Personal computing discussed
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Mr Bill wrote:Looks like these guys managed to build a 1KW TEC with relatively cheap thermocouples... https://pangea.stanford.edu/ERE/db/WGC/papers/WGC/2015/26009.pdf
ludi wrote:Mr Bill wrote:Looks like these guys managed to build a 1KW TEC with relatively cheap thermocouples... https://pangea.stanford.edu/ERE/db/WGC/papers/WGC/2015/26009.pdf
Chunky device and required a hefty cooling block maintaining about an 80C differential, though.
just brew it! wrote:ludi wrote:Mr Bill wrote:Looks like these guys managed to build a 1KW TEC with relatively cheap thermocouples... https://pangea.stanford.edu/ERE/db/WGC/papers/WGC/2015/26009.pdf
Chunky device and required a hefty cooling block maintaining about an 80C differential, though.
As I noted earlier in the thread, TEGs do require a substantial temperature delta to produce useful amounts of power.
ludi wrote:I've toured several Organic Rankine Cycle (ORC) binary power generation geothermal sites here in the states and in New Zealand. The efficiency of low boiling point organic fluids running turbines with air cooled condensers can get significant power out of temperature differences that would stump any TEG.just brew it! wrote:ludi wrote:Chunky device and required a hefty cooling block maintaining about an 80C differential, though.
As I noted earlier in the thread, TEGs do require a substantial temperature delta to produce useful amounts of power.
Yup...and in this case, the application was low-temp geothermal. The heat source and sink have a great deal of range in which they may operate, compared to the proposed LED application in this thread.
Gilligan wrote:Well guys, you have convinced me. I am still waiting on my Peltier to arrive in the mail, but I guess it's safe to say that its application in the lightsaber is almost definitely a fail. Here is a TEC designed for generation, and it only produces 1.8V and 368mA given a 40 degree temp change (which is what I guess I will be getting with the LED rather quickly). Therefore, the most I will be getting on my water pump is about 0.5 watt, which probably isn't enough to do anything. Right?
On the bright side, I have been putting the saber together using a high power 60mm fan (SVC brand from about 12 years ago! — absurdly loud) placed behind the LED which is mounted to a northbridge heatsink. The saber is a super rough prototype right now, but I did turn it on for some short bursts, and I am pretty much blown away. It's awesome! Ludicrously bright...
I put some clear gift wrap in the tube from the dollar store, and it does wonders for evenly glowing the blade. I also found a 3 inch round mirror at a craft store which fits perfectly at the end of the tube, which also helps with glowing. I am still waiting on my side glow fiber optic cable, and water pump to arrive from China.
For light saber sounds, I bought a 4 dollar lightsaber at walmart (just like this), and took the sound board out. To make it louder, I wired it into a small cell phone speaker which I had laying around. The end result is pretty awesome considering it cost me 4 bucks!
just brew it! wrote:DPete27 wrote:(Related) This article reviews a TEC (peltier) CPU cooler. Interesting to note that efficiency is <15% and that particular cooler needs 20W input to do it's job.
The 20W figure is with the Peltier running at only half power. At full power it uses 40W (and dumps 40W of additional heat into the case). Given the mediocre performance and additional thermal load on the case cooling I really can't see this thing being worth $150; Peltiers for CPU cooling fell out of favor for a reason!
Edit: And the author of the review doesn't seem to understand how thermal resistance works. He keeps saying thermal resistance decreases at higher loads, when it is in fact increasing. Thermal resistance increases, and cooling performance decreases. Or maybe he meant to say thermal efficiency. Or something. Either way, the muddled terminology is annoying.