Turbo's and air density.

Its funny to see this topic come up because i have been kicking the same idea around for months , lack of space on a dmax between stages has made me decide to go the route of using small amounts of nitrous to hopefully achieve a similar result , the goal will be to spray at the inlet of the atmosphere stage , and again in the charge pipe between stages , and pre inter cooler as well , starting with very small jets , just enough for cooling . If that doesnt work then a W/A between stages will be in order .
 
^^ I was actually just thinking about something like this, A small shot between stages and a big shot preintercooler.
 
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.
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Yes that is the idea, removing the thermo energy which reduces the volume of the gas per unit of oxygen if you think of it like that. The main benefit I see from this is being able to run a smaller secondary (and be able to spool it easer) and running cooler temps in the compressor. You are not going to get any more air into the system, that is determined by how much your primary is flowing (assuming no big restrictions from the secondary)
You also get the benefit of a cooler charge overall
 
I believe the secondary is a restriction and it seems like this would be a good way to allow it to more effectively move the air from the primary to the intercooler with a side benefit of having the air entering the air/air cooler be at a much lower temperature(and hopefully lower coming out). At least that's how my brain is seeing it.
Nitrous is not an option for me.

RonA
 
RonA said:
I believe the secondary is a restriction and it seems like this would be a good way to allow it to more effectively move the air from the primary to the intercooler with a side benefit of having the air entering the air/air cooler be at a much lower temperature(and hopefully lower coming out). At least that's how my brain is seeing it.
Nitrous is not an option for me.

RonA
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I by no means claim to be an expert when it comes to these trucks, but from an aero/thermo standpoint I think it would work great. You could always go to a bigger secondary charger, but that would require more on the turbine side to drive it. When I get the chance I really want to do this to my setup and see how it does
 
Lostnwalmart said:
^^ I was actually just thinking about something like this, A small shot between stages and a big shot preintercooler.
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The one and only problem with that is it wouldn't be very cost effective and can't run it often. Not that Ron drives his much
 
97rada said:
The one and only problem with that is it wouldn't be very cost effective and can't run it often. Not that Ron drives his much
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It would be for racing purposes only I doubt I would need it while driving around.
 
gs1000 said:
CurtisEmery said:
Do you have temp probes before and after that new cooler? if so would you mind sharing your findings?
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We just did a test on my 95, 60psi exit pressure, and 460 deg exit temp, engine side (after the intercooler) didn't even register 100 degrees on the probe. Stock air to air intercoolers are very efficient for short bursts.
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Ron,

just ran a quick calc on my truck...

if I added a charge cooler between the stages, the charge temps to the engine drop from 215F @ 65 psi to 133F A 65 psi.

overall density ratio rises from 4.34 to 4.96

so, at 2000 rpm on a ISB5.9, the air flow would go from 77 #/min to 88#/min...in theory...


your results will be different...
 
Diesel Freak said:
Ron,

just ran a quick calc on my truck...

if I added a charge cooler between the stages, the charge temps to the engine drop from 215F @ 65 psi to 133F A 65 psi.

overall density ratio rises from 4.34 to 4.96

so, at 2000 rpm on a ISB5.9, the air flow would go from 77 #/min to 88#/min...in theory...


your results will be different...
Click to expand...

Thanks.
The thought of dropping the temperature of the air from 400+ down to under 100deg before it enters the secondary is very appealing. My secondary runs at a very low PR so I would imagine the air going into my air/air intercooler would be several hundred degrees cooler than it is now.

RonA
 
Diesel Freak said:
if I added a charge cooler between the stages, the charge temps to the engine drop from 215F @ 65 psi to 133F A 65 psi.

overall density ratio rises from 4.34 to 4.96

so, at 2000 rpm on a ISB5.9, the air flow would go from 77 #/min to 88#/min...in theory...
Click to expand...


How again, does one increase mass flow rate through the system by simply adding a heat exchanger?

The density increases, yes, but mass flow rate is constant until you actually change the fan curves and/or engine speed (i.e. turbo selection and tuning). Or... increase mass flow rate via nitrous.

Joesixpack hit the nail on the head in post #25.
 
Hurley said:
How again, does one increase mass flow rate through the system by simply adding a heat exchanger?

The density increases, yes, but mass flow rate is constant until you actually change the fan curves and/or engine speed (i.e. turbo selection and tuning). Or... increase mass flow rate via nitrous.

Joesixpack hit the nail on the head in post #25.
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if you raise the density and keep pressure constant, mass flow rises since velocity and area are also constant.

Continuity applies (Density x Area x Velocity)= Mass Flow

Fan laws still apply...and the turbo will have to work harder
 
Diesel Freak said:
if you raise the density and keep pressure constant, mass flow rises since velocity and area are also constant.

Continuity applies (Density x Area x Velocity)= Mass Flow

Fan laws still apply...and the turbo will have to work harder
Click to expand...


ehhhh.... I would venture to say that velocity decreases. Mass flow is a constant for these situations, however 'energy density' increases.
 
Post #25 shows conditions at two different temps AND pressures.

If I remove energy from the system, then the gas density rises, so for a constant pressure, more mass can flow thru the system at constant pressure...which is the reason for intercooling.
 
the other reason for intercooling is to allow lower boost pressures and still allow the same ammount of air into the engine...thus lowering pumping losses
 
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Diesel Freak said:
the other reason for intercooling is to allow lower boost pressures and still allow the same ammount of air into the engine...thus lowering pumping losses
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Which is exactly what post #25 demonstrated...?
 
yes it did...but looks like we are arguing symantics..

I would add the charge cooler, and either keep boost pressure the same ...or raise it...and in Ron's quest for yet MORE power...he will most likely raise it...
 
Diesel Freak said:
yes it did...but looks like we are arguing symantics..

I would add the charge cooler, and either keep boost pressure the same ...or raise it...and in Ron's quest for yet MORE power...he will most likely raise it...
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we wouldnt have to argue if it were not for the sEmantics :stab:
 
I sent info to two places that make air/water coolers showing allowable space for mounting. Hopefully one will be able to make something for it. The tank is pretty simple, but I want to research the pump a bit to be sure and get a good one. My luck with electric pumps isn't so good.:hehe:
 
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