摘要
传统的变压力式施药系统只进行基于植保机械行进速度的一次变量控制施药,在农药喷施过程中将农田作物冠层状态看作不变值,忽略叶片随时段的迁移发生的面积和倾角变化,未能把叶倾角作为参数在控制系统中体现,同时参与系统喷药控制。传统施药实践表明,在对大豆等叶运动(趋光运动)能力较强的作物进行大田施药时,传统的变量施药方法会使农药利用率与植保效果无法兼顾。针对以上问题,在传统压力式变量施药技术基础上,根据作物叶面积指数以及叶片倾角随时间的周期性变化规律,构建不同叶倾角叶片三维模型,把大豆叶片的叶倾角的值作为的一个参数,添加到二次变压力施药的控制系统中,运用CFD技术进行喷雾流场仿真建模,以增加不同叶倾角作物的表面雾滴沉积率为目的,在不同压力与流量下对不同叶倾角叶片进行的喷雾仿真试验,通过液相体积数分析,找出有效的喷雾压力和流量,以及变量施药系统二次控制的压力与雾滴沉积率的关系。基于仿真试验结果,设计了新型变压力式变量施药系统。根据叶片叶倾角对应的时段采用的喷药压力和流量,在6∶00-10∶00时段进行大田变量喷雾试验。试验结果表明:大豆叶片雾滴覆盖率全程处于30%~40%之间,满足植保喷雾效果,有效避免了传统施药过程中的农药浪费。
The traditional variable pressure application system only carries out the one-time variable control application based on the traveling speed of plant protection machinery.In the process of pesticide application,the state of field crop canopy is regarded as a constant value,and the changes of area and dip Angle of leaves with time are ignored,the leaf dip Angle is not a parameter in the control system.The traditional variable application method could not take into account the utilization rate of pesticide and the plant protection effect in the field application of soybean and other crops with strong leaf movement(phototaxis) ability.Aiming at the above problems,on the basis of traditional pressure variable application technology,according to the crop leaf area index and the periodic change rule of leaf dip over time,three-dimensional leaf models with different leaf dip angles were constructed.The value of soybean leaf dip Angle was added as a parameter to the control system of secondary pressure variable application control system,and the spray flow field simulation modeling was carried out with CFD technology.In order to increase the droplet deposition rate on the surface of crops with different leaf angles,the spray simulation tests were carried out on the leaves with different leaf angles under different pressures and flows,and the relationship between effective spray pressure,flow rate,secondary control pressure of variable application system and droplet deposition rate was found out through the liquid phase volume number analysis.Based on the results of simulation experiment,a new variable pressure application system was designed.Using the spray pressure and flow rate of the time corresponding to the dipangle of leave,the field variable spray test was conducted from 6∶00 am to 10∶00 am.The results showed that the coverage rate of soybean leaves was between 30%-40%,which met the plant protection spray effect demard,and effectively avoid the waste of pesticides in the traditional application process.
作者
吴朝阳
解法旺
陈书法
孙启新
孙传东
WU Zhao-yang;XIE Fa-wang;CHEN Shu-fa;SUN Qi-xin;SUN Chuan-dong(School of Mechanical Engineering,Nantong Universiy,Nantong Jiangsu 226019,China;Graduate School,Jiangsu Ocean University,Lianyungang Jiangsu 222005,China;Jiangsu Dahlis Machinery Manufacturing Co.LTD,Lianyungang Jiangsu 222005,China)
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2023年第1期90-97,共8页
Journal of Shenyang Agricultural University
基金
中国现代农业产业技术体系计划项目(CAR49)
江苏省种业振兴工程计划项目(JBGS[2021]034)。
