摘要
由于冲蚀磨损对喷雾质量产生影响,造成喷头磨损失效。通过对扇形雾喷头球头处固体颗粒的运动状态、边界层上颗粒受力、运动速度和攻角的分析,解释了扇形雾喷头的冲蚀磨损机理。并建立了扇形雾喷头球头处材料流失体积与攻角的关系式。结果表明,在扇形雾喷头处,当固体颗粒冲击位置的轴向尺寸小于其轴向临界尺寸时,攻角随轴向尺寸的增加而增大;反之,攻角随轴向尺寸的增加而减小。分析发现,扇形雾喷头喷口处磨损程度随喷头内表面轴向尺寸的增加而增加。在扇形雾喷头喷口短轴处,轴向尺寸最大,固体颗粒的攻角最小,磨损最严重。并通过喷头冲蚀磨损试验,试验结果与理论分析一致。该文对分析喷头磨损规律,计算磨损率和磨损失效预测提供了基础依据。
The problem of spray quality of nozzle affected by erosion wear can cause the flat-fan spraying were invalid. The solid particles＇ properties on its motion, the forces, the kinematical velocity and the attack angle of the particles in boundary-layer were discussed. Then the hydraulic abrasion mechanism of the flat-fan spraying nozzles was analyzed. The volume losses of nozzles material relationship was established with the attack angle change of the spherical-top of flat-fan orifices. It was indicated that the attack angle increased with axial size increasing, when axial size of solid particles impact position was less than its critical dimension, on the contrary the attack angle decreased with axial size increasing at fan-shaped spraying nozzle. Wear degree of fan-shaped spraying nozzle increased with axial size of nozzle inner surface increasing. And the most serious wear was in the minor-axis of the spherical-top of flat-fan orifices because the least attack angle. Finally, the theoretical analysis was verified through erosion wear test of the flat-fan spraying nozzles. The results provide a reference for analyzing wear characteristics, calculating wear rate and forecasting erosion loss of the flat-fan nozzles.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2012年第12期18-23,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家"十一五"科技支撑计划(2006BAD08A12)
国家林业局"948"项目
关键词
喷头
受力分析
冲蚀磨损
扇形雾
攻角
nozzles, stress analysis, abrasion, flat-fan spraying, attack angle
