基于LPM的摇臂式喷头水滴分布试验研究

为了研究旋转式喷头水滴直径、速度及动能的分布规律,采用激光雨滴谱仪(Laser Precipitation Monitor,LPM)对3026B型摇臂式喷头分别在0.15,0.20,0.25,0.30,0.35 MPa这5种工作压力下进行了室内无风水滴分布试验,并根据最小二乘法原理建立了水滴分布数学模型.试验结果表明:3026B型摇臂式喷头的喷洒水滴直径与喷头距离之间总体上呈指数函数分布;直径在1~3 mm的水滴在5种压力下占整个喷洒区域的频率分别为56.80%,64.35%,72.14%,61.72%,40.17%;距喷头不同距离的水滴累积频率曲线斜率随着压力的增加逐渐减小;水滴速度与直径呈对数函数分布;水滴动能与喷头距离呈指数函数分布,其相关系数在0.8以上.压力对近处水滴直径、速度及动能的分布规律影响较小,对远处的影响较大.

Droplets distribution research of impact sprinkler based on Laser Precipitation Monitor

In order to research the droplet distribution of rotating sprinkler,droplet diameter and droplet velocity of 3026B impact sprinkler were measured by Laser Precipitation Monitor. The experiment was applied under the operating pressure of 0.15,0.20,0.25,0.30,0.35 MPa with no wind. Droplets mathematical models were built based on the method of least squares. Results showed that the relationships between droplets diameter and the distance along the sprinkler were indicted by exponential function,except the droplets at 4 meter from the sprinkler. The droplets frequency were up to 56.8%,64.35%,72.14%,61.72%,40.17% respectively, under the operating pressures of 0.15,0.20,0.25,0.30,0.35 MPa. The droplets frequency was the ratio of the droplets volume that diameter between in 1-3 mm to all the droplets in the whole spray area. The slope of droplets diameter cumulative frequency curve decreased with the operating pressure increasing. The relation between droplet velocity and droplet diameter were indicted by linear function model built. There were exponential relationships between droplet kinetic energy and the distance along the sprinkler.