Spray drift is a proprietary term in plant protection. It means that spraying can not cover the plant's target area accurately and evenly. It also includes the situation that it does not sink to the middle and root of the plant. Generally, droplets with a diameter of less than 200 microns are easy to drift under wind or other climatic conditions.
The crops in the target area do not reach the expected coverage concentration, resulting in poor control effect;
Uneven coverage leads to poor control effect;
The chemicals are transported to nearby fields, causing damage to nearby crops;
Surface water pollution;
Endanger animal and human health;
It may pollute the target area and nearby areas or excessive spraying in the target area will cause chemicals damage.
Many factors cause spray drift, which is mainly due to the drone itself, use method and climate.
When the spray height of the spray drone increases, and when the liquid is injected at a certain pressure, it is atomized into droplets of different sizes. The smaller the nozzle, the higher the injection pressure. The smaller the droplet, the greater the possibility of drift. However, the size of droplets will also affect the atomization effect. The smaller the droplets, the better the atomization effect, and the easier it is for plants to absorb. At the same time, the smaller the water drop, the easier it is to drift.
Therefore, the nozzle model, spraying pressure and droplet size of the spray drone should be considered in a matching way. It is not necessary to pursue the level of a single index alone, but to ensure the comprehensive effect.
When the spraying height of pesticide drone increases, the greater the wind speed, the more drifting because the wind will increase the proportion of small droplets, causing drift. So do not carry out spray operation higher than the recommended height, nor lower the ideal spray height.
The increase in flight speed may cause the spray to flow back to the previous airflow and the vortex behind the sprayer, and the sprayer catches smaller droplets that may drift. The flight speed shall also be implemented according to the manufacturer's recommendations. Different drones have different design levels, different research depth of aerodynamics and different control ability of air flow and water mist flow field. The maximum flight speed is different, and the manufacturer's recommendations agricultural drones for sale must be followed.
Generally speaking, the flight speed of pesticide drone with good aerodynamic design should not exceed 8m / s; For drones without aerodynamic design, the flight speed should not exceed 3m/s.
Pesticide drone operators should read the manufacturer's instructions before using pesticides. Because small nozzles are usually required for a small amount of agents, there is a greater possibility of drift. It is recommended to use a larger dose of agents as far as possible.