The phenomenon of nature convection boiling on the outer surface of a heated hemispherical vessel surrounded by a thermal insulation structure was investigated experimentally. The objectives were to observe the behavior of the boiling-induced two-phase motion in the annular gap between the vessel and the insulation structure and to determine the flow effect on the rate of boiling. High-speed photographic records revealed the presence of violent cyclic ejection of the vapor masses generated by boiling on the vessel outer surface which resulted in a buoyancy-driven, upward, concurrent two-phase flow through the channel. When boiling was taking place at high heat flux levels, the flow was found to be three-dimensional with swirl formation. Measurements of the local boiling heat fluxes and the local wall superheats were made under steadystate boiling conditions covering the entire range of nucleate boiling with special emphasis on the high-heat-flux regime.
|Original language||English (US)|
|Number of pages||5|
|Journal||American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD|
|State||Published - Dec 1 1997|
All Science Journal Classification (ASJC) codes
- Mechanical Engineering
- Fluid Flow and Transfer Processes