High heat transfer rates through phase change.
Boiling regimes (natural convection, nucleate, transition, film) on the boiling curve; critical heat flux limits nucleate boiling (burnout). Condensation can be filmwise or dropwise (higher h). Phase change coefficients are very high, used in boilers, condensers, evaporators.
Water droplets dance on a hot pan due to the Leidenfrost effect.
Boiling and condensation transfer large amounts of heat at nearly constant temperature, which is why they are used in boilers, condensers and cooling systems.
High heat transfer rates through phase change.
Boiling and condensation transfer large amounts of heat at nearly constant temperature, which is why they are used in boilers, condensers and cooling systems.
Latent heat is absorbed at the surface as bubbles form and leave, which gives very high heat transfer coefficients.
The maximum heat flux before a vapour film blankets the surface, causing a sudden drop in heat transfer and a temperature spike.
Typical applications include designing a steam condenser for a power plant, calculating the heat transfer in a flooded evaporator in a chiller and predicting the heat flux that a boiling water pipe can handle.
Study "LMTD and NTU methods" first (topic 94 of 105 in Thermodynamics & Fluids). It covers the groundwork this topic builds on.
Pool vs flow boiling. Leidenfrost effect. Condenser design.
Water droplets dance on a hot pan due to the Leidenfrost effect.
The next topic is "Heat pipes", which builds directly on this one.
It is classed as Advanced in Thermodynamics & Fluids (topic 95 of 105). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Thermodynamics & Fluids.
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