This might shock you – it did me! – but the French tested a steam-electric locomotive in 1897. No, I haven’t transposed the digits – that’s 1897!! Try googling “Heilmann locomotive” …
Craig
Hi Craig
The Heilmann locomotive - yes I had read about it in an early number of the LokMagazin ( ger for loco magazine ) of a collection lot of well over 100 numbers I had bought in an antiquarian bookshop in Berlin in 1992 . I remember having to urge the storekeeper to put them aside for me since as a teenager of sixteen I sure didn’t have the money right with me and he was so sceptical if I would ever come back and buy them as I said .
Edited paragraph with extra information :
The loco concept put up by Jacques Heilmann was remarkably advanced with a frame supporting boiler , cross mounted two cylinder compound engine plus generator unit , cab and supplies , resting on two eight wheel power trucks , all axles driven by electric motors . As with later diesel-electrics the locomotive showed a great potential in starting and hill climbing , the article described it as quite successful and two more powerful locomotives were built with an early ‘Jules Verne’ or ‘Nautilus’ type of streamlining while on the prototype the engine unit had been mounted pretty much on open deck with the front shaped in quite an earnest looking wooden wedge .
The first test locomotive of 1892 had Lentz boiler of 180 psi , 1000 A / 400 V generator , 44 kW electric motors , all electrical equipment came from BBC ; tests were run on the St.Germain-Ouest to St.Germain Grande Ceinture railway of the Ouest ( Western Railway Co.)
The two locomotives built for the same railway company by Cail & Co , Demain , in 1896 as # 8001 and 8002 intended for passenger service on the Paris - Trouville and Paris - Rouen mainlines were 60.7 feet between bumpers, had a boiler with a Belpaire firebox , no
I can’t say I’m not enjoying this.
Apart from the burner problems with the Triplex, I also have understood that as the tender-cum-engine supplied water to the boiler, it tended to get lighter, and that affected adhesion. So, while the burner couldn’t really heat the water to provide the steam needed, when it was drawn down by the injectors, the water volume lightened in the tender/engine and made for a lightweight set of drivers.
Okay, so boosters are not ideal, and we have agreed we want unsprung and reciprocating masses minimized? Yes? Then we need a drive mechanism that rotates around an axle that is geared or fluid-coupled to the drive axles. Or a jet engine. Or electric. Cylinders with large reciprocating and valved masses, and connecting rods, are out.
Could we have a burner array that runs along the belly of a boiler, thus doing without the problems of a crownsheet, stays, and so on? We would still need a pretty stiff blower to help the draught up the vertical flues, and we would need a collector system for hot gases to get them to the flue exit, or stack, probably centered on the boiler. The flue pipes would be ‘starred’ in cross section, with fins running along their outsides parallel to the main axis of the flues for maximum heat transfer. Same for the collector. This system, if it can be built and controlled effectively, would supply heat to the boiler at about twice the rate of a conventional firebox arrangement. To help wick heat away from the bottom of the boiler, to minimize heat gradient stresses, the plating or inner liners of the boiler would need to be designed and built of the correct materials, and probably also have ridging or fins to increase heat transfer.
Some of you probably are thinking to yourselves that it’s a good thing some people don’t design steam locomotives. [8-|]
Crandell
Answer me this.
The Garratt seems to be a good design for getting good steaming and a lot of powered wheels. There were even plans (suggestions? pipe dreams?) for “double Garratts” – essentially a Mallet’s double sets of engines and drivers on each of the front and back ends fo the Garratt boiler.
A Garratt may have been able to pull this off – the big-fat-short boiler with enormous firebox and ashpan suggests that the Garratt’s steam-raising ability is without peer.
But . . . even on the “normal” Garratt, how did they get live steam and exhaust steam to and from the two bogies, without a lot of losses from the flexible connections, without thermal and pressure-drop losses in the long pipes involved? Where did those steam pipes even go? Even on a Mallet or simple-expansion articulated you can see those pipe runs to the front engine and driver set, but you don’t even see any large-bore steam pipes on the pictures of Garratts I have seen.
Hi Crandell
At this point I have to admit , in my ‘walk on the wild side’ type of private (pre-)engineering me too I had put up a concept of a Triplex , and just because of this very point - supplies vanishing & and tender adhesion mass alleviating - I had carried it just one step further , figuring if you can have two axles coupled in front of the main driver you could as well have the same on the back side of it - makes for a 10 coupled unit .
You’d think I configured it to be a 2-8-8+10-2 ?
Naw-naw-naw , sir - not with my way of thinking ! Ten coupled once introduced , I immediately thought “Why not have it on all the three engine units ?” Mind my previous mentioning preference for identical sets throughout . So I ended up with a 2-10-10+10-2 - all simple expansion . Sure enough there was that vanishing adhesion mass problem again .
Ah , but not with young June : “Let’s fit individual throttles , one for each engine unit , three in a bunch to be grabbed together as the throttle levers in a BUFF yet individually adjustable to make the most of adhesion .” The throttles were to have on spot hydraulic power operation so moving the levers didn’t take but light effort as you effectively just opened the power valves of hydraulic lines . The idea was , you would start opening the combined levers as one yet just to an extent sure to be supported by adhesion and then as the engine began to move you’d open up further on the second and first engine units , leaving the tender unit as set or just cautiously opening up depending on degree of supplies spent . Since the locomotive was purely intended as a ramp pusher , tender capacity wasn’t all that large anyways while no attempt at low empty tender mass was to be made .
Arrangement of live and exhaust steam piping was a po
You or some others could always build it in “zoo gauge” (12" narrow gauge or whatever is popular for amusement parks and zoos featuring steam railroad lines traversing the ground).
If some airplane hobbyists “from Texas” (folks with gobs of money to spend on eccentric and expensive hobbies seem to hail “from Texas”) could perform aerial flyovers of Oshkosh, Wisconsin U.S.A. in a MiG 21 (before the fall of the Wall and before the ouster of Gorbachev, no less), there are people who would have the money, skills, and opportunity to build Juniatha’s Triplex Dream Locomotive (Traum Lokomotiv?).
Hi Paul
Model building :
Thanx for the proposition , Paul , yet quite certainly I’ll never have time to realize a running steam powered model - nice idea though and I would supply drawings and additional help to someone who would indulge in building one .
Pictures of Garratts with live steam pipes along side of frame
(4-8-2) - (2-8-4) BGB (Beyer Garratt Belpaire) - see pipe emerging from smokebox as usual and going along bridge frame towards rear cylinder
http://www.members.optusnet.com.au/~harburg/locos/DeGarratt-17-aw.jpg
(4-6-2) - (2-6-4) - see live steam pipe monted above bridge frame beam
http://users.powernet.co.uk/hamilton/
(4-8-2) - (2-8-4) - see live steam pipe running along boiler side with exhaust steam pipe returning along outside of bridge frame beam
http://www.flickr.com/photos/sierpinskia/5916460832/
(4-8-2) - (2-8-4) - see live steam pipe running along outside of bridge frame beam ;
http://www.scotlandforvisitors.co.uk/garrett.jpg
(4-6-2) - (2-6-4) - Narrow diameter live steam pipe with at best ‘T-shirt’ type of insulation running along outside of bridge frame beam . Clearly , the PLM Algerigue 231-132 series passenger Garratt with Cossart poppet valve gear was a locomotive intended for permanently warm Southern Mediterranean / North African climate without severities of Continental European winters .
On the Garratts, what sort of (flexible?) steam pipe connections did they have at the articulation points?
what sort of (flexible?) steam pipe connections <<
Principally same variety as in Mallets …
| = J = |
While I realize that the reference to 12" gauge was just an example of a park train size (most are 24" gauge these days), I still had to smile at the thought of Juniatha’s 2-10-10+10-2 built as a 12" gauge locomotive… that would be a monster! Aside from the time and money it would take to build it, I can only think of a single 12" gauge railroad in the US where it would be able to run. Most 12" tracks (mine included) are populated by relatively puny 4-4-0’s, with tight curves to match. The normal hobby gauges (7+ inches) might be a better choice - there are a lot more of those tracks available - and quite a few articulateds in the 7.5" gauge realm, including at least one Erie Triplex:
http://www.youtube.com/watch?v=7JemEIAnww8
Nonetheless, I would heartily encourage anyone in who is interested in increasing the efficiency of steam locomotives to get involved in live steam. It would certainly be a more economical way to experiment as opposed to full size steam, and it would be very interesting to see the various ideas put forth in this thread actually operating, albeit in a smaller size.
I thoroughly enjoy these types of threads, even if I’m not an active participant. Always fun to read Juniatha’s posts! Thanks to all for the interesting reading…
- James
WOW! This is SOME thread we got goin’ on here! Excuse me while I put my eyeballs back in the sockets and reach for the Seagrams to ballast myself a bit.
Here is an idea which has been kicking around in my head for some years, and maybe someone can expand on it or tell me why it wouldn’t work: Why not pressurize the whole firebox and flue system to maybe two or three atmospheres? This would increase the intensity of the combustion, and the higher density of the combustion gases would cause a more efficient transfer of heat through the firebox walls and flues. The pressure at the smokebox would be used drive a turbo to compress the air for combustion, providing a sort of feedback similar to that provided by the exhaust steam in conventional locomotives. Of course, this would be a bit tricky to do on a coal-burner, so it would almost have to be done on an oil-burner.
It would seem that to hold back-pressure in the firebox, you would have to severely restrict the exhaust outlet. This would also increase the partial pressure of the exhaust gasses, which I can’t imagine would help with efficient combustion.
A blower/turbo in an internal combution engine works because valves open and close which permit the charged or supercharged air from escaping as the piston compresses it further. There is no conceivable mechanism which would allow the same thing to happen in a firebox. You must allow the hot gases to flow readily through the flue pipes in a conventional steam locomotive, but in order to supercharge the firebox, you’d either have to close the flues in the rear flue-sheet or at the far end, at the smoke box. Otherwise, everything just goes faster, and more of it, if you blow into the firebox to raise pressure.
Improved flue design and firing might make a difference, and even the use of improved blowers in the smokebox, although the latter were used routinely right from the start. Except that they drew firebox gases through the flues, and didn’t force it through them.
Crandell
Why not pressurize the whole firebox and flue system to maybe two or three atmospheres? <<
Paul ,
there is something in it , for sure , as to intensify heat transfer - and it could also allow for smaller tubes and flues sections in relation to length between tube plates .
It would ask for some thinking about details with oil-firing but present no major problem in that combination .
I had come to a similar idea in order to solve the problem of rapid abrasion of blower blades with coal fired condensing locomotives ( uhm , steam locomotives , that is - g ) All those locomotives featured blowers in replace of ejector type of draughting and invariably mounted to the same position . My thought was , ok , if you have an exhaust steam turbine driving a blower why not put the blower to the other side , i e upstream combustion , to blow fresh air through the grate instead of sucking dirty combustion gases out of the smoke box . This would provide some degree of over-pressure above atmosphere , no ways as much as you mentioned , however it would make a difference in gas to wall heat transfer intensity .
With coal firing - that’s only where the problem of abrasion of blower blades was severe - that disposition would present one immediate problem : how to tighten ashpan and firebox feeding to prevent escaping of air and - more importantly - flames . Clearly , any detachable feed line , any type of fire doors inside cab were ruled out . While a stoker feed line with archimedes screw filled with coal could probably provide enough resistance for loss of gas flow to become negligible in view of boiler performance , escaping flames and hot gases would still present a very real risk of igniting coal before it had reached firebox . Again , this problem could turn out rather theoretical as long as feed was
Juniatha, I’m glad you didn’t think my idea was crazy. I think I started down this path years ago, after reading about the condensing locomotives in South Africa. (I think.) It seemed to make more sense to put the blowers at the input rather than at the exhaust, then it grew from there. The only way I could think of to make it work with coal would be to seal and pressurize the whole coal bunker and stoker, but that would complicate matters if manual intervention would be required (e.g. breaking up clumps). I wanted to include condensers in my plan for my dream locomotive, but the plans kept getting more complicated with so many heat exchangers and inter-coolers, that I was afraid I was approaching perpetual motion.
Now I’m intrigued about your power throttles next to the cylinders. Are you talking about replacing the conventional valves with valves controlled by a combination of, say, throttle-position, piston position, speed and other parameters, similar to the way modern car engines have computers controlling the mixture and ignition timing? It might provide a more economical use of steam.
Here is another crazy idea (I think I have too much idle time). How about something similar to a diesel cycle: eliminate the whole boiler, have cylinders with massive heads that are heated to a very high temperature and inject water against these heads which would vaporize instantly, providing thrust. Of course these would almost have to be single-acting pistons, as I think providing a seal for the piston rod at such a high temperature would be difficult.
It’s fun to think up things like this when you don’t have to contend with things like reality.
MidlandMike and selector:
While the exhaust back-pressure would be higher, the pressure of the air entering the firebox would be proportionally higher, so the flow would be essentially the same. The goal is to increase the density of the air, which would cause more intense combustion and greater mass to carry the heat and transfer it more efficiently through the firebox and flue walls. The part I sometimes wonder about is using the exhaust pressure to run the blower, as it seems a little like perpetual motion, but then a jet engine does a similar thing. The exhaust pressure could be used to run other auxillaries, and other means could be used to help provide the pressure.
Pressurized combustion in a boiler? I think that was tried and had a name – Velox boiler? Did it have success in any applications?
I’ll get to the power throttles – btw having decoded Porta’s ‘Waggoner’ throttle references – in a bit.
Forced (as opposed to induced) draft has been tried on locomotives, most notably in the Velox boiler. Principal technical issue is fuel feed; secondary issue is the incredible mess that results from any leak in the pressuretight casing (the amount of blankety-blank language from engineers on power-station boilers with pressurized firing can be frightful!)
Biggest thing about use of forced draft is that it’s only economically ‘optimal’ for long, sustained runs at high output. Rail service isn’t like that; you’re constantly varying steam demand even in general train-handling, and things go quickly out the window if you regularly take siding or experience slow orders. The armchair thermodynamicists never seem to grasp this point adequately.
A better case might be to use a small measure of variable forced draft in conjunction with a GPCS-style firing system (where the gas-tightness of the combustion spaces is required by the system). One thing here is that you would need proportionally larger radiant absorptive surface to take best advantage of this (although I grant you the situation isn’t as bad as methods that rely on increasing gas speed) Question is whether the relatively small gains in firing efficiency warrant the capital investment, training requirements, and so forth in general service, as well as the perhaps-severe problems if the added equipment or systems break down or their performance degrades ‘ungracefully’. (Hint: not likely in the early '50s, and even unlikely in the relay-logic era of the TE1)
You still need to maintain induced draft at the front end for a fairly wide variety of reasons – if you do this with a fan or blower, place it where the South Africans did, whether or not using the ‘turbine drive’ methods in the ACE 3000 patent. This simplifies the for
Come on, guys – where is everybody?
This is not all that wild. The basic Triplex idea can be ‘better’ than the original motor-tender-with-2-8-8-0-stability if you attend to some proportioning (and used some care at the joint under the cab): it might be thought of as one-and-a-half Y6s, with only the leading and trailing two-wheel trucks at the ends. Give that locomotive Chapelon-style proportional-IP injection (US jingoists, think of this as a more controllable version of the booster valve Louis Newton described) and there is no particular reason why, compound, it couldn’t be worked at normal 45-55mph freight speed. Principal issue for such a thing would be a tendency to pick the ‘leading’ driver flange of the rearmost engine, but if you were really concerned there are approaches that could be used to address this with minimal loss of potential adhesive weight. (And in case you start fretting about water and fuel mass on drivers, there are ways to address that too…)
Actually, if any engine were to remain eight-coupled, it would be the one at the ‘wrong’ end of the locomotive (no good practical way to use the exhaust even with GPCS steam injection; trouble with the longer rigid wheelbase; relative loss of usable TE, etc.) What you’d do would be put two ten-coupled engines up front, like the inf