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Jet Turbine Locomotives
An anonymous submitter writes "I saw this article in the paper today. Not only is it lighter than a comparable diesel engine, it should burn the fuel more completely and be a bit better for the environment. Not to mention it is much faster. They should make more of a point that the North American railway system needs a major overhaul in order to support faster trains." The Department of Transportation has some information about next-generation trains, including a design incorporating a flywheel to improve acceleration.
If you were willing to foot the extra bill for one of these in new trains that you bought (assuming that you buy trains) it would have more advantages than just efficiency and speed--can you imagine how cool this would look in an advertisement?
I hate flying. The cramped seats. The claustrophobia. The ridiculous rules about standing and walking around...
I'd much rather travel by train, but it's always been much too slow. Even though these new trains are still slower than flying, they make up the difference quite a bit.
A smooth, relaxing train ride where all seats are Business class or better? Sign me up.
I guess they could be clearer, but I doubt this locomotive uses the jet engine for propulsion, rather it uses the jet engine to generate electricity that drives the same gigantic electric motor that moves the train today. Although the engine is a much higher-tech device to maintain than a diesel engine, it should be cleaner and possibly quieter as well.
You can go faster because a turbine engine that generates the same kilowatts as a conventional diesel does will be lighter. Less weight can equal more speed.
All that said, I'm not sure that "less weight" is a priority for most locomotives. If I remember correctly, the enormous weight of the locomotives is critical in pulling literally miles of loaded box cars up an incline. Of course, passenger trains are packed with very low density compared to freight, so maybe that's what this is for.
Yes, the old gas turbines. Fast and fuel-efficient at high speed, but it's a fact of life in railroading that locomotives spend most of their lives idling in one yard or another. UP found that they sucked fuel almost as fast idling as at full throttle. "The turbines burned about 90% of max HP fuel at idle so they would shut the turbine down going down longer hill. BIG THING, is you never stopped turning the turbine hot because the shaft was so long/heavy that it would sag when hot and you would never get it turning again. If you did it would be somewhat out of balance and shake the heck out of things." -- http://www.northeast.railfan.net/turbine_faq.html
Cool engines though, and other than the fuel consumption at idle, they were successful experiments.
I have seen several Freight Trains powered by gas turbines.
t m
http://www.railpower.com/2support/locomotives.h
I looked into train travel a couple months, Florida to St Louis and it was more expensive than airfair.
The trip would've taken longer than a bus too.
So, no cheaper than airplanes and it takes longer than a bus... any wonder hardly anyone travels via trains anymore?
We want fast or cheap. Trains are neither right now.
I had read about early attempts to use this technology to power trains, but I seem to recall some heat dissapation problems. I believe it was when these locamotives were stationary beneth things like overpasses and tunnels that they had problems with the output from the jets burning/melting things. My guess would be that they solve this using some of the same technologies they use to reduce the heat signature of aircraft.
If you look at the weight of a fully loaded train and the weight of an unloaded one you will see they are very close. A light weight train car will weight in at 50,000 lbs and can carry less than 3 times that. When the average loads these carry are a few pallets and is typicaly less than 10% of the weight of the car. The result is a huge mass that gets moved and that takes energy.
The reason train cars weigh so much is so they don't come off the track when they are pulled around corners. Even with the large radius curves on trainlines, the side forces of a mile long train with a fully loaded car at the back will be quite high. The early solution to that problem was to make the train cars weigh more and the result is now all trains cars fit into a standard weight. This also makes passenger trains weigh far more than they should. The US rail industry could save a major part of its energy bill by introducing a lighter train standard but that would cost a fortune in new rolling stock.
The "seven trains operating since 1977 in New York State using jet turbines
incorporated into coaches." are awful trains.
I remember when they went into service and replaced the nice big heavy comfortable
slowish trains, with a lot of room, real dining cars, and seats that were
like chairs. Then Amtrak bought these turbo trains from the French. They are
not at all nice, lighter weight, uncomfortable, slowish trains with not much
room, snack cars, and seats that are like airliner seats. ( Some moron
at Amtrak probably thought they were loosing business to the airlines
because people like those airline seats.)
They were always getting disabled every time they hit a snowmobile because
they were so fragile. They were supposed to be fast, but they aren't because
the rail beds are so crummy.
Fast trains aren't fast if they are on slow tracks, and until Amtrak
can get their own tracks the freight trains will keep messing up the rail
beds for all these fast trains.
And they smell just as bad as diesel trains, because there is no
difference between the jet fuel they use, and diesel fuel.
At around 200mph, easily achievable using current train systems if you got high speed rail all the way, you should be able to go from downtown San Francisco or LA to New York in 15 hours. That is actually not that different from air travel if you take into account all the overhead associated with air travel (security, parking, transportation to/from airport, etc.), and it's a whole lot more pleasant. With improved technology, perhaps one could even get that down by a few more hours. And trains don't fly into buildings either.
I had the chance to cruise on the Millennium last year, which has two gas turbine engines hooked to electrical generators which both supply energy to the ship's power grid and also power the motors driving the propellers. I'm sure kilotonnes of ship will help silence the engines, so I can't speak to noise, but they were amazingly vibration-free, unlike more common deisel engines with a direct physical linkage from engine to drivetrain to prop.
I'm not sure how that translates to train use, but I'm curious to find out. Considering that they'd probably provide electricity to power the wheels, I wonder if a sufficiently sized flywheel arrangement or battery bank could mean that the engine could operate at constant speed, preventing the frequent idleup and idledown which creates a much more distracting noise at a distance than the noise of a constant engine...
Kevin Fox
That's true, however, note that I said that when talking about people moving, trains were dead. the military, for example, loves trains because it moves all their tanks that way.
However, in cargo moving speed is not necessary. Aircraft handle the high speed, low volume traffice quite well.
Do you know why the road less traveled by is littered with the bones of the unwary?
We also have a Congress who feels that Amtrak should be paying its own way, and not requiring federal subsidies.
Meanwhile, just how big is the tax infrastructure that's already in place supporting our road and highway system? Road traffic is really *heavily* subsidized by our taxes, and not just the ones at the pump, tires, and vehicle registration.
I've also heard that there's a heavy federal infrastructure involved in air transport, though I know nothing of the breakdown there between private and public sector. I remember Reagan ordering the air traffic controllers back to work, suggesting public sector, there. (I don't remember Taft Hartley being invoked, though it may have.)
The living have better things to do than to continue hating the dead.
At one meter, how loud in dB would something have to be for a deaf person with their back turned to realize a tone was being generated? And does the frequency matter?
slashdot: where everyone yells sarcastic metaphors to themselves to understand the issue
Although this looks promising on paper, one can but wonder if that turbine locomotiveis yet another boondoggle (sp?).
Given that the turbine's fuel appetite does not significantly changes when the turbine goes from idle to warp factor nine (unlike a diesel), one wonder what fuel economy will be with a SINGLE 5000 hp turbine engine. Okay, granted, with hotel power (to light-up the cars and air-condition/heat them), you still suck some power from the engine when the train is stopped.
One would think that a sensible way to address this problem would be to use 10 smal 500 HP engines whose number that kick-in would depend of the power needed at a time. But of course, this would mean higher maintenance costs and more chances for something to go wrong. However, modular design could make it easy to replace a turbine.
Even if we end-up with a super-magical turbine locomotive that runs all the time and doesn't suck fuel all the time as well, we'd face a little problem that is caused by the turbines's very suitableness for powering aircraft: low weight.
Of course, low weight means less power needed to go at high speed. But is means also less weight on drivers. Perhaps railroads will be clipping newspapers coupons looking for sand clerance sales (sand can be injected right in front of driving wheels to boost adhesion if the wheels start to slip Wheels will definitely slip if there isn't enough weight on them)...
So, one wonders of the suitableness of a turbine locomotive-hauled passenger train. Will it slip? Will it haul? I'm afraid that a turbine
engine will have to be weighted up... But that weight need not be always deadweight. Big cities call for big commuter train traffic: the thing electrification is for. So, why not add a pantograph and power transformer allowing for full-power operation under catenary when approaching terminals? At least, this will reduce downtown air pollution.
Wouldn't a better way be to have distributed traction throughout the train? You keep power generation in a lightweight power car (it would hardly be a locomotive anymore), and have traction motors throughout the train itself, so to take advantage of the weight there, too. Smaller traction motors, too, or at least, bigger derated ones. The first french TGVs had powered axles under the passenger coaches, and the Hikari Japanese bullet-trains running on the Shinkansen, as well as the newest german ICE trains have distributed powered axles through the trains (and the ICE-3 trains are real neat, too because the front seats of the first cars look on the track ahead, over the engineer's shoulders).
But of course, one hits other problems, such as safely sending traction power throughout the train. You're talking at something like 1000 amps at 600 volts there. Coupling/uncoupling cars would cause problems, and at each car, you also have connections that can go wrong. 100 years ago, in Paris, a subway train caught fire, killing more than 100 people. The cause: high-intensity traction power sent through flexible cables throughout the train. Such lessons from the past are not easily forgotten...
An lighter articulated train would be better in this respect, but then, you end-up with with an unflexible consist.
But, again, adding cars and removing them is expensive, more expensive than hauling around empty seats (or it seems, looking the way some MBAs with adding machines seem to think in railroad adminive departments). But, after all, the french TGVs are articulated, so this is less a problem it might see.
Aha! Let's compromise on, oh, four car articulated, self-contained (1 first class parlour/club-car, 2 second class coaches, bar car & checked luggage/bicycle space with reversible control cab) units, two of which could be powered by one power car. So a 16 car train could be feasible, and you can retain some flexibility.
And then, do we have a tilt-train ? Tilt-trains are attractive, but is still one more thing that can go wrong. And with motorized trucks, you have less room to put the needed power-banking mechanisms...
It should work politically: engineers looove that kind of contraptions! And politicians looove to be associated with forward-thinking technology... But what kind of engineers? Aircraft engineers are clueless about railroad problems (one should remember the woes suffered by the late UAC turbo train), and railroad engineers are justifiably wary of sleek lightweight technology that falls apart at the slightest rail joint...
I am afraid that having efficient turbine power for high-speed passenger trains would end-up in a costlier, less flexible exercise than using electrified off-the-shelf technology in the long run...
Boil something with it, turn another turbine, generate more elecricity.
Send lawyers, guns, and money!