Heat Transfer
Science FactEvery machine makes waste heat. If you don't move it away, parts melt, batteries swell and chips slow down. That's why cooling is a whole build step!
Heat always moves from hot to cold
Heat is energy moving because of a temperature difference. It always flows from hotter things to colder things until they're the same temperature. Engineers move heat in three ways: conduction, convection and radiation.
Conduction
Conduction is heat moving directly through touching materials. Metals like copper and aluminum conduct heat very well, which is why heat sinks are made from them. Cryo Fins use conduction to pull heat out of your device.
Convection
Convection is heat carried away by a moving fluid, like air or water. Air Vents and fans use air convection. Liquid Coolant uses water, which can soak up about four times more heat than the same mass of air.
Radiation
Everything warm gives off invisible infrared light. That's how the Sun heats Earth through empty space. Spacecraft use big radiator panels to glow away their heat, because there's no air in space for convection.
- Core makes heat
- Conduction into metal fins
- Convection by air or coolant
- Radiation as infrared
- Cooler device
COOL REAL FACTS
- The James Webb Space Telescope's sunshield keeps its mirror below −220 °C.
- Computer chips can reach over 90 °C without cooling.
- Your body cools itself by sweating: evaporating water carries heat away.
SCIENCE FACT vs SCI-FI
A handheld Star Core would produce far more heat than any cooling system could remove.
TRY IT (SAFELY!)
Put a metal spoon and a plastic spoon in a mug of hot water (with an adult). After a minute, carefully feel the handles: the metal one conducts heat much faster.
REAL ENGINEER TIP
Engineers design cooling at the same time as power, never as an afterthought.
PARTS THAT USE THIS IDEA
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