A superhydrophobic surface with a contact angle greater than 160° and a sliding angle ∼2° was fabricated by a simple, low-cost chemical etching method. The evaporation characteristics of glycerol-water droplets with different viscosities on the superhydrophobic surface and the smooth surface were investigated. The results showed that the evaporation rate on the superhydrophobic surface was smaller than that on the smooth surface for the lower concentration droplets. Droplets with higher viscosity were more prone to decrease the overall evaporation rate, and this decrease occurred earlier on smooth surfaces. As the droplet concentration increased to 80% glycerol-water, the evaporation rate was higher on superhydrophobic surfaces than that on the smooth surface. In addition, the adhesion tests were conducted and showed that the superhydrophobic surface was effective in reducing the adhesion of high viscosity liquids. Consequently, the superhydrophobic surface was conducive to enhancing the heat transfer efficiency and reducing the coking problem on the heat transfer walls.

Evaporation rate; Superhydrophobic surface; Smooth surface; Glycerol-water droplet; High viscosity

Technical Institute of Physics and Chemistry, Chinese Academy of Sciences