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Piping loss with air-turbocharger

Piping loss with air-turbocharger

Piping loss with air-turbocharger

(OP)
Air at 1000 CFM 80 degrees, sea level, enters a turbocharger for compression. Exits the compressor at 500 F, 32 psig, enroute to the CAC.

What is the air pressure loss for 4 feet (one sweep 90) of:

1.75" id pipe
2.5" id pipe

Thanks all.

RE: Piping loss with air-turbocharger

(OP)
oops, sorry for the typo.  Compression is 18 psi, 32 absolute.

RE: Piping loss with air-turbocharger

Is this homework?

Is the sweep 4' long?  If not, what's r/d?

Good luck,
Latexman

RE: Piping loss with air-turbocharger

(OP)
I'm a little old for homework,  one sweep , a 6" radius will suffice.

RE: Piping loss with air-turbocharger

1.75" id pipe: dP = 15.9 psi. Flow is sonic and T = 386 F at the exit.

2.5" id pipe: dP = 1.02 psi.

Good luck,
Latexman

RE: Piping loss with air-turbocharger

That was the adiabatic solution.

Good luck,
Latexman

RE: Piping loss with air-turbocharger

(OP)
WOW!  That is a bit shocking.

Can you give me an idea how you did the calc, or which tables you used.

FYI, this is a turbocharger application.  What you are saying is that the turbo would have to work to produce 15.9 psi, just to get the compressed product through this pipe.

(BTW this pipe leades to the charge air cooler, where the charge is air-air cooled to 180 degrees.)

RE: Piping loss with air-turbocharger

I plugged the numbers into my handy dandy spreadsheet, that's how I did it.

The spreadsheet is based on adiabatic compressible flow equations in Shapiro's "The Dynamics And Thermodynamics of Compressible Fluid FLow".

Good luck,
Latexman

RE: Piping loss with air-turbocharger

(OP)
ok.  How do I get a copy?  Is it on cd somewhere?  Or is it a formula out of a book?


Or if someone else can point me in the right direction to "learn how to fish"  I would be grateful.

RE: Piping loss with air-turbocharger

There are many, many fluid flow and thermo books that have the equations for adiabatic pipe flow.  Some other books that I know of are Perry's Handbook, McCabe and Smith's Unit Operations, Ron Darby's Chemical Engineering Fluid Mechanics, Crane Technical Paper 410, and my old college thermo book (1976) by Balzhiser, Samuels, and Eliassen.  To be honest, a Chemical Engineer that doesn't know where to find this information is quite puzzling to me.  Try searching Google for "adiabatic pipe flow".  I got 39 hits.  At least one should have the equations.

Good luck,
Latexman

RE: Piping loss with air-turbocharger

(OP)
LOL, I understand what you mean.  I have my unit ops book right here.  Covered with 15 years worth of dust.

Spent the last decade and a half doing everything but CN work.  

Your tips have saved me a lot of time.  Guess it is now time to reaquaint myself with these old books.

Thanks again

RE: Piping loss with air-turbocharger

CN?

Good luck,
Latexman

RE: Piping loss with air-turbocharger

Btw, what are you running 18 lbs of boost on with 1000 cfm?  Must be a big block.

Good luck,
Latexman

RE: Piping loss with air-turbocharger

(OP)
Actually the 1000 cfm was an overshoot.  More like 800 cfm, 18 psi, around 45-50 lb/min

Stock duramax turbo-diesel, 6.6 L

RE: Piping loss with air-turbocharger

(OP)
CN (chemical engineering) was differentiated from Civil Engineering (CE) at Lowell U

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