Time to go Stage II!

[Mike E]

I think using nitrous in your intercooler sounds like a much better idea that adding another co2 tank. But, you should do some math to figure out what mass flow rate of nitrous you would need to provide the cooling. If I have time today I'll see if I can find an equation, but I'm thinking it would take a really high flow rate. That's why water works so well, the mass flow rate is usually incredibly high. Same with an air to air at 100mph+.

 

[Mike E]

I'm pretty sure in simplest form this equation will work for you.

M1(Cp1)(Delta T1) = M2 (Cp2)(Delta T2)

There should be a factor in there on the M2 side to account for heat transfer effeciency of the fins. But this will get you a ball park mass flow rate.

M1 is Mass flow rate of the air side in lb/hr (should be able to get this from the compressor map)
CP1 is specific heat of air in BTU/lb *F = .24 for air
Delta T1 is your desired temp drop on the air side in *C

M2 is mass flow rate for nitrous. What you want to solve for.
CP2 for nitrous is .21
Delta T2 at best for nitrous is the boiling point to atmospheric temperature. -127F + 70 = 197F You would probably have to play with the outlet size on the intercooler "water side" to to maximize this number.

M2= M1 (Cp1 * Delta T1)/(CP2 * Delta T2)

M2 = M1* 1.14 (Delta T1/ 197)

 

[Alky V6]

I'm pretty sure in simplest form this equation will work for you.

M1(Cp1)(Delta T1) = M2 (Cp2)(Delta T2)

There should be a factor in there on the M2 side to account for heat transfer effeciency of the fins. But this will get you a ball park mass flow rate.

M1 is Mass flow rate of the air side in lb/hr (should be able to get this from the compressor map)
CP1 is specific heat of air in BTU/lb *F = .24 for air
Delta T1 is your desired temp drop on the air side in *C

M2 is mass flow rate for nitrous. What you want to solve for.
CP2 for nitrous is .21
Delta T2 at best for nitrous is the boiling point to atmospheric temperature. -127F + 70 = 197F You would probably have to play with the outlet size on the intercooler "water side" to to maximize this number.

M2= M1 (Cp1 * Delta T1)/(CP2 * Delta T2)

M2 = M1* 1.14 (Delta T1/ 197)

Good stuff, Mike. Thanks.
On the Delta T2, where you have -127F + 70 = 197F, shouldn't that be -127F + 70 = -57F ?
Then, M2 = M1 * 1.14 (Delta T1 / -57) ?

 

[Mike E]

Good stuff, Mike. Thanks.
On the Delta T2, where you have -127F + 70 = 197F, shouldn't that be -127F + 70 = -57F ?
Then, M2 = M1 * 1.14 (Delta T1 / -57) ?

No it's difference in temperature. The difference between -127 and +70 is 197. I didn't mean for it to be an equation. But properly it should be -127 - 70 = -197 . positive or negative doesn't matter it will just give you a negative flow rate.

I did some quick math. If you use 150lb/min of air from the turbo and you want to cool it 200 degrees in the cooler. M2 is 171 lb/min. With a 15 lb. bottle assuming you can keep constant flow from the bottle (which you can't), you would empty it in 5 seconds. That's a lot of nitrous.

 

[turbobitt]

What if instead of using water as the cooling medium with a liquid intercooler, I used nitrous oxide? I will have nitrous onboard already, and I will be using the nitrous for spooling purposes, as I've done in the past. Then, after the turbo has reached the target boost level and the nitrous to the engine has been shut off, the nitrous could be diverted to the intercooler.
After the intercooler the gas could then be run to a small air to air intercooler in the plumbing between the air cleaner and turbo compressor. The nitrous would be used twice before being expelled to the atmosphere.
What if instead of expelling the nitrous randomly into the atmosphere, it was expelled into a small half-shield surrounding the intake air filter? The nitrous would be used twice over through two intercoolers, then partially consumed by the engine instead of just being wasted overboard.
What about running the nitrous system purge into the liquid style intercooler to reduce intercooler temps in preparation for the run before staging?

Just thinking out loud but I would be concerned that the NO2 would pick up heat inconsistantly and change the flow characteristics and make it a moving target to tune.
Allan G.

 

[Alky V6]

Just thinking out loud but I would be concerned that the NO2 would pick up heat inconsistantly and change the flow characteristics and make it a moving target to tune.
Allan G.

I think that is more of a problem when trying to maintain a constant a/f ratio through the engine, but for simply cooling an intercooler, I don't see it as being that critical.

 

[Alky V6]

No it's difference in temperature. The difference between -127 and +70 is 197. I didn't mean for it to be an equation. But properly it should be -127 - 70 = -197 . positive or negative doesn't matter it will just give you a negative flow rate.

I did some quick math. If you use 150lb/min of air from the turbo and you want to cool it 200 degrees in the cooler. M2 is 171 lb/min. With a 15 lb. bottle assuming you can keep constant flow from the bottle (which you can't), you would empty it in 5 seconds. That's a lot of nitrous.

Interesting. I think I'm going to give this a try. I'll start out with a lower flow rate with the nitrous and take measurements, work from there. Maybe the equivalent flow rate of a 200 shot. 4 nozzles spaced equally shooting at the core. It's got to be better than what I was doing lately, running the intercooler dry.

 

[turbobitt]

I think that is more of a problem when trying to maintain a constant a/f ratio through the engine, but for simply cooling an intercooler, I don't see it as being that critical.

OK, I thought you were refering to plubing through the intercooler before injecting into the engine. Sounded like a tuning nightmare.
Allan G.

 

[HelloBozos]

Cool Build!!, being a total smartarse i am,If the car's ever down, you could rent out that turbine on the front to drain Lakes in search an rescue missions...heheh. Keep-up the the awsome build!

 

[Alky V6]

What do you think of this idea?

 

[Alky V6]

The wastegate is finally mounted! Yay!

 

[Alky V6]

More views.

 

[Squid4life]

Very cool. Love the position. Donnie, your Tig welds are looking just like the machine ones on the collectors. Very nice.

 

[Alky V6]

Very cool. Love the position. Donnie, your Tig welds are looking just like the machine ones on the collectors. Very nice.

Like the machine welds. Yeah, right. You're pulling my leg.

 

[Alky V6]

I almost forgot. I still need to weld in the bungs that will be used for the afterburner nitrous injection nozzle, and an EGT probe.

 

[kidglok]

looks beautiful donnie. Now it looks like the exhaust has to make a 90* angle to go through the wastegate, im sure you thought about that, but whats to say it wont flow passed the wastegate directly to the turbo?

 

[RIFF RAFF]

Cool Build!!, being a total smartarse i am,If the car's ever down, you could rent out that turbine on the front to drain Lakes in search an rescue missions...heheh. Keep-up the the awsome build!

I BET HIS CAR RUNS WHEN HE'S DONE .

 

[HelloBozos]

I BET HIS CAR RUNS WHEN HE'S DONE .

You never know, new builds mean new bugs, I sure hope it does.Love to hear it at full boost!!!

 

[Alky V6]

looks beautiful donnie. Now it looks like the exhaust has to make a 90* angle to go through the wastegate, im sure you thought about that, but whats to say it wont flow passed the wastegate directly to the turbo?

You've got me curious. Where do you see the 90 deg angle? The old Stage I setup was 90 degrees. I don't see it on this one. Please enlighten me.
This new wastegate plumbing is more favorable compared to the old Stage I setup, and the way this wastegate controlled boost with the old setup, where the flow did have to make a 90 degree turn, was without a hitch. If anything this new mounting should be an improvement, but I really doubt I'll be able to notice the difference. I just thought this way of plumbing it made more sense from a flow perspective.

 

[Alky V6]

So, what did you think of my mini NACA ducts?