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Recently on an aquarium related forum, I called out someone for making what I considered to be an outlandish claim and I was supported by several others. However I wish to get the opinion and/or facts explained by someone from a purely scientific standpoint.
This has to do with the heat dissipation properties of aluminum used to as an LED heat sink.
The DIY LED fixture in question is simply a piece of aluminum sheet, roughly 4" x 6" and probably a few millimeters thick, with four 3-watt LEDs in a diamond/square pattern. The fixture would be oriented with LEDs down.
So this guys posts "top side should be painted flat or satin black to reduce heat" which I thought was nonsensical.
Someone else caught it and posted "How does painting a heatsink make it work better?"
The response was "It the Black Body Radiator effect." [sic]
My response was literally "Are you serious?"
...and yes, he was.
Now, I'm a EE, PE, in the consulting industry, and I do deal with lighting so I understand at a rather admittedly rudimentary level what a Black Body Radiator is, and my initial reaction was that this guy was crazy to think that painting something black would make it have a greater heat dissipation rate, let alone call it a BBR or related that 'effect' back to it in any way.
A comment was made that even a thin coat of paint would act more as an insulator, but the guy still claimed that painting it black made it a BBR and it was cooler to the touch.
So, the bottom line here is that I would like someone to verify this, right or wrong, as I am mildly satisfied that I am right, but sure would like some scientific backing to go with it.
To get the whole picture, go to the following thread
http://www.reefcentral.com/forums/showthread.php?t=1977420
Then start at post # 5030 and read through to post #5064, where the conversation on that particular topic is pretty much over.
Posts by me are "Floyd R Turbo" and pay particular attention to the posts made by "BeanAnimal" on posts 5046, 5050, and 5058.
"Santa Monica" is the user making the claim...
Thanks in advance!
Bud
This has to do with the heat dissipation properties of aluminum used to as an LED heat sink.
The DIY LED fixture in question is simply a piece of aluminum sheet, roughly 4" x 6" and probably a few millimeters thick, with four 3-watt LEDs in a diamond/square pattern. The fixture would be oriented with LEDs down.
So this guys posts "top side should be painted flat or satin black to reduce heat" which I thought was nonsensical.
Someone else caught it and posted "How does painting a heatsink make it work better?"
The response was "It the Black Body Radiator effect." [sic]
My response was literally "Are you serious?"
...and yes, he was.
Now, I'm a EE, PE, in the consulting industry, and I do deal with lighting so I understand at a rather admittedly rudimentary level what a Black Body Radiator is, and my initial reaction was that this guy was crazy to think that painting something black would make it have a greater heat dissipation rate, let alone call it a BBR or related that 'effect' back to it in any way.
A comment was made that even a thin coat of paint would act more as an insulator, but the guy still claimed that painting it black made it a BBR and it was cooler to the touch.
So, the bottom line here is that I would like someone to verify this, right or wrong, as I am mildly satisfied that I am right, but sure would like some scientific backing to go with it.
To get the whole picture, go to the following thread
http://www.reefcentral.com/forums/showthread.php?t=1977420
Then start at post # 5030 and read through to post #5064, where the conversation on that particular topic is pretty much over.
Posts by me are "Floyd R Turbo" and pay particular attention to the posts made by "BeanAnimal" on posts 5046, 5050, and 5058.
"Santa Monica" is the user making the claim...
Thanks in advance!
Bud