Yes it kinda did. My gues is that you ment to post in this thread but accidently posted in the other one:)I was wondering why the discussion changed from compressor oil to the dangers of nitrous...
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Yes it kinda did. My gues is that you ment to post in this thread but accidently posted in the other one:)I was wondering why the discussion changed from compressor oil to the dangers of nitrous...
Chilly1 when did you hit that INSANE temp???????
I think that is in Kelvin, and 300 is actually quite high
um actualy its in ferenheit. Its impossible to be kelvin b/c it is negative. Well I found the thread. But I think LN2 is cheating...... Still very nice setup over there.
Why is Ln2 cheating It is using a pump and a compressor to cool that much, plus with one more stage I will be able to liquify nitrogen...
And Yes that is -300F and that is -185C
not reusable, i thought that it was in a closed system :( .
btw if you are going to the lowest pobbible temp why dont you pull a nice vacuum on something then let some ln2 in? rolly be realy realy cold and frosty
I am using a vacume pump on the outlet of the block to siphon the nitrogen out of the dewer. (No styrofoam cups)
Just to clean things up.
NOS = Nitrous Oxide System
That's the also the most known manufacturer for such car systems, so everyone calls it NOS. :D
I think a warning is in place here!
If you are working with LN2 temps things are starting to become VERY much harder to insulate. And there are real DANGERS if it is not done properly! These dangers are possibly even more severe than the dangers of cascade systems! WAY more severe!
Ok, this danger is caused by the following:
When not insulating metal parts that are at LN2 temps there is serious chance of condensing Liquid Oxygen (the condensed fluid will normally have about 50% LOX since O2 have a higher condensation temp!) on the bare surfaces. This is a highly dangerous liquid if not handled correctly. Most of you probably know that when using Oxy/Acetylene torches the O2 path have to be absolutely clean from ANY grease or other hydrocarbons. The danger of explosion is very large. And think of LOX as even more dangerous in this respect! The concentration of O2 molecules is almost 1000 times that of atmospheric O2, and then 5 times the concentration of the 200 Bar O2 in the pressurized bottles. I have seen pictures of completely exploded labs not showing care here! Remember that LOX is a low viscosity liquid and will collect at the bottom of whatever contains it, and oils and so on are also lightly to do that. And remember how efficient it is as oxidizer for rocket fuel!
And about the insulation. Most of you use insulation with trapped air bubbles. Remember that this air will be condensed at these temperatures after a while. This will make a vacuum in the bubbles, and since the structure of most plastics at these temps is drastically changed things are starting to change. The insulating properties are decreasing and the phenomenon is spreading.
If you use the way of using completely dried air in the computer to prevent ice to form on the components you are actually making ideal conditions for making LOX inside your container with the dangers that involves. You would not want this to happen! One way to avoid it is to make sure it is boiled of on the CPU or whatever.
Vacuum is probably the best insulation, and I would recommend it as the first choice. Most of you guys have access to vacuum pumps anyway, right :)
One other possible solution is to use Argon as the insulating gas. This is heavier than air and can be trapped in the bottom of a case. And most important of all, it is not explosive, poisonous or whatever and at the same time relatively cheap and easily available.
So chilly1 and all you guys fiddling with LN2 you really should study it more before going ahead. There are real dangers here that are all but obvious if you are inexperienced in this! Remember, this is LITERALLY rocket science! How many of you are rocket scientists? :)
Hi akb1212,
Would you mind filling us in a little with your background, it seems to me as though its scientific or lab tech stuff. And welcome to the forums.
Regards
John.
Um it is realy hard to condense O2 with LN2 b/c the condensing temps is realy close. Another thing is that you will have condensed/frozen water before you get O2. So because of 1. Having a barier of ice between the o2 2. The fact that the temperatures are so close 3. The o2 will probobly evaporate before it collects. 4. The area around the container is mostly N2 due to the fast evaporation of LN2 (namely no O2), you prolly wont see any LOX.
EDIT: I have tried making LOX using LN2 and it didnt work. Thats when TRYING to make it.
Quote:
Originally Posted by JSU
But i guess they are discussing the use of N2 in a cascade not in a container as we have seen many times before. The lowside of a cascade running a extremely lowtemp refrigerant would need to be carefully insulated, that's what i think akb1212 meant :).
But you got a point, there will be a barrier of ice before the O2 will condense on the surface.
The coldest surface on this setup will be the head of the block. The insulation is a problem, I do have access to nitrogenized foam glass insulation if and when we decide to full 24/7 operation. The Ln2 is being moved from the dewer by an open supply loop to the block, The insulation on the 20 min run shrunk up considerably but never dropped below -5C, water was condensing on the outside of it (3/8") and this was standard neoprene closed cell. With the setup on a working computer with it insulated with 1 inch closed cell foam we should have no problem. We are looking for -178C to -184C internal on the processor so the coldest the setup will see will be -195C.Quote:
Originally Posted by akb1212
I have some metering devices (Ln2 specific) for controlling the flow rates and therefore the temperatures.
you do know he is a certified HVAC engineer....right?Quote:
Originally Posted by akb1212
Ooops my bad, I thought that was positive 300K
Thx for the questions, as for the dangers of Ln2 they are very real and this needs to be understood fully before handeling it in any form. Ln2 in a line as I am doing here has it's own set of dangers that need to be addressed, as with any liquified gas in a line aas long as the Ln2 is liquid and at temp there is no problem but almost instantly the line will burst if you close it off on both ends, So every line every valve or device has to have a means of relief, The burst on the copper lines I use are 2000 psi with 1200 psi working pressure max. My reliefs are 20psi leaving me a comfortable margin. If Ln2 contacts skin or soft tissue you will lose it. No second chances with this stuff. This is why I use a tank with a relief and a open pume instead of a compressor.
lol, yeah, they use ln to burn off warts...:P my brother had tons of them:P the doctor did it..not me hehe
nyways, awsome temps chilly1, are u gonna put that on a chip?..
It will be on a chip by next week.
:cool: what chip?Quote:
Originally Posted by chilly1
this is probably the most "evil" rig i have seen.
And i f00king l0ve it !
I dun?t even think it?ll matter what chip, lol, its still gonna run fast?okey, lol, a 500mhz Celeron would be lame?
oh yeah, chilly1 do u have pics of ur setup?
there are some in the start of this thread, but i dare you to look at it,Quote:
Originally Posted by HawainPanda
any moment soon, Aliens will pop out of it and thake a big bite out of Berkut's left legg :D
why thank you! wait till you see the frankenprommie I am working on.... Poor prommie died a premature death, home depot had a sale on food processors, belt sanders and airconditioners, from the butchered remains of these and the contentts of a couple welding shops and supply houses the resurected remains of "Prommie" shall be brought to life!Quote:
Originally Posted by Zejtan