Abstract:
Nucleate pool boiling is known for its high heat transfer coefficients. Despite being
widely implemented, the prediction of nucleate pool boiling mechanisms remains complex and
single bubble heat transfer analysis is helpful to simplify the problem. Owing to the interesting
bubble behaviour during nucleate pool boiling, publications tend to focus on the bubble
dynamics while the experimental setup is only briefly discussed. Small but critical information
on the experimental setup is often omitted, which makes it challenging or even impossible to
reproduce or compare experimental data. Therefore, the purpose of this study is to provide a
systematic approach to using focused shadowgraphy for the investigation of single bubble
dynamics using R245fa. A pool boiling experimental setup has been built and equipped with
temperature, pressure and heat flux sensors, as well as a high-speed camera and light source. The
nucleate pool boiling takes place at a single cavity on a copper block. The influences of the heat
transfer surface area, light source, and diffuser films were investigated to provide a systematic
approach to the use of focused shadowgraphy for the investigation of single bubble dynamics.
