Re: Heatsinking a 3W Luxeon

Jason S wrote:


"GregS" <szekeres@xxxxxxxx> wrote in message
news:e8b3vh$pmc$2@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
In article <44a8970d_1@xxxxxxxxxxxxxxxxxxx>, "Jason S"
<jst3712@xxxxxxxxxxxxxx> wrote:

"Stanislaw Flatto" <compaid@xxxxxxxxxxxxxxxxx> wrote in message
news:QtNpg.1598$Nv4.242519@xxxxxxxxxxxxxxxxxxxx
Jason S wrote:

So what you're saying is the thicker the better?

God forbid, never mentioned anything like this, we are on a group that
has
_design_ in its name, so I treat it as such. For every solution there
is
some calculated result and you can use this as a minimum or add as much
safety factor as you wish, but know what you are doing.

Example: look at any manufactured heat sink, be it on your CPU or the
one
surrounding the piston on your "Harley Davidson". You will notice that
a
lot of material is removed to create larger surface for more efficient
transfer of heat to air.

But the air has to flow freely, no magic about it.

That shouldn't be too much of a problem. You see, I got nowhere to
put
a
fan, that's the reason why I'm posting this!

No need of forced air movement, enough surface of the heat sink in air
and
the warmer air will move up by itself to be replaced by the cooler air
from the surroundings.

Thanks
Jason.


Have fun

Stanislaw
Slack user from Ulladulla.



OK. I had a deep thought about it all, and came up with a major design
change that *can* include a fan... I previously thought it was impossible
(too hard to explain).
Anyway I got this old "486" CPU fan and heatsink combo (about 400 x
400mm)
that I could attach directly onto the luxeon. Remember my casing is well
ventilated to allow single direction air movement. Would this do it??
I'm
thinking that if this heatsink and fan actually cooled down an old 486
"CPU", why couldn't it cool down a 3W luxeon?
Even better, could I use one of those heatsinks designed specifically for
a
LUXEON (stick-on pin grid) and use my CPU fan on that?

You just have to watch the maximum ratings.If the rating was for a 25
deg.
C sink, then you
can never achieve this without peltier added.

greg


Hi Greg,
So you couldn't tell me, off hand, if my old CPU heatsink and fan might do
the trick? This is where I'm struggling...
I got no idea what my old 50x50mm 486 CPU heatsink's thermal resistance is
:-( It's just a spare part I had lying around with no info, with a small
fan attached.

Peltier? If it comes to that, I'll ditch the luxeon idea altogether...
too
much trouble; and power.

Jason.

Do not trust what Greg says without plenty of salt. The old 486 heatsinks
were designed to dissipate 35 to 50 W or more; i suspect that a 3 W luxeon
would not cause temperature rise more than 2 C above ambient.

--
JosephKK
Gegen dummheit kampfen die Gotter Selbst, vergebens.  
--Schiller
.

Relevant Pages

  • Re: Odd crash problem
    ... surrounding the CPU socket ... The CPU fan is then reversed so that it sucks up ... This case is of the squatter fatter design ... magnificant asset when I realised that a replacement PSU ...
    (uk.comp.homebuilt)
  • Re: Is 67deg C hot for an AMD Athlon XP 3200 2.19GHz processor
    ... back to the CPU - is this is a bit on the warm side? ... I think the random shutdowns were definitely due to the dodgy case fan. ... Going to what I said elsewhere in the thread there is actually a holder for a fan at the front of the case to draw air in, and also one at the side of the case. ...
    (uk.comp.homebuilt)
  • Re: Is 67deg C hot for an AMD Athlon XP 3200 2.19GHz processor
    ... back to the CPU - is this is a bit on the warm side? ... I think the random shutdowns were definitely due to the dodgy case fan. ... Going to what I said elsewhere in the thread there is actually a holder for a fan at the front of the case to draw air in, and also one at the side of the case. ...
    (uk.comp.homebuilt)
  • Re: DS10L surgery report
    ... The fan intakes are just small ... but also enlarges the available ara for the fan to suck air. ... CPU air outlet and the PCI riser card. ... front area between the PCI riser card and the CPU housing. ...
    (comp.os.vms)
  • Re: Heatsinking a 3W Luxeon
    ... But the air has to flow freely, ... I had a deep thought about it all, and came up with a major design ... change that *can* include a fan... ... Anyway I got this old "486" CPU fan and heatsink combo (about 400 x ...
    (sci.electronics.design)
Quantcast