Why are trains no longer streamlined ?
 

Yes - I know passenger trains such as the TGV, and Japanese bullet trains are all beautifully designed for good aerodynamics, but what about freight trains ?

You would think that they could at least do a half arsed attempt at it with the freight trains. Looking at freight trains, it almost looks as if they design the trains like a trailer house - complete with exposed ladders, wind catching roof overhangs, and exposed railing.

Even at the slower speeds that they travel, they would probably save several thousand gallons of fuel each year simply by a more 'retro' streamlined design.

So where did the old streamliner designs fail so badly that the newer trains had to throw the old designs to the wind ?

There are still trains?

My guess is, there's too much variation in cars and containers to even bother with it. And, they don't really get going all that fast.

Aero drag has to be darn near negligible compared to the frictional losses of umpteen thousand tons.

At least they would look cool :)

Actually they are looking aerodynamics. They have looked at placing dividers in empty coal cars and reduced drag by 21%.

well, they claim to be able to move a ton of freight over 400 miles on a gallon of fuel... and if their design allows for better maintenance and that allows for a longer lived train and a reduction in fuel used then I say to stick with the utility design.

The more squared-off shape is probably because repairs are easier. And since the aerodynamics of the leading locomotive on a 100+ car train is probably only a tiny portion of the overall drag.

For short trains, such as Metrolink commuter trains, the nose of the locomotives are now made rounded, and there are body skirts and smooth exteriors on the cars. I just wish they'd use Green Goats on them, since they tend to accelerate/decelerate every three miles, and bleeding off the momentum in the brakes and dynamics.

I'd like to see lightweight removable boattails on the end of the last car on long distance express trains. It should be easy to take off at the terminal station and put it on another train that's heading out. With speeds of 80-160 km/h here, and over 200 km/h in western Europe (and I don't mean TGV), maintained for hundreds of kilometers, the boattail and the extra work around it would quickly pay for itself.

Yeah really. They ripped up nearly all the tracks around here 20 years ago. The one piece of line that is left I have never seen being used.

I have always wondered about that commercial. Notice they only say fuel. Maybe it's uranium or plutonium.

They probably design them the way they do because it is cheaper and easier. It is always easier to build a box out of steel than any curved shape. And probably for industry standardization as well. Just like tractor trailers.

I thought that commercial was more like
"We can move 400 tons 1 MILE on a gallon."

Which doesent sound as impressive, but means the same thing, no?

400 miles per ton per gallon... That doesn't sound that great to me. A truck takes on 80 tons and gets 8mpg. So that's 640 miles per ton per gallon... am i missing something?

Don't diesel trains use the engine as a generator for the electric motors, like how that new chevy volt works.

The commercial states that a freight train can move 1 ton of freight 423 miles on a gallon of diesel. A truck weighs 40 tons (80,000 pounds.) However, it typically can only carry about 40,000 pounds of freight (20 tons.) That means that a truck can carry 20 tons of freight 8 miles on a gallon, which is equivalent to hauling 1 ton of freight 160 miles on a gallon.

[QUOTE=Cd;91183]

Even at the slower speeds that they travel, they would probably save several thousand gallons of fuel each year simply by a more 'retro' streamlined design.

QUOTE]

By the way, I was talking about an overall fleet average.

Katana : I saw a show on diesel trains that showed just what you are asking - the engine is hooked up to a large alternator versus a gearbox. So, yes it is sort of like a Volt in a sense.

I know nothing.
Experts : please take the floor.

Just looking at a few freight trains the other day and a couple of observations.

Most flat cars are two containers long and most box cars are built for maximum volume and ease of loading and off loading.

The trains I saw had an almost random set up of load and empty cars (ie: Engine , two or three flat cars with loads then a few with no loads then a few box cars and then a few more flat cars with no loads and at the end the guards van) with little if any thought given to aero effects.

Maybe those detachable type flaps fitted to truck prime movers may be an option?

Pete.

On a train, the lonng boundary layer builds up so thick that ladders and such are not as bad as they'd be on a truck. The cost and fuel involved in streamlining seem likely to outweigh the benefits, for common freight trains. They get their economy from steel wheels and drafting. It is unfortunate about the mix of flatcars and loaded ones, arising from convenience and destinations. The data on coal cars suggests that folding or inflatable fillers might be the easiest improvement to make.

Trains were designed for steam engines, and attempts to introduce lighter passenger cars have generally foundered on the need to deal with the "buffing loads" of two long trains coupling. A modern re-design could have each car powered by its own electric motors, so that the only couplers needed would be electrical sockets to the generator in the locomotive. The lightweight cars might also be designed as monocoques, smooth all over, with the wheel trucks only exposed from below.

Even if this were properly asserted, I haven't seen too many trucks that actually get 8 MPG, first of all, and to a truck, 640 miles is actually LESS overall distance than 400 miles is to a train.

Keep in mind, that the train goes straight, for the most part. It doesn't follow highways which go up, down, around, over, under, through, etc.

As far as railways in general being used, NS and CSX are the two largest that I know of... and the only two worth mentioning in the area, but there are several rail yards around here, as just about anywhere you'd find a mill or quarry, usually. (One that's been around since trains were in wide use.)

Yes, diesel engines are more properly called diesel-electric locomotives. There is a large diesel engine running that is connected to a even larger generator. This charges batteries and powers motors in each truck. Some of the larger locos even have 2x motors per truck. If you are able to look up the inner-workings of a modern day locomotive I think one would be impressed. (at least I have been since I was into model trains as a kid)

Wagonman hit the nail on the head with why cars are designed they way they are. They were first designed long ago when this stuff was not an issue, and since then the basics remain the same cause of ease of construction and maintenance. However, they are doing what they can to improve efficiently as they all want to make more profit.

As far as the big rail roads still around, CN and CR are the biggest ones around here. Otherwise you still have the BNSF (which will always be ATSF in my heart), UP, and the above listed. Most others are short lines (local railroads) or have been bought out.
As far as the markings on the side of tank cars and hoppers, the 4 letters ending in an X is a private owner, usually a business of sorts. The first three signify the company but I'm not 100% sure where to find that listing of who is who.

Although not really answering the initial question, I hope this was at least interesting.

Trains are actually surprisingly aerodynamic. As we know the rear is more important than the front. If you look at a train from 7,000 feet up, it looks like a spear on tangent track. Bicycle Bob was right, the boundary layer builds up fast and the grab irons don't matter.

A Chevy Volt, as a true series hybrid is more akin to a diesel-electric submarine. The battery drives the motors and the engine/generator charges the battery. Diesel-electric locomotives eschew the battery. They use electric drive because mechanical drive is limited in how much HP they can transmit. the biggest mechanical transmissions are about 1200 HP. Today's locomotive are in the 4,000- 6,000 HP range. GE has monkeyed with a series hybrid locomotive but so far it has been a dud.

Railroads are incredibly labor-intensive and railroad people make a very high wage, so railroads are always on the lookout for cutting the amount of work it takes to move the stuff.

The best way to cut railroads' appetite (quarter-million barrels a day in the US alone) for diesel fuel is to convert them to straight electric. Proven technology but VERY capital intensive and then there the question of where do you get all that electricity?

Source: Eight years with CSX and two years with EMD.

trains
 

Hoerner has a section on trains in his book,"Aerodynamic Drag." I'll dig it out and post that,but I think Bicycle Bob and Big Dave have covered the fundamentals of it.Next to water transport,the train is the most efficient form of transport even as imperfect as it is.

I love traveling on trains, so much better than the road. Toot toot!

Actually the prime mover (the diesel engine) in a modern locomotive is massive, not just large. For an example, the old EMD 567 prime mover was so named because each cylinder was 567 cu.in.!! Even an older inline 6 from, let's say, an old Alco is massive. Also, the main generator is much smaller compared to the prime mover, not larger.

People may think that the main generator charges batteries for powering the traction motors, that is incorrect. Locomotives do have a bank of batteries, but mainly for ancillary uses and of course for starting the prime mover. The batteries have nothing to do with powering the traction motors; all power comes from the main generator. GE does have a hybrid loco in the works that uses energy dissipated from braking (from the dynamic brakes), and uses it to power the motors on-demand, giving the engineer about 2000 h.p. for traction when necessary.

You seem to be implying that some axles are un-powered. ANY modern locomotive has all axles powered (i.e. one traction motor for each axle). 6 axles = 6 motors.

And here's why I hate that "commercial"...One single coal car has a loaded weight of 110 tons (as per wikianswers, although I did find another source that specified "120 ton coal cars" so it does seem plausible), which means when you see a loaded coal train with over 200 cars (I used to count the cars when I was a kid since there's not much else to do in a really small town), they're not getting 400+mpg.
1 ton = 400mpg
110ton = 3.64mpg
22,000ton = 0.018mpg
Still more efficient than a semi, but I just hate when people so obviously lie with statistics, even when they're telling the truth.

Volones you bring up something interesting....
So there's a coal mine in Healy, AK. It's about 400 rail miles to Anchorage, AK. I normally will see 50 coal cars behind 3 engines. So taking the 1T/1 gal for 400 miles,

50 cars*110T=5500T
5500T/xT *1T/1 gal = 5500 gal
400 miles/5500gal = 0.07273 m/g

That's terrible if you ask me. But that's only if you look at general fuel consumption. Specific fuel consumption...
My car: 1.5T, 32mpg. over 400 miles that's 12.5gal.
12.5gal/1.5T = 8.333 gallons to move 1 Ton. Not so impressive to the 1 gallon per 1 Ton.

I need at least 266mpg to match the train's efficiency at moving mass. The Loremo comes close at 180mpg, and the VW sausage thing (can't remember the name) can do it at 261mpg. I personally want a Loremo.

Not arguing, just illustrating for all to see how efficient trains are despite the poor aerodynamics.

almightybmw,
I fully agree that a train is still more efficient at transporting huge loads over long distances. what I don't like is the little blurb they put on NPR saying that the train can move 1 ton 400 miles on a single tank of fuel, when in reality no trains ever carry only 1 ton of anything. The cars weigh more than that empty. And yes, I'm arguing semantics here, I'm fully aware of that. :D

Vol
BTW, I was too lazy to compute the efficiency of an auto in moving 1 ton, thanks for doing that it's pretty eye opening.

Just remember, they're specifying per ton of freight. Your car is not hauling 1.5T of freight at 32 mpg.

That's not what they say. They say, "move a ton of freight 436 miles on a gallon of fuel."

FactCheck.org: Can a freight train really move a ton of freight 436 miles on a gallon of fuel?

Wow, and that number even includes partial cars, empty cars and switchers in the yards. Excellent find.

On top of that, it'd be fairly simple (technically) to electrify any given stretch of track, so that trains potentially would need not use any fossil fuel at all.

Can't cite a source, but some time in the last year or so - on the Discovery Channel or some such - I saw a segment on computer controlled engines & switches in switching yards. The engines propelled groups of loaded cars up to X.yz mph (Pulse) then release them and the car/cars would roll (Glide) up to 1/2 mile??? through a series of computer actuated switches to arrive with just enough force to auto-connect to a series of cars being assemble on a siding.

A loaded 100 ton car (gross weight up to 140 tons) at 1 MPH will coast for five miles on flat track.

BTW, railroad rolling stock is usually loaded 70,000 lb/axle. A four-axle car could weigh as much as 140 tons gross. All US freight locomotives have a traction motor for every axle.

Flat yards at night are often deadly for the unaware. That car is coasting along nearly silently. Switch yards work 24/7. This is why railroad detectives ("special agents") are very vigorous about trespassers.

Electrifying the mainlines is a simple but expensive proposition. It is old tech, well proven and available readily if not exactly off-the-shelf. Figure about $5 million per mile. Another $2 million per mile for the retrofit of electrical power transmission. About 32,000 miles of electrified mainline track would allow access to non-oil energy for 98% of railroads' energy needs. Figure that reduces the railroads quarter million barrel per day fuel appetite by 98%, but where do you get all that electricity?

I think that the main reasons for diesel-electric drive are to avoid burning out a clutch on start-up, and to keep the whole train from jerking with each shift. The ballast is also handy for traction. Presumably, one could arrange for a separate mechanical drive for use at speed, with a burst of power from the inertia of the generator in lieu of a battery to power the electric motors during a shift on the mechanical transmission.

Why don't you check out the market for mechanical drives and see if you can find one bigger than 1300 HP? You won't find one. These are occasionally used on little 500 HP industrial switch locomotives but could never venture out on the mainline with the big dogs. No gear would stand the "buff" (fore-and-aft) pounding a train dishes out. Even in big mine haul trucks the standard is now diesel-electric.

Keep in mind on locomotives weight is not much of a limitation. Most locomotives use scrap iron and concrete to ballast them up to the commercial weight. So the weight of diesel-electric drive is no big deal.

Just curious, what does it look like after $7 mil/mile? Is it a third rail or overhead? Do the existing rails get retrofitted with more deliberate connections between the sections? Or do you have to lay a completely different track?

Don't forget reverse. Locomotives run at the same speed and efficiency in either direction.

You also get cool benefits like slugs, which are locomotives (usually obsolete models) with the prime mover removed (and often replaced with ballast) but the traction motors intact. The slug is attached to a regular locomotive, which can power its own electric motors, as well as those on the slug. They're used in switch yards and other situations where you need a lot of tractive effort, but not a lot of top speed.

Should be off-the-shelf, since a lot of European railroads are electric. I don't know about cost, but $5 million/mile seems way steep. It's basically just running an overhead power line along the track, and a quick search finds costs in the neighborhood of $50K/mile.

If the conversion calculator - Fuel Oil Equivalent @Barrel (US) Conversion - I found is correct, you could run the entire system with 18 1-GWatt nuclear plants. Maybe with less than half that number, since I think the calculator is using total energy in a barrel, and not considering the less than 50% efficient diesel engine. On top of that, you could recover some energy through regenerative braking.

It currently takes at least nine years of operation for a nuke to pay back the oil that has to go into producing and fueling it. As the ores are depleted, that goes up. We still don't know how many year's worth of oil it will take to keep the dead reactors and their waste away from the biosphere, but that's another expense the next generation won't be able to afford. Nukes are one of the least effective ways to save oil, and definitely the worst in terms of risk and deferred costs.

Some locos can use their electric motors as electrodynamic brakes.

Why do you people go on repeating nonsense like this? Do you think we're all unable to do simple arithmetic?

Building a nuclear plant takes no more material or energy that building any other construction of similar size, and is roughly comparable to building the 2000 or so 1-MWatt wind turbines that would be needed to generate the same amount of power. If you use construction cost as a proxy for energy input, here's a wind energy site How much do wind turbines cost? | Windustry which puts the cost of wind turbine construction at between $1.2-2.6 million per MWatt, in the same cost per MWatt ballpark as a nuclear plant.