系统的设计设计和开发了顶喷与侧喷结合的组合式静电喷雾试验系统,主要包括喷杆结构的设计。其中组合式喷杆上的弹簧和整体尺寸的选型进行了对比和试验,选择了合适尺寸和材料的弹簧。(2)利用数值模拟方法的吊杆与枝干的碰撞研究利用仿真软件LS-DYNA吊杆与棉枝的碰撞过程进行仿真分析,对吊杆与棉枝有限元模型的建立及相关事项;利用建立好的有限元模型对一定工况下吊杆与棉枝碰撞过程进行模拟仿真,最后通过跟第四章中的吊杆碰撞实验结果的比较得出仿真模型的准确性和可靠性,通过喷头的偏移距离s的变化曲线与仿真中的喷头所在的吊杆上的位置H2312的偏移距离比较,误差值小于10%,还分析和比较了吊杆与棉枝的接触力的实际变化曲线,验证的结果是实验中力变化的趋势与仿真中的接触力的变化曲线误差在10%以内,可以相互验证。(3)组合式喷杆中吊杆碰撞试验与结果分析对吊杆的喷头偏移距离和吊杆接触力进行测量;此外还对喷头的偏移距离s和吊杆接触力F进行了两因素的拟合实验,得出在碰撞速度v和接触位置h的变化下的喷头最大偏移距离Smax的变化规律,喷头最大偏移距离Smax与碰撞速度v和接触位置h呈线性相关。还通过基于高速摄像技术的实验室的模拟实验来得到喷头的运动轨迹并得出在植株上的重喷和漏喷的区域;表明了静电喷雾结合组合式喷雾方式有效的提高了喷雾的沉积效果,静电喷雾对于提高植株中层的喷雾沉积均匀性有促进作用,减少重喷与漏喷现象。(4)沉积分布影响因素试验以第二章的喷杆喷雾系统为实验基础对各种不同的因素对喷雾沉积覆盖率和变异系数的影响。试验主要考虑了是否荷静电、喷雾压力、喷雾作业速度、喷雾高度对沉积分布的影响。采用了正交设计的实验设计方法来设计实验参数布置,且运用方差分析方法研究了静电与非静电喷雾作用下试验参数对沉积效果影响的显著性,且得出了喷雾压力、喷雾高度和作业速度在无静电坏境下和有静电环境下的最佳因素组合的具体数值为0.5mpa、350mm、1.0m/s和0.4mpa、350mm、1.0m/s。还比较了水平杆的实际应用中的沉积性能并与组合式静电喷雾结果比较。
[Abstract]:Spray bar spraying technology is the most mainstream plant protection operation mode nowadays, and the diversification of boom is also a social trend. China has paid extensive attention to spray rod spraying technology, but the spray rod sprayer mainly applies horizontal spray technology, and its structure is single. It needs more diversified structural boom to be applied to practice. In order to improve the efficiency of pesticide spraying, a new electrostatic spray technology is put forward. In view of the above phenomenon, I have read the relevant literature and combined with the actual situation, I have designed a combined electrostatic spray test device, which combines the top spray with the side spray. The device combines two ways of top spray and side spray, and with electrostatic spray technology. The combination of technology and operation has provided a better basis for the future development of the plant protection industry. The main research work and conclusions in this paper include the following aspects: (1) a combined electrostatic spray test system with top spray and side spray is designed, and a combined electrostatic spray with top spray and side spray is developed. The fog test system mainly includes the design of spray rod structure, in which the spring on the combined spray rod is compared with the selection of the whole size, and the spring of the suitable size and material is selected. (2) The collision between the hanger rod and the branch is studied by numerical simulation method, and the collision process between the hanger rod and the cotton branch is simulated by the simulation software LS-DYNA. The finite element model of suspender and cotton branch is established and related matters are analyzed. The collision process of suspender and cotton branch is simulated under certain working conditions by using the established finite element model. Finally, the accuracy and reliability of the simulation model are obtained by comparing with the experimental results of suspender collision in chapter 4. The deviation distance between the change curve and the position H2312 of the sprinkler head in the simulation is less than 10%. The actual change curve of the contact force between the sprinkler and the cotton branch is analyzed and compared. The result is that the error between the change trend of the force in the experiment and the change curve of the contact force in the simulation is less than 10%, which can be verified by each other. 3) The sprinkler head offset distance and the contact force of the suspender are measured by the collision test and the result analysis of the suspender in the combined sprinkler rod. In addition, the fitting experiments of the sprinkler head offset distance s and the contact force F of the suspender are carried out, and the variation law of the maximum offset distance Smax under the change of collision velocity V and contact position h is obtained. The maximum offset distance Smax of the nozzle is linearly related to the collision speed V and the contact position H. The trajectory of the sprinkler is obtained through the simulation experiment based on the high-speed photography technology, and the area of re sprayed and missed spray on the plant is obtained. It shows that the electrostatic spray combined with the combined spray method effectively improves the spray deposition efficiency. The electrostatic spray can improve the uniformity of spray deposition in the middle layer of the plant, and reduce the phenomenon of re injection and leakage. (4) the influence factors of the deposition distribution are tested by the spray spray system of the second chapter as the experimental foundation, and the effects of various factors on the spray deposition coverage and coefficient of variation are mainly considered. The effects of spray pressure, spray speed and spray height on the distribution of deposition are studied. An orthogonal experimental design method is used to design the layout of experimental parameters. ANOVA is used to study the effect of the experimental parameters on the deposition effect under electrostatic and non electrostatic spraying, and the spray pressure, spray height and operation are obtained. The specific values of industrial speed in the absence of static electricity and the best combination of factors under electrostatic environment are 0.5MPa, 350mm, 1.0m/s and 0.4MPa, 350mm and 1.0m/s.. The deposition performance in practical application of horizontal bar is also compared with that of combined electrostatic spray.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S49

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