13B Power @ 1 bar absolute pressure, to see what you might have if you MAN UP!

Mitchocalypse · 11-30-2012, 11:41 AM

Hmm. I've often thought about this exact concept and would have applied it exactly the same as you have but the more and more I thought about it, the more i found things that might throw off the approximation so I pretty much just dismissed the idea.

Have you tested how accurate this is? Maybe it's just the way i'm looking at it but it almost seems over simplistic. I'm sure it gives a reasonable approximation - but how accurate is my question?

The two biggest things for me are intake air temp and volumetric efficiency. Obviously i don't need to explain the fundamental gas law, but I was also under the impression that at higher rpms, internal combustion engines (n/a) could reach greater than 100% volumetric efficiency so the absolute pressure in the manifold (or combustion chamber) could be greater than 1 bar absolute.

The way I'm looking at it (and I know I'm missing some things) is that doubling the absolute pressure wouldn't actually double the power.

Sure it's a good approximation, but how good?

11-30-2012, 11:41 AM	#4
Mitchocalypse Rotary Fanatic Join Date: Jun 2012 Location: Edmonton, AB Posts: 179 Rep Power: 14	Hmm. I've often thought about this exact concept and would have applied it exactly the same as you have but the more and more I thought about it, the more i found things that might throw off the approximation so I pretty much just dismissed the idea. Have you tested how accurate this is? Maybe it's just the way i'm looking at it but it almost seems over simplistic. I'm sure it gives a reasonable approximation - but how accurate is my question? The two biggest things for me are intake air temp and volumetric efficiency. Obviously i don't need to explain the fundamental gas law, but I was also under the impression that at higher rpms, internal combustion engines (n/a) could reach greater than 100% volumetric efficiency so the absolute pressure in the manifold (or combustion chamber) could be greater than 1 bar absolute. The way I'm looking at it (and I know I'm missing some things) is that doubling the absolute pressure wouldn't actually double the power. Sure it's a good approximation, but how good? __________________