cooling fan

[lerameur]

Hello,

I have a module which requires a heatsink. I want to add a fan about 3
inches away. My dilmena is this. Should I be blowing air on the heat
sink, or should I be blowing air out of the enclosed module. I made
hole all around so there is a breathing space.

ken

 

[Jamie]

Hello,

I have a module which requires a heatsink. I want to add a fan about 3
inches away. My dilmena is this. Should I be blowing air on the heat
sink, or should I be blowing air out of the enclosed module. I made
hole all around so there is a breathing space.

ken

have a vent that cool air can be brought into, pull air out
across the sinks. the intake should have a filter.

 

[Rich Grise]

Hello,

I have a module which requires a heatsink. I want to add a fan about 3
inches away. My dilmena is this. Should I be blowing air on the heat
sink, or should I be blowing air out of the enclosed module. I made
hole all around so there is a breathing space.

Depending on what kind of heat transfer you need, if you don't have any
ducting, I'd blow the air from the fan towards the heatsink. If you try
to suck the air away, a lot of it could miss the heatsink, unless, like
I say, you've got some kine of ducting.

A dust filter on the intake side of the fan would do no harm.

Good Luck!
Rich

 

[Puckdropper]

On Tue, 30 Jan 2007 17:42:05 -0800, lerameur wrote: *trim*

*trim*


Depending on what kind of heat transfer you need, if you don't have any
ducting, I'd blow the air from the fan towards the heatsink. If you try
to suck the air away, a lot of it could miss the heatsink, unless, like
I say, you've got some kine of ducting.

I agree, blow the air where you want it to go, don't suck it away.

A dust filter on the intake side of the fan would do no harm.

....until it clogs. Your fan may have to work harder when the filter's
dirty (depending on where it is) which may shorten its useful life.

Good Luck!
Rich

Puckdropper

 

[John Larkin]

Hello,

I have a module which requires a heatsink. I want to add a fan about 3
inches away. My dilmena is this. Should I be blowing air on the heat
sink, or should I be blowing air out of the enclosed module. I made
hole all around so there is a breathing space.

ken

Hard to say, without knowing how much cooling you need. But the best
thing would be to have the fan intake cool air from outside, blast it
directly onto the heatsink fins at close range, and allow the heated
air to escape through vent holes.

The reverse would work almost as well: Have the fan exhaust air from
the box, and place the heatsink very near or in the only intake port.

Either way, you'd be forcing cool air through the heatsink fins. Given
a chance, air prefers to flow *around* the fins, so don't give it a
that option.

As Rich points out, you can blow air some distance directionally, but
you can't suck air directionally.

John

 

[Eeyore]

Hello,

I have a module which requires a heatsink. I want to add a fan about 3
inches away. My dilmena is this. Should I be blowing air on the heat
sink, or should I be blowing air out of the enclosed module.

It all depends on the route the air takes ( backpressure ).

Sometimes it's better to blow, sometimes to suck.

Graham

 

[lerameur]

Ok so I gues i will be blowing.
I dont have a filter, just a metallic grid on the cover.

ken

 

[Rich Grise]

Ok so I gues i will be blowing.
I dont have a filter, just a metallic grid on the cover.

Puckdropper mentioned that a filter will have to be changed,
but I guess I'd rather periodically change filters than fix
the equipment when the heatsink itself loads up with dust.

I had that happen to a computer the CPU heatsink was totally
clogged with dust, and the fan was stuck. The 'puter was
erratic. I replaced the fan, blew out the heatsink, and it
works fine now.

Then again, I run my computers with the side panel completely
off, bypassing any filtering.

Cheers!
Rich