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Old 09-12-2014, 11:51 AM   #13
WTF
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Quote:
Originally Posted by wparsons View Post
How are you expecting the twin screw to flow more air than it already is at a given RPM? Pressurizing the air before it gets to the blower won't make it flow more air...
Yes it does.

That's what "compound boost" is all about. It multiplies whatever is fed to it.

Rather than trying to explain from scratch, here's something prepared earlier, from Wikipedia: "compounded boost is always produced as the pressure ratios of the two compressors are multiplied, not added. In other words, if a turbocharger which produced 10 psi (0.7 bar) (pressure ratio = 1.7) alone blew into a supercharger which also produced 10psi alone, the resultant manifold pressure would be 27 psi (1.9 bar) (PR=2.8) rather than 20 psi (1.4 bar) (PR=2.3). This form of series twincharging allows for the production of boost pressures that would otherwise be unachievable with other compressor arrangements and would be inefficient."
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