Extended surfaces increase heat transfer area.
Fins extend surface area to enhance heat transfer. Fin efficiency η_f=tanh(mL)/(mL) with m=√(hP/kA_c). Used on heat sinks, engine cylinders and radiators. Optimal fin geometry balances conduction along fin and convection from surface.
An aluminium heat sink with 20 fins dissipates tens of watts more than a flat plate.
Fins extend a surface to increase heat transfer, which is important for air-cooled engines, transformers and electronics.
Extended surfaces increase heat transfer area.
Fins extend a surface to increase heat transfer, which is important for air-cooled engines, transformers and electronics.
They add surface area in contact with the fluid, which increases the total heat transfer when the fluid heat transfer coefficient is low.
Fin efficiency falls with length and low conductivity, so very long or thin fins add less benefit than expected.
Typical applications include designing the fins of a motorcycle engine for air cooling, adding a heat sink to a power transistor and estimating the effect of adding fins to a small electronics enclosure.
Study "View factors" first (topic 90 of 105 in Thermodynamics & Fluids). It covers the groundwork this topic builds on.
Fin effectiveness. Thin fins with spacing. Material with high k.
An aluminium heat sink with 20 fins dissipates tens of watts more than a flat plate.
The next topic is "Transient conduction", which builds directly on this one.
It is classed as Advanced in Thermodynamics & Fluids (topic 91 of 105). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Thermodynamics & Fluids.
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