# 4 chamber Semi-active Fog Chiller-Let the Insanity continue (You'll like this one)



## niblique71

In my never ending (almost insane) quest to produce a better fog chiller, I began to question some of the concepts that I used in my own Scratch Built Fog Chiller which has become known at the "Cube chiller". It's a GREAT Chiiler with Proven effective results.

I've been trying to read the entire "Vortex fog chiller thread" but it so long that I've had a hard time getting through the entire thing. It has some GREAT information so far And I'm looking forward to finishing the read. A few universal flaws of all Ice type fog chillers began to emerge as a theme. They all EAT a LOT of ice.

I run my (3) chillers a LOT during the Halloween season and racked up a $350 bill between Ice and Dry Ice over a few weeks. If you Just use your Cube (or similar) chiller for one night, than it's No big deal (Cheap).

THE GOAL:
Make a reasonably priced (Not Cheap) chiller that will do the job using a fraction of the Ice/ Dry Ice.
Make it in a size and shape that it can easily be incorporated as a monument base or other halloween related prop.
Make it easy to Load up with cooling materials.
Make a chiller that will work in colder climates where you have to UBER Chill the fog to get it be "Ground hugging"

THE CONCEPT:
Use "free" cold halloween air to assist in the cooling process.
Use "Stages" to cool the fog in a progression from warmer to colder.
Totally Contain the fog from entrance to exit. 
Ice and Dry Ice can be added during fogger activity.
Self Feeding Ice/ Dry ice reserve for lower nightly maintenance.
Capture the negative calories of the melted ice (Still has cooling properties)

STAGES:
Chamber 1 -Expansion Chamber
Chamber 2- Active air cooling (fan Assist?)
Chamber 3- Ice bath (75% Ice and 25% Water)
Chamber 4- Dry Ice, or Dry Ice and water ice mix

THE PROJECT (In Progress and UNTESTED):

Here is what I came up with so far. 








Hot fog will enter the expansion chamber (unfinished) in the foreground using 2"PVC and a 90 degree "Up Pipe".

The hot fog will expand. Via pressure it will be forced into the second "Air cooling" chamber through the 6 holes at the bottom of the panel in this view.

Again using the positive pressure from the fog machine, it will be forced up through the series of 1/2 cooper pipes that will be kept cool using a built in fan.

At the top of that chamber the fog will be forced into a "matrix" of copper tubes (Chamber 3) that submerge into an "Ice Bath".

Once the fog exits the ice bath, it will pass through a narrow transfer chamber to the Dry Ice chamber where it will recieve it's final cooling effect.

Add a plastic bag at the exit and there should be some very frigid fog carpeting the neighborhood.










Here's a good shot of the "Air cooling" chamber yet to be enclosed. A Fan will be mounted in a chamber on the right to force cold "ambient" air through the first set of copper pipes.









Partially enclosed. That thin slit is a transfer channel between the Ice bath and the dry ice chamber.









Here it is more or less complete, I still have to decide weather I want to put the air cooling fan on the Top (inside a monument), or on the side. The "Ice access lid isn't installed yet. I'm going to use that lid area as a "Hopper". There will be a "Cube" of Ice and dry ice (Separated) that will rise above the main body of the chiller inside a monument. THis will allow me to "Overload" the cooling areas and let the Ice melt down. My hope is that the "Ice chamber" will hold water so I can get really good contact with the small copper pipe matrix.









I just finished this stage of the chiller this evening. EVerything you see in this last picture is glued and sealed up. Nothing can be removed (except the ice hopper/lid, not shown). The entire thing is air/water tight (hopefully). The fog won't make direct contact with the Ice but will rely on trhe thermal properties of the copper to transfer the cold..

I'll let the PL Glue cure up and give it a trial run tomorrow or sunday. I want to test it while the weather is still cold, so I can get a good bearing on it's effectiveness. Of course if I lived in a warmer area, I wouldn't need to chill the fog to such an extreme to get it to stay on the ground.

WISH ME LUCK


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## halstaff

Looking forward to seeing the results of your tests.


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## niblique71

Here are some more "in progress" pics not in any particular order. Damn, I hope this thing is "Air tight".



















Note the Petcock in this picture. It to relieve some of the melted icewater and let the fresh ice drop down to replace it. That's the theory anyway. Tests soon.


















I realize that I might have some fog "Backwash" with this design (fog drooling out the entrance pipe between burst). I've accounted for that for future impovements if the design shows promise. It's Just a prototype for proof of concept. If it works as planned, I'll be thrilled.

BTW.. Copper is SOOOO DAMN EXPENSIVE Now!!!!!


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## Wildcat

Can't wait to see it in action. You've become obsessed with cooling fog. Our very own Mr. Freeze. LOL.


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## niblique71

OK, I could't wait. This concept has been festering in my brain for more than 3 years. I disobeyed my own rules and tested this thing before the glue fully cured with "JUST A FOGGER"...... NO ICE.... 28 degrees...I was just checking for leaks and it already has a STRONG indications that the design will be a winner, In fact I might have overdesigned it. Yea, I created a few leaks because the pressure was too great for the curing glue. It forced me to add a few deck screws to pull the thing tight, but if I was patient that wouldn't have been an issue. I'm TOTALLY Pumped!!! With the Ice/ Dry Ice combo this thing should really kick butt. The volume of fog output is a little less than I wanted.... but with some tinkering I think I can get that down pat. AND... the "Air cool" chamber was blocked off since I hadn't decided where I want to put the fan. NO Kidding, I'm PUMPED!!!

I "Cheaped out" in the prototype, opting for 3/8" OD flexible copper pipe. I should have used 3/8" ID or a little larger for the ice bath area. I can tell that the restriction of the flow is at it's limit even though it worked just fine with a 1000W fogger. Still cool though, it's proof of concept so far untill further testing..


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## steveshauntedyard

Nice! This thing looks really cool.


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## Lunatic

Wow Nibligue! Been busy there? Lot's of thought and time involved in that one my friend. Very nice to see your enthusiasm. 

I was involved in that Vortex chiller thread years ago so I have lots of respect for your effort in this project. The thread is ridiculously long to read and I wouldn't want to do it but there's some great info in it. We can thank many people for developing the "Reverse Vortex" concept. But now it appears that you have sparked a new reason for a long thread. 

Can't wait to see your results after loading that sucker with some ice. I love the concept of different cooling chambers with the final dry-ice cooling. 
Good luck!


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## niblique71

It's 34 degrees out and a little windy, but I decided to give the chiller a try. I don't have any dry ice for the final chamber, but I filled that with water and Ice.

Good news part 1, The chiller does hold water in both chambers so I'm happy about that part.

The bad news is that it's 34 degrees out. I don't think I can chill the fog to a low low enough tempature using just regular Ice. The design appears to be working as the fog comes out thick and white and has ample volume. It just doesn't hug the ground due to turbulance and a lack of a tempature differential. In order to really test it I'll need about 2lbs of dry ice and a slightly warmer day. I might give it a try indoors just to see.

Halloween night here is typically 45-50 degrees. My guess is that I'll need at least a 15-20 degree difference (or more) between the ambient air and the chilled fog to get the desired results.


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## Vlad

I think you should have built in an ice cube maker.


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## niblique71

Vlad said:


> I think you should have built in an ice cube maker.


Perhaps your not far from the truth Ken. That's why I love your neverending sarcasm. Perhaps we can discuss some modifications when we get together next weekend. I didn't do this project to impress anyone. I had a concept that I wanted to prove or disprove.

I did some more testing last night and the concept DOES work. Granted it did NOT outperform my "reverse Vortex" in this current version. I used Ice in both chambers and did get low lying fog. It just wasn't that "Uber Chilled" fog that I was hoping for. With 2-3 lbs of dry Ice in the final chamber, I think the results will be comparable to the reverse vortex. The design shows promise, but needs some improvement to perform to my expectations.

OBSERVATIONS:

1) There are some chamber conflicts that I need to resolve to get optimum performance. But I knew this when I designed this version.

2) I feared that the expansion chamber was too small for a high wattage fogger. I think a slightly larger expansion chamber would create more fog volume. My results were't bad though.

3) I need a little more surface area for the pipes in the cooling chambers. This can be accomplished by Crushing 1/2" pipes into flattened ovals. This will give more surface area without restricting the flow much. Also by adding more pipes the flow will slow down even more and capture more "Cold".

4) I should have gone with my instincts and used 3" inlet pipe instead of 2". I just don't think enough outside air is being drawn into the chiller. I can always add a 2" to 3" adapter afterwards which might help with expansion.

5) I feared that the chiller would "Oooze" out fog between bursts since it's not relying on gravity like a reverse Vortex. It didn't. That must be due to the "90 degree up-pipe", and a little bit of convection.

6) Another concept occured to me that I haven't (yet) seen discussed in the "Vortex thread". Any chiller that makes direct contact with Ice does have this distinct advantage when cooling a gas (Fog). When the Ice melts it actually briefly get's colder as it changes states (I think I have this right??). You will also be taking advantage of some of the melted ice changing to a gas (evaporating a little bit)which contribues a little to the cooling as well. Conversely when you "Freeze" water into Ice, it releases heat. I won't be able to take full advantage of this principal since it's an enclosed system. My second test didn't use water in the main cooling chamber, just some leftover snow (Slightly melted). I think that the snow making contact with the copper tubes, and then melting a little bit actually dropped the tempature in the chamber by a few degrees. I ran it this way for 15 minutes. Then I added Ice cold water and let it sit for a while to "Chill down". The results were still good but noticably less once I added the water.

Conclusions:

The Idea works. In order to make it compete with the vortex, I will have to:

Increase the surface area of the individual pipes for better thermal exchange. This will make the pipes more like a radiator by flattening them into an oval (in the middle). Add even more (exchange) pipes to slow the fog speed down even more as it travels through the cooling chambers. This will also transfer a lot more thermal energy.

Make a (slightly) larger expansion chamber.

Improve the cooling chamber layout to resolve some minor thermal conflicts.

Check in to Greystone for a LONG rehab.

I'm not expecting ANYONE to try to build one of these. I'm doing it to satisfy my own curiousity. BUT if I can get it to work the way I envision, We'll have a viable alternative to the reverse vortex that uses a LOT less ice or Dry ice. It might also be usable indoors without the need for a tray to capture the melted Ice water.


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## corey872

Interesting design - will be neat to see how it works once it all comes together. I would only caution the dry ice and water isn't going to do much for you. 

Consider plain ice and water will cool to 32F, plain ice and salt water might get down to 26F. If you run dry ice and water, it will still only go down to 32F - if it goes lower, the water will freeze, expand, and possibly crack the chiller apart.

Ethanol would stay liquid all the way down to the -109F of dry ice, but that brings up a whole other set of issues such as compatibility with the foam/glue, being flammable, etc.

I would also mention, I've heard instances of people seeming to think the fog got 'too cold' and started to condense back out of the air. I suspect the ultimate goal may be to chill the fog just enough to achieve the desired effect, not chill it as much as absolutely possible.

Anyway, just my .02 - let us know how the additional experiments turn out.


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## niblique71

corey872 said:


> Interesting design - will be neat to see how it works once it all comes together. I would only caution the dry ice and water isn't going to do much for you.
> 
> Consider plain ice and water will cool to 32F, plain ice and salt water might get down to 26F. If you run dry ice and water, it will still only go down to 32F - if it goes lower, the water will freeze, expand, and possibly crack the chiller apart.
> 
> Ethanol would stay liquid all the way down to the -109F of dry ice, but that brings up a whole other set of issues such as compatibility with the foam/glue, being flammable, etc.
> 
> I would also mention, I've heard instances of people seeming to think the fog got 'too cold' and started to condense back out of the air. I suspect the ultimate goal may be to chill the fog just enough to achieve the desired effect, not chill it as much as absolutely possible.
> 
> Anyway, just my .02 - let us know how the additional experiments turn out.


I might not have been clear about the "Dry Ice chamber", It's designed to run with JUST dry ice, No water. I didn't have any Dry Ice to test it, so I used Ice and water in that chamber just to see if the concept was working. Before I make any modifications or change the design, I want to test it with about 2-3lbs of dry ice. The hopefull outcome is a chiller that will consume a LOT less cooling materials.

I doubt I will "overcool" the fog with this design, But if it did, than it'd be easy to adjust the cooling materials. I had that experiance last year when I used too much Dry ice in my reverse vortex. It actually froze the fog in the chamber and condensed it all around the Ice and formed a solid membrane. I found that 80-90% Ice and 10-20% dry ice really did the trick. More than anything it slowed the melting of the regular ice.


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## Vlad

lol, no just ribbing you Greg. It's crazy wild and I can't wait to see it in action.


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## Haunted Spider

Curiosity is killing me on this one. Are you going to tear apart your whole design and restart with bigger chambers? Also, if one were to decide to build this contraption, what is the approx cost. Just curious

And when pray tell are you posting a video?


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## niblique71

Spiderclimber said:


> Curiosity is killing me on this one. Are you going to tear apart your whole design and restart with bigger chambers? Also, if one were to decide to build this contraption, what is the approx cost. Just curious
> 
> And when pray tell are you posting a video?


I probably won't tear the first one apart. It showed a lot of promise during the first round of testing (with plain water ice). With Dry ice in the final chamber I think it will perform admirably. One test I can do without tearing the first one apart is to add that larger expansion chamber and enlargen the exit hole to 3".

I plan on building a second version that will incorporate a much larger expansion chamber, 4" inlet/outlet pipes, and more copper pipes in the "air" and "water/ice" chambers. In this version, the pipes will be 1/2" thinwall copper instead of 3/8"od. I'll "Flatten" the middle sections of them to get much better thermal exchange. I'll also add about 30% more of them to slow the fog down more and increase the thermal exchange even further. My goal is to have acceptable results with only 21lbs plain old water ice. By adding 2lbs or less of dry ice in the final chamber I should get results comparable to the vortex chillers which many haunters are already adding dry ice into. The Ultimate goal is to get the same results as the Large reverse vortex with 1/3rd the ice bill.

As far as a video?? If I'm liking the results, I'll post a video. It's just an experiment for now. I know it's going to be a tall order to successfully compete with the reverse vortex style chillers. But, what the heck, I'm enjoying the challenge.

I'm still reading the original (legendary) vortex thread, and I'm really enjoying it. There is SOOOO Much great information in there. It's almost painful to re-live all of the experiments that people did. I did all of the same ones, and came to similar conclusions (So far), almost 5 years later. Reading that thread FIRST would have saved me a LOT of time. Great Job to EVERYONE who participated.


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## SoCal Scare

Curious if you ever built the second chiller with the improvements?


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## jaege

You are a man on a mission.


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## angel3210

i have been reading all your chiller/s info on here in hopes of learning the best chiller to make (just wanted to say so far your info is one of the best out there on new ideas and sharing your thinking processes is very helpful in getting minds clicking) heres my questions for you to ponder,,,, ( my ideas) since copper (Thermal conductivity: 401 W m-1 K-1) is costly and pipe can be thick walled and aluminum (Thermal conductivity: 237 W m-1 K-1 ) is cheaper and thickness matters sometimes in heat exchange, so thin walled aluminum will transfer a temp fairly fast when in full contact dry ice(conductive transfer). what if you pumped cold saltwater(or used vodka? no dont drink it, pump that past dry ice most alcohols dont freese easy, .. 
(Freezing points of some common liquids in (Kelvin) lower the number= the better at not freezing solid
Fresh Water is 273(K) =31.7Fahrenheit
Sea/salt Water270.6 ,
Castor Oil 263.2 ,
Linseed oil 253 ,
Carbon Dioxide 194.5 (Dry ice solid/frozen form of carbon dioxide. used primarily as a cooling agent.) ,
Freon refrigerant R-11 162 ,
***Alcohol, ethyl (ethanol) 158.6 ,
Freon refrigerant R-12 115 

Thermal Conductivity( differance in temp tranfers vs freeze also matters)
FreshWater 0.609 great conductivity ,
Castor Oil 0.180 ,
Linseed oil ? ,
Alcohol, ethyl (ethanol) 0.171 ,
Freon refrigerant R-11 0.093 ,
Freon refrigerant R-12 0.071 
(so maybe another good use for absolute vodka besides saving poisoned dogs that drank anti freeze might also work for chiller? its freezes below dry ice temp and has a fairly ok conductivity - remember all consumable high percent alcohol still has water in it so will flow slushy, pond pumps might work but an icecream moter running the dasher might stir and help with both conductive and convection heat/cold transfer better. you could almost make a closed unit with copper piping containing alcohol just like a reverse of a oil radiator heater you heat oil that radiates heat to room air) 
then run copper pipes that were centered in the middle of larger aluminum(cans) pipes that the fog flows , that aluminum is then surounded by dry ice or reg ice also. you could even use your house freezer to keep refreezing the vodka to slush this might cool the fog down and help with not having to use as much reg water ice? not sure i wrote this very well in explaining my idea but maybe you can get a few ideas.


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## niblique71

SoCal Scare said:


> Curious if you ever built the second chiller with the improvements?


I really wanted to. I'm self employed in a luxury business and very few spent money on luxury this year. I had No money to experiment on my fog chiller concepts. Prices for Copper and other thermal metals are outragious right now.
I was going to put the existing new (Now old) chiller through it's paces this year but the fall storm totally messed up any opportunity. It Paralized my setup a week before it's arrival.

Doing calculations after my last post I realized that I need a lot more "Area" on the copper tubing. I'd need to double (or more) the amount of "Passage" by using bigger pipes (Flattened) or just more smaller pipes. I also learned that direct fog contact to the melting Ice does help with chilled fog thickness and overall quality. Since this particular design has no direct contact with melting icewater, there would be some loss there.\

However, I belive the design still has merit based on my initial tests. There are professional fog chillers that are used in movies all of the time and I doubt they would use melting Ice with Electrical lighting all around and million dollar actors/actresses on set. ZZZZZZZTTTZTZTZTZTTZZTTZTZTZZTZ

Anyway, I still want to do an improved model if my funds can handle it. AND do a complete test with the existing model. let the Halloween Gods provide good economic circumstances and great weather this comming year. THis project is NOT dead... It's Just sleeping.



> i have been reading all your chiller/s info on here in hopes of learning the best chiller to make (just wanted to say so far your info is one of the best out there on new ideas and sharing your thinking processes is very helpful in getting minds clicking) heres my questions for you to ponder,,,, ( my ideas) since copper (Thermal conductivity: 401 W m-1 K-1) is costly and pipe can be thick walled and aluminum (Thermal conductivity: 237 W m-1 K-1 ) is cheaper and thickness matters sometimes in heat exchange, so thin walled aluminum will transfer a temp fairly fast when in full contact dry ice(conductive transfer). what if you pumped cold saltwater(or used vodka? no dont drink it, pump that past dry ice most alcohols dont freese easy, ..
> (Freezing points of some common liquids in (Kelvin) lower the number= the better at not freezing solid
> Fresh Water is 273(K) =31.7Fahrenheit
> Sea/salt Water270.6 ,
> Castor Oil 263.2 ,
> Linseed oil 253 ,
> Carbon Dioxide 194.5 (Dry ice solid/frozen form of carbon dioxide. used primarily as a cooling agent.) ,
> Freon refrigerant R-11 162 ,
> ***Alcohol, ethyl (ethanol) 158.6 ,
> Freon refrigerant R-12 115
> 
> Thermal Conductivity( differance in temp tranfers vs freeze also matters)
> FreshWater 0.609 great conductivity ,
> Castor Oil 0.180 ,
> Linseed oil ? ,
> Alcohol, ethyl (ethanol) 0.171 ,
> Freon refrigerant R-11 0.093 ,
> Freon refrigerant R-12 0.071
> (so maybe another good use for absolute vodka besides saving poisoned dogs that drank anti freeze might also work for chiller? its freezes below dry ice temp and has a fairly ok conductivity - remember all consumable high percent alcohol still has water in it so will flow slushy, pond pumps might work but an icecream moter running the dasher might stir and help with both conductive and convection heat/cold transfer better. you could almost make a closed unit with copper piping containing alcohol just like a reverse of a oil radiator heater you heat oil that radiates heat to room air)
> then run copper pipes that were centered in the middle of larger aluminum(cans) pipes that the fog flows , that aluminum is then surounded by dry ice or reg ice also. you could even use your house freezer to keep refreezing the vodka to slush this might cool the fog down and help with not having to use as much reg water ice? not sure i wrote this very well in explaining my idea but maybe you can get a few ideas.


Wow I just read this tonight... Ummm Gotta get Zurg to help me digest this. You are way more informed about caloric values than I am my friend. but I probably could use your help to make a professional model that IS AFFORDABLE


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## niblique71

I thought I'd revive this thread just because I plan on buying some dry ice again this year. I never did get to test it in the environment that it was designed for with 4 separated chambers. 
Chamber #1 is the expansion/collection chamber
Chamber #2 is air cooling with the copper tubes (Fan assist)
Chamber #3 is Ice/Water cooling (Copper tubing)
Chamber #4 is Dry Ice (only) Cooling through copper tubes

I halted experiments when the economy went bad and copper shot through the roof. I remember having very satisfactory results with just water ice and hope to revive this chller design and it's prototyping.

The goal isn't to make better chilled fog. but rather to make the same good chilled fog with less Ice ($$) for a longer duration between ice refills.

If nothing else??? It's Interesting....


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## Offwhiteknight

Looking forward to reading about it. Always fascinating.


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## MommaMoose

I love reading these threads on the fog chillers. Granted some of it reads like Latin to me but the more I read the more I begin to understand. Seeing all the testing that went into the Reverse Vortex Chiller has given me the courage to build one myself. Granted it won't be as elaborate as yours but I am gonna do it. Thanks so much.


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## mrdonl

Have you thought about recirculating the ice water through some of the copper pipes?


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## [email protected]

This chiller will win the top prize in the complexity category for sure.


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## typoagain

You do know the make meds to help with you obsession?

LOL! I love it! This is how hobbyist can actually drive an industry! I really like the concept and can see why you are doing it this way. I love the way you think!

But I have to ask, why not just buy a 110V cooling system like you would use in a coke machine and pump the fog through the cooling coil? Very little condensation, you can place the system in another room if noise was a concern, and you would never have to buy ice again.


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## niblique71

MommaMoose said:


> I love reading these threads on the fog chillers. Granted some of it reads like Latin to me but the more I read the more I begin to understand. Seeing all the testing that went into the Reverse Vortex Chiller has given me the courage to build one myself. Granted it won't be as elaborate as yours but I am gonna do it. Thanks so much.


Your welcome. I really just had a thought in my head about how to make a non-ice contact cliller and wanted to see if it would work. Mainly because melted icewater is still cold and still has negative caloric value.

After my initial tests with this prototype, Lunatic and I have sorta agreed that direct contact with ice can improve the quality of the fog through "Transpiration". Ice melting within in hot fog creates a cooling effect over and above the caloric valfue of the ice. It's much the same concept as sweat evaporating to cool us when it changes states from a liquid to a gas. Changing from a solid to a liquid does much the same thing and actually cools the fog more than the initial caloric value of the ice.

Plus we suspect that some cool water vapor is added to the fog improving it's density.

All of this information...... and I still want to try this chiller.... LOL I believe it will work but I might need another prototype with a few improvements.



mrdonl said:


> Have you thought about recirculating the ice water through some of the copper pipes?


Yes, I did think of recirculating the icewater into the first chamber after I designed this prototype. there's no way to retrofit this one. If I have a decent winter (Financially), I might try to build a better mousetrap with some improvements.



[email protected] said:


> This chiller will win the top prize in the complexity category for sure.


 ROfLOL, Ummm Yes, I know that it's overkill. I should have named the thread the "Rediculous Rube Goldberg Chiller". But it's a concept that I just HAD to try.



typoagain said:


> You do know they make meds to help with you obsession?
> 
> Ridlin??
> 
> 
> LOL! I love it! This is how hobbyist can actually drive an industry! I really like the concept and can see why you are doing it this way. I love the way you think!
> 
> But I have to ask, why not just buy a 110V cooling system like you would use in a coke machine and pump the fog through the cooling coil? Very little condensation, you can place the system in another room if noise was a concern, and you would never have to buy ice again.


The problem (I think) with using a standard refridgerator type chilling system, is that it is designed to cool food items in a very insulated chamber over the course of many hours. The refridgerator also relys on existing food or beverages that have already been chilled, or frozen. Hot fog would most likely overwhelm a standard refridgerator if empty. However, a freezer pre loaded with lots of ice might keep up and deserves some consideration. I think You would need those existing negative calories (Ice) for a standard freezer to keep up with a night of heavy fog. Plus you'd still need a lot of surface area to transfer the cold that an icematrix would provide.

Hey it could work and the principal is sound. It's all experimentation. Someone will eventually have the guts to successfully hack a fridge for this purpose. It may have already been done.

Right now The only thing electrical in this 4 chamber design would be an optional computer fan. I have ideas to eliminate that as well in future designs if the principals seem to work.


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