Question about heat sinks...

y0ssar1an22

I hope this is in the correct place, and if not I would appreciate if a mod moved it to a more suitable location.

I am currently working on a project and am having difficulty getting my head around this, so am seeking guidance/advice.

What should I be looking for to accomplish the following:

1 material that will take heat away from a heat source, and transfer that heat to another material (heat sink?).
What are these 2 things called and could you give me some examples of materials please.

Thanks

Sir Arthur Daley

y0ssar1an22 wrote: »

I hope this is in the correct place, and if not I would appreciate if a mod moved it to a more suitable location.

I am currently working on a project and am having difficulty getting my head around this, so am seeking guidance/advice.

What should I be looking for to accomplish the following:

1 material that will take heat away from a heat source, and transfer that heat to another material (heat sink?).
What are these 2 things called and could you give me some examples of materials please.

Thanks

Copper would be a good material to take heat away from a source and transfer it to a heat sink or rad, a laptops cooling system is a good example with assisted fan for further cooling.

y0ssar1an22

WikiHow wrote: »

Copper would be a good material to take heat away from a source and transfer it to a heat sink or rad, a laptops cooling system is a good example with assisted fan for further cooling.

just to clarify....copper is a good material to transfer heat to another source (does the copper itself heat up?). What would copper be referred to in that case?
And what material could you use as the heat sink?
Thanks

Sir Arthur Daley

y0ssar1an22 wrote: »

just to clarify....copper is a good material to transfer heat to another source (does the copper itself heat up?). What would copper be referred to in that case?
And what material could you use as the heat sink?
Thanks

The copper would heat, how hot depends on how much its transferring, you would call the copper the transfer system, aluminum alloy is the simplest form of a heat sink.

milltown

What you seem to be asking about is conduction. The copper would transfer the heat by conduction away from one place to another. The copper being the conductor. The problem with this method is, unless you remove the heat by another means at the other end, there will just be a tendency for the temperature to equalise across the whole "circuit". Without something like a fan, as Wikihow suggested, to remove the heat (actually just another method of heat transfer, called convection) there will be no temperature differential to draw the heat away from your source once it heats up.

I forget which physics law states that you can't destroy energy. All you can do is convert it or store it.

/awaits a slew of corrections

Holsten

Copper to take it away into aluminium.

Dunno the correct name.

You'd then use another form of cooling to cool the aluminium.

cast_iron

milltown wrote: »

I forget which physics law states that you can't destroy energy. All you can do is convert it or store it.

It's one of the Laws of Thermodynamics. I think the second one.

Copper would often be used to transfer the heat from source to sink (via conduction). Sink made from aluminium would be most common. The copper link between the two may not be needed.

As to where the heat goes from there, it really depends on where the sink is, ie. the surroundings. Can air circulate freely in the vicinity? If so, natural convection may be fine. If not, forced convection may be required.

Can the OP give more specific details of the area heat needs to be dissipated from?

redtelephone

Best heat conductors are gold silver copper aluminium and iron. Aluminium is often used as a heat sink because it can be easily cast into suitable shapes with cooling fins etc. Copper is more flexible, so is often used to carry the heat to the heat sink.

http://www.howstuffworks.com/heat-sink.htm

whizbang

eh, water.

Lookup Watercooling for PC's. May not be your specific application, but lots of tech Info out there.

We need a better idea of temperatures, heat capacity, application before any more info will help.

y0ssar1an22

Thanks for all the reply's. Here is some more detail:

taking a laptop for example. Could you sit it on copper to take the heat away from the laptop? And have the copper sitting on a slab of aluminum. So you would essentially have a passive heat transfer system. With copper continually cooling down (or at least extracting heat) laptop, and aluminum continually cooling down copper.
If I understand correctly the copper can transfer heat quickly, and the aluminum can store a lot of heat. Would this allow aluminum to naturally cool down (via convection) before it too overheats.

whizbang

In this case, ultimately the heat is transferred to the surrounding air.

So the medium to long term, the heat transfer depends on the surface area of the air/metal junction, but also, the airflow rate and the differential temperature.

The problem with the laptop is, its on top of the heatsink, and the heatsink is insulated by whatever its resting on, the surface area is mostly dependant on the size of the laptop, so in the end, you are still restricted by airflow.

Heat sinks are used for engine cooling (radiator) also electronic stability on a smaller scale.




I think this is what you have in mind though.