Droplets Evaporation Rule Of Exploration And Evaluation Of Several Aviation Spray Adjuvants

In recent years,Plant protection machinery in our country has developed rapidly,especially represented by aviation plant protection machinery is more and more attention.Air spray because of its high efficiency,has increasingly become the first choice of prevention of plant diseases and insect pests.But as a result of air spray is easily afftected of operation conditions and environmental factors,there are serious problems about evaporation,great lost of drift,the low deposition and so on.There are relevant research shows that adding spray adjuvants in the liquid can obviously improve situations in spray process of unmanned aerial vehicle?uav?,such as evaporation,drift,absorption difficultly,to improve the spraying effect of uav.Domestic existing part aviation spray adjuvants,but there is no dig into comparison and evaluation of aviation spray adjuvants.In this paper,we preliminary studied the affects of surface tension,wettability,contact angle of rice leaf and droplet diameter after adding different kinds of aviation adjuvants:hydroxypropyl guar gum,glycerin,Greenwet360,Greenwet720,Silwet DRS60,ATPLUS DRT-NIS,ATPLUS-HS-500-LQ-?AP?into water.Then we used optical contact angle measuring device in pendant drop mode,at the temperature 25 ? and 33 ?,detected the effects of five aviation spray adiuvants?hydroxypropyl guar gum,glycerol,Greenwet360,Greenwet720 and SilwetDRS60?on the evaporation inhibition of spray droplet.Under the condition of wind tunnel tested several adjuvants on the influence of the droplet drift.On this basis,in the field,we used MG-type 1 eight rotor UAV at XingHua rice paddies spraying to test the affect of droplet deposition distribution after adding 0.5%,1.0%DRS60.This paper is supposed to select a good aviation spray adjuvant which can resist evaporation,drift,and has good wettability,thus reduce phytotoxicity problem,raising the pesticide utilization ratio of aviation plant protection.The conclusions are as follows:Adding 1%Greenwet360,1%DRS60 in water,could significantly make surface tension decreased respectively 52.12,50.96 mN/m.Corresponding to the ground,1%Greenwet360,1%DRS60 performanced the best wettability.Adding 0.02%,0.05%,0.02%and 0.05%DRS60 were all significantly decreased in its contact angle on the rice leaf.0.5%Greenwet360 could make the droplets in rice leaves spread completely.Adding different concentrations glycerin,DRT-NIS?MSO-HS 500?Greenwet720 can't significantly affect the surface tension value.Indoor using homemade spray system to spray?installing centrifugal nozzle?under 0.3 Mpa pressure.The results demonstrated that DRS60 and Greentwet360 exhibited good effect.Among them,after adding 0.5%DRS60,D_v50 reached to 165.5?m,it increased 45.3?m compared without adjuvant.After adding 0.5%Greenwet360,Dv 50 reached to 148.5?m,it increased 28.2?m compared without adjuvant.Using optical contact angle measuring device in pendant drop mode,the effect of five aviation spray adiuvants?hydroxypropyl guar gum,glycerol,Greenwet360,Greenwet720 and SilwetDRS60?on the evaporation inhibition of spray droplets was investigated.The results demonstrated that DRS60 and Greentwet360 at 25? and 33? exhibited good inhibitory effect.Among them,0.05%DRS60 had the best performance with the inhibition rate of 75%and 60%,respectively.While for 0.05%Greenwet360,the inhibition rates were 62.5%and 47%,respectively.The inhibition rate of 0.5%?1%hydroxypropyl guar gum and 1%Greenwet720 at 33 ? increased by 28%,28%and 27.5%than that at 25 ?.Using different adjuvants under the condition of wind tunnel?choose teejet11001 nozzle?affect the droplet drift.The results demonstrated that DRS60 and Agrospread910 exhibited good effect.Nozzle distance 0.5-lm range,droplets coverage of five adjuvants as follows:DRS60>Agrospread910>Greenwet720>Greenwet360>NIS.Nozzle distance 2-range,droplets coverage of five adjuvants as follows:Greenwet360<NIS<Greenwet720<Agrospread910<DRS60.Results showed that when adding additives concentration increased from 0.5%to 1%each measuring point cloud droplets coverage increased which showed that droplet diameter increased as the concentration of additives added while hadn't performance good effect to the droplet drift.Using MG-1 type eight rotors UAV in XingHua rice paddies spraying kasugamycin.Experimental results showed increased after adding DRS60.And droplet deposition density in unit square centimeter and concentration of additives added were positively correlated.DRS60 with concentration of 0.5%,1%,the droplet deposition density reached to 34.93,37.62 per unit square centimeter respectively,increased 3.44,6.13 per unit square centimeter respectively compared to without adding adjuvants.