Heat generation is an issue that affects a lot of modern technology.
Historically, many things simply havent produced enough heat for it to be an issue to get rid of.
The story is different with modern microelectronics, though.
Heat production is a real issue that limits performance.
One key to continuing to increase performance is to improve cooling solutions.
The main goal in cooling is to reduce the temperature of the thing being cooled.
To do that, the heat must be transferred elsewhere, as demanded by the second law of thermodynamics.
All three of these have different and vital effects.
Metal is a fantastic conductor of heat.
Metal things can heat up quickly and cool down quickly.
Both happen because metal is excellent at conducting heat.
you could observe the same in reverse by holding the same spoon under the cold tap.
This is the same reason it takes longer to boil a pot that you put more water in.
Theres more water or metal in this case to heat up.
Critically though, the end goal isnt to heat up the heat sink.
Its to heat up the air around the heatsink because the air can quickly move away.
Thankfully, theres a lot of air in the atmosphere to heat.
So why use metal?
Why not just heat the air directly?
Surface Area
The surface area is vital for the efficient transfer of heat.
The most comparable example is trying to dry clothes.
To get around this, it’s crucial that you increase the surface area of your chunk of metal.
Combining Factors
Combining all three of these factors is critical to making a good cooler.
A heat sink is simply something into which heat can essentially be poured.
There are two types of heatsinks, though, passive and active.
While active heat sinks are more common, passive heat sinks are more interesting.
Passive heat sinks only use the above techniques to transmit heat.
They rely purely on natural cooling.
Physics lends a helping hand thanks to gravity and convection.
This, however, makes it hard for air to flow over the surface you want to cool.
You need that airflow to carry the heat away.
You also need to align your sheets so that air in your cooler can rise due to convection.
Heat only transfers from hot items to cold things.
The speed at which it does so depends on the temperature difference between the two.
If you might avoid heating up the air around a passive heat sink, you should.
this is by it heating air, and the hot air rising away.
Passive heat sinks are generally large and have a lot of surface area.
The main benefit is that passive heat sinks are silent and have no moving parts.
