How is the ES44AC/DC so much more fuel efficient than other locomotives? I think GE has made the compression better. (hence the V-12 producing the same amount of hp as a V-16) Anything else different?
Justin
4 less cylinders for 1. The 710’s in the Thundercabs are V16.
They use magic and pixie dust, plus some reverse engineering from a UFO they have hidden in Eire, Pennsylvania.
Bzzz…wrong answer. The EVO V-12 engine has more displacement than the EMD V-16. In other words it is a larger engine, but is much more fuel efficient.
Check Area 51 [alien]
On ultra low sulphur diesel, the two locomotives tested in this government test were the BNSF 7736 (ES44DC) and UP 8354 (SD70ACe). The fuel economy gap you suggest, GP40-2, isn’t as large as you might think. Remember that the GE press release that says the GEVO is 6% better than the 16-710G3C-T2 engine is put out by the company that produces and sells that GEVO engine, so you need to dig somewhere else for the REAL truth.
BSFC between the two above mention engines are as follows:
BNSF 7736 BSFC 0.370 lbm/hp-hr
UP 8354 BSFC 0.372 lbm/hp-hr
So while the GE does win in the above numbers, it ain’t by 6%.
Also keep in mind that the current incarnation of the 710 engine (remember it’s a two stroke), is 3% BETTER than that of the old 7FDL16 used in the AC4400CW.
Ok so it’s a larger engine, but how does it get it’s larger displacement? Actually what is displacement in prime mover terms? This may sound silly, but is the bore width/length longer? What I’m trying to ask is how did GE get this bigger EVO block to be more fuel efficient?
Justin
GEVO cylinders are 250 bore, 320 stroke, aren’t they? That would make them 35% larger than a 710 cylinder. No idea what the compression ratio is.
Off of the information I have been able to find there is very little displacement difference betwee the 12 cyl EVO and the 16 cyl 710 that EMD is using
EVO 9.84 in. bore x 12.59 in. stroke x 12 cyl = 11397.87 cu.in.
710 9.02 in. bore x 11 in. stroke x 16 cyl = 11246.45 cu.in
in theory, more cubic inches should consume more fuel.
More advanced design and better control systems. In addition, the EMD 710 is pretty much at its limit producing 4,300 HP. The 12 cylinder EVO can comfortably produce up to 5,500 HP via software changes with no loss of availability.
Actually, they have it hid in right under the main lobby…
Both EMD and GE have Fuel injection, computer management but the GE is a four stroke diesel motor. Do a little research on four stroke designed motors and compare them to the EMD two stroke motors. The two stroke motors are not as efficient from what I have read about them. I personally like them and the sound is great, but the GE’s using the four stroke design motors have been slightly more efficient. You can’t believe the hype that GE is making about all of their products. They are getting a lot of Government money from the green industry and must create ads to hype the deal. EMD is now based in Canada and will probably not be able to compete much longer.
The overall fuel savings is important to railroads with the high cost of fuel and the GE’s have sold extremely well in the past fifteen years. GM had been trying to sell of the EMD line for almost twenty years since the SD50’s came out and that attitude probably hurt their research and development of better fuel management.
CZ
The displacement of a cylinder is π times the radius squared (half the bore squared), times the stroke. Then multiply by the number of cylinders to get the displacement of the engine.