Paul Milenkovic Where is "Juniatha" when we need her, anyway?
Where is "Juniatha" when we need her, anyway?
I was wondering the same thing. A compound duplex drive would be more her liking than the GE turbomotive.
Paul MilenkovicYou mean "Verbindungexpansionkonjugiertduplexantriebdampflokomotive"?
Niemals!
"Verbindung" has the sense of lashed up tight, or chemical bonding; a compound locomotive is just "Verbundlokomotive" (with the 'dampf' implied). Much as it spoils the comic sense, a 'more correct' term might be something like 'Verbundlokomotive mit Withuhn-gekonjugiert-Duplexantrieb' ... which puts the elements in a better rhetorical order if you have to have them all in there at once.
I agree that Juniatha is the best one to decide on a correct German expression, and I hope she will drop in, however briefly, with her version.
You mean "Verbindungexpansionkonjugiertduplexantriebdampflokomotive"?
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
CandOforprogress2"compound-expansion conjugated duplex drive" Chew on that for a moment
What he meant is really very simple, and is contained in the original American Coal Enterprises patent for the ACE 3000.
A 'duplex' locomotive is one that has two separate 'engines' in a rigid frame. A conjugated duplex connects those two engines so that one of them cannot slip uncontrolled by itself. Bill Withuhn developed an approach to do this on an eight-coupled locomotive, using a pair of inside rods phased to give both equal balance and equivalent cylinder thrust at all points in a cycle; this was described in an issue of Trains in the early '70s, and was the system intended for use on the ACE3000, although construction of a practical example involved far more than the patent drawings indicated!
Another feature of the ACE3000 was that it was a compound, which performed expansion of high-pressure superheated steam in multiple stages for better thermodynamic efficiency, then used the LP exhaust through a turbine to drive some of the auxiliaries and the draft fan (all this will be much clearer if you are looking at the patent diagrams). This also improved -- whether 'greatly' or not is up to you -- the ability of the design to condense a meaningful proportion of the exhaust back to feedwater for the Rankine cycle.
Hence that somewhat Twain-German-like term. Perhaps it would have been better broken into separate sentences, or presented a bit less 'saltily'.
"compound-expansion conjugated duplex drive" Chew on that for a moment
M636CThe Victorian Railways were keen to use local supplies of brown coal and had tried pulverised coal firing earlier in the 1920s. The system they used was called "Fuller-Lehigh" which sounds a lot less German than "Studiengesellschaft" and which I thought was in fact American. Has anyone details of this system?
Here's a start.
My references to the GE Turbomotive (both of which are in German) suggest that the big problem was not getting it to run, but the fact that the fuel consumption was unacceptably high. This was a common result in the adoption of higher pressures and techniques associated with power stations, in locomotives....
I belive that some of this effect was simply from scale factors, partly because the losses were proportionally higher with a much smaller plant.
I'm surprised at references to the Victorian Railways use of pulverised coal. Surely there are more extensive references of the system in use in Germany where it was used much more extensively...
The Victorian Railways were keen to use local supplies of brown coal and had tried pulverised coal firing earlier in the 1920s. The system they used was called "Fuller-Lehigh" which sounds a lot less German than "Studiengesellschaft" and which I thought was in fact American. Has anyone details of this system?
M636C
Paul MilenkovicGetting the UP coal turbine to work is not what I have in mind because yes, the fly ash, even from, no, especially from finely ground coal will wreck the gas turbine.
Looks as if after the BCR development effort had collapsed (largely because railroads stopped funding the self-promoting effort after it should logically have become a locomotive-builder or perhaps government-supported research effort) but before the UP coal-turbine experiments, the "tube" development reached a point at which a couple of the usual-suspects inventors thought it was marketable under the name "Dunlab tubes" (see patent 2869677). I think this might have been part of why UP went to the trouble of developing their 'new' coal turbine in the '60s.
There is an interesting article on the general topic of erosion in turbines here with the bibliography in particular providing a very large number of interesting period references...
I was thinking to pulverize the coal and burn it in place of oil in the GE Turbomotive boiler.
Some of the Yellott combustor patent information indicated that his approach for burning the coal would give you better fine control ("almost that for a gasoline engine") of the sort that would be needed for fire control on one of these boilers. Look on the steam-automobile side on what was needed for firing something like a tapered monotube.
I'd be very concerned with the effect of ash abrasion from PC firing through a comparatively small coiled-tube configuration -- you do not have the very long and partially vertical gas path of a typical powerplant boiler burning that fuel.
David Wardale in Red Devil expresses doubt about the Porta-style Gas Producer Combusion System (what ACE was going to use) and interest in pulverized coal. His vision of pulverized coal is that you pulverize it right at the end of the stoker feed just before blasting it into the firebox. Isn't that what the UP coal turbine was doing, pulverizing at the point of feed rather than storing pre-pulverized (and explosive) coal in the tender, which I think the Australian brown coal steam locomotive was doing?
I had the distinct impression that the pulverizing on 8080 was done on a separate unit from the turbine, and the PC and air was blown through (substantial) hoses from one unit to the other (there is a picture on the Web showing these, annotated as such)
The problems with pulverizing the fuel while on the road are many, and the difficulties with pulverizing coal effectively 'at the stoker table' might be interesting to consider. Something I thought about was a 'hybrid' approach like that of early oil firing, where part of the stoker feed is made onto grates, in an approximation of normal practice, and then pulverized coal is blown over this for some of the actual combustion gas plume.
Another possibility is coal-water or perhaps coal-fuel oil or maybe coal-oil-water (with a lot of detergent?) slurry? With equal parts water and powdered coal, yes, you sacrifice 10% in thermal efficiency right-off-the-top when that amount of water is turned into steam inside the firebox, but the carbon carryover losses are higher than that, even with GPCS.
The actual use of slurry fuel in locomotives is constrained by the available "packaging" dimensions of typical cost-effective boiler systems. It turned out for the Donlee boiler that the amount of 'water' did not matter if you can recover the heat in the water, particularly the latent heat of vaporization, in heat exchangers further down, this being particularly noted for the NOx steam injection but of course applying also to slurry water. I have to wonder, though, that with all the interest in slurry fuel (or, as you note, detergent dispersion of oil in slurry) I have seen no effective prototype, even at automobile scale.
Wardale's thinking is that the only hope of some kind of multiple-unit operation is some kind of powdered coal -- even with stoker feeding, the GPCS needed too much tending from a properly trained fireman to contemplate automatic operation.
It is arguable that GPCS can be reliably developed for automatic firing -- my father thinks it technically could, but the required system even with OTS computer components and full 'academic' support developing the software and artificial intelligence would not be cost-effective with diesels. That's really the criterion that shuts the idea down for me.
I tend to agree with those who think unattended multiple-unit large steam boilers are ridiculous even to consider; the very first significant accident would be a lawyer's paradise. The situation is a bit too different from stationary practice (where automatic firing is more sensible in a number of respects). Diesels 'do' MU almost inherently, and don't have as much risk of very high energy release on failure.
To me the only practical system for MUed steam, other than some version of fuidized-bed as in the locomotive designs from the '80s, is the chain grate as applied to the TE-1, which essentially ran 'unattended' most of the time in that locomotive by necessity. One critical thing here is that the grate has to be made periodically reversing, and careful design to keep the fire from burning back into the feed coal has to be designed in.
Getting the UP coal turbine to work is not what I have in mind because yes, the fly ash, even from, no, especially from finely ground coal will wreck the gas turbine.
Quoting Wizlish: "There isn't enough room for all the Hilsch tubes or whatever they were,...." I don't know what were used, but I know that a Hilsch tube is so made that it separates hot air and cold air, and sends the hot air out one port and cold air out the other. Clerk (Clark) Maxwell posited that a demon (Maxwells's demon) sits at the junction and kicks the cold molecules out one way and the hot molecules out the other way. Perhaps these devices used a different sort of demon?
About fifty or so years ago, someone decided that car airconditioners should be made with Hilsch tubes in them--quick cooling or quick heating according to the need.
Johnny
I like this discussion already, and I'd bet my father would like it even more.
We don't know enough about the 'Turbomotive' because many of the severe kinks were only ironed out during wartime, and the locomotive was retired and scrapped before any of the (supposedly many) detail fixes were recorded.
The principal problem, of course, is that the Turbomotive used high-pressure flash boilers that implicitly required fairly refined liquid fuel. Firing control was fairly 'tetchy', and the general capital requirements were really high for a locomotive that only produced 2500 hp per unit, with DC traction motor limitations, and had a GG1-like weight issue and similar number of undriven axles. One sticking point was that the feedwater had to be of suitable quality for the high pressure, and this specifically involves silica carryover.
On the 'flip side', the exhaust plenum arrangements in particular were well-designed for the turbine size, and it is possible that some of the condenser issues (so damaging to the ACE3000 concept) could have been handled even for the hot climate a UP locomotive might be expected to traverse. However, scaling this up to 'meaningful' power size today runs squarely into difficulties that are better addressed with non-external-combustion power.*
The TE-1 as it was built was a thing that probably shouldn't have been, the result of steam people finding the wrong things to compete against diesels with. Remember that, even as it struggled to compete with locomotives a third its cost, it had a practical traction-motor life -- and this with Westinghouse hexapoles! -- measured in a small number of years. Compare its length, complexity and cost with, say, a modern GE or EMD 4400hp diesel-electric; at least one attempt was made to scale the locomotive to 6000hp, but the boiler and bunker considerations became difficult to package. (I ignore the repeated and severe generator problems as being a stupid Westinghouse quality problem, and perhaps conversion to a full synthesized-AC drive on the twelve axles would have solved the incidental issues, but you're still left with the two serious ash problems, and the very complex automatic boiler controls that have to work reliably under severe conditions).
The ACE3000 is lamentably underpowered even for a single-unit locomotive of that cost and complexity, and the practical implementation of Withuhn conjugated duplex in a stiff enough 'engine bed' was never carefully discussed (look at the drawing of the drive in the patent description and tell me how the bearings for the inside-cranked axles were going to be provided -- and remember these were the mains.
'Mine-run' coal is never the answer to anything practical, let alone something that is supposed to run unattended in a world where the EPA exists. That is especially true when it is in relatively small sealed containers that will not fit if damaged in some highly probable ways. The condensing and draft arrangements had some very interesting potential common-mode failures, and in fact a great many potential failures would either leave the locomotive dead on the road or derate it to the point it would compromise train handling. This is not to say there isn't something that couldn't be done with some of the ACE stuff, but you'd be much better advised to look at the ACE6000 2-10-2, or perhaps an adaptation of Porta's 2-10-0 with 'tender steering' of the rear frame, if you want a model to start working on a practical locomotive.
All the coal turbines founder on a fundamental point: how fast you have to move the required mass of fuel through the combustor and separate out ALL the ash with a minimum of gas-kinetics compromise going into the turbine. There isn't enough room for all the Hilsch tubes or whatever they were, and the clever methods of grinding and then impact-triturating the coal fuel turned out not to work quite well enough. In any case don't bother: the fly ash problems from any workable coal turbine will eat you alive. The UP 8080 project was the final coffin nail for anyone who thinks the idea is bright enough to revive. Now, if you want to have fun with this idea, there *was* a practical coal-turbine of sorts -- it was put into a couple of drivable Eldorados, of all things! -- which burned the moral equivalent of copier toner from a bin kept agitated with a vibrator. You're welcome to scale this to locomotive size using SRC, but I think you'll have a hard time selling it as a practical proposition (and much of the 'romance of the rails' is notably absent from any such locomotive or the smells and sounds likely associated with keeping it running...)
... and the ash problem carries over (no pun intended) directly into any practical system involving pulverized coal.
Now, there have been some pretty good attempts at PC firing, notably the StUG system as tried in Australia in the '50s. But they all totter and fall on two points: reliable flameholding, and the fly ash handling problems. That is, if you ignore the real, fundamental problem with PC, which is that for any suitable fuel it is a matter of when, not if, someone forgets something and the fuel reaches critical mixture in suspension and goes off like a bomb. Just takes once and any 'big savings' are gone even before the lawyers start to flap in...
Now, if you want a practical steam locomotive, I'd propose three general sorts of design:
1. Mechanical design with turbines and Bowes drive/magnetorheological and Maybach clutches. As tried with the V1 turbine; scale it to whatever boiler size you have in mind, and you can condense or not (or even use Holcroft-Anderson) if you need better water rate.
2. Some modern version of GTCC, using a workable approximation of ALPS or the Jet Train chassis in Pueblo with steam bottoming running the 'reverse' rotor of the MegaGen the other way for a bit more power recovery...
3. Adaptation of the steam generator and engine ideas of Cyclone Power (Harry Schoell's company) in fairly massive parallel, perhaps with renewable fuel. This might gainfully be done as a kind of 'dual power' locomotive with a relatively small 'pony diesel' for various functions not well suited to ultrasupercritical steam directly, a bit like the PR43 used its C18.
. . . with the Jawn Henry and with the UP coal-dust gas turbine . . .
The ACE 3000?
The GE "Turbomotive" steam turbine-electric demonstrated a high-pressure flash boiler, condensing and multiple-unit control. The Jawn Henry demonstrated a water-tube boiler with a travelling-grate stoker. The UP coal gas turbine demonstrated pulverized coal combustion.
The turbine-electric drive, especially coal dust or water getting in the electrical gear, was said to be the shortcoming of Jawn Henry rather than the novel boiler and stoker. Burning pulverized coal feeding a gas turbine was said to be the downfall of the UP coal turbine rather than burning pulverized coal.
The ACE 3000 aimed to avoid the problems of turbine-electric drive by using a compound-expansion conjugated duplex drive, but skepticism regarding condensing and serious skepticism regarding automating coal combustion contributed to the funding drying up before anything could be built.
But suppose, just suppose, that the ACE team mixed-and-matched these prior designs, such as combining the boiler and condenser from the Turbomotive with the pulverized coal combuster from the UP coal turbine with one of those locomotives from France with the conjugated duplex drive? I am not saying they could have gotten the actual hardware in every case, but there must have been blue prints to build their own?
My point is the components for an ACE-3000 could be cribbed from "failed experimental steam", with the components not being the reasons these experiments failed?
Do you think an enthusiast group could raise enough money to do something along the lines of the new-built Tornado, the bio-coal 4-6-4 project in Minnesota, or the people building a new T-1? Could something like this be built subscale in "zoo gauge" by a wealthy individual?
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