ln as refrigerant

[epion2985]

ln as refrigerant. I know it has been discussed before but I couldn’t really find much information about it so I wanted to start a little discussion. Pull a vacuum and charge with ln. Anyone tried it yet? On paper it looks like a great refrigerant. What compressor oil would you use? Any reason why it hasn’t been done yet?

[n00b 0f l337]

Multiple stages and critical pressure. Goign to need a 4-5 stage cascade. Oil seperation would be key as well.

[epion2985]

...? why, ln is liquid at 1 atmosphere right?

[Carlz0r]

...? why, ln is liquid at 1 atmosphere right?
Only after it has been extremely compressed and stored in special dewars. At regular room temp nitrogen is not liquid. Correct me if I'm wrong. Critical point of -146.9c.

[epion2985]

Thats interesting. From the ln pot experiment observations I see people open up the jugs and just poar the ln in to their pots. Since they are holding it and poaring it looks like the container is neither cold not under pressure.

[DBlue135]

the jugs are very well insulated. They are not cold on the outside but they are extremely cold on the insisde

[epion2985]

Why would they be cold on the inside. Only way I see it ff the jug is closed and ln evaporating, pressure will build up to very high levels and yet you see people poar from an open container, ie at 1 atmosphere. I am sure as you are holding the container and poaring it is evaporating so it gets cold, but prior it shouldnt be. I mean it just doesnt make sence. If its cold its becuase its boiling, if its boiling then pressure will rise very high as the jug is closed. And pressure is not high since people just pop them open and poar. Basically if the jugs are very cold inside then that means its evaporating, meaning it can not be closed really because you would get high pressures which it doesnt seem you do since people just open them up and poar.

[the_new_guy]

there are high pressure release with releases pressure ever now and then.

[epion2985]

bah! shame, I suppose it sounded to good to be true, ln as a refrigerant in first stage, now that would be the day we all order some pizza and beer and part :(

Wonder if there are any nice refrigerants out there that have critical pressure under ~250psi and critical temperature no lower then average room temperature ~28C with a boiling point below -50C and decent capacity, ie usable for single stage units. I would gladly pay ~$600 for only a few pounds of a refrigerant like that.

[the_new_guy]

r116

[epion2985]

not really.

Critical temperature : 19.7 °C (thats way lower then average room temperature, unlese you live in canada with windows open)
Critical pressure : 29.8 bar (thats 435 PSI!!!)
Boiling point (1.013 bar) : -78.2 °C (nice bp though)

[lma01]

ES 20 should fit your goal:
Critical pressure: 585PSI (40 bar at least!!!)
@ Critical temp: 67.3°C
NBP: -64.8°C

Very high pressured @ very High temperature.

[_HL4E_HalfLife_]

Puron (R410) bp is like -51c, R402A bp is -49.8c i think, thats close enough to -50c:D

[lma01]

R504: -57.7°C NBP
Critical point 644PSI@62.2°C

[Xeon th MG Pony]

not really.

Critical temperature : 19.7 °C (thats way lower then average room temperature, unlese you live in canada with windows open)
Critical pressure : 29.8 bar (thats 435 PSI!!!)
Boiling point (1.013 bar) : -78.2 °C (nice bp though)

Hey now, It's not all ways that cold here! I how ever do like an Average room temp of 19C :) it's the perfect temp :D

How ever I keep most my refrigerants in the fridge lol

[wdrzal]

...? why, ln is liquid at 1 atmosphere right?


No, 78% of the air you breath is nitrogen, in gasous form ,luckily.

[epion2985]

ES 20 should fit your goal:
Critical pressure: 585PSI (40 bar at least!!!)
@ Critical temp: 67.3°C
NBP: -64.8°C

Very high pressured @ very High temperature.

Thats not my goal, where did you get that idea? I want low BP and low pressure... There are pleanty of low bp high pressure gasses....

R504: -57.7°C NBP
Critical point 644PSI@62.2°C


again to cp to high!??? where the hell do you see a compressor that will handle 650PSI thats reasonable to use in a pc.........


I said CP needs to be under 250PSI not over...

[n00b 0f l337]

Erm thats at 62.2C, its more of a 2nd stage gas or an SLHX gas.

[wdrzal]

Mechanical refrigeration has been in use for over 100 years,do any of you guys think by looking at boiling points of gases listed on the peridoc table and no one uses think all the engineers just must have missed the perfect miracal gas???? I doubt it. Expermenting mixing gases that you don't know the outcome to can be deadly.

[Xeon th MG Pony]

Ya, sort of like using NitrusOxide, But hey, at least you'll go out with a bang! and have a blast all at once! :D

[epion2985]

exactly, those gasses are ridiculous for single stage units.

no I dont think the miracle gas was missed. I think by mixing and experimenting I am sure companies and people came up with some good mixes. What I do think is that alot of knowledge is unavalible or unfound by most people. There is a good sticky on ProCooling forums about how there are great breakthoughs but poeple dont hear about it because it stays isolated on sertain sites no one knows about etc etc, and by the time someone does find it its old news. I am sure there are some great refrigerants out there, esspecialy in comercial use that most people dont know about, or havent figured out yet. Chemical forumulas and prosseses for nylon were always there yet they werent discoved untill the 19th century, same goes for most things. Just because you have numbers on a peace of paper doesnt mean you know everything there is to know. You can only imagine how things change in just 5 years alone, especialy now a days. The reason I asked is because people, especialy hereare always tinkering and trying new ideas, you never know when the next breakthough will come.

[Xenogias]

I see your point epion, but its hard to say that miracle gasses can exist still with basic single compressor systems. I think the most new gasses like r410 can hope to do is shave off a couple deg C from their predecessors--At least with the same refrigeration systems. I'm sure something could be done on the molecular level or with lazers or controlled chemical reactions that might work better, but no one seems to want to get into the heavy science of it (I sure don't) just tweak the old single compressor system and blend gasses. I just don't think there are substances in the physical world that could have the properties you describe. I bet it breaks some basic rules and limitations that I'm too tired to try to bs about =/

sounds like you want an autocascade...

[Xeon th MG Pony]

For the love of Halucigens CAPITALIZE "LN" perhaps I'm to stuck to conventions but it confusing the hell out of me reading your posts when you use lower case where capitles are meant to be. Thats an Importand distinction that must be made!

[Sneil]

lol, omg gimme a break man

[Xeon th MG Pony]

lol, omg gimme a break man


I am! I'm not asking to put the 2 in now am I?

LN2 it's diotomic when in liquid state! I'm just asking for proper conventions to be some what followed to make it easier to understand.

[lma01]

exactly, those gasses are ridiculous for single stage units.

.... I think by mixing and experimenting I am sure companies and people came up with some good mixes....

Actually, ES 20 is a mix R-23/125/143a (20%/36%/44%). Besides, it is useable in a SS with slhx. No miracle, low BP is always meaning high pressure. A rotary will do the job well.

[epion2985]

no he is right, LN2 it's diotomic when liquid, I should atleast add the 2 I know better. My bad.

[Hound]

im going to be a tard, and ask this question, wtf is the critical point, and why is it useful...i have a vague idea, but too vague lol

[epion2985]

Critical pressure is the pressure below which no matter how cold you get the gas it will not condense.

Critical temperature is the temperature above which no matter how high the pressure is the gas will not condense.

Critical point is the combination of those two, basicaly the point after which you can condense the given gas.

[wdrzal]

Critical point:
The thermodynamic state in which liquid and gas phases of a substance coexist in equilibrium at the highest possible temperature

[Hound]

so anything lower then the critical point, and it will condense?

any guides that go into the scientifics of phase change, or only a serious amount of research?

[epion2985]

Lower relative to what? Lower on the temperature axis yes, lower on the pressure axis no.

Serious guids to phase change science? lol... Just open your physics/chemistry books and look up Change of State of the Matter. Not much to it, to the consept atleast. Things boil, things evaporate, things condense, things frezze. You learn most of it in middle school. And hopefully the rest in college as far as energy and heat goes. It takes energy to boil a liquid, the energy we use is the heat from the cpu. Heat is a form of energy. Once it is used up for boiling something its not there anymore. The First Law of Thermodynamics (Conservation) states that energy is always conserved, it cannot be created or destroyed. It kind of moves around lol. Refrigeration is just a really good way to move it.

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