The four horsemen of heat transferContents:

•Conduction•Convection•Evaporation•Radiation

Conduction

TOC

Heat transfer by contactRandom wigglingHot to coldFlow rate T, A, material, 1/thickness

Simulation

Insulation prevents conductionDown/SyntheticsThickness

Demo – Ice Melter blocks. Start the radiation demo.

Convection

TOC

Heat carried away by moving fluidMuch faster than conductionSurface layers

Examples:Sauna/cold lakeCar radiatorCooling fans on computersWind chillFirestorms

Windbreakers slow down convectionDemo – Heat Sinks and smoke box with candle

Evaporation

TOC

Heat transfer by phase changeCooling process

Whee!

If you always lose the fastest…

ExamplesCooling towers @ PSUSweat

Poly layers keep skin dryCotton = death

Radiation

TOC

Hot objects radiate photons (black body radiation)Heating up a pokerBonfire/barn fire/stovesThe sunFrost

Silver lined blankets/bags reflect radiation back to you

Demo – check temperatures on radiation demo