Here are some locomotive consepts.
Most of you may already know this, If so, sorry for the rant...... If you watch coal burn, naturally aspirated, and correctly vented, you'll see a nice blue flame above it. This is not often seen on a steam engine unless its about to get its fire dumped. This Blue is the actually the oxygen burning up the coal AND coal gasses. The more modern steam engines use Steam, in the smoke box, to help create a "draft" in the firebox. This is why they do not need a tall smoke stack like old wood burners do. This extra "draft" makes large coal burn faster, but much less efficiently. Smaller chunks, closer together can help as it slows down combustion and still makes heat. In Western US, the Bituminous coal is already filthy and dusty and actually seems to burn up better with the extra draft . Starting a Steam engine with Anthracite and making that firebox super efficient would take at least 1 hour, then the calories it takes to boil water would make it necessary to add draft. Better draft control with emissions testing on board may help this "coal gas" and particulate "situation" . Firebox design hasnt been NOT really been gone into in half a Centry or so. Maybe a recirc Smoke gas chamber would be of interest. A guy named Paquin got a patent for this design for wood stoves ( late 70's? early 80's? )and Its been used in coal burning as well since. As most of us know, Coal is the Most powerful fuel on earth ( aside from nuclear) IT has the most calories per ton of Any fuel around 22.4 Million BTU per short ton. Burning it more efficiently in a steam engine should be looked into. That said, this current EPA is shutting down coal plants everywhere, One would think this could be overcome with some science and DESIRE.
BastaTim The firebox will be a coal burning gas producer to combat the efficiency problems inherited with steam locomotives.
The firebox will be a coal burning gas producer to combat the efficiency problems inherited with steam locomotives.
What say people on this forum about the effectiveness of "gas producer" coal combustion?
I read over David Wardale's Red Devil and Other Tales of the Age of Steam, and the main motivation for the GPCS (gas producer combustion system) is to reduce the carry over of carbon particles ("char" and "sparks" and "cinders") in a coal-burning lump-coal grate-fired locomotive. The idea is that if you can reduce the primary air in the coal bed, you will reduce the tendency of the fire to lift. With reduced primary air and a thick enough bed, you will get the chemical reaction to make combustible gas above the firebed, which will burn in contact with secondary air, introduced through an open fire door or through ports through the firebox.
Red Devil reads to me like a treatise in frustration of Wardale trying to get the GPCS to work up to its promise. By the end of the book, he is resigned to "pulverized coal" as being the only answer to getting complete combustion of coal fuel. But with PC (pulverized coal), you have the handling problems and explosion risk of handling PC on a locomotive, and not only that, all of the fly ash is sent up the stack. With lump-coal-on-grate, you stand a chance of at least keeping half the ash out of the atmosphere and into the ashpan.
Maybe burning coal to do anything is a lost cause, given the new EPA regs to try to take coal-fired power plants out of service. But there are a variety of combustion system besides PC that people have tried and indeed use, and GPCS is only one of them.
The one I find most intriguing is some form of "slag tap" combustion. The idea is that instead of trying to avoid the curse of clinker formation, you embrace it as a way of trapping the ash in the form that cools to a glassy rock, much easier to handle than powdery ash.
In fighting with GPCS (and his Chinese hosts), Wardale suggested that with the powdery Chinese coal and the way they were firing the QJ class, they may have been doing a kind of "slag tap" firing. Wardale speculated that the only way the crews were able to fire the coal they were getting without it all ending up out the stack is that they first wet it so it would stick together as it was pitched into the firebox, where it would stick to melted ash pooled in the firebed. In GPCS, he had to avoid slag at all cost so he wouldn't end up with a big piece of clinker filling up the firebox with the thicker firebed required. His GPCS tests were showing worse performance at very high firing rates, which was the opposite of what GPCS was supposed to do.
Wardale hints at it, he alludes to it, but he "did'nt want to go there" of using a pool of slag in the firebox as something to prevent coal loss. He worried that there was not a good way to control the amount of slag so your fire wouldn't clinker up. But if he weren't under that much time pressure, and a recurrent theme of Red Devil is that the "higher ups" had already "given up on steam" in South Africa and China when he was doing his work, given more time, he or someone could have studied what was happening in these fires to get something better.
Part of this is that he was under contract to "do GPCS" that his hosts thought was the magic solution to coal combusion and he didn't have the luxury of studying what they Chinese crews were actually doing to get the awful quality coal in China to generate any tractive effort. Maybe the way forward in China would have been to better understand what the crews were doing and improve upon it rather than conduct experiments in frustration trying to get GPCS to work with an unsuitable coal?
But again, Wardale's take is that the decision to end steam had already been made and what he accomplished, in the end, did not matter.
But post Red Devil, I see some Web sites chronicaling narrow-gauge operations claiming some success with GPCS. What do people know about this?
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
I had a similar idea for a 4-10-4 locomotive, but a 4 cylinder design with the cranks set at 120 degrees for smoother running and better balancing. Perhaps even a compound design? Would probably take some work to make it flexible enough to run at decent speeds and make it around curves, though. Blind drivers and lateral motion devices might make it work, though.
I was more a fan of oil firing, though. It seems to me it would be easier to implement one person operation with oil rather than coal firing.
I'd like to apologize, I was much more blunt last night than I intended.
I encourage you to post your ideas and thoughts, because they are good ones. I've learned a lot from others here asking questions to try to improve my designs (such as an extreme-drag-freight 2-8-10-6 of questionable usefulness), and was trying to help you. I hope I haven't scared you off.
BastaTimThank you I am mostly a reader of the forums and not a poster.
I trust we can change that -- dramatically!
No problem! This is probably the best place to put this. There is just a complex story associated with this thread.
My comments-
Santa Fe had 2-10-4s with 74" drivers. At the speeds that this would be allowed to run, (<80MPH) a four wheel front truck wouldn't be necessary. Also, where do you think this would have run? Fixed wheelbase on this would be very long, restricting use. I offer this as constructive criticism to help you improve your design.
NorthWestWelcome! (Interesting that this appears to be the original thread that spawned the others-and refuses to die.)
Welcome!
(Interesting that this appears to be the original thread that spawned the others-and refuses to die.)
Welcome aboard Basta Tim, don't recall seeing you here before.
And I LIKE the way you think!
Go look at the thread on Mallard speed records, there are pictures and more discussion.
See Doug Self's site for the low-down on all the motor locomotives.
19 1001 has four 90-degree V-2 motors, two each side, each driving one independent axle. Gottwaldt's book has some information Self doesn't. This was imho a better approach in principle to the problems with high-speed drive than Besler's, but YMMV.
W-1 was the Besler locomotive -- not a 4-8-4 but a 4-2'2'2'2-4. As mentioned, one of the motors was built and tested, and I'm trying to see what information on the project has survived in Besler's papers. Not mentioned so far: the boiler for this locomotive was built and finished, but was never actually used (diesels giving a better perception of what B&O needed by 1941).
The French approach has some interesting details, notably the attempt at conjugating the engines to make their rather amazing high-speed-slip proclivity less... I suspect the conjugated-throttles approach would not have worked completely in practice, but that's because I've modeled the situation in a different context.
Have fun over on Self's site -- he has done tthe work for us all.
RME
i would agree that better thermo would negate the need for a big firebox
ok what loco was 19 &1001 & B&O W-1. I NEVER HEARD OF ANY OF THESE
Not a 6-8-6; probably 4-8-4 (as wartime restrictions on metallurgy would not have applied, perhaps even during the Korean War period when 19 1001 was expediently scrapped... my guess would be that in the absence of road dieselization, the history of that locomotive would have been radically different, as would the Besler-motored B&O W-1.
The better argument might be 'when would you go for the big six-wheel trailer, a la Allegheny and Long-Compression (double-Belpaire) locomotives... vs. 4-wheel trailer with same lazy firing requirements and firebox size reduced through better thermo... vs. better engines with 2-wheel trailers (see Richard Leonard's exploration of late NYC Mohawk practice.)
But 6-wheel lead trucks... not required for any sensible design that takes account of length in design...
GOD you guys are making me dig out my trains{did we scrap steam to soon} issue but do you think a 6-8-6 would really have worked ??
Erik , that reverse turbine geared to assist the forward turbine seems "genius" 'cause it would keep the time of de-efficiency of the forward at a minimum. Yes, the reverse turbine also would be working at its most inefficient....
A booster (rods, pistons, cylinders designed for low speeds being carried along at 100 mph) might....might be over-stressed.
K4sPRR The biggest problem with the PRR turbine experiment was the drastic drop in boiler pressure when starting.
The biggest problem with the PRR turbine experiment was the drastic drop in boiler pressure when starting.
And the reason for that was that the steam flow for a given tractive effort was pretty much constant from zero MPH to about 70 MPH. At 70 MPH, the S-2 was more efficient than any other PRR steamer, but way less efficient at ow speeds. Putting it another way, the S-2 could develop close to starting tractive effort at 70 MPH.
One solution would have been a variable gear ratio between the turbine ad drive wheels. Another would have been modifying the reverse turbine gearing to allow the S-2 to run forward on the reverse turbine at low speeds. Applying a booster may have helped as well.
- Erik
Firelock76 "...Take this for what it's worth, but I've read that the "bugs" in N&W's "Jawn Henry" could probably have been worked out if the experiment continued. As it was, "Jawn Henry" really didn't do the job any better than a Y6b did, and at more than the cost of a Y6b. If other 'roads showed any interest in a steam turbo-electric N&W might have continued the developmental work with the eye on sales to other 'roads, thus lowering the production costs, but none did, so the project died. "Sic transit gloria mundi..." ..."
"...Take this for what it's worth, but I've read that the "bugs" in N&W's "Jawn Henry" could probably have been worked out if the experiment continued. As it was, "Jawn Henry" really didn't do the job any better than a Y6b did, and at more than the cost of a Y6b. If other 'roads showed any interest in a steam turbo-electric N&W might have continued the developmental work with the eye on sales to other 'roads, thus lowering the production costs, but none did, so the project died. "Sic transit gloria mundi..." ..."
For what it's worth, my understanding is that the T1 mileage numbers quoted in that Gardener article from the January 1979 Trains were suspect.
More information can be found on this thread: http://cs.trains.com/ctr/f/3/t/174956.aspx
Looking forward to reading Dave Stephenson's article on the T1 in the upcoming 'Steam Glory 3'.
--Reed
I think the hammer flow forces are something to contend with. I was out watching MILW 261 come past a few years ago, on welded rail good for 79 mph. You could hear the rail zinging with the rotation of the wheels, and could hear the hammer blow. My dad had his video camera on a nearby fence post, and it started shaking. I think it almost fell off. Diesel electrics with their rotary power application don't do that.
There was an article in Trains mag, January 1979 I think, about the first PRR E7s. It came time to true the wheels on the E-units, and the round house foreman was incredulous about the miles the E's had racked up. The T1s in his house had maybe a quarter of the miles, as they were in the shop most of the time.
Mike WSOR engineer | HO scale since 1988 | Visit our club www.WCGandyDancers.com
The biggest problem with the PRR turbine experiment was the drastic drop in boiler pressure when starting. As to a future advancement for passenger steam, the reconfiguration of the boiler would have been a must. The PRR manufactured a working scale model of the S2 to try and solve this problem, but unfortunately and like the Jawn Henry project, a lack of interest put the project to bed....forever.
Take this for what it's worth, but I've read that the "bugs" in N&W's "Jawn Henry" could probably have been worked out if the experiment continued. As it was, "Jawn Henry" really didn't do the job any better than a Y6b did, and at more than the cost of a Y6b. If other 'roads showed any interest in a steam turbo-electric N&W might have continued the developmental work with the eye on sales to other 'roads, thus lowering the production costs, but none did, so the project died. "Sic transit gloria mundi..."
Paul, I too had wondered about water tubes over the other. I'm not an engineer, but it seems to me that heating smaller quantities 'as needed', or on demand, is a better way to improve thermal efficiency. But, being less than a dilettante here, I left it out of my musings above.
If exhaust draft up a stack is problematic, then don't use it. Blowers work well, and can always be improved, or perhaps ducted works routing exhaust steam, or even condensing systems, are the way to go. Exhaust steam could be routed via a nozzle facing rearwards in a safe, if noisy, place to add a wee bit of jet-like thrust. Or, just in two directions, sideways on either side of the boiler if it must be vented. Just not so that it results in massive amounts of ambient-temp air rushing up through the grates upon start-up. I do understand that you don't want to hamper the escaping used steam, or cause undue backpressures that end up defeating the power of the turbine.
Perhaps, and I hesitate to even 'go there', a single lower chassis cylinder to help lift the train. Boosters helped in earlier times. If the turbine can be held back and spooled up after 15 mph, maybe that would work.
Would anyone who knows take the time to do a micro-mini layman's explanation of the benefits and caveats between poppet, reed, and rotary valves?
Crandell
Back to the topic at hand of a better steam locomotive . . .
There were advanced steam locomotives regarded as "failures", but they had features on them that may have been worth keeping.
The C&O turbine-electrics were epic failures if one is to believe the press on them -- their efficiency was less than an equivalent rod-driven steam locomotive, and they couldn't get one to complete a trip without breaking down. I don't know if the one-of Jawn Henry was all that bad, but I am told there were problems with water and coal dust getting into the electrics, of the turbine unit getting knocked out by a hard coupling.
But both of those locomotives were coal-fired cab forward, having the coal bunker up front, but shaped to let the driver and fireman see out towards the front. Garrets also had separate coal bunker from water tender, and run in reverse, they were also cab-forward with the coal bunker up front. I am thinking that the idea of a coal-fired cab forward or a bi-directional coal-fired locomotive is pretty much proven by those experiments.
The Pennsy S2 steam-turbine mechanical drive was not regarded as entirely successful, but what people say about that locomotive varies. Some say it was too heavy on steam at anything less than 100 MPH, but others say it used the variable steam nozzle arrangement that the British tried on a somewhat smaller steam turbine that was regarded as being at least as efficient as an equivalent piston steam locomotive. On the other hand, some write that the S2 was plagued with firebox staybolt failures, and that came from starting from a dead stop requiring a great drawdown of steam that thermally shocked the firebox, but I never heard that as a problem with the British steam turbine.
But the mechanical drive arrangement was considered successful unless people know otherwise, that of use siderods but coupling into one of the wheels with a jackshaft (maybe on the British steam turbine, definitely on a Swedish steam turbine I have seen on a You-Tube video) or a quill drive (electric locomotive tech used on the S2 steam turbin) was a success. Maybe you could have a geared, high speed, thermally efficient "Uniflow" piston engine coupled to the wheels with that kind of mechanical drive. You have siderods but not a mainrod with its difficult-to-balance forces.
The other thing is, what was so wrong with a 4-8-4 Northern type? Did those things really pound up the tracks with "hammer blow" forces, or is that a slander ginned up the the Diesel sales people, where Diesels pounded up the track with their nose-suspended traction motors?
Another shibboleth of steam power is that the stay-bolted fire-tube boiler is the be all and end all of boiler design on a locomotive, and water tube boilers were "all failures." The Jawn Henry may have had its problems, but I never heard that its high pressure (600 PSI) wateer tube boiler was one of them.
What if you combined a coal-bunker-in-front cab forward or bi-directional steam locomotive with the Jawn Henry water tube boiler, with best practices of a high-speed poppet valve geared drive Uniflow piston steam engine with jackshaft/quill drive into siderod drivers after the S2/British/Swedish turbines? In other words, keep the things that worked on the various "experiments"?
Paul Milenkovic stated, "The focus is wrong, the focus is on building a better locomotive whereas the focus needs to be on building a train operations system, concentrating on everything from crew training to maintenance and service facilities to how you keep those engines on the road and get economic return from them."
This says it all. Railroading as a profit making venture, is a system of locomotives, cars, tracks, infrastructure, operations, etc. All parts must work together. N&W was probably the best proponent of this idea in late steam. They added a-tanks to eliminate intermediate water stops (can you imagine how expensive it is to stop and restart a 15,000-ton train?), using larger cars (70-ton instead of 50-ton), curve lubricators (yep, even in the early 1950's). When they finally dieselized, a lot of the more modern ideas were already in place.
Getting back to the topic of the thread, can you imagine a poppet valve equipped N&W J? There are indications that N&W and Franklin were thinking about it...
Our community is FREE to join. To participate you must either login or register for an account.