cfl's

[kreed]

On May 16, 10:19 pm, Mickel <mic...@nospam.com> wrote:

On 15/05/11 8:23 PM, Trevor Wilson wrote:

**Possible, but dumb. Use a 36 Volt supply.

How do I do that in the car?

**As others have said, you'll need VERY good bonding and a fan. Look for a
heat sink with better than 1.5 degrees C/Watt (at a minimum!). 1 degree
C/Watt would be better. LEDs lose efficiency as temperatures rise.

It could be interesting. 50W of power is similar to a computer CPU and
those don't run very long without a fan

A low powered desktop CPU Some of them quote 90-140w, and in the
case of an IC, AFAIK, almost all of that
is lost in heat.

Kind of like getting 1-2 50w soldering irons, (though the top of a CPU
probably has a much smaller surface area than a soldering iron tip and
shaft) and getting them to stay below about 50 c when running
continuously. Think of the heatsink area it would need without a fan.

 

[Jeßus]

On Mon, 16 May 2011 17:12:11 +1000, "Trevor Wilson"
<trevor@rageaudio.com.au> wrote:

Jeßus wrote:
On Sun, 15 May 2011 11:45:14 +1000, "Trevor Wilson"
trevor@rageaudio.com.au> wrote:


**I was hoping that the gummint would ban open fires. Dr Karl has
stated that the pollution caused by a very high end, very high
efficiency fireplace (expensive) in one hour is more than a typical
car causes over one year (pollution, not CO2). The particulates from
fireplaces is disgusting. There are several morons in my area who
insist on buring wood for wamth.

You are - and apparently always will be - absolutely clueless on these
matters. Always default to simplistic PC environmental opinions, for
some reason.

**I specified my source for the information. I can certainly attest to the
disgusting smoke on a still night in my area, where there are a tiny handful
of fires burning. I'm lucky. The smoke doesn't bother me, but I pity those
who have breathing difficulties.


I wonder where 'Dr Karl' got his info from, or whether he bothered to
verify it for himself? It's sounds highly exaggerated to me. How much
particulate escapes depends on so many factors...

**Indeed, which is why he specified a high end, modern fireplace.

Type of wood, how green is it (if at all), how much moisture it
contains, the weather itself and of course the fireplace/wood
heater/stove characteristics would all make a difference.

Using wood for fuel releases the same amount of carbon had that same
piece of wood been left on the ground to rot... albeit it releases all
that carbon in a very short time when burnt.

**You may care to read what I wrote. I carefully excluded the CO2 effects,
for precisely that reason. Decomposition, however, does not release
combustion products that can be harmful to those who have breathing
problems.

Indeed.

I'll happily keep running my wood heater(s) and combustion stove until
I keel over and cark it. It's none of yours or anyone else's damned
business.

**Nice attitude. Fuck everyone around you, as long as you're OK. Is that
about it?

Not really. My nearest neighbor is about 2KM away, who also uses wood
for heating and cooking... which brings us around to another thing I
take issue with - your generalising about banning fires. The notion of
_not_ using wood heaters here (NE Tasmania) is simply absurd Most
urban areas are another matter... but then theres no end to the
problems living in such places. I'm just glad they all do in fact live
there and not in the bush...

 

[Jeßus]

On Mon, 16 May 2011 23:19:04 +1000, terryc
<newsninespam-spam@woa.com.au> wrote:

Trevor Wilson wrote:

I wonder where 'Dr Karl' got his info from, or whether he bothered to
verify it for himself? It's sounds highly exaggerated to me. How much
particulate escapes depends on so many factors...

**Indeed, which is why he specified a high end, modern fireplace.

Fireplace? I don't know of any one who burns wood that has a fireplace.

They still get used, but yeah, a normal wood heater is vastly more
efficient than an open fireplace.

 

[Mickel]

On 16/05/11 11:19 PM, kreed wrote:

A low powered desktop CPU Some of them quote 90-140w, and in the
case of an IC, AFAIK, almost all of that
is lost in heat.

Every last ounce of power than goes into a cpu gets lost in heat. I had
this conversation recently with someone about how much heat from a 60W
light bulb ends up heating the room. My answer was all of it assuming no
light escapes out the windows.

Kind of like getting 1-2 50w soldering irons, (though the top of a CPU
probably has a much smaller surface area than a soldering iron tip and
shaft) and getting them to stay below about 50 c when running
continuously. Think of the heatsink area it would need without a fan.

It will be interesting the see. If it is a problem then I will just get
a bigger heatsink or run the fan.

 

[kreed]

On May 18, 9:36 pm, Mickel <mic...@nospam.com> wrote:

On 16/05/11 11:19 PM, kreed wrote:

A low powered desktop CPU   Some of them quote 90-140w, and in the
case of an IC, AFAIK, almost all of that
is lost in heat.

Every last ounce of power than goes into a cpu gets lost in heat. I had
this conversation recently with someone about how much heat from a 60W
light bulb ends up heating the room. My answer was all of it assuming no
light escapes out the windows.

That would be correct. The computer analogy would also be correct
when I think about it, assuming
no light from the monitor leaves the room via windows also.
Everything that goes into the PC and its parts would turn into heat.

Kind of like getting 1-2 50w soldering irons, (though the top of a CPU
probably has a much smaller surface area than a soldering iron tip and
shaft) and getting them to stay below about 50 c when running
continuously.  Think of the heatsink area it would need without a fan..

It will be interesting the see. If it is a problem then I will just get
a bigger heatsink or run the fan.

Excellent thermal bonding is essential between the LED package and the
heatsink, to allow the heat to flow through from the LED's to the
heatsink fast enough. An analogy would be like putting a 1/2" pipe in
to drain your shower. The sewer system can easily handle the amount
of water that needs to be drained, but the small drain pipe to the
sewer becomes a bottleneck.
The water would build up, faster than it could leave. The same
happens with the heat in this LED/Heatsink design if there isnt a VERY
good thermal bond.

 

[Mickel]

On 19/05/11 1:16 AM, kreed wrote:

That would be correct. The computer analogy would also be correct
when I think about it, assuming
no light from the monitor leaves the room via windows also.
Everything that goes into the PC and its parts would turn into heat.

It must be correct because, being a newsgroup, 50 people would have
jumped in to tell us what idiots we are otherwise

Excellent thermal bonding is essential between the LED package and the
heatsink, to allow the heat to flow through from the LED's to the
heatsink fast enough. An analogy would be like putting a 1/2" pipe in
to drain your shower. The sewer system can easily handle the amount
of water that needs to be drained, but the small drain pipe to the
sewer becomes a bottleneck.
The water would build up, faster than it could leave. The same
happens with the heat in this LED/Heatsink design if there isnt a VERY
good thermal bond.

Do you think CPU paste will be ok?
>

 

[kreed]

On May 19, 7:19 pm, Mickel <mic...@nospam.com> wrote:

On 19/05/11 1:16 AM, kreed wrote:

That would be correct.  The computer analogy would also be correct
when I think about it, assuming
no light from the monitor leaves the room via windows also.
Everything that goes into the PC and its parts would turn into heat.

It must be correct because, being a newsgroup, 50 people would have
jumped in to tell us what idiots we are otherwise

Excellent thermal bonding is essential between the LED package and the
heatsink, to allow the heat to flow through from the LED's to the
heatsink fast enough.  An analogy would be like putting a 1/2" pipe in
to drain your shower.  The sewer system can easily handle the amount
of water that needs to be drained, but the small drain pipe to the
sewer becomes a bottleneck.
The water would build up, faster than it could leave.  The same
happens with the heat in this LED/Heatsink design if there isnt a VERY
good thermal bond.

Do you think CPU paste will be ok?

You will need that, but you need a good area of surface to surface
contact.