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trebuchet03 · 09-09-2008, 06:35 PM

I second rmay's comment on scale.

Engines (perhaps even in general) do not scale down very nicely - nice meaning that you keep internal losses proportional to output (such in the case of reciprocating engines) or bypass ratios (Such as Pratt/Whitney's GTF with a bypass of 11:1 - but when scaled down, that figure dropped to 10:1 --- FTW: higher bypass means less fuel consumption).

Just remember - every 747 you see fly by is a 140KW power plant in the sky... The US commercial airline fleet has a combined output around 1 terrawatt (US power production is ~6TW)... And I'm gonna stop before I digress too much more

09-09-2008, 06:35 PM	#41 (permalink)
trebuchet03 MechE Join Date: Dec 2007 Location: Bay Area Posts: 1,151 The Miata - '01 Mazda MX-5 Miata Thanks: 0 Thanked 22 Times in 18 Posts	I second rmay's comment on scale. Engines (perhaps even in general) do not scale down very nicely - nice meaning that you keep internal losses proportional to output (such in the case of reciprocating engines) or bypass ratios (Such as Pratt/Whitney's GTF with a bypass of 11:1 - but when scaled down, that figure dropped to 10:1 --- FTW: higher bypass means less fuel consumption). Just remember - every 747 you see fly by is a 140KW power plant in the sky... The US commercial airline fleet has a combined output around 1 terrawatt (US power production is ~6TW)... And I'm gonna stop before I digress too much more __________________ Cars have not created a new problem. They merely made more urgent the necessity to solve existing ones.