Search found 56 matches

by drownmypc
Sat Mar 07, 2009 6:53 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

I'd say you don't need to guide the air, but your solution for oil flow management seems great! Maybe I'll be able to design the tank to have removable guides, so we'll be able to test that hypothesis. That would be fun. I'm guessing that forced convention will make a significant difference. I pred...
by drownmypc
Sat Mar 07, 2009 5:37 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Re: Evaporative cooling!

Evaporative cooling! A little followup on this evaporative cooling concept -- I had a 3D game paused for a while, came back and noticed that the tank's oil temp had risen to 55C (131F). Even with a couple small (and quiet-ish) fans pointed at the tank. That was a bit hot for my comfort. So, I wrapp...
by drownmypc
Mon Mar 02, 2009 8:44 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Evaporative cooling!

Hmm, this is interesting.

I draped a wet cloth over my oil aquarium and pointed a room fan at it.

With the computer on standby (drawing 4 watts, effectively off) the tank oil temp got down to 65.6F / 18.6C.
That's below the room's ambient temp of 70F / 21.1C.

Evaporative cooling!

Nifty.
by drownmypc
Mon Mar 02, 2009 8:39 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

(edited to add pictures and more detailed description) Another option is to fold it in a zig-zag pattern to increase the surfaces facing both oil and air. Start out with a thin plate (or possibly a couple, adding up to) 50cm high and 400cm wide, to get a 2.0 square metres surface. Then fold it sidew...
by drownmypc
Thu Jan 15, 2009 10:53 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Wow. That blows me away.
by drownmypc
Tue Jan 13, 2009 8:15 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

The overall heat transfer coefficient for a wall or heat exchanger can be calculated as: 1 / U A = 1 / h1 A1 + dxw / k A + 1 / h2 A2 (1) where U = the overall heat transfer coefficient (W/m2K) A = the contact area for each fluid side (m2) k = the thermal conductivity of the material (W/mK) h = the ...
by drownmypc
Sun Jan 11, 2009 8:43 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

The difference between copper and aluminium (about 400 vs about 250) isn't quite as large as the difference between glass and aluminium, so that may explain why the material doesn't matter as much if the choice is between copper and aluminium. It may matter when it's between aluminium and glass. I ...
by drownmypc
Mon Dec 29, 2008 6:23 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

How do you calculate how much heat you lose through a single one of those plates? What does it depend on? The material, thickness, surface area, shape, oil temperature, air temperature? I posted something about thermal transfer in this post: http://www.silentpcreview.com/forums/viewtopic.php?p=3959...
by drownmypc
Mon Dec 29, 2008 6:23 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

[Edit: oops, didn't mean to post this one. How do I delete a post?]
by drownmypc
Mon Dec 29, 2008 9:35 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Even if the material doesn't matter, which I'll believe in an instant, can't you get a bigger surface area / volume ratio by finning the metal plates? It sounds a lot easier to get a finned metal plate than a finned glass plate. Oh, fins! Yes, I certainly agree with you there - glass fins would be ...
by drownmypc
Sun Dec 28, 2008 5:07 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

So isn't it possible to fully passively cool by using a larger aquarium and about 40 liters of mineral oil ? I think so - but maybe a small aquarium with oil will be sufficient. But I haven't even tried that yet, so it is unproven. My original motivation for using a double-hull design was to preven...
by drownmypc
Sun Dec 28, 2008 4:50 pm
Forum: Watercooling
Topic: Wanted: Discussion of Watercooling versus Oil Submersion
Replies: 24
Views: 14646

Re: Lava-lamp PC?

I would definitely go for submerged if I could make my aquarium-pc into a lava-lamp pc (have blobs moving around the aquarium). That's a pretty cool idea! The colored blobs in lava lamps are some kind of waxy/oily substance that won't mix with the water it floats in. The wax and the water parts are...
by drownmypc
Mon Dec 22, 2008 5:42 pm
Forum: Cases and Damping
Topic: Modding & Cutting with Tin Snips
Replies: 93
Views: 157345

wiss rocks

I have a pair of wiss snips. risspy is right: they are excellent.

But, Crisspy claims the straight (yellow) snips are useless. I disagree! I use them for opening the tough plastic packaging that so many computer supplies (cables, etc) often come in. :-)
by drownmypc
Mon Dec 22, 2008 9:52 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Re: some answers

The water evap rate is limited by the solubility of the water in the oil: its near 0. The mineral oil has a very very low evaporation rate at room temperature, I doubt its measurable outside a lab. Vinegar will not prevent algae, and it will smell nasty. I recommend a few changes to your setup: 1)r...
by drownmypc
Sun Dec 21, 2008 7:27 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

evaporative water loss

[Edit: continually updating the table with experimental results] Well, last night I started an experiment on evaporative water loss -- because, as I mentioned recently, I'm annoyed that I keep having to add water to my outer tank. I filled two identical glasses with water. Then I added a little bit ...
by drownmypc
Sun Dec 21, 2008 6:26 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

How hot does the water get? Maybe you just need some high temp loving sucker fish. :lol: Heh! I doubt any fish can tolerate these temps. The oil temp stabilizes at about 120F after approximately 12 hours of power-on time. Ambient air temp is about 70F, so that's a 50F temp delta. I think this temp ...
by drownmypc
Fri Dec 19, 2008 1:47 pm
Forum: Watercooling
Topic: Wanted: Discussion of Watercooling versus Oil Submersion
Replies: 24
Views: 14646

Just checking back in on this thread. Top marks for doing this "for real", drownmypc, and for the excellent detailed analysis of the results. Thanks, Bruce. It has been a lot of fun. I added an update to my other thread about problems (algae, mineral scale, evaporation) I had in my water tank. (I h...
by drownmypc
Fri Dec 19, 2008 1:41 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

medical grade?

which gives me a list of suppliers for the UK, however whenever they ring them they ask what grade mineral oil i want! I dont have a clue, any help? Hi, blundell. I'm guessing they wanted to know whether you needed "food grade", "medical grade", or "industrial grade", etc. I don't know precisely wh...
by drownmypc
Fri Dec 19, 2008 1:24 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

9 months and counting

I drowned my PC in mineral oil 9 months ago. It has worked fine, although it hasn't seen heavy usage. The oil temp gets up to about 120F after about 12 hours of ontime, where it stabilizes (my basement is typically at 65F-70F). The oil tank (inner tank) was always pretty clean looking, except for th...
by drownmypc
Mon Jul 28, 2008 6:55 am
Forum: Watercooling
Topic: Wanted: Discussion of Watercooling versus Oil Submersion
Replies: 24
Views: 14646

You'll need to include "oil vapor" as one of the downsides, if you're thinking about an un-sealed system. It smells terrible, and potentially has health impacts. I've had an unsealed system running for almost 6 months. No smell, no perceptible drop in oil level, air quality (my basement) seems fine...
by drownmypc
Tue Jul 22, 2008 3:28 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

oil-cooled system update: 5 months

My double-hulled oil system has been submerged since early February - about 5 months now. I use it intermittently for games and photoediting. It is off most of the time, but each week it averages maybe 5 powerons and about 5 hours of on time. It still works fine - no loss of performance, no function...
by drownmypc
Tue Jul 22, 2008 3:13 pm
Forum: Watercooling
Topic: Wanted: Discussion of Watercooling versus Oil Submersion
Replies: 24
Views: 14646

If the PC has a power output of 400 W (which is pretty high end), and the walls are a total of 0.6 m2, a 4 mm copper wall means a delta T of 0.06 °C. Aluminium will mean a delta T of 0.11 °C. The difference is practically immeasurable. WOW. Nice work, spookmineer. I was aware of the thermal condu...
by drownmypc
Thu May 15, 2008 10:28 pm
Forum: Watercooling
Topic: Wanted: Discussion of Watercooling versus Oil Submersion
Replies: 24
Views: 14646

you'd probably need a much higher flowrate to make up for poor heat capacity of min. oil (60% less than water). I agree. The upside of replacing the water in a conventional pump/tubing/waterblock/radiator setup is that spills won't fry your computer. But the downside is that you lose a lot of cooli...
by drownmypc
Tue May 06, 2008 6:47 pm
Forum: Watercooling
Topic: Wanted: Discussion of Watercooling versus Oil Submersion
Replies: 24
Views: 14646

Wanted: Discussion of Watercooling versus Oil Submersion

I'm interested in discussing the relative merits of conventional watercooling (water blocks, tubing, pumps) versus oil-submersion (aquarium, mineral oil). No religion, please! I am not personally advocating either approach (although I have more experience with oil submersion than water cooling). I w...
by drownmypc
Thu May 01, 2008 8:58 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

I would still would love to see what would happen to the temps if you slid in a piece of metal, about the same size as the plexi the mobo's on, into the tank. maybe heavy gauge corrugated roofing? Okay, I tried it. I had a sheet of steel, about 1/16" thick, maybe 16x24. I stuck it into the tank lon...
by drownmypc
Sat Apr 26, 2008 8:08 am
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

I would still would love to see what would happen to the temps if you slid in a piece of metal, about the same size as the plexi the mobo's on, into the tank. maybe heavy gauge corrugated roofing? I would think it would really help a lot ...especially if the psu exhaust fan was aimed at the exposed...
by drownmypc
Wed Mar 26, 2008 8:37 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Hi, wim. Yeah, I have a reserator2 sitting next to me (I tinkered with water cooling a while back). Lessee here...it's about 12 inches long, 11 inches tall = 1.83 sq ft without the fins. But there are 50 fins, each 11 inches long and 1 inch wide (at about 1/2 inch spacing). That's another 3.82 sq ft...
by drownmypc
Wed Mar 26, 2008 8:27 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Hi, Bruce! I was happy to see that your results are pretty close to what you predicted with the spreadsheet. I was pretty surprised by that, really. I mean, so much of it is estimation and guesswork. I didn't think they'd be even close. I got the mineral oil from an agricultural supply store here ca...
by drownmypc
Wed Mar 26, 2008 8:05 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

Hmm, following up on previous post: so theory seems to be in the right ballpark, and my spreadsheet might be almost accurate. Now, suppose my mobo+GPU were pulling 500W. My spreadsheet predicts the water temp would have to be at 80C (=176F) in order to shed 500W of heat energy from a 20x10x12 tank G...
by drownmypc
Wed Mar 26, 2008 7:17 pm
Forum: Watercooling
Topic: PC in aquarium full of mineral oil
Replies: 136
Views: 158444

sanity check on heat loss calculations

Earlier in this thread I gave tables on how quickly a hot aquarium would shed heat. Was theory in the right ballpark? Now that the system is plugged into a power meter, I can do a rough check. The power meter measures 115W at idle. The PSU is rated at 80+% efficiency. So that makes 92+W being delive...