Numerical Investigation of Bubble Behaviors in Saturated Pool Boiling

摘要

Vapor bubble behaviors under saturated pool boiling are investigated numerically and experimentally. For this, bubble dynamics such as the growth and detachment processes are simulated and discussed. The impacts of contact angle and surface structures on bubble dynamics as well as heat transfer performances are also presented. In this process, conservation equations of mass, momentum, and energy are numerically solved by commercial software ANSYS Fluent 18.1. In particular, the bubble departure diameters on flat heated surfaces are compared with theoretical model and experiments. Bubble period and wall heat flux are closely related to the velocity field around the contact line region. The numerical results also show that for a bubble growing on pillar surface, flow field around the pillar plays a significant role in the variation of bubble shape as well as an enhanced wall heat flux. Time-evolution images of single bubble evolution in pool boiling experiments are captured through a high-speed camera. Bubble behaviors from experiment and simulation show a good consistency.