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M_Bailey

sequential turbo idea.. kinda

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So I this thought while laying in bed last night... First off im kind've familiar with how a true.sequential turbo set up works with the check valve and dropping the primary turbo out after the secondary turbo kicks in. but.... what if you run your exhaust in the primary turbo and out just as it would normally function, then run the compressed air from the primary turbo into the exhaust side of the secondary turbo but Instead of dumping that "spent gas" out the exhaust run it to intake and then run the compressed air from the secondary turbo just as you normally would to the intake. I would assume one could just use a "y"" pipe to connect the intake to the two turbos.

 

Would this work?

 

 

P.s. In my head I would run the same boost pressur on both turbos but since the second turbo is larger there would be an increased volume at the higher rpm

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I would plan on using an intercooler and yes the secondary turbo would be drivin by only the primary.. Im starting.to see volume problems.with that now

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This has issues with the First Law of ThermoDynamics:  Energy is neither created not destroyed.  You can not get any more energy out of the second turbo then you put into it. 

 

Although it is conceivable that some of the heat energy from the Primary's output stream might be converted to kinetic enegy in the exhaust turbine of the Secondary (and thus into pressure and volume in the outlet), it is far more likely that the ineffiencies of a mechaniical system will just turn more useful energy into low-level waste heat.

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Not wise, just questioning/cynical.  ;) No progress occurs without questioning "common knowledge", so keep thinking.  Just keep in mind that the Laws of Physics aren't just a good idea... they are the Law!

 

(As in: No, you can't "burn" water, it is already "burned" to its lowest energy state.  And, lacking "Maxwell's Daemon", perpetual motion is not possible.)

 

Edit: what I had originally typed at this point was too much like a thread hijack, and little relevance to this thread.  So, I removed it. :endEdit

Edited by NorthWet

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also, this is why turbochargers are made with the compressor side typically bigger than the turbine side. 

 

but, nobody really bothers with sequential turbo setups these days. most setups are parallel, where all the turbos run at once. cummins diesel guys have made 1200hp and 2500ft lbs with parallel setups... very rarely sequential. 

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also, this is why turbochargers are made with the compressor side typically bigger than the turbine side. 

 

but, nobody really bothers with sequential turbo setups these days. most setups are parallel, where all the turbos run at once. cummins diesel guys have made 1200hp and 2500ft lbs with parallel setups... very rarely sequential. 

Commercial diesels are a different world, as are aviation uses.  The wide-range flexibility that MIGHT come from sequential turbochargers is irrelevant in applications where gas volumes vary little. 

Edited by NorthWet

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