Developing Hierarchical Hybrid Surfaces for Enhanced Condensation Heat Transfer

Dropwise condensation, a multi-scale phenomenon that allows for efficient removal of heat by phase change, is encountered widely in the energy and thermal industries. Textured superhydrophobic surfaces appear to be an ideal solution for enhanced heat transfer because of their excellent ability in sustaining stable spherical droplets. However, to date, it is not clear how the surface roughness directly impacts condensation heat transfer, partially due to the challenges in capturing the microscopic condensation dynamics (droplet nucleation, coalescence, and removal) and relating these pictures to macroscopic measurement (heat transfer rate). Our aims are to elucidate the effects of surface roughness on dropwise condensation and to develop novel hierarchical hybrid surfaces that promote droplet condensation for prolonged periods of time and continuous droplet removal. The success of the project will provide important insights into the design of novel materials leading to cost savings and improved performance in thermal and energy systems.