接触面温度对表面液滴蒸发过程的影响

详细研究了不同接触面温度对液滴蒸发过程的影响.通过分析液滴中间平面的粒子图像,首先阐述了接触面温度对液滴内漩涡流动的影响,并指出液滴周围水汽的凝结过程对液滴底部成像的影响.然后计算了不同接触面温度条件下液滴的量纲一体积与接触角随时间的变化曲线.结果表明,随着接触面温度的降低,液滴的量纲一体积和接触角减少的速度都变慢,在接触面温度较低的时候(例如5°C),液滴的量纲一体积和接触角都因空气中水汽凝结过程的影响而增大.

The Effect of Surface Temperature on Droplet Evaporation

In the present study,the effects of the surface temperature of subtract on the evaporation process of water droplets are investigated experimentally.By analyzing the acquired images of the tiny tracer particles inside the water droplets,the effects of surface temperature on the Maragoni flows inside the droplets and the time evolutions of the contact line,contact angle and the volume change of the droplets during the evaporation process were revealed clearly and quantitatively.The measurement results show that as the surface temperature of substrate decreases,the reducing rates of the droplet volume and contact angle become slow.However,when the surface temperature becomes relatively low(e.g.,T<5 ℃),the droplet volume and contact angle are found to increase with time due to the condensation process.