High Speed Photograpic Observation of Flow Patterns during Flow Boiling in Single Rectangular Minichannel
نویسندگان
چکیده
The present study extends the range of flow patterns observed during boiling of water in a single minichannel of height 197 μm and width 1054 μm. The calculated hydraulic diameter of the channel is 333 μm. High-speed photography is used to obtain video images of the flow field. The top covers of the channels are made of Lexan to permit visual observation, while the minichannel is machined in a copper block heated with cartridge heaters . The flow patterns are studied as a function of mass flux, heat flux, and location along the flow channel length. The results provide important information regarding the boiling behavior in a single channel.
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