ABSTRACT
In the present study, the effects of the surface morphology and surface hydrophobicity on droplet dynamics and condensation efficiency are investigated using the lattice Boltzmann method. Different surface morphologies may have different condensation heat transfer efficiencies, resulting in diverse condensation rates under the same conditions. The obtained results show that among the studied morphologies, the highest condensation rate can be achieved for conical micro-structures followed by the triangle micro-structure, and the columnar micro-structure has the lowest condensation rate. Moreover, it is found that when the surface micro-structure spacing is smaller and the surface micro-structure is denser, the condensation heat transfer between the surface structure and water vapor facilitates, thereby increasing the condensation efficiency of droplets. Furthermore, the condensation process of droplets is associated with the surface hydrophobicity. The more hydrophobic the surface, the more difficult the condensation heat transfer and the longer the required time for droplet nucleation. Meanwhile, a more hydrophobic surface means that it is harder for droplets to gather and merge, and the corresponding droplet condensation rate is also lower.
KEYWORDS
PAPER SUBMITTED: 2021-05-06
PAPER REVISED: 1970-01-01
PAPER ACCEPTED: 2021-07-17
PUBLISHED ONLINE: 2021-10-10
THERMAL SCIENCE YEAR
2022, VOLUME
26, ISSUE
Issue 4, PAGES [3505 - 3515]
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