l0wbob2016
Well-Known Member
i couldnt do a testrun up to now. a friend of me is finishing his grow at the moment and once the room is empty we will fix that light in the room and use it for the next run.
DIY watercooled photosynthetic-research LED-Lamp completed build, tell me what u think
- Thread starter l0wbob2016
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Danielson999
Well-Known Member
That's a very vague question. Any butthead can fill a tent with billions of photons but getting 2lbs per light sounds like it has more to do with genetics and growing skills, not the light.
Abiqua
Well-Known Member
i think i would want copper to take the heat away from really hot water....not use cooler water to wick heat away from copper which it probably does better with al......
l0wbob2016
Well-Known Member
but then this doesnt make sense for me in termes of thermal conductivity. because copper has a higher value than aluminium.
so please explain and if possible give me some science behind so i can understand. thanks
Yeah, youre right on this one. Conductivity is both ways. Aluminum is cheaper and lighter though. And copper doesnt perform better enough to make it worth it.
Also aluminum can hold over twice the heat copper can...
l0wbob2016
Well-Known Member
i totally agree that copper isnt worth the weight and cost for that better cooling performance.
it is more like a choice to drive a ferrari instead of a smart.
Lol. more like a Ferarri vs porshe...
The thing is were using "identical" comparative heatsinks. If copper heatsink conducts heat twice as well as an aluminum one, you can double the surface area of the aluminum heatsink and get similiar results, no? Copper is greater than twice the price of aluminum.... So unless you have size constraints it makes little sense to use all copper. This is why a lot of heatsinks use copper base/ heatpipes to aluminum fins... pretty much the ideal design.
l0wbob2016
Well-Known Member
haha yeah ferrari vs porsche is a better example.
yeah you are right in terms of the surface. another thing i just realized as u mentioned is that i never thought about the size of the aluminium heatsink i would need for my setup. i only got little size constraints above the COB's but maybe aluminium heatsinks would be too big in that specific spot. that small copper heatsink with the pump is pretty small and this gets pumped to a place where the radiator can stand without any place problems.
Abiqua
Well-Known Member
copper absorbs more heat but cannot dissipate it at a fast rate....aluminum may have medium conductivity compared to copper yes but the absorption dissaption ratio is more evenly matched even though conductivity is lower.....the copper will take a while to get hot but might take even longer shedding the heat passively.....and then ruining "sinking". there are positives and negatives both.
l0wbob2016
Well-Known Member
based on what do u have this information? any source for this? i'm just curious...
Danielson999
Well-Known Member
From what I have read, copper actually outperforms aluminum in basically all aspects. Copper conducts/transfers heat almost twice as fast as aluminum and dissipates it faster also. The reason so many people say aluminum dissipates better because of it's lower density is simply because if the heatsink weighs the same (copper vs alu) then the aluminum heatsink will be larger because its density is lower. More surface area, better convection.
The best heatsink for all practical purposes is having copper beside your heat source to transfer the heat away quickest and then having aluminum used to dissipate the heat. The reason being, copper is hard to machine, copper is more expensive and copper is much heavier.
If you had two heatsinks of identical size and shape, copper would be better in every aspect for thermal transfer. The downside is it would be much heavier and cost way more.
One important thing to remember is that heat 'radiation' is a non-factor when we use forced convection for cooling. Even if aluminum is slightly better at 'radiating' heat, the fact we use forced fluid (air or water) means convection is by far the biggest factor (99%) in how well it cools.
Another thing to remember, aluminum does not shed or lose heat better or faster than copper. Not ever.
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Organic Miner
Well-Known Member
Jumping in late here, but isn't the point of using copper in a liquid system to quickly transfer the heat away from source (the COB) through the copper to the liquid and then from the liquid to some other heat transfer mechanism remotely (a fan and radiator )? That's the advantage of using copper over aluminum. Just thinking out loud here.
ttystikk
Well-Known Member
I could pick at your build but I won't. It's well made and looks like it's going to grow the hell out of some weed.
Let's see you out it to work!
ttystikk
Well-Known Member
Do you actively manage the temperature of your fixture with the water? Do you control the water temperature? If so, how?
I ask these questions because my own inquiry into water cooling depended on active temperature management and control of the water flowing through the fixtures.
I've used cold water and hot water thus far. Counterintuitively, changing the temperature made little difference in light output but did cause noticeable changes in the growth characteristics of the plants themselves.
Rider509
Well-Known Member
ttystikk
Well-Known Member
Yep, you read that exactly right.All of my racing radiators are aluminum.
l0wbob2016
Well-Known Member
do whatever you want, i am open for anything thats based on logic so that i can understand
well my AiO-solution came alrdy filled with water ( and some chemicals inside so no bacteria will grow ). taking the temperature i did at the very first days for checking what i get maximum temperature after a couple of hours on max power. i took the temp on 2 places from the outside ( so the temp of the metal on that radiator, not the actual water temp) , one the intake from the pump into the radiator and the other was the outake if the radiator that side that gets the cooled water back to the COB.
the intake had max readings of 41°C and the outtake had a max reading of 39°C after 4 hours at 100% power in a non ventilated room.
if needed i can turn up the power of the watercoolers but for now i dimmed them down as much as the driver let me ( to about 25W for 5 waterpumps plus 5 fans ) and got these results.
i forgot to take temp messurements when the watercoolers work also at 100% power. also i stopped taking the watertemp after i realised there will never be a problem.
if u are using a COB with always the same powersource and completely same way of transfering heat then ofc changing the temp of the water that cools the COB will have an influence on the actuall temp of the COB ( dont use water that cold that after cooling down the COB the water that runs into the radiator is cooler than the room it stands in, this would be trouble )
so what changes in the growth characteristics of the plants did u see? give some examples cause i cant imagine a characteristic changing that hard. thats very interesting.
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l0wbob2016
Well-Known Member
haha made my day
would be funny if these guys werent able to build up a thing like this by themselfes
ttystikk
Well-Known Member
Interesting things happen when you actually try something. Often, you get results you didn't expect.do whatever you want, i am open for anything thats based on logic so that i can understand
well my AiO-solution came alrdy filled with water ( and some chemicals inside so no bacteria will grow ). taking the temperature i did at the very first days for checking what i get maximum temperature after a couple of hours on max power. i took the temp on 2 places from the outside ( so the temp of the metal on that radiator, not the actual water temp) , one the intake from the pump into the radiator and the other was the outake if the radiator that side that gets the cooled water back to the COB.
the intake had max readings of 41°C and the outtake had a max reading of 39°C after 4 hours at 100% power in a non ventilated room.
if needed i can turn up the power of the watercoolers but for now i dimmed them down as much as the driver let me ( to about 25W for 5 waterpumps plus 5 fans ) and got these results.
i forgot to take temp messurements when the watercoolers work also at 100% power. also i stopped taking the watertemp after i realised there will never be a problem.
if u are using a COB with always the same powersource and completely same way of transfering heat then ofc changing the temp of the water that cools the COB will have an influence on the actuall temp of the COB ( dont use water that cold that after cooling down the COB the water that runs into the radiator is cooler than the room it stands in, this would be trouble )
so what changes in the growth characteristics of the plants did u see? give some examples cause i cant imagine a characteristic changing that hard. thats very interesting.
I did run cold water through my modules and I got exactly what I wanted; absolutely no heat in the grow room. Turns out this isn't half as beneficial as it sounds!
Allowing the water to heat up warmed the room, reduced RH and allows the plants to transpire better.