Double looped Bong?
 

I've been thinking of making a bong system something like this:
http://members.sigecom.net/unloaded/dblbong.jpg
The two main things I dislike about bongs are 1) water exposed to air going through my system. 2) if water dries up=fried cpu. So I thought a setup like this would adress both problems. I'm wondering if the air/water on the rad would benefit cooling much. Has anybody tried this? Or have any opinions? I did a bit of searching but haven't seen anything setup like this.

peace.
unloaded

I posted this on OC board but didn't get much response, what do you guys think?

Thats an interesting design. My first setup utilized a bong instead of a heatercore, and I've actually thought about switching back to the bong (destroyed my heatercore and bongs cool better than heatercores do from my experience). The thing I like about your setup is that the cooling water isn't actually exposed to the surroundings, so dust and other crap wont get into the loop, and as far as the water cooling the rad goes, we all know that water is a better medium for transporting heat than air, so i would think that would work better than the typical bong design.

I really don't understand the fuss about the water level. Just tap into the house's piping, and run a small 1/4 line to a float valve. Common parts at any hardware store.

As for your setup, it's a dual loop (duh!). I assume that you would set the radiator at the lowest point possible, while allowing the air to vent through it. The question is: is it worth it?

The water would fall through the rad, and assuming that it doesn't restrict the airflow, it would drip down to the bottom (hot) where it would be pumped back up, to the shower head, then drip down (and cool) itself from the airflow.

But some of the airflow will include heat from the rad.

All in all, I believe that it would not be much of an improvement over a straight rad-and-fan combo, or a straight bong. If anything, you might try seperating the rad, and letting the flow go through the bong (an arrangement in series).

Since the bong requires a lot of pressure, it would have to have its own pump, but you were ready for that (right?).

I have been thinking of spliting the tank, with the pump 0n one side and the shower head dripping on the other side. the float valve would be on the pump side

Actually, if you simply moved the radiator below the cold air intake for the bong, I think you'll be set: The hot air will be more or less limited to live between the rad and the bong's water level, and the bong's air intake will stay cold and simply interact with the bong water. This will also mean you get better airflow, since the air does not need to force it's way through the rad, and the rad will get a better interface with the water b/c the air won't be trying to push it the wrong direction.

And that's fine, but it boils down to a straight bong cooler, except that the coolant is isolated, and that it has to go through another interface (the rad), which all in all, will reduce the efficiency of the cooling system.

On the other hand, it'd have to be quite a large bong, if one is going to fit a heatercore in it, so maybe it's not so bad after all!

The heatercore could act as a nice sound damper for the waterfall.

Other than that, there's still the issue with all bongs: what do you do with the escaping humid air?

I have a similar idea, with the variation that I don’t like to wet the radiator, as water between fins would obstruct airflow. My idea is to put the rad on the air exhaust of the bong, as this air is cooler than ambient, and you’re not heating bong’s water.

How do you figure that?

wouldn't the radiator get corroded pretty quick?

You're better off snaking a soft copper tubing coil in the water at the bottom. That'll do better than the heatercore, IMHO. It would be cheaper, too.

The heatercore would corrode like a mofo if left exposed to water and air. By submerging the copper completely in water that never hits anything but plastic or neutral metal parts, the copper tubing should barely corrode, IF IT IS NOT EXPOSED TO AIR.

As for the humidity problem, get a nice pump for your computer and put the bong outside your house. It doesn't matter if junk gets into it, since it should be easy to hose out every now and then (or set up a chimney cover on top of it to prevent leaves and shit from getting in).

If I ever decide to use a bong, that is how I'd do it, just for reliability's sake.

nicozeg: air on the exhaust of the bong is warm and damp. It's the water you're cooling with air...The water gets colder, and air warmer...

Wow, lottsa comments 8) A few comments. I was planning on needing two pumps so thats not an issue. Also having the core mounted above the fan is a major part of the plan. If the bong half is off or dry, the closed wb loop will still work as the bong acts like a big shroud. Also the core acts as the extra medium other people use in their bongs to increase surface area for the water. I've seen anything from ping pong balls to scotch brite pads used, all to cause more evaporation. I figure with the added surface of the core plus the bit of heat there, thats where most of the evaporating will take place. As I understand it, that where the real cooling takes place, a the water evaporates, not as the drops hit cool moving air. Humidity shouldn't be a real problem for now, as its winter here and gas furnace really dries the air out. It's about time to setup my humidifier anyway. My biggest concern would be buildup on the core. I was thinking of using distilled water and the additives that would go in my humidifier--bactrostat and buildup preventer. Well this started as just a theory, but I think I'm really gonna haveta try it now. I've got tons of plexi, a new table saw, lottsa clamps and glues, so I might as well. The toughest part looks to be getting a good seal around the core and it still being removeable.

peace.
unloaded

Well, the main cooling factor in a bong is the evaporation, where energy (heat) is absorbed by this phase change operation. If it were only convection, heat will be transferred from on medium to the other, but in this case is a mix of both.

Also, this bong loop don’t have a heat source; only the pump, that don’t need to be a powerful one. So the bong would be acting like a swamp cooler, blowing cool air.

Sorry Nico, but you're making less sense than ever!

Heat comes into the bong assembly from the rad, and exits as hot air.

hehe, i think he's talking about the bong water not directly going to a wb.

so you guys think this setup would get ambient or lower temps? or do you think it wouldn't have results worth the effort?

if you want result dunk the rad in the water:D

what are you afraid of,the rad will not melt and you will have less problem with calcium deposit on the fin :D

I think that the whole bong thing is dying because the heatloads today are too high.

You should try to gather data on other bongs (and filter out the garbage from those people that measured temps after letting it run for 1 minute). Get the heatload, and CPU temps.

Start surfing!

Why dont you build a twister and then put the radiator just below it. That way you have high velocity water forced throught the raditator and you still have something cool to look at. :D :D :D :D

I think you don’t get my idea :confused:

Let’s try to agree in something:

Imagine a bong running without a computer, with water running and air blowing. What do you think would happen?
a) Nothing, water and air stay at ambient temp
b) Water and air become colder
c) Water and air start to heat up
d) None of the above, the dog drinks the water and the pump fuses.

I say it’s b)

Now let’s see a common heatercore setup. Water temp usually stabilizes some degrees over ambient air, depending of the system performance.

And what happens if you mix both situations, and feed the rad with cooler than ambient air from the bong?

I think that’s a way of improving overall system performance, and I don’t care if air at the end is hot; I like heat being there and not on my cpu!

I'm thinking it would get better cooling with the evaporation happening on the core and the airflowing thru it. It might work ok submerged, but then I'd haveta rig some way to get the water flowing thru the rad where the air usually flows. This would make the complexity and the size go up considerably.

peace.
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I say it's e) none of the above.

if the water gets colder (as it should, unless the pump add a lot of heat), then the heat has to go somewhere. Do we agree there?

Where do you think the heat goes?;)

But if you say that water is colder, and there are no more heat sources, that cold water should cool the air al least, how is going to be hot? The fan motor?

nico, dont forget the fan is introducing warm ambiant air,your rad bring in even warmer air you loose that residual cooler air coming of the surface of the water :D

Heat loads have nothing to do with it, a good bong will always out-perform even the best/biggest radiator, since a rad can only ever just approach ambient, and a bong can get X below ambient (depending on humidity ect)

This exprimental bong;
http://users.bigpond.net.au/volenti/...tup_closer.jpg

is running around 2-3 degrees below ambient while cooling a p41.8@2.6 1.8v, northbridge, radeon 9700pro core at 390mhz, and with a 70w pump in the res.

I'd say it's the high matainance of bongs that put many people off.

Hot Damn!

I wouldn't assume that because sub-ambient is a possibility, that a bong can do better than a heatercore, but yours is fairly large, so I'm sure that it can take the heat.

Ok, so if you add a float valve for a refill, what kind of maintenance is required?

Man, I wish I had the time to try this out!

BB2K
You have the problem that if you use tap water, every salt (calcium, sodium) will start to deposit or clog the block. You will also have a higher elecrtical conducitivity.
Using disitilled water would solve the problem, but then, you need another thank (bigger) that would be connected to the float.
Same system as using the 1/4 hose you told, but instead of using the pipe system of the house but instead using a bigger (and at a higher height) tank so you don't have too much water at the bottom of the bong( which will hinder the perfomance of the bong to go below ambient but will also act as a buffer).

I think Xjinn, when he develloped is bong, calculated that it could cool around 700 watt of heat.

In a double loop bong setup, the calcium deposits and such will not be an issue if the radiator is submerged. You'd just have to CLR your showerhead every once in a while. Hooking up to a float valve would be a briliant way of doing this.

Having evaporation happen on your core, though, is a big ass no-no. Think of the buildup of minerals you'd suffer. Seriously consider a coiled 1/2" copper tube submerged. Since there are no elbows, it would have much less resistance, and in the end you'll have plenty of surface area. Also, it would be submerged in the coolest part of the system: the place where all the freshly cooled water is chillin'. One other problem with having the core suspended above the fan is that the core would lower airflow, requiring a more powerful and louder fan to get the desired CFM through the unit.

Seriously, suspending a core is bad news, requiring distilled water or failure will come soon. Submerging a core will hamper water flow around and through it. Submerging a coil, on the other hand, there is no real resistance in any flow direction. There was a guy on OC forums, I think, that was setting up something similar to what I am describing. Check that out.

Ben: I don’t know the precise physics explanation, but an evaporative cooling system just take out the heat because that’s the energy needed to turn water into vapor. That energy is stored in the vapor and is released when it condensates and return to liquid state. It’s just the same as in a phase change cooling loop, where cold is generated at the evaporator, and heat is released at the condenser. Only difference is that here you forget about the condensation part, and dispose off the coolant in its vapor state; and refill it with liquid one. You just give Mother Nature the job of the condensation stage. :)

Volenti: How much water evaporates daily that setup? I bet that several liters a day
And how did you solder the vertical pipes? I don’t see the tees.
Very efficient design! You don’t waste pump power with a big height.

OT: Ben, when I first read the forum in the morning, the radius thread was dead on the 10K reads mark.

to volenti can you explain your setup, it look like a heat exchanger that should seat inside your reservoir, but, it is insulated and the fans are siting on top maybe a picture of the complete bong will help
:D