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-   -   TMIC Evaporator coil (http://legacygt.com/forums/showthread.php?t=163647)

rad.rac3r 06-07-2011 06:27 PM

TMIC Evaporator coil
 
1 Attachment(s)
Im not sure if there are any other HVAC guys on the forum but i had this idea the other day on a roof of a building while i was working...maybe it was the sun cooking my brain:spin:...but... To make it simple, your condensing unit outside does exactly what its called; it condenses refrigerant thats in a vapor form, to liquid. To do so it has to take away heat; the more heat it takes away, the better. On the evaporator side (usually if not always in your airhandler), it does the total opposite. Right before that is a metering device which takes the liquid (that was condensed at...the condensor:rolleyes:), and only lets out a certain amount (kind-of like a fuel injector, turning it into a mist/vapor). At 15.25 PSI, the most commonly used refrigerant r22, has a boiling point of..-40; so this vapor is now sent through the evaporator where your air-handler, containing a fan, heats up the refrigerant (which in turn is where you get all that cold air from), and turns it back into a gas for the compressor to bring the pressure up again for the condenser.

okay after that HVAC-101 lesson, heres my idea...

It would basically be the same rig, but where the evaporator would be, the TMIC. the amount of heat thats created from the engine alone would heat it up enough to keep the cycle going, and in turn chill the air going to the turbo. I have the idea for everything drawn out (horribly..see attached), but the only place where i ran into a roadblock is in regards to the TMIC..how could i possibly get it so that copper lines would be able to gather enough heat from the air traveling through? One idea i had was to mount a thin enough coil over the TMIC (which is a coil basically), and an electric fan above that. To control it all and have it somewhat automated, a thermostat mounted in the outlet of the IC that would close a normally open switch, energize a contactor, which would in turn power the compressor, and step down the voltage for the electric fan; when its satisfied, it would shut off on its own; on a time delay to avoid cycling. For the lines running in between everything, instead of using copper, there are flexible lines that i can use that will never leak and also will make it easier to mount the whole thing, the only copper would be at the evaporator/TMIC, condensor, and compressor.

So, any ideas on how pipe, copper lines through the fins of the IC so that its cools the whole block?

**excuse the very crude drawing..:lol:**

sumfoo1 06-07-2011 07:32 PM

i would use an air to water intercooler core and decompress the r22 into the "water" side and have the air still run through the air side...

the compressor running will negate most of your hp gain but if you could accumulate cold, compressed refrigerant and then release it during boost it would defiantly make power.

p.s. i'm an hvac designer/commissioning agent

SBT 06-07-2011 07:38 PM

Quote:

Originally Posted by sumfoo1 (Post 3420002)
i would use an air to water intercooler core and decompress the r22 into the "water" side and have the air still run through the air side...

Interesting, hadn't thought about this approach.

Rather than running the A/C compressor side off the engine, where it's completely parasitic, how about using one of the small Hybrid/Electric car A/C units that run off the battery. Then it could truly be an on-demand system independent of the vehicle's cabin A/C.

mwiener2 06-07-2011 08:10 PM

I've thought about an idea like this before. Use a water/air IC and instead of water, use refrigerant. You run the compressor while staging and basically freeze the IC, then when the light turns green the compressor turns off and you should have enough thermal mass to keep the IC cold through the run.

sumfoo1 06-07-2011 08:14 PM

Yeah you could use an accumulator too.

rad.rac3r 06-07-2011 08:42 PM

1 Attachment(s)
Quote:

Originally Posted by sumfoo1 (Post 3420002)
i would use an air to water intercooler core and decompress the r22 into the "water" side and have the air still run through the air side...

the compressor running will negate most of your hp gain but if you could accumulate cold, compressed refrigerant and then release it during boost it would defiantly make power.

p.s. i'm an hvac designer/commissioning agent

Awesome, an engineer. Mind if i pick your brain a little?

Maybe you could elaborate a little more on how the compressor would negate the HP gain? I guess i left out also having a spare battery in the back. This whole system would be separate from the care entirely; short of the thermostat. Re-reading what you said does make sense though..but "releasing" it during boost, where would you store that evaporated refrigerant.

In regards to the air to water intercooler, im not very familiar with those systems, so how does that come into play?

Quote:

Originally Posted by SBT (Post 3420009)
Interesting, hadn't thought about this approach.

Rather than running the A/C compressor side off the engine, where it's completely parasitic, how about using one of the small Hybrid/Electric car A/C units that run off the battery. Then it could truly be an on-demand system independent of the vehicle's cabin A/C.

Not running of the engines compressor, but having something stand-alone. So yes, like the battery powered A/C units, and still on demand based on outlet temp. Although, im not at all familiar with a/c units in cars.

for example: http://cgi.ebay.com/Masterflux-48-vo...item3cb3cefbe4

ViscousSquirrel 06-08-2011 01:04 AM

I believe ford has done and patented something similar

http://www.fordforums.com/f474/svts-...plained-33176/

ssbtech 06-08-2011 01:19 AM

All I want is for the A/C to cool the cabin properly :mad: To hell with the IC :p

BAC5.2 06-08-2011 02:34 AM

1) Cars now use R134-a, not R22 or R12 anymore.

2) It's not a new idea to use the A/C system to supplement cooling. Having an independent A/C system just for the intercooler is going to be awfully heavy, but people have definitely sacrificed their cabin A/C to cool their intercoolers.

That said, at full-bore, an A/C compressor consumes a lot of power. Most cars, at WOT, shut off the compressor (in slow cars, you can feel the air begin to blow warm on long WOT pulls).

Is it worth the trouble? It'll keep heatsoak at bay, but it would provide for a very inconsistent operating temperature (especially if the compressor shuts down at WOT).

I'd consider a well designed AWIC before I invested too heavily into something like this. After all, I'd rather my A/C keep my cabin cool.

sumfoo1 06-08-2011 04:47 AM

I agree with everything bac said

And just an FYI I in no way shape or form have done any calculations or give any form of approval that this setup will work.

But it would be a neat experiment.

The last f150 lightning concept had a way to dump the accumulator into the intercooler and it would give an extra 20-30hp for 10seconds. I'm pretty sure they used something similar to a standard type evaporator coil in the intake just past the air to water intercooler.

ShadowImg 06-08-2011 05:05 AM

Probably more effective in the end to just use an IC sprayer, water injection, and/or packing the intercooler with ice.

For the first two, the storage tanks are usually not in the engine bay and much much cooler consistently.

rad.rac3r 06-08-2011 06:38 AM

Quote:

Originally Posted by BAC5.2 (Post 3420339)
1) Cars now use R134-a, not R22 or R12 anymore.

2) It's not a new idea to use the A/C system to supplement cooling. Having an independent A/C system just for the intercooler is going to be awfully heavy, but people have definitely sacrificed their cabin A/C to cool their intercoolers.

That said, at full-bore, an A/C compressor consumes a lot of power. Most cars, at WOT, shut off the compressor (in slow cars, you can feel the air begin to blow warm on long WOT pulls).

Is it worth the trouble? It'll keep heatsoak at bay, but it would provide for a very inconsistent operating temperature (especially if the compressor shuts down at WOT).

I'd consider a well designed AWIC before I invested too heavily into something like this. After all, I'd rather my A/C keep my cabin cool.

1) The idea wasent to use the cars a/c, but to have a separate system.

2) None of it would run off of the cars engine. So theres no way and/or reason for the car to shut off the compressor.

In regards to weight, I dont need a big compressor to run this because im not trying to freeze or cool down a room; just enough to keep the IC's temp within a certain range. The compressor that i posted above is 14lbs, 40lbs for the spare battery. A grand, rough total of 54 lbs in the back of the car. I doubt that'd do much to hurt performance..think of the things most people lug around in their car, let alone themselves :lol: rubber hose instead of copper lines shaves some weight aswell. Only part that im not sure of would be the evaporator.

Right before the evaporator is the expansion valve/metering device, its adjustments are all regulated by a bulb placed after the evaporator. If it senses that the temp is to high or too low, it makes its own adjustments accordingly. Thats how your evaporator in your home keeps the temp that you set relatively consistent.

Quote:

Originally Posted by sumfoo1 (Post 3420368)
I agree with everything bac said

And just an FYI I in no way shape or form have done any calculations or give any form of approval that this setup will work.

Eh any idea has to come from somewhere; never knew calculations to come before ideas :icon_tong

GTTuner 06-08-2011 07:16 AM

Why not just get a CO2 I/C sprayer? You don't need 40 degree charge temps all the time. The only way this would be beneficial would be if the compressor is not driven off th engine. Nice idea though, I had thought once of directing the interior AC duct work into the air cleaner.

BAC5.2 06-08-2011 07:22 AM

54 pounds, plus R134, plus evaporator, plus hoses, plus mounting brackets, plus whatever the core weighs. You are looking at 100 pounds of stuff. I agree, it's not a huge deal for a non-race car. But it is the weight difference of an automatic versus manual transmission.

The car shuts off the stock compressor anyway. The added compressor will put a strain on the alternator, so that's something to consider. If you increase electrical load, you increase the power consumption of the alternator.

The intake flow rate is pretty high, more than a third of a kilo per second at WOT in high power conditions. You need a high efficiency, high output system to be able to sufficiently cool flow like that. You can suffer a low efficiency system, when time is a luxury. In this case, it's not.

When you are attempting to cool rapidly moving air, you need to have a much colder exchanger. An accumulator, like Sumfoo1 mentioned, is your best bet for "blast chilling" the intake air.

You are talking about a system that will "super cool" your intake. Since you have transient lag between changes in temperature with any HVAC system, doubly impacted by a variable cooling load requirement, the bulb-feedback system is going to be inadequate for sufficiently controlling temperatures with any degree of accuracy. Your house doesn't go from 70 degrees to 100 degrees in tenths of a second.

I haven't, and I probably wont, do any calculations to progress this idea. SumFoo1 would be a better source for that, since HVAC is what he does.

As an engineer, I would invest my time in developing a properly designed AWIC. From that, you could have a small compressor running cooling pipes through the storage tank, to regulate the water mass temperature. If you want to design a "race" mode, I'd run a 20lb CO2 or Nitrous bottle, with charge pipes through the storage tank. The vented gas could be used to cool the exchanger up front (or maybe strap a kazoo to the end, so people will know you are serious).

sumfoo1 06-08-2011 08:32 AM

yeah... the only thing that makes me think it could work is that refrigerant cycles transfer more energy than they consume.

I would tap into the stock system, create a 2gal high pressure tank (post condenser) and bleed that off into your evap coil while the compressor isn't running this would reduce pressure and if you don't have the system energized allow your stock a/c to stay cold when the clutch disengages.

It probably won't be worth it... but then again... if you can drop the charge to 35 degrees for 20 seconds... that's a lot of HP that could be picked up... We're talking near e85 power on pump.

Again... i may be a designer for this stuff but I'm not doing the math for it and do not want any liability in it.

If you're looking for controls on a DX setup like that you'd need to talk to someone who designs the Internal AHU contols... i just make sure they work.

The assisting an air to water system would be an easier thing to control but if for whatever reason you ruptured a line and dumped gallons of low temp water on a hot engine that would be bad too... and talking about weight... air to water systems are HEAVY because they have water in them.

I'm going tmic and e85 because the evaporative cooling of e85 before (and during) combustion will be more effective than a setup like this could be.


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