Let's say we have a turbulent flow (water at the temperature of 25 degrees Celsius) over a heated block at atmospheric pressure. Now if at the solid-liquid interface the local temperature is reached beyond 100 degrees Celsius the Nucleate boiling will start. Would it be good for the overall heat transfer rate.
My understanding says that because of bubble formation at the solid-liquid interface the effective heat transfer area will become less and hence boiling must be avoided for better heat transfer rate.
Dear Mayank, Boiling is a very complex process and the according to the best knowledge the nucleate boiling very important regime due to the high heat transfer that represented by latent heat of vaporization. when the surface temp will be above the saturation temp by about 5-7 C the nucleate boiling will be start and the most important thing at a certain condition is how to understanding the bubble dynamics (bubble departure diameter, nucleation site density, frequency of bubbles, bubble waiting time etc. what I understand from your question is that when the critical heat flux reach the transition regime will appear and here the vapor which cover the solid surface will resist the transfer of heat to bulk liquid which, in turn, minimize the heat transfer coefficient and rise the surface temp. however, it is not easy to explain how the heat transfer from solid to liquid during the nucleate regime because there are a lot of sub-phenomenon related to this mechanism such as convective, evaporative and quenching that responsible to transfer heat from solid to the bulk liquid. My best regards
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