Effects of Dynamic Surface Wettability on Pool Boiling Behavior

Abstract

Wettability has been shown to play a critical role in the pool boiling behavior of a surface. In this thesis, the effects of surface wettability on boiling behavior are further examined, with a particular focus on understanding the role of dynamic surface wettability (i.e. receding contact angle, advancing contact angle, and contact angle hysteresis). Hydrophobic and superhydrophobic surfaces are shown to have favorable boiling performance if the receding contact angle of the surface is sufficiently low, contrary to previous reports that found them to be ineffective boiling surfaces when considering only the static contact angle. To explain this behavior, the roles of both the receding and advancing contact angles during boiling are clarified. Additionally, the effect of different dynamic wetting behaviors on heat transfer mechanisms during single bubble growth are established in order to develop a comprehensive, mechanistic understanding of the role of wettability during boiling.