Abstract:The outlet flow field of an agricultural sprayer nozzle with water as single medium fluid is studied by qualitative and quantitative experiments. Firstly, conventional shooting method using a single-lens reflex camera is used to record the outflow field of the nozzle with the spray pressure ranging from 50 Pa to 4 000 Pa. As the spray pressure increases, the shape of the jet flow at the outlet of the nozzle undergoes a process of bubble formation to corruption, as well as the development and final stabilization of the jet. Then, quantitative measurement is carried out on the outlet flow field of the nozzle with the spray pressure of 1 000—4 000 Pa, using PIV velocity measurement technique. A quantitative measurement experiment is conducted to obtain that on the longitudinal section, the outlet velocity of the nozzle increases with the spray pressure, and the velocity along the center line shows an oscillating attenuation decrease with the increase of the distance from the nozzle. At the same transverse section, with the increase of the spray pressure, the stronger the swirl strength is, the greater the flow velocity will be; while at the same spray pressure, the closer the cross section to the nozzle outlet is , the stronger the swirl strength and the greater the flow velocity will be. The experimental results in this paper show an important reference value to the design of spray nozzles and similar atomizer nozzles. It is also verified that the PIV velocity measurement technique can be used to measure the velocity field of water droplets.