Turbo's and air density.

RonA said:
So it needs to be rated for a bit more flow like this one?

Water to Air Intercoolers

RonA

By the way, my hat is off to you for being able to run it as a single. I had to take a half day off after holding it in place and getting the bolts started.[/QUOTE


You may get away with the 2000hp unit if you keep the boost down. At 65psi we are seeing a large drop in pressure. I think in the end the 3000hp you listed will suit your needs better. I just had a custom a/w made with Garrett cores, I am still shaking my head at the differance in power over the 2000hp frozen boost unit with just a little gt4718r lol. Keep in mind it was almost 5 times the price though:nail: So it would depend on how serious you are about making every last hp. I will post a vid of Randys truck as soon as I have video! She sounds nasty at 5000rpm and 65psi:bow:
Click to expand...
 
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RonA said:
So it needs to be rated for a bit more flow like this one?

Water to Air Intercoolers

RonA

By the way, my hat is off to you for being able to run it as a single. I had to take a half day off after holding it in place and getting the bolts started.
Click to expand...

I run that w/a instead of an air to air on my truck Ron. It's holding up at 90psi so far. I know that won't matter just for your primary though. I have 4" pipe to it and 3.5 after the cooler. And it spools very fast. The efficiency of the W/A is awesome. I've got an all aluminum afco dragster radiator for it with an 8 gallon fuel cell and a Bosch pump in the bed. That cooler holds a gallon of water and weighs 40lbs full of water, do it requires a pretty stout mount. I think it'll work awesome, but requires a lot of room.
 
RonA said:
I'm looking at putting a water to air cooler between stages. Looking at an air density chart and assuming 40psi out of a primary charger(ballpark), I see that 1 cubic ft of air at 40psi and 100 degreeF weighs .264 lbs. At 200 deg it weighs .244lbs and at 300 deg it weighs .195 lbs. That makes an 8% difference going from 100deg to 200 deg and a 35% difference going from 100 deg to 300deg. I have never checked temperatures after either turbo but was told to expect 300 deg + after the primary, and 450 after the secondary. How does the density of the air change the flow through the compressor? Will the secondary move more lbs per minute with the higher density air and if so is it directly related to the density going in. Basicly I'm asking if dropping the air temperature between stages from 300 deg F to 100deg F will increase the amount of air exiting the seconday charger by 35%?
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It is actually the opposite. Changes in air density via temperature are more sensitive at low temp versus high temp.

More dense air takes less energy to compress. Compressing gases actually takes much much more energy than compressing liquids. Anything you do to increase density will requires less shaft hp and thus less drive pressure. I think for a competition vehicle air to water intercoolers are a great choice, due to liquid being able to accept heat much more than air.

What are you considering for the cooling system? Ice water, stand alone closed loop water system with separate radiator, or engines radiator? Obviously efficiency drops as I listed those ideas accordingly. For low psi, plumbing into the engines radiator would probably be more of a detriment than benefit.
 
Not sure how compressing liquids takes less energy then gas as well?

images



Here's a couple of charts, of interest....make's it a little easier to visualize.
A cube of air at 100lbs boost and 500 degree's has a weight of .323
A cube of air at 50lbs boost and 80 degree's has a weight of .324


0-100.jpg


120-1000.jpg
 
Ron all you need to know is PV=nRT (the ideal gas law). I think you already knew this though based on some of your other calculations.

P=Pressure
V=Volume
n=Number of moles of a gas
R=Is a constant
and T=Temp in degrees Kelvin

A charger will typically move the same volume of air at a certain rpm. If you cool the air you'll make it more dense and therefore the number of moles of Oxygen will increase at the same volume. The weight of that air volume will also increase (because you've shoved more molecules into a smaller space) thereby increasing your drive pressure.

Now this is based on the ideal gas law that isn't perfect. You're probably more interested in statistical mechanics and the kinetic theory where n = N/NA is the number of moles of gas and R = NAkB is the gas constant. This takes in account the different elasticities of the air mixture. The problem is you can't contol the air mixture, only the temp, PSI and volume using turbo charging and intercooling. So, bottom line stick with PV=nRT.

The one issue with intercooling between stages is the amount of molecules of air is limited by the the amount coming from the first stage. No matter how dense you make it the number of moles of oxygen will be the same. You'd be much better off pre-cooling before it hits your first charger and after your last. This will ensure you get the most moles into the system and allow the greatest expantion prior to burning it.

Intercooling it between stages will allow the secondary charger to be smaller to flow the same amount of moles of oxygen.
 
I have a perfect spot to put this so the plumbing will be a snap. I'll take some measurements this afternoon and call a couple of the places that were recommended. Sounds like having a custom one made by a shop that is familiar with them may net the best results. I'd be all ears if someone knows of a shop that specializes in this sort of thing. Pretty is my last concern.
 
CurtisEmery said:
RonA said:
So it needs to be rated for a bit more flow like this one?

Water to Air Intercoolers

RonA

By the way, my hat is off to you for being able to run it as a single. I had to take a half day off after holding it in place and getting the bolts started.[/QUOTE


You may get away with the 2000hp unit if you keep the boost down. At 65psi we are seeing a large drop in pressure. I think in the end the 3000hp you listed will suit your needs better. I just had a custom a/w made with Garrett cores, I am still shaking my head at the differance in power over the 2000hp frozen boost unit with just a little gt4718r lol. Keep in mind it was almost 5 times the price though:nail: So it would depend on how serious you are about making every last hp. I will post a vid of Randys truck as soon as I have video! She sounds nasty at 5000rpm and 65psi:bow:
Click to expand...

Do you have temp probes before and after that new cooler? if so would you mind sharing your findings?
Click to expand...
 
I wish I did so I could give you guys some good solid proof. Hopefully next seasons budget will allow for a data logger so I can see the whole picture. Rpm, pre and post boost, pre and post charge temp, drive psi, water temp, 8 egt's, oil pressure, and the list goes on and on lol!
 
Give the guys at bell intercooler a call, they will get you setup with a custom unit that will fit your truck the best. It may cost more, but the cores they use are very efficient compared to the frozen boost cores, meaning more cooling in a smaller package
 
takedown95 said:
This is so completely wrong.

Try taking all the fluid out of your brake lines and just leaving the air.
Click to expand...

I can see what he's saying, although the compression of liquids may be the wrong term. If you were to compress both a liquid and a gas to 50% of the original volume, it would take exponentially more energy to compress the liquid.

If you are more concerned about pressurizing the fluids, the volume of the liquid would remain virtually unchanged. To pressurize a gas to 100 psig, you'd have to reduce the volume by 7.8 times. Or conversely, add 7.8 times more gas to the existing volume.
 
So with a greater density entering the secondary would overall boost drop yet still have the same amount of O2 in the charge?

Sent with a Droid RAZR in one hand and 14,000 volts in the other.
 
x2 on Bell Turbo. Erick Brown had one on his 1,138rwhp common rail between stages, and was only at 70-75psi. Not quite as cool as your power numbers Ron, but then again, it was a few years ago.
 
CurtisEmery said:
is it even scientificly possible to compress a liquid that much?
Click to expand...

[ame="http://en.wikipedia.org/wiki/Schwarzschild_radius"]Schwarzschild radius - Wikipedia, the free encyclopedia[/ame]

Read the parameters section.

RonA
 
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Cummin_un_glued said:
So with a greater density entering the secondary would overall boost drop yet still have the same amount of O2 in the charge?

Sent with a Droid RAZR in one hand and 14,000 volts in the other.
Click to expand...

takedown95 said:
Ron all you need to know is PV=nRT (the ideal gas law). I think you already knew this though based on some of your other calculations.

P=Pressure
V=Volume
n=Number of moles of a gas
R=Is a constant
and T=Temp in degrees Kelvin

A charger will typically move the same volume of air at a certain rpm. If you cool the air you'll make it more dense and therefore the number of moles of Oxygen will increase at the same volume. The weight of that air volume will also increase (because you've shoved more molecules into a smaller space) thereby increasing your drive pressure.

Now this is based on the ideal gas law that isn't perfect. You're probably more interested in statistical mechanics and the kinetic theory where n = N/NA is the number of moles of gas and R = NAkB is the gas constant. This takes in account the different elasticities of the air mixture. The problem is you can't contol the air mixture, only the temp, PSI and volume using turbo charging and intercooling. So, bottom line stick with PV=nRT.

The one issue with intercooling between stages is the amount of molecules of air is limited by the the amount coming from the first stage. No matter how dense you make it the number of moles of oxygen will be the same. You'd be much better off pre-cooling before it hits your first charger and after your last. This will ensure you get the most moles into the system and allow the greatest expantion prior to burning it.

Intercooling it between stages will allow the secondary charger to be smaller to flow the same amount of moles of oxygen.
Click to expand...


I'd put some more thought into that. Ron will be way further ahead cooling the high density charge from the primary.



^^ Damnit Ron that page gave me a big ol headake.
 
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Yep. My son is really into physics. For a dad that didn't do well in algebra, it's a bit embarrassing get caught up in some of the conversations.
 
Joesixpack said:
I'd put some more thought into that. Ron will be way further ahead cooling the high density charge from the primary.
Click to expand...

I can see where cooling the air from the primary could allow more air to be fed into the secondary since the PSI to get the same volume of air into the secondary would be reduced. By reducing that resistance the primary charger has to "work" less and could flow a larger volume of air.

Is this the theory you're proposing?
 
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