Cooling Non-Submersion Mineral Oil Coolant

ive never read the article, but all fluorinert evaporates quite readily, so sounds plausible.

ive tried undervolting my pump to slow the water flow down to the volume of the mineral oil, but this pump seems to seriously dislike low voltage and i cant get it to run at anything much below full speed. ive tried pinching the tubing off to slow the flow, but i dont have a decent set of pliers here at the house, all my tools are at work.

 

What we really need is someone with a liquid metal pump and a couple litres of mercury to see what that does in a closed loop.

 

send me all your old thermostats, ill find out

 

I've been doing a lot of reading about fluorinert for the last few hours, and have read a few places (one of them is http://forum.corsair.com/v3/showthread.php?t=25976) that it will will eat through plastics over time, meaning PVC tubing can't be used and some reservoirs would eventually disintegrate. If that's true, what do you use to get round that?

 

What about silicon tubing metal pipes(just read it goes through tygon, PVC and silicon tubes) and a metal with glass top reservoir?

 

Yeah, I guess I'll have to read up on how to connect copper tubing to blocks etc. Can't just squeeze it onto a barb And I'm not sure what pumps and tops are safe either, as I would like it to last a few years when I do it, but I've got a few months to properly plan the loop I would be using it in.. Doesn't sound like I'll want to use it for too many short benchmarking runs though, and a multi-PC loop just sounds too complicated

 

hard coolant lines and fuel cell as a res and a seriously solid pump

 

compression fittings work fine with copper lines. you could also use solder-on swivel headed fittings.

 

well i finally got around to bringing home my pinch-off pliers to cut the flow down on the water setup. i was able to squeeze the flow down to just barely a trickle. obviously i have no way to quantify the flow volume with mineral oil, so this isnt extremely scientific. but i just wanted to get an idea of how much flow would effect cooling.

but its bad news again for the mineral oil. while i was able to bring the cpu temp up 6 degrees to a max of 51c by slowing the water flow, the water still bested the mineral oil by a whopping 14 degrees.

on a side note, it takes an AMAZINGLY small amount of water to keep a CPU cool. while 51c isnt a ground breaking temp, thats still 18 degrees cooler then the stock air cooler and probably on par with a good aftermarket air cooler on this CPU. and all that with a flow so slow that it didnt come close to filling the 3/8" line running from the block to the rad. there was a trickle of water maybe 3mm in diameter coming into the res.

 

I love stuff like this. Stuff nobody thinks of doing because of so called "common sense." Pfah! Much more fun to defy common sense and see just what you can do. Sure, this didn't turn out so well, but maybe next time will be the diamond farting miracle we've been waiting for!

 

I know this is an old thread, but I'm curious if anyone considered flow rate. I'm curious what your actual flow rate is with mineral oil and if we could calculate what kind of cooling you'd expect at different flow rates.

Also, after looking into mineral oil compatible pumps, I've noticed they all (that I've found) are subject to PSI. For example, a Varna EP-4 DC pump can push 1.8GPM @ 12VDC/5A with a max of 60PSI. I've also noted that almost all oil pumps are "metered", so assuming the viscosity of the fluid isn't too high, it will alway push 1.8GPM. This is really only important when using fluids of different viscosities. Your pump is not metered so it will push as fast as it can. Let's say with water it can do 95GPM, but with oil it can only manage 1.5GPM (not accurate, just speculation).

To go a little further, if you were to match flow rate, what performance would you see at 2GPM of water compared to oil? The difference might not be as drastic... I am looking around for high flow oil pumps and I'm willing to experiment.

My plan is to use 1/2" copper tubing, custom milled block, 120.1 or 120.2 radiator, and a metered pump (2-4GPM). I'll see if I can find a flow meter and temp sensor that is compatible with mineral oil and throw it in the loop somewhere. My loop will be the constant and the fluids will be the variable. Question is, what is a good testing methodology.

 

If you'll skim through the last post i made, youll see that i attempted exactly what youre suggesting. i used pinch-off pliers to slow the water flow down to roughly the same flow rate as the mineral oil in an attempt to eliminate volume from the equation.

the results were that the water still cooled significantly better than the mineral oil did. theres just no getting around the mineral oils lazy thermal transfer properties.

granted, my flow test was not wholly accurate as i had no way to measure flow. but id say i had the flow rate of the water and the flow rate of the mineral reasonably closely matched. if i had to guess id say i was working with between 0.25-0.5 gallons per minute. it was VERY slow.

do keep us posted on what your test result show. it sounds like yours will be a nice platform to test a wide variety of different viscosity liquids.

 

Wicked_Sludge,

By no means am I attempting to debunk your testing method, merely suggesting improvements. My theory is there is probably a median flow rate at which a minimal maintenance loop (such as mineral oil) could provide adequate cooling. Albeit, not high performance. This may really be pointless if you consider the costs that would be involved compared to water or air. Hey, it's all in good fun tho, right?

 

Many years ago I used an industrial engine coolant from Evans. It was clear but thicker than water. Temps were not good. The coolant was designed as a water substitute to cool radiator engines.

People shouldn't be using water these days. EC6 is made from vegetables and has cooling properties slightly better than water.

 

how long does that stuff last in a loop before it begins to decay and must be replaced?

 

17 mins and 25 seconds.

 

Exactly this. Half the fun of building a computer is actually using it. The other half is screwing around with it, replacing parts with better ones, and just tinkering around with it.

 

Perhaps suspending nano metallic particles in the coolant to increase heat removal capacity.

 

since feathers is more interested in behaving like a school boy than participating in the active discussion:

for those who are curious, it looks like most everyone is suggesting a 2 year shelf life for the ec6. id imagine with the heat from a functioning loop itd be somewhat less. but even if you have to flush the loop every year thats still not bad since its relatively cheap. still, i wonder exactly what they mean by "85% Bio-degradable Within 30 Days".

 

It means the bio-degredation of the oil if you pour it into your garden. Has something to do with biochemical reactions and bacteria etc.

In a sealed loop like a water-cooling-loop there usually isn't alot of biochemical reactions happening because of the lack of bacteria and oxygen, so your estimated 12 month wihtout needing to do maintenance should be quiet ok.

Factory-sealed loops usually don't have any bacteria or oxygen at all to cope with so they last for years without maintenance. Thats why you get some 5 years warranty for products like the Corsair H60/100.