雾滴荷电特性对其沉积分布及黏附靶标的影响

Charging characteristics of droplets effect on the distribution and adhesion of droplets on target

以风送静电喷雾系统为研究对象,通过在三维坐标系下建立雾滴沉降运动及黏附受力模型,分析了静电喷雾中的荷电特征因素对雾滴沉降、沉积和黏附靶标的影响。通过开展室内树木靶标模拟喷雾试验及雾滴静态接触角和表面张力测试,分析对比了静电喷雾和非静电喷雾条件下雾滴的沉积分布效果及黏附特性。结果表明:雾滴荷电可以增加雾滴的沉降速度,并定向向着靶标运动沉降,靶标正面沉积覆盖率较非静电喷雾平均提高了24个/cm2,而且在靶标背面也有一定数量的沉积,同时静电作用可以减小雾滴与叶片的接触角,减小液滴表面张力,提高雾滴在植株表面的有效沉积率。

The wind electrostatic spraying system was as the study object, and the settlement movement of droplets and adhesion force model were established using three-dimensional coordinate system in this paper. Mechanism on electrostat-ic spray effecting droplet moving, droplet deposition and droplet adhesion characteristics were discussed. Through spra-ying of simulation of trees target test, surface contact angle and tension of droplets tests, droplet distribution and charged droplet effect on adhesion characteristics under electrostatic spraying or non-static effects of spray were analyzed. Accord-ing to the results, charged droplet could increase the settling velocity of droplets, and the droplets would run and deposited towards the target, average deposit cover rate on the front of target increased by 24 /cm2 , and there was a considerable number of deposits on the back of the target. Electrostatic spray could reduce the contact angle between the droplet and leaves, decrease gas-liquid interfacial surface tension. So it could improve effect of the droplet depositing on plant surface.