This is the Mercedes-Benz S400 CDI. It's a turbo diesel that is limited by its onboard computer to a top speed of 155 MPH.
Not sure what kind of fuel mileage it gets, but who cares?
Posted on 10/09/2002 7:49:52 PM PDT by John Jamieson
VW Lupo "3 liter":100mph, 4 seats, airbags, automatic transmission, available AC. 78.5mpg city, 104.6mpg highway, 94.5mpg combined. If we can get the sulfur out of US desiel fuel, we could have 'em now!
(see link for details)
would you get good efficiency? I thought you lost energy at each conversion- ie. chemical to mechanical, mechanical to electric.
Thoughts?
This is the Mercedes-Benz S400 CDI. It's a turbo diesel that is limited by its onboard computer to a top speed of 155 MPH.
Not sure what kind of fuel mileage it gets, but who cares?
Not much different from any VW....
Diesel engines aren't known for being short lived.
Ever hear of a gm 5.7 liter diesel?
Go for a Golf GTI VR6 with nitrous... it's funny how everyone else looks like they're standing still when you pass them at 120
The two principal reasons that the electric drive system is used in railroad locomotives are
1) The great difficulty of transmitting 1000-6000 HP from the chassis to the axles, which are on trucks that move with at least three degrees of freedom with respect to the frame.
(Consider a complex set of splined shafts and universal joints in the 1000 HP range, in comparison to a couple of 2" diameter braided wires.)
Electrical transmission beats any purely mechanical kludge so much in reliability and maintainability that the railroads accept the complexity of the electric components, and the conversion losses.*
2) Ease of controlling speed and torque at the high power levels involved. The electrical speed control systems at the time of diesel-electric widescale introduction (at the end of the 1930's) were already more than competitive with any equivalent mechanical clutch/torque converter/transmission. The gap probably widened in the ensuing 60 years, with the development of increasingly sophisticated solid state power control.
In addition, the newer generation of locomotives feature computer-controlled traction maximization, which would be much harder to do in the mechanical domain.
Note that in automotive use, the problem of transferring torque to the axles is less complex, partly because of the lower power levels, and partly due to the smaller relative motions.
A secondary reason for going to the hybrid auto is to put an electric motor at each wheel, simplifying the suspension and allowing better traction control (as mentioned above for modern locomotives).
The more important reason for the hybrid, however, is to allow the internal combustion engine to shut down for various periods of time, to avoid wasting fuel at idle or very low speeds. An additional benefit is that the engine can be designed to run at a single RPM for maximum efficiency. The tradeoff to get this gain is the cost and weight of the battery required.
*- A German firm makes a diesel-hydraulic locomotive that has advantages similar to the diesel-electric. A US railroad tried a few about 20 years ago but eventually got rid of them. Some observers claim that the main problem was the unfamiliarity of the railroad's mechanics with the technology. Since that time, the advances in electric traction control can probably not be duplicated well in the hydraulic domain, leaving diesel-electric the technology of choice.
Unless you have catenary available, of course, in which case you just leave the diesel part off <)B^).
I LIKE IT!!!!
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