盘芯喷嘴质量平衡

The mass balance of orchard air-blast sprayers has historically been assessed using an array of samplersto capture airborne particles. However, these methods only provide an idea of flux with no other informationwhich is pertinent to understand the movement of droplets and their potential to drift. Whiledroplet analysis for agricultural sprayers has always been conducted in a laboratory setting with the useof laser devices, a new phase Doppler approach is being explored to assess droplet spectra, velocity, andflux in outdoor field conditions. Therefore it is the objective of this study to develop a methodology andthe potential limitations for using a phase Doppler system while in a laboratory setting. Due to theexpected variability of field conditions as well as the turbulence of orchard sprayers, a computationalapproach was sought to assess flux from a single scan of a conical spray plume' s diameter. Using aconstant scanning speed of 0.0079 m/s, a disc core (D1/DC33) hollow cone nozzle was examined at 310,410, and 520 kPa pressure at five different heights (10, 20, 30, 40, and 50 cm). Computational flux wasthen compared to the actual flow rate, finding a 3.3% average error with a range of 16.9% and 4.7%illustrating a small underestimation of mass with the phase Doppler which was related to distance anddroplet frequency. Further, comparisons were also assessed including pattern/symmetry, droplet spectra,velocity, and the overall number of samples. The proposed methodology indicates potential for the use ofphase Doppler technology for in situ measurements of spray equipment using a conical-type spraynozzle, such as that of the orchard air-blast sprayer.

采用LaVision公司基于成像测量的SprayMaster和Artium公司相位多普勒粒子干涉仪对植物油的但喷嘴和多喷嘴静电雾化过程进行了全局几何参量测量和单点喷雾液滴运动的二维速度和液滴粒径测量。

采用德国LaVison公司的粒子成像测速PIV系统对喷嘴产生的跨声速流场的速度矢量场进行测量记录。测量系统由2kX2k像素CCD相机。光谱物理公司的PIV-400型双腔双脉冲激光器构成。激光器输出能量为350毫焦/脉冲。同时在远场对喷嘴产生的声场进行测量，分析研究等离子体主动控制喷嘴对湍流结构和声场的影响规律。