Autocascade Drawings

Argon saturates like salt into water.

Im not too sure about this type of autocascade design with 2 stages and phase sep. I did not expect the lowside pressure to be this high. looking at what I did sofar you wont get lowside below 0 bar meaning idling temps in the -70's. What is load then? -55 -60c? By the way this rotary pulls vacuum with straigth R402a I should see -70c anyways and at least -50c -55c with 200w load.

Is this kind of design worth it?

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Originally Posted by johann

Im not too sure about this type of autocascade design with 2 stages and phase sep. I did not expect the lowside pressure to be this high. looking at what I did sofar you wont get lowside below 0 bar meaning idling temps in the -70's. What is load then? -55 -60c? By the way this rotary pulls vacuum with straigth R402a I should see -70c anyways and at least -50c -55c with 200w load.

Is this kind of design worth it?

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For example, with 3/4HP rotary, R290/CO2 I`ve got -65*C @ 155W of load. Suction pressure - 1bar

It may not seem worth it, but the unit itself would be more effieicient hopefully. THe true benefit I see comes in when you run a 3rd stage (not counting an auxillary cooling gas)

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Originally Posted by LukeXE

For example, with 3/4HP rotary, R290/CO2 I`ve got -65*C @ 155W of load. Suction pressure - 1bar

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Luke i see in some other threads your hx temp is -50c how do you get it that cold? I cant get it close to that. I got it to -20c on the hx exit then it just goes up and up. Evnetually I could not get it colder than -5c. I gave more propane, more r23 until pressure n the highside was out of control. evap stays -65c at about .5 bar.

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Originally Posted by LukeXE

Unknown_road, what gases are you using in your Auto-c ?

I`m trying with R290/R600/CO2/R1150, but in next few days Johann should send to me some R23, maybe it will help. I think that CO2 isn`t the best gas for autocascades, is it ? :p

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I've tried r600/r507/r1150 I'll replace the ethylene with ethane and see if that works when I have some more time (probably about 10 years from now.)

Maybe I'll make it r600/r290/r170 but maybe that's too much of an alkane party.

@Tom: KJ/kg doesn't say anything, you need "kJ/Liter".

@nol: salt disolves, the molecules fall apart :slap:

Okay okay you know what I mean,
As the r14 gets cold enough, and the argon gets cold enough, it dissolves into the r14. It then boils out when it enters the low side pressure.

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Originally Posted by johann

Luke i see in some other threads your hx temp is -50c how do you get it that cold? I cant get it close to that. I got it to -20c on the hx exit then it just goes up and up. Evnetually I could not get it colder than -5c. I gave more propane, more r23 until pressure n the highside was out of control. evap stays -65c at about .5 bar.

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Do you have SLHX before phase separator ? If not, install it. This will solve all your problems I think :)

Yeah the SLHX, or auxillary cooler, can increase your capacity and separation. I remember when Luke and I first chatted about that and it did turn out to help alot.

Yes, it`s helping a lot with good separation. The best in this idea is that some of condensed lowstage gas (CO2/R23 etc) is going to the HX, lowering its temperature a lot at idle ! At load maybe not that much, but still it helps with capacity, like NoL said. You will see only good sides of that solution, it won`t hurt the unit for sure :)

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Originally Posted by Unknown_road

I've tried r600/r507/r1150 I'll replace the ethylene with ethane and see if that works when I have some more time (probably about 10 years from now.)

Maybe I'll make it r600/r290/r170 but maybe that's too much of an alkane party.

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Hmm, try to change R507 with something else, I tried with it but no good results at all...I`m preffering R290 :toast: I will try to do some tests with R22.

R600/R290/R22/R23/R1150/R14 mix, hehe, what results I should expect with that mix in 2 stage autocascade ? (two separators) :toast: :banana:

Only one other thing I dont think you've tried yet Luke, the subcooler? Or possibly the solenoid on/off switch which should definitly help.

EDIT: More separators I think, one to get the r600 liquid out to the auxillary cooler, one for hte r290/r22 to the hx, one for liquid r23/r1150. Then possibly a subcooler stage.

I still can`t understand the subcooler idea :|

Hop on AIM or msn :)

Ok, I got it. Thank you :*

No problemo Luke ;)

So, when we will do next autocascade competition ? :toast:

Hahha itll be co2 again Luke if we do, and I can't wait as this time Ive got parts and such.

I would start new competition on 1 of April and end on 1 of September. 6 months of fun :p I must talk about that with Jinu and Runmc.

Of course, CO2 will be ! It must !

I'd be in, nothing colder in the units then co2 though, anything warmer than that call it fair game? That excludes r23, r508a-b, and r13 and most other normal 2 stage gases.

We should stay with only CO2. It`s the most fair low stage gas for everybody, everyone can buy/got it for really funny money and with it everybody can obtain some good results. No dry ice problems when unit will be properly designed.

Yup! But that doesnt mean we should limit ourselves from things like r600, r11, or r21.
I'm sure I can take you on Luke :P

Of course, all gases are OK, mixes are always good. But lowstage = CO2 only :).

Hehe

O I think this year might be very eventful. Maybe we'll see some cleaner units :P

I hope, that we will see a lot of wonderfull builds in this year :) Can`t wait to start competition btw. :woot: