Ok, here we are with these tranmissions!! Do we really need them?? Look at this generator. If we had that generator in our coaches and motors at the wheels like a train, could we improve fuel mileage? Bill T.
Freight per pound per mile is much cheaper than trucks period. The picture is of a 671 with a generator behind it. Seems to be worth considering if we can beat the fuel increases. And you could use your battery banks as a hybrid. Bill T.
Interesting, but I suspect that, as someone else observed in another thread, the rolling efficiencies of steel wheels on steel rails accounts for much of the efficiency. Plus the efficiency of the volume. I would bet that running a locomotive by itself is much less efficient per pound than when pulling its share of freight cars.
In my weird dreams I have thought about trucks and buses on special highways where they would connect together like trains. Perhaps 10 to 15 rigs in a train. Computer controls would have each truck or bus contribute it's share of motive power and would control brakes and steering.
As you approached your exit, your rig would unhook and peel off and the rest of the train slowly come back together. I would guess each individual rig would be approaching 30-40 MPG.
Len (the dreamer)
That may happen one day, but until then, you have to think about cooling with the trucks being closely spaced without frontal air ram. On a bus, not a problem though. Realistically, the combination of very low rolling resistance with steel wheels and only 3% grades makes for very low power to weight ratio possible. How many times have you seen a train laboring up a grade at maybe 10mph? I know that would go far with the public. More and more, you'll be seeing hybrid buses and trucks. I know Freightliner has a hybrid straight truck up to 26,000lb gvw that can get 20% better fuel mileage than straight Diesel. I know most would rather get 10mpg than 8mpg. Good Luck, TomC
very interesting RG Letourneau introduced the concept to the construction industry in the 1950s and it is still in use today on large mining equipment
Quote from: TomC on April 18, 2008, 07:18:12 AM
How many times have you seen a train laboring up a grade at maybe 10mph? Good Luck, TomC
The little train that could "I think I can" "I think I can" "I think I can" ;D
Quote from: Len Silva on April 18, 2008, 07:09:53 AM
In my weird dreams I have thought about trucks and buses on special highways where they would connect together like trains. Perhaps 10 to 15 rigs in a train. Computer controls would have each truck or bus contribute it's share of motive power and would control brakes and steering.
As you approached your exit, your rig would unhook and peel off and the rest of the train slowly come back together. I would guess each individual rig would be approaching 30-40 MPG.
Len (the dreamer)
The technology already exists - Mercedes and Lexus already have models where the cruise control uses radar to maintain an even gap from the car in front. If you were to reduce the distance to just a foot or so between vehicles then there would be serious aerodynamic gains to be had.
Having a mechanical linkage between the engine and wheels is of course fundamentally more efficient than converting the power into electricity and then back again, but there are other reasons why diesel-electric locomotives make sense. Rolling resistance on road vehicles is a major user of fuel, and this is something that is getting steadily worse as tyres get fatter due to vehicles getting heavier and travelling faster. And triple axle buses with eight tyres on the road are never going to be easy to push along.
Jeremy
When I saw "Train Solution to Fuel Prices!!!" I was expecting:
Put coach on flatcar
flatcar takes coach 90% of the way to destination
take coach off flatcar.
Yeah, railroads and trains are cool, but they are kinda limited to around 1% grades or sossss, sometimes a little bit more. Trains also bust a literal hole in the air sossss they experience/enjoy some aero-dynamic advantages alsos. I also think a linked "consist" consisting of a bunch of Bus Conversions would be sooss cool. :) :) :)
There are people that convert railroad cars to personal coaches and pay Amtrak to pull them where they want to go.
the private rail coaches, are not only extremely expensive, both to make/rebuild, but also to bring up to standards.
I once looked into the costs for this sort of thing...was not a deal at al even if you had the car done for free.
every time there was a hookup to a train was somne awefull expense, then a in yard move was another chunk of change, the actiual cost once on a consist was not that bad....but the pretrip moving etc was almost as much as the trip itself.
Yeah, but it rides like it's on rails!
Quote from: Lin on April 19, 2008, 12:11:41 PM
Yeah, but it rides like it's on rails!
Yup, and if you see something along the way you would like to get a closer look at, too bad. Also, if you want to bring along a car, more freight charges and handling charges. And if it is only Amtrak that pulls them, they have really limited routes. I've heard that a freight train is not allowed to include passenger cars.
All things considered my opinion is that a bus conversion is a better choice than a rail car conversion.
Regarding efficiency; You gotta consider that a diesel-electric railroad locomotive uses the same hardware for two different functions.
When pulling, the diesel engine powers a big generator or alternator (depending on the age of the locomotive) to send power through big switches called power contactors, to motors (called traction motors) that are geared directly to each axle. The electrical configuration of the traction motor circuits can be changed, automatically, during operation, from series (maximum starting torque) to series parallel, to parallel. Also, part of the field current is shunted to resistors at optimum times to help motor circuits operate at peak efficiency.
When coasting, the configuration of the traction motor circuits can again be changed through the cab control console so that the traction motors become generators, with their output current dissipated at heat at grid resistors. The control console varies the field current in the traction motors. The stronger the field current, the more braking effect of the motors. Dynamic braking.
I think I got that right...
Dennis
Quote from: Hi yo silver on April 19, 2008, 05:39:51 PM
Regarding efficiency; You gotta consider that a diesel-electric railroad locomotive uses the same hardware for two different functions.
When pulling, the diesel engine powers a big generator or alternator (depending on the age of the locomotive) to send power through big switches called power contactors, to motors (called traction motors) that are geared directly to each axle. The electrical configuration of the traction motor circuits can be changed, automatically, during operation, from series (maximum starting torque) to series parallel, to parallel. Also, part of the field current is shunted to resistors at optimum times to help motor circuits operate at peak efficiency.
When coasting, the configuration of the traction motor circuits can again be changed through the cab control console so that the traction motors become generators, with their output current dissipated at heat at grid resistors. The control console varies the field current in the traction motors. The stronger the field current, the more braking effect of the motors. Dynamic braking.
I think I got that right...
Dennis
These are DC motors, not AC I believe.
Richard
Quote from: Hi yo silver on April 19, 2008, 05:39:51 PM
When coasting, the configuration of the traction motor circuits can again be changed through the cab control console so that the traction motors become generators, with their output current dissipated at heat at grid resistors. The control console varies the field current in the traction motors. The stronger the field current, the more braking effect of the motors. Dynamic braking.
Too bad they don't capture the electicity generated during dynamic braking into storage batteries that would then contribute a power boost for acceleration.
I have a close friend whose job is to maintain a 1921 rail car for the heir of a local banking family. He also goes along on the trips to help facilitate the connections. It cost about $1200 to go from San Diego to LA, although most of that cost is the hookup and drop off. Going to San francisco does not cost a lot more, its the connections not the mileage.
Very different pace than the bus. a lot of waiting, and slow cruising along. I like trains, and it s beautiful car, but I'm not sure I would want it even if I had the big $ it costs to maintain and use it. Way cool though.
80 ft long
16 ft tall
10 ft wide
440 volts and 32 volts
Original Honduran mahaony you look into the grain about a foot.
He had some carpets woven to match the original pattern.
he is having one of the coupler's redone, that thing weighs about 1500 lbs.
Most new locomotives are now completely A/C-meaning the Diesel engine powering an alternator (think really big 50DN) going to 3 phase brushless traction motors. Without brushes, there is no dynamic braking capability-hence you can always spot an A/C locomotive because of the absence of the extra vents at the top of the engine cowl that would normally house the electric absorbing heating coils and fans. They can still get locomotive braking through the traction motors-when the driver selects dynamic braking, the motors are simply put into reverse. Course this is done by computer since adding electrical current to a 3 phase motor in reverse can twist it apart, the amount of current applied is very low for effective braking forces. Just a bit a trivia. Good Luck, TomC
Not sure how it compares today, but when I was shipping iron equipment it was considerably less expensive to put it on a truck than a train, and much less hassle arranging the shipment. FWIW, Will
I remember going to a train museum in golden Colorado. They has a few old buses( more like the size of a SUV) that had steel wheels attached to the underside. Their route was on the rails. It was a time before roads were very good. It would be nice at times to drive up to a rail line and attach to the tail end and let the train pull you along while you sleep in the back
Merle considered doing a 'railroad tour' many years ago and the cost of insurance is what killed the deal. As mentioned, freight trains couldn't be used to haul people. Amtrak agreed but it was going to be crazy to insure. The plan was to have the buses on flat cars and not play anywhere more than an hour from a railroad stop.
They are actually talking about trying it again this summer but with a slightly different theme. The 'Green Train' will promote global awareness on a sex week tour. I don't really agree with the global warming mumbo jumbo but the tour will still be cool.
Quote from: Songman on April 20, 2008, 04:43:40 PM
The 'Green Train' will promote global awareness on a sex week tour. I don't really agree with the global warming mumbo jumbo but the tour will still be cool.
OK,
I'm not from California, you may need to explain this? :P
Cliff
Not from California either, but sounds like a week-long orgy to me. LOL :o :o ;)
I AM from California and i think I need that explained!!!
There is a trend with yard-switchers (think small locomotives that don't go on the open rails), to use a diesel-electric hybrid drive system now (BIG battery bank...).
The reason that the diesel-electric system is so widely popular, is that electricity is easier to move from one place to a another that mechanical energy is. Think about the losses in a diesel electric setup: diesel fuel to mechanical = ~30% efficiency, mechanical to electrical = ~80% efficiency, electrical to mechanical = ~80% efficiency. This means that roughly 20% of every unit of energy produced by burning diesel fuel is turned into actual work (and this is rough...). This doesn't add up to a very efficient system (and is why most transit systems stick with Electricity). The efficiencies of that electrical system go down when the system is run at less than its peak, so at low speeds a diesel-electric locomotive is wating a lot of energy as heat in the traction motors (and they have huge blowers to keep them cool).
The concept around hybrid drive systems is sizing the power generation side of the system so that it is always at or very near peak load and thus peak efficiency. Extra energy is stored in capacitor banks and/or large batteries, and called-on when the traction load is higher than the peak capabilites of the internal combustion engine (I.C.E.) portion of the system. If a hybrid system has a method of intaking power for storage that is not part of the I.C.E. side of the system, it may run on electricity for an extended period (or if the power doesn't go out - indefinately). This is the theory behind plug-in hybrids. I think it won't be long before we see switchers in yards with overhead wires - since it will soon be cheaper to run them off solar or wind power farms to "trickle charge" hybrid switcher locomotives when not at peak load (I mean think of it - if you have all of that track, why not put solar panels in between the rails for energy accumulation when a train isn't blocking the sun...).
Cheers!
-Tim
My Granddaddy was the Lead Engineer (most seniority) for the Pa and W Va railroad for many years and he did work there all his life as a fireman first. He did steam mostly but ended up on Diesel Locomotives. I learned more about how those things work listening to all of you than I ever did from all the years I spent with him. Not a bad guy though, understand. Thanks you all for a very interesting series of posts.
Europe, not wanting to import any more oil than absolutely needed, ships everything cross country by rail. Diesel trucks handle local distribution. Not quite a clear cut system and yes I saw lots of long haulers on the autobahns and highways of Spain and Italy. It is the reverse of what we have for a transportation grid and they manage quite well and use far less oil. The trains were killed so the oil people and the steel and rubber guys could reap the windfall benefits. Same with the streetcar and underground systems...bought, depleted and scraped to make way for GM buses. That is the story told in every College history book I have ever read. Makes a lot of people mad, and understandably so. Then again, those people that reject that history are "confused" about how and why this oil thing has gotten so far out of hand. History repeats for those that don't know history andsome of those lessons are terminal. The thread of oil and diesel runs through this post....don't think it is political...it isn't.
God Bless,
John
Gentlemen, There are at least two other ways to save fuel. Shorten your coach, or put it on rails! Bill T.
here is the bus or cars rather that o saw.
http://en.wikipedia.org/wiki/Galloping_Goose
not a bus but I though interesting.
http://en.wikipedia.org/wiki/Image:AX_ZIM_Railcar_SBug_Bridge_20061105.jpg
http://en.wikipedia.org/wiki/Road-rail_vehicle
http://www.youtube.com/watch?v=XsDPFZ4f550&feature=related
http://www.youtube.com/watch?v=fdtgyd0c-W4&NR=1
http://www.youtube.com/watch?v=CdoV30BY3OE&NR=1
Of course the real reason they do not do this is the real risk of a train hitting the back end of your bus that would be attached to the trian.