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Suppose I have a 20x20x20 c"m plastic box where the top cover is open.

On the top cover there is a fan ( 20x20 cm) which suppose to cool a cpu which is in the box .

At the bottom there is a CPU which is getting warm.

Now - in order to cool the CPU - I have 2 options :

  • put the fan to suck air from the box towards outside
  • put the fan to push air from outside towards the box.

Final goal :

Max - Cooling the cpu.


Which is the preferred approach ?

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closed as off-topic by jinawee, Brandon Enright, David Z Apr 27 '14 at 8:19

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question appears to be about engineering, which is the application of scientific knowledge to construct a solution to solve a specific problem. As such, it is off topic for this site, which deals with the science, whether theoretical or experimental, of how the natural world works. For more information, see this meta post." – Brandon Enright, David Z
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Hint: Hold out your palm and blow onto it. Then suck from it. Which one creates more flow? – Pranav Hosangadi Apr 27 '14 at 7:25
@PranavHosangadi I could answer you in this way : when I push the air inside Im actually keeping the worm inside while When I suck the air - I'm getting the worm outside faster .......... BUT I could also the opposite. hence my question. – Royi Namir Apr 27 '14 at 7:31
Try it in a box with one end open, see what happens. – Pranav Hosangadi Apr 27 '14 at 7:56
are you serious I cant test it. that's why i ask it. tnx – Royi Namir Apr 27 '14 at 7:58
Are you serious? This has a really simple answer, and I'm asking you to put your hand in any box which has one end open - not that difficult to improvise - and then blow and then suck air and see which one you think makes more sense to use. As for "keeping the warm in / getting the warm out", it's a better idea to have an inlet and outlet for the airflow. – Pranav Hosangadi Apr 27 '14 at 8:00

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