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Thread: What would it take to build a cryogenic cooler?

  1. #26
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    Quote Originally Posted by sjg0 View Post
    How can a vortex tube work properly if the refrigerant is condensing inside the tube? Surely that would screw up the mechanics of the vortex, no?
    But since I saw that you wrote here, I think it best to answer this question for everyone else as well.
    I intend to build another four-socket system. However I'm going to test my four Tyan S2912 motherboards first in the phase-change chilled liquid-cooled arrangement. Actually, those four boards amount to 8 cpus. If I add the Tyan S4992 as previously intended, that will potentially give me 12 processors in the same system.

    I'm really needing to think through my actions more carefully. But I think I want the four Rechi compressors in my first, followed by the Danfoss SC18CLX.2. The Rechi's have 31cc combined, while the Danfoss is only @16cc. From what I understand of how it was explained, having multiple compressors in parallel will raised the volume of refrigerant provided to the second-stage compressor. It would be as though the second-stage compressor were operating under higher atmosphere. See this thread to understand how this was explained to me.
    http://www.spudfiles.com/forums/view...06.html#255906

    Continuing, I think that I will have both stages work together as though they were only one single-stage. Let me see now if I can make sense of this to you. If you think of all the compressors working as the stages of a compressor in a turbine engine, you'll see how there is only one mixture passing through all stages. The only thing that's happening here is increasing the compression ratio of the turbine with each stage. But in my case, this might be like having a two-stage turbocharger with an intercooler between the stages.

    I think I'm about to raise a subject here that I hadn't raised with you before. I have a fascination with vortex tubes. Look them up on Wikipedia. Now I'll continue with what I had already started writing below, before explaining myself here. :-)

    However, if in testing I find that increasing the pressure of the inlet gas of a vortex tube (to @200psi) substantially increases the speed of rotation of the gas within it, I believe the result will be an increase in the performance/efficiency of the vortex tube. The object there being to cool my refrigerant between the first and second stages, without actually using a condenser. What I should see is an even greater transfer of heat from the core column of gas in the tube. Meaning it will be even cooler than otherwise at the same constant inlet temperature.

    But then, if I compound this by also lowering the temperature of the inlet gas, the performance should be even more magnified. I may be able to get sub-zero inlet temperatures on the vortex, combined with the higher rotational velocities induced by the higher pressure. And since vortex tubes can be tuned to produce 90% of the inlet gas as cold outlet gas, I may be able to work with even colder gases than otherwise possible.

    Testing for this would be as simple as running my compressed air through my liquid-cooled heat-exchanger.
    Ok now I'll finish what I started to say above in my email to you.

    Vortex tubes typically have an inlet temperature of 70F, with a working pressure of 100psi. The outlet temperature is @-30F, or lower. I've always wondered what happens if you change either of those.

    1.) Increased pressure
    I believe the vortex tube's function is dependent on the speed at which the gas within it rotates. Vortex tubes are what's known as "forced vortex" devices. Meaning the column of gas within it rotates as though it were a solid slug. The result is the outermost layer of gas draws heat away from the gas at the core. Because the outermost layer is expanding (excited molecules), while the innermost layer is contracting (less active molecules).

    2.) Lowered temperature
    It stands to reason that if the working inlet gas starts out being colder, the outlet gas should also be colder. How much, I don't know. But any improvement in dropping the temperature of the system is better than not doing so.

    Now to answer your question about condensing the gas in the tube. My intent is to vertically orient the tube so that the cold outlet is pointing down. The hot end would be pointing up. With the inlet in the middle on the side.

    As the gas begins to condense, it could easily exit the tube through the bottom. If in my case that gas is dumped into a second-stage compressor, you would have to be careful not to have condensation to the point of being a liquid. My primary intent here is to simply lower the temperature of the gas. I still want it to be a vapor when it enters the second-stage compressor.

    I don't know what the lowest temperature is allowed to be for a compressor intake, provided the refrigerant isn't a liquid. But the cooler the inlet temperature, the less work will need to be done to condense the gas out of the second-stage compressor. I may be able to expand all the component gases in a single evaporator. And that raises another idea which I've yet to describe.

    EDIT: Please see this link to visualize how the refrigerant may exist as both vapor and liquid inside the vortex tube. I'm thinking the central column may be a liquid, while the outer layer may be vapor. But again, I don't want a liquid going into the second compressor. I think what I want is a supercritical liquid, as explained here.
    http://www.youtube.com/watch?v=4gVzL2pc0Gg

    Shingoshi
    Last edited by Shingoshi; 08-16-2009 at 09:32 PM.

  2. #27
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    I think what I want is a supercritical liquid, as explained here.
    You are way off. The supercritical liquid was acheived by raising temp and pressure.

    Try supersaturated vapor instead.

  3. #28
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    Thank you!!

    Quote Originally Posted by ultralo1 View Post
    You are way off. The supercritical liquid was acheived by raising temp and pressure.

    Try supersaturated vapor instead.
    Yes!! You're right...
    I knew when I was writing this that I probably meant something else. I just couldn't remember the chart correctly. And I was too lazy to go back and watch the video.

    My fault!
    Shingoshi
    Last edited by Shingoshi; 08-17-2009 at 09:38 AM.
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  4. #29
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    What are the physical constraints for this project?

    Is this an ATX case setup or rack mount?
    Have you considered the noise from the vortex setup?
    Power draw for the vortex setup?
    Budget?

    I'm all for people trying things but your goal of faster compilation times can be achieved but a processor farm and air cooling, for a lot less risk and money.

    In the first instance I reckon you should test our this vortex business and let us know what happens.

  5. #30
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    i think i have found a soultion


    sorry im taking the plss
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  6. #31
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    This is a Pelican 1780 Transport case...

    Quote Originally Posted by SexyMF View Post
    What are the physical constraints for this project?

    Is this an ATX case setup or rack mount?
    Have you considered the noise from the vortex setup?
    Power draw for the vortex setup?
    Budget?

    I'm all for people trying things but your goal of faster compilation times can be achieved but a processor farm and air cooling, for a lot less risk and money.

    In the first instance I reckon you should test our this vortex business and let us know what happens.
    The system is completely enclosed. The internal dimensions are 42"x22"x15". I already have most of my large components inside the case now.

    And to show the sheer capacity of this case!

    Those clear tanks will be coming out of the case, and possibly mounted outside if used at all.

    1.) The vortex tubes will be muffled by the heat-exchangers they will be dumping the hot gas into.
    2.) There will be two heat-exchangers.
    3.) First heat-exchanger will cool the gas coming from the compressor.
    4.) Second heat-exchanger will be my evaporator, for cooling my liquid.
    5.) The vortex tubes will connect my two heat-exchangers. Refrigerant outlet (of first HX) to Refrigerant inlet (of second HX).
    6.) The cold outgoing liquid from the second heat-exchanger will cool the processors.
    7.) The return liquid from the processors (still being very cold) will enter the first heat-exchanger to cool the gas coming from the compressor.
    8.) The slightly warmed liquid from the first HX will be re-cooled by the evaporator.
    8.) The gas leaving the final vortex tube will be directed back to the condenser.

    That's how all of the heat in the system will dumped outside of the case. Once that gas leaves the condenser, it will come back to the compressor and complete the process.

    Shingoshi
    Last edited by Shingoshi; 08-20-2009 at 11:51 AM.
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  7. #32
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    I must be stupid, I need a drawing, schematic, or something. I cant quit grasp what you are doing. It doesnt have to be a picture or a component layout of the case, just a plain ole drawing showing how you intend for this thing to go together and work.

    Yes I have read the thread.

  8. #33
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    Don't feel bad!!

    Quote Originally Posted by ultralo1 View Post
    I must be stupid, I need a drawing, schematic, or something. I cant quit grasp what you are doing. It doesnt have to be a picture or a component layout of the case, just a plain ole drawing showing how you intend for this thing to go together and work.

    Yes I have read the thread.
    I've spent most of the day trying to think this through. I've been looking for a program to draw my schematics so others could understand what I'm doing. I haven't found an easy program to use. If any of you use Linux (my operating system) and know of a good simple application to do sketches like this, please let me know. I really haven't had need of this before.

    Shingoshi
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  9. #34
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    Do you need a faster rig to compile the appropriate program?

  10. #35
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    Vortex tubes? If you do this I'm pretty sure this'll be the first non commercial time they've been used on computers.

    Good luck!

  11. #36
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    Actually, they already are...

    Quote Originally Posted by [486] View Post
    Vortex tubes? If you do this I'm pretty sure this'll be the first non commercial time they've been used on computers.

    Good luck!
    Vortex tubes are already used for cooling components. I don't think I would be the first to use one in this manner. But if that is the case, that could be interesting. The thing is, I'm also having to incorporate eductors into this design as well. I need the eductors to provide additional circulation in the system.

    I believe I will have all the pressure I need to manage the various components (eductors and vortex tubes). With four compressors in parallel on the first stage, and one compressor in the second stage, I will have substantial volume and pressure to work with. So I shouldn't have a problem here. Especially when you consider that vortex tubes can be tuned to produce 90% of their output as cold gas. That means that with two vortex tubes staged together, you can obtain 99% efficiency from the pressurized system.

    The first vortex tube would only dump 10% of it's input back out as heat. Drawing that heat (which will be much reduced by the temperatures of the first heat-exchanger) back into the first eductor means it will barely raise the temperature of the gas entering the first eductor. And if the inlet temperature of the first vortex tube is sufficiently low, the heat output will be lowered as well. You could wind up with a situation where the "heat" from the first vortex tube is low enough to actually equal (or be lower than) the gas temperature from the compressor entering the first eductor. Granted, that's likely optimistic. But the temperatures could be very close indeed.

    And because the volume of heated gas produced by the first vortex tube is only 10%, there will be a greater volume/mass of gas entering the first eductor from the compressor to cool it. But that cooling would only be required if the vortex tube heat is greater than the motive gas entering the eductor. Driving that combined mixture into the second vortex tube is where the real cooling takes place.

    The heat output of the second vortex tube will only be 1% of the total gas in the system. That's calculating 10% (second-stage) of the 10% (first-stage) loss from the first vortex tube. So that heat can also be reabsorbed into the flow of the first eductor without significance.

    The image below shows the typical operating parameters of a vortex tube. You'll notice that the inlet temperature is given as +70F. I'm hoping that by dropping the inlet temperature, all temperatures in the vortex tube will drop accordingly. I'm also hoping that by increasing the pressure of the inlet, the rotational speed will also be increased. If either of these turn out to be true, I may get an inlet temperature of 0F or lower by cooling the compressor gas with the cold liquid output coming from the processors. Because even with 12 processors in the system, I wouldn't see more than a 40 degree rise in temperature in the cooling liquid. And given that -40F is the working temperature of a standard vortex tube without inlet cooling, I don't think these assumptions are unreasonable.

    All of this means that the temperature of the gas entering the inlet of the second vortex tube would be sub-zero. Even without any of the performance enhancements I've outlined here, a -40F inlet temperature on the second vortex tube will produce extremely low temperatures. And since vortex tubes function much like peltier devices, the cold flow out of the second vortex tube could be under -100F.

    Remember, I 'm driving the second vortex tube with the cold output of the first vortex tube. That means the second vortex tube's inlet temperature will be no higher than -40F. I don't know about the rest of you, but I would be VERY HAPPY with performance like that.

    Shingoshi
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    Last edited by Shingoshi; 08-18-2009 at 08:18 AM.
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  12. #37
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    Just got "Proof of Life!

    I think this post answers all of my needs regarding this project.
    Quote Originally Posted by Stelios View Post
    http://rc.danfoss.com/TechnicalInfo/..._ed400m202.pdf

    Max. condensing temperature continuous (short) °C 50 (60)
    Max. winding temperature continuous (short) °C 125 (135)

    That would be around 325psi continuous and 418psi short .
    The Danfoss SC18CLX.2 will be the final stage. Providing the pressure I need to overdrive the vortex tubes.

    The only thing I need to know now is, whether the second-stage Danfoss SC18CLX.2 in combination with four parallel Rechi compressors in the first-stage can provide 35 CFM.

    Shingoshi
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  13. #38
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    Quote Originally Posted by Shingoshi View Post
    Vortex tubes are already used for cooling components. I don't think I would be the first to use one in this manner.
    I have never heard of anyone using them for computers, there was one guy that talked about it a bit back, but never really did anything of it...

  14. #39
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    Cost may have been a factor...

    Quote Originally Posted by [486] View Post
    I have never heard of anyone using them for computers, there was one guy that talked about it a bit back, but never really did anything of it...
    Are you sure I wasn't THAT guy! I've been on this for a while.

    The idea of spending a lot of money on something you're not sure of, or don't fully understand, can be daunting. Personally, the first time I read about vector tubes I knew immediately how to use them. The only issue for me now is, spending $320 on two tubes. They will have to wait until at least October before I'm able to allot the money to that purchase. But given their importance to my project, I will ultimately have to get them. And the next purchase after that will be my two eductors.

    I can do initial testing with just the vortex tubes. The eductors are also important, as they will provide for the feedback of the expended heated gas. Without them, the system performance will be reduced. Besides, the eductors will provide for silencing the vortex tubes as well. Feeding the heated gas from the vortex tube back into the suction of the eductor will create a closed-loop from which no sound will be emitted.

    It will be interesting to see if the cold output of the second vortex tube is near -110F lower than the inlet temperature, as it is for the first vortex tube.
    1.) First-stage vortex tube: 70F inlet + -110F = -40F cold outlet
    2.) Second-stage vortex tube: -40F inlet + -110F = -150F cold outlet

    I want to take this opportunity to bring something else up. Based on conversations elsewhere, I'm beginning to believe that I won't need to use what we typically think of as a refrigerant. It is my belief that this system can function mostly on the compressed air as the working gas. Since air will not freeze at the temperatures that may be possible in this situation, it seems advisable to use it.

    From chatting with the guys over at Spudfiles.com, I found out that many of them use refrigeration compressors to charge the propellant cylinders for their potato cannons. When doing so, they of course experience oil loss. They simply replace it in time. However, since my system will be a completely closed-loop, I will never have any oil loss or condensation issues that they must contend with. If it turns out that I need to assist in moving oil throughout the system, I can simply add a small amount of propane.

    I may add other gases to assist in the performance of the vector tubes, but air will be doing most of the work. I'm looking for gases with molecular weights that are much heavier than air. The purpose for this is simple. In the vortex tube all of the gas in the system will be rotating at very high mach values. This will cause the heavier gas molecules to be tossed out to the surface of the vortex tube. And the lighter molecules will be forced to the center, by not being able to displace the heavier gas molecules. As a result of this, the heavier molecules will draw off heat at a much higher rate than would be the case with a single gas.

    It is for this reason that I was first thinking of using R-744/Carbon Dioxide. However, drawing from memory I realize that SF6/Sulfur Hexafluoride is even heavier.
    When SF6 is inhaled, the pitch of a person's voice decreases dramatically because the speed of sound in SF6 is considerably less than it is in air. This is a similar effect to that of Nitrous Oxide. As SF6 is five times heavier than air, it displaces the oxygen needed for breathing.
    I may still use R-744 in the mixture, providing stages of separation between both of my vortex tubes. And I can even do something as radical as using R-704/Helium (for being so much lighter than air), to ensure that even lower temperatures can be achieved without ill-effect. The heavier gases will have been removed before having a chance to form ice.

    We'll see if it works out that way or not.

    Shingoshi
    Last edited by Shingoshi; 08-18-2009 at 03:45 PM.
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  15. #40
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    Quote Originally Posted by Shingoshi View Post
    I'm building a system for 24/7 uptime. And the system will have multiple boards in it. So for safety concerns, I want a means to allow for safe shutdown in the event of compressor failure. Given the amount of wattage I'm building for (@8 cpus), the processors would have no reserve to keep them cool in an emergency.

    I was thinking that two benefits might exist here.
    1.) Quicker startup times if any shutdown is required for maintenance.
    2.) It might lower the overall compressor load. Like a tank on an air compressor.
    EDIT: And this ties both of the above into a single concern. It would take a long time to bring the system up to capacity to handle the load of all the processors. It would take even longer if any graphic cards are included. Having the reservoir would eliminate that problem.

    I would use a switch based on my system's activity led, which would turn the tank off only when the computer is actually down. That way if the compressor went offline for any reason, the system would still have a reserve of coolant.

    Shingoshi

    why would you want that, if a compressor fails the liquid held in the resevoir isn't going to cool any load and will run out almost immediately. Also what do you think that would do to your static pressures. You would need a ridiculously huge expansion tank which means a LOT more refrigerant and your talking 4 stages here soo your talking $$$. A lot more then whatever failed- and you would have maybe 10-15 seconds before your temps would be in the hundreds (positive) after the failure. nope, your not going to get to it in time. You would still loose all the $ in comp parts.

    Instead just wire the main ac lines on a relay to the compressor, also a high/ low pressure cutoff to shut off power to the computer.

    P.s. you need any hpco's? (jk)

    cheers\

    p.s.s. i only read the first page or so so im sure this has been covered

    p.s.s.s./edit votex tubes are incredibly inneficient loud et cetera.
    mentally confused and prone to wandering

  16. #41
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    Maybe you should have kept reading...

    Quote Originally Posted by teyber View Post
    why would you want that, if a compressor fails the liquid held in the resevoir isn't going to cool any load and will run out almost immediately. Also what do you think that would do to your static pressures. You would need a ridiculously huge expansion tank which means a LOT more refrigerant and your talking 4 stages here soo your talking $$$. A lot more then whatever failed- and you would have maybe 10-15 seconds before your temps would be in the hundreds (positive) after the failure. nope, your not going to get to it in time. You would still loose all the $ in comp parts.

    Instead just wire the main ac lines on a relay to the compressor, also a high/ low pressure cutoff to shut off power to the computer.

    P.s. you need any hpco's? (jk)

    cheers\

    p.s.s. i only read the first page or so so im sure this has been covered

    p.s.s.s./edit votex tubes are incredibly inneficient loud et cetera.
    I'm pretty certain I said I wanted a reservoir for the sage shutdown of the system. And your argument doesn't take into account the size of the reservoir. It's no different than the size of the battery in your UPS. The larger the battery, the longer the system can run before shutting down. So, the larger the tank, the more reserve you have to work with. And I don't need a lot of time here. Typically, Linux systems shutdown very fast.

    And then there's the issue of waiting for the cooling system to come up to capacity. Looking at freezers intended for deep cooling, they take a long time to reach full operational status. Having a reservoir (in this case a dewar) means that the system can startup sooner than otherwise. The reservoir would then be replenished while the system is running.
    And when have you ever seen a scuba tank filled with refrigerated liquid-coolant evacuated in 10-15 seconds? Yeah, right!!

    Shingoshi
    Last edited by Shingoshi; 08-18-2009 at 07:00 PM.
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  17. #42
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    Just to satisfy my curiosity, what is going to create the pressure differential to move the refrigerant from this gigantic reservoir through the metering devices and through the evaps when the compressors are off? Depending on the system equalizing itself? Not certain which gas you have planned for this reservoir concept, but like Teyber said have you accounted for the expansion of said coolant when it isn't chilled? There is a reason we try to keep our post-HX volumes to a minimum, for a scuba tank of liquid R744 I hope you have a couple dozen scuba tanks as expansion tanks

  18. #43
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    I think you are a confused on numbers your giving on vortex tubes..........You say 90% is cold or can be realize to get 90% cold cooling power out the cold side ,90% of the mass flow goes out the hot side. So you have 10% mass flow providing the 90% cooling power. Its cold air,just not a high volume of it.

    I did afew short test with air @ 250psi ~35cfm and reached -30c on the cold side but only ~5cfm was discharged,the other ~30 cfm went out the hot side. Can't recall the maximium temperature delta between the hot & cold sides., and I never calculated the BTU's of the cold side.

    The lower the temperature on the cold discharge,the lower the mass flow on the discharge & that equals less cooling power.

    I Tested a few with air from 100psi to 500psi (limit of my air compressor) and found that even that my compressor had a refrigerated dryer ,over 150 psi they iced up since my dryer wasn't rated past 17cfm @ 175psi. so all the tests over 200 psi I bypassed the dryer so not split the tubes and the test runs only lasted a few min. before ice froze the outlet.

    Previously I only seen them used on air but theorized using a refrigerant like R22 would produce a better COP than air.


    They are no miracle device like you think, I was looking @ gaining a few % in performance by using a gas other than air .There not going to justify the cost & added complexity and I think your calculations and understanding of performance is way off.
    The Laws of Thermodynamics say:

    Zeroth Law: "You must play the game."
    First Law: "You can't win."
    Second Law: "You can't break even."
    Third Law: "You can't quit the game."

    Do you wanna Play Thermodynamics ???????? I forgot "you must"

  19. #44
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    Thanks wdrzal!!

    I was wondering when you would say something!
    Quote Originally Posted by wdrzal View Post
    I think you are a confused on numbers your giving on vortex tubes..........You say 90% is cold or can be realize to get 90% cold cooling power out the cold side ,90% of the mass flow goes out the hot side. So you have 10% mass flow providing the 90% cooling power. Its cold air,just not a high volume of it.

    I did afew short test with air @ 250psi ~35cfm and reached -30c on the cold side but only ~5cfm was discharged,the other ~30 cfm went out the hot side. Can't recall the maximium temperature delta between the hot & cold sides., and I never calculated the BTU's of the cold side.

    The lower the temperature on the cold discharge,the lower the mass flow on the discharge & that equals less cooling power.

    I Tested a few with air from 100psi to 500psi (limit of my air compressor) and found that even that my compressor had a refrigerated dryer ,over 150 psi they iced up since my dryer wasn't rated past 17cfm @ 175psi. so all the tests over 200 psi I bypassed the dryer so not split the tubes and the test runs only lasted a few min. before ice froze the outlet.

    Previously I only seen them used on air but theorized using a refrigerant like R22 would produce a better COP than air.

    They are no miracle device like you think, I was looking @ gaining a few % in performance by using a gas other than air .There not going to justify the cost & added complexity and I think your calculations and understanding of performance is way off.
    This always bugged me! I wrote one of the companies some time ago, and they never responded. That would have cleared all of this up to begin with. I kept wondering if I was reading this correctly or not. It just kept coming across as though most of the air could be produced as cold. I guess it kind of makes sense now.

    In order to draw off more heat, you'd have to release more air through the hot side. And with that high a volume of hot air, you would never see the performance required for heavy cooling. I guess if I were made of nothing but money, I could always drive that hot air through a turboexpander. But I don't have that kind of money. Thanks for saving my pocketbook!

    But now let me ask this.
    1.) Were you afraid of splitting the vortex tubes?
    2.) Did the cooling effect increase with inlet pressure?
    3.) Were the driers or the tubes icing up internally?
    4.) Was this tested in a closed-loop? Or were you letting the air escape to atmosphere?
    5.) Did you use a heat-sink on the hot end? I've read that's what you're supposed to do.
    6.) Was the freezing due to moisture in the air supply? Because a closed-loop would have no moisture in it.
    7.) Were the vortex tubes exposed to the ambient atmosphere?
    8.) Did you make any attempt to insulate the vortex tubes?
    9.) Did you make any attempt to precool the inlet temperature?
    10.) What would happen by cooling your air supply through a HX?
    11.) What about using a gas like Helium?

    About my last question. If you used two gases where one molecular weight was much heavier than the other, wouldn't the heavier gas draw off more heat in the vortex tube while needing a reduced mass?

    But most importantly, I need to know if your test system was an open-circuit? That would influence things and introduce complexities that wouldn't occur in a closed-loop.

    Thanks,
    Shingoshi
    Last edited by Shingoshi; 08-18-2009 at 10:50 PM.
    The distribution of knowledge must not be the commodity of tyranny.
    Solution: The immediate equalization of all knowledge among all beings.

    Expand your mind, advance our world!
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    http://www.linuxquestions.org/blog/shingoshi-297853/

  20. #45
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    Wdrzal, what if we were doing the wrong thing?

    Both of us took to the idea that vortex tubes would be good at producing cold. And in that, we were both wrong, as you have already proven. So what would happen if we concentrated on the things that everyone here knows they're good at. Producing heat and noise.
    A turboexpander, also referred to as a turbo-expander or an expansion turbine, is a centrifugal or axial flow turbine through which a high pressure gas is expanded to produce work that is often used to drive a compressor.[1][2][3]

    Because work is extracted from the expanding high pressure gas, the expansion is an isentropic process (i.e., a constant entropy process) and the low pressure exhaust gas from the turbine is at a very low temperature, sometimes as low as −90 °C or less.

    Turboexpanders are very widely used as sources of refrigeration in industrial processes such as the extraction of ethane and natural gas liquids (NGLs) from natural gas,[4] the liquefaction of gases (such as oxygen, nitrogen, helium, argon and krypton)[5][6] and other low-temperature processes.
    And unlike the vortex tube, all of the gas going into a turboexpander is coming out cold.

    Let's focus for a moment on the amount of heat vortex tubes can produce. And the intensity of sound isn't to be ignored either. Because sound at high volume is nothing more than strong pressure waves. Pressure waves can be amplified as well. Instead of trying to lower the inlet gas temperature going into a second stage tube, what if we concentrated on raising it. Simply done by directing the hot exhaust of one vortex tube into the inlet of another.

    Vector tubes will raise the temperature of the inlet gas from 70F, to 230F. How much more would the noise be amplified? It produces more mass of heat than it does of cold. The comparison is a 160F rise of heat versus 110F drop in cold. So what would happen if the second vortex tube's inlet was 230F? What would the outlet temperature be then? Maybe 390F? Have you ever heard of steam detonation? We wouldn't have to worry about the sound level of the first tube, because it would be silenced by the second. If we then drove the heated outlet gas of the second vortex tube through a venturi injector and into a turboexpander, we would have a very high flow rate of heated high-pressure gas. Which could then be expanded and cooled.

    The venturi injector or eductor would create a very strong suction. In the process the mass of the flow would be increased. The turboexpander would receive an even larger mass of gas entering it. So, can you stage turboexpanders, the way you can stage venturis and vector tubes? The industry is already aware of staging injectors to increase the power of their suction. By doing so, they are able to create very powerful vacuums. Remind me here, what happens to the temperature of a fluid subjected to an extreme vacuum?

    Would it be possible to create an alternative of a multi-effect vacuum generator? We would have both the heat and the suction to create one. Again, all of this could be moot. Because if turboexpanders don't work the way I think, we might still wind up producing more heat than cold. I have to look closer at the mechanics of turboexpanders to see how they really work. Having been wrong once, makes me not want to do so again. So if you know something here that I need to, fill me in. Please!

    My line of thought here is on:
    1.) Turboexpanders
    2.) Thermoacoustic refrigeration
    3.) High-energy vacuums.

    Now I'll go back and crawl into my corner.
    Shingoshi
    Last edited by Shingoshi; 08-19-2009 at 12:55 AM.
    The distribution of knowledge must not be the commodity of tyranny.
    Solution: The immediate equalization of all knowledge among all beings.

    Expand your mind, advance our world!
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    http://www.linuxquestions.org/blog/shingoshi-297853/

  21. #46
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    I want to take this opportunity to bring something else up. Based on conversations elsewhere, I'm beginning to believe that I won't need to use what we typically think of as a refrigerant. It is my belief that this system can function mostly on the compressed air as the working gas. Since air will not freeze at the temperatures that may be possible in this situation, it seems advisable to use it.

    However, since my system will be a completely closed-loop, I will never have any oil loss or condensation issues that they must contend with. If it turns out that I need to assist in moving oil throughout the system, I can simply add a small amount of propane.

    Air + Propane + closed loop + heat + pressure= Darwinism in action

    Please try this and tell us the results.

    You seem to be very adept at googling. We have all been impressed with your search engine skills.

    Have you ever worked with phase change? Have you ever worked with refrigerants? Have you ever built a Phase unit, repaired an AC unit, put freon in your car?

    You seem like an inteligent person, but you really have no idea what you are talking about here. You are jumping from one thing to the next with out a basic understanding of the refrigeration system or the various components needed. You have been told by several people here that your idea is a waste of time for the application. I am no computor person but I know enough that when these people tell you that it is a nogo then it is a NOGO.

    My line of thought here is on:
    1.) Turboexpanders
    2.) Thermoacoustic refrigeration
    3.) High-energy vacuums
    The expense is not worth the return.

  22. #47
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    I missed the simple solution....

    Yeah, I was just blowing a bunch of hot air before. Maybe this will cool things off!

    1.) The hot end of the vortex tube MUST be completely sealed.
    Doing that allows all of the working gas to produce cold.
    2.) The hot end MUST dump all of it's heat into a heatpipe.
    The heatpipe MUST be a thermosiphon.

    A thermosiphon requires no mechanical energy to dissipate heat. The fluid of the thermosiphon needs to be extremely volatile. A mixture of acetone and ethanol would work just fine for this. As long as you can dump the heat faster than it's generated, the vortex tube will function properly. Producing nothing but cold gas.

    Shingoshi

    Documentation:
    AN INVESTIGATION OF THE EFFECT OF THE HOT END PLUGS ON THE ....
    Refrigeration Patent
    Experimental Study the Ranque-Hilsch Vortex Tube
    Dual Vortex Tube
    Last edited by Shingoshi; 08-19-2009 at 02:44 PM.
    The distribution of knowledge must not be the commodity of tyranny.
    Solution: The immediate equalization of all knowledge among all beings.

    Expand your mind, advance our world!
    >=(o_6)=>
    http://www.linuxquestions.org/blog/shingoshi-297853/

  23. #48
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    Quote Originally Posted by ultralo1 View Post
    You seem like an inteligent person, but you really have no idea what you are talking about here. You are jumping from one thing to the next with out a basic understanding of the refrigeration system or the various components needed. You have been told by several people here that your idea is a waste of time for the application. I am no computor person but I know enough that when these people tell you that it is a nogo then it is a NOGO.
    Oh thank you for write this. That are exactly my thoughts!
    This thread is a waste of time.

    At first, build a normal single stage and then think of building such a huge system. And please, say on the ground...
    Quote Originally Posted by Xeon th MG Pony View Post
    ....and avoid being a total venting loser!

  24. #49
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    Quote Originally Posted by ultralo1 View Post
    Air + Propane + closed loop + heat + pressure= Darwinism in action

    Please try this and tell us the results.

    You seem to be very adept at googling. We have all been impressed with your search engine skills.

    Have you ever worked with phase change? Have you ever worked with refrigerants? Have you ever built a Phase unit, repaired an AC unit, put freon in your car?

    You seem like an inteligent person, but you really have no idea what you are talking about here. You are jumping from one thing to the next with out a basic understanding of the refrigeration system or the various components needed. You have been told by several people here that your idea is a waste of time for the application. I am no computor person but I know enough that when these people tell you that it is a nogo then it is a NOGO.



    The expense is not worth the return.
    You're much more polite than me
    Last edited by [XC] gomeler; 08-19-2009 at 09:34 AM. Reason: spelling #fail

  25. #50
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    You guys are cracking me up...
    Never empower an idiot with a response....

    http://en.wikipedia.org/wiki/Troll_%28Internet%29

    Seller/Buyer Reputation:
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    Ebay: {Family Account} Kasyg3 http://myworld.ebay.com/kasyg3/
    Ebay: {My personal Account} Sdumper http://myworld.ebay.com/sdumper/
    iTrader: http://www.blazingpc.com/forum/itrader.php?u=28

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