ISSN Online: 2377-424X
ISBN Print: 978-1-56700-474-8
ISBN Online: 978-1-56700-473-1
International Heat Transfer Conference 16
A COMPUTATIONAL MODEL FOR CONDENSATION HEAT TRANSFER ANALYSIS AT BIPHILIC INTERFACE
Sinopsis
Biphilic surfaces with heterogeneous wettability and hierarchical topography have demonstrated significant enhancement in condensation heat transfer by mutual benefit in in droplet nucleation and droplet shedding. To investigate the underlying physics of the condensation process on a biphilic surface and further explore the optimal design to achieve preferable heat transfer performance, we develop a comprehensive model that can capture the recurrent transition of filmwise-to-dropwise condensation on biphilic topographies by considering the dynamics of droplet morphology for individual droplet growth, droplet departure, and the associated droplet size distribution. The numerical results indicate that the varying droplet contact angle and stepwise increase of the droplet contact base area substantially influence the droplet growth and the coalescence-induced droplet departure during the condensation process, and therefore contribute directly to the overall heat transfer enhancement. The modeling results are validated by comparing with the heat flux measured in a custom-designed environment chamber. The developed model not only reveals the physics of condensation on biphilic surfaces but also provides important guidelines for the design and optimization of biphilic topographies for high heat flux applications.
PALABRAS CLAVE:
Condensation, Heat transfer enhancement, Biphilic surface, jumping droplets, heat transfer model