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Sticks
2008-Aug-01, 08:39 AM
I saw this on my media sweep for work purposes

From BBC News Online (http://news.bbc.co.uk/1/hi/england/7536023.stm)


The first steam engine built to run on the UK mainline for almost 50 years is to make its trial run.

Tornado has been assembled by steam enthusiasts in Darlington in an 18-year project costing £3m.

The 72ft (22 metre) engine is based on the Peppercorn A1 locomotive, which British Railways withdrew from service in the 1960s.

The locomotive will be making its first public move under its own steam on Friday morning.

Once fully running and certified it will be used to haul charter trains operating on Network Rail.


To bring back steam we would need to bring back certain infrastructure items such as access to water

Given the rising cost of oil, would this make economic sense to return to the age of steam?

NEOWatcher
2008-Aug-01, 12:01 PM
Given the rising cost of oil, would this make economic sense to return to the age of steam?
No;
Even if the power efficiency and fuel cost can be lower than oil, you still have other major factors.
Maintenance is very expensive.
Liability is high.
Even if they are made cleaner, you will still have a major perception problem.

Even if you can overcome some of these issues, it will be as or more efficient to use electric. Especially since a lot of power is generated in much the same way.

Sticks
2008-Aug-01, 01:45 PM
IIRC when there was an oil embargo on South Africa in the days of apartied, because they had large coal reserves, they went back to using steam trains.

LotusExcelle
2008-Aug-01, 01:59 PM
Steam may in fact be coming back in a big way. There is already work being don eon the six-stroke engine which uses a steam phase to gain ungodly power on otherwise wasted heat.

Also steam turbines are really more efficient than steam piston engines - maybe something will come of that in the future. Then there is the Sterling.

Anyway... yeah.

danscope
2008-Aug-01, 03:42 PM
Steam enjoys flexibility in required fuel. And...there is NOT a lot of maintanance
owing to superior metalurgy. Look at marine boilers. They use fantastic pressures and work every day, years on end. Simple lower pressure boilers
for recip steam are a cake walk by comparison. When oil was 15 cents a gallon, no one cared. Now, we can do better. And we shall.
Best regards, Dan

aurora
2008-Aug-01, 03:45 PM
Aren't all nuclear plants using steam?

LotusExcelle
2008-Aug-01, 03:48 PM
Super gigantic steam turbines, yes.

NEOWatcher
2008-Aug-01, 04:35 PM
Steam may in fact be coming back in a big way.
Steam engines or steam driven or steam energy?

I guess my definition is narrow in context of the traditional return of steam locomotives. In other words, an open cycle method of converting heat directly to vehicle movement with steam as the medium.

Other than that, I do agree with many of the statements, although I see any future of that steam to be in the form of a hybrid. In other words, a steam device to run a generator that directly or indirectly powers a drive motor.

cjl
2008-Aug-01, 04:48 PM
I would also say that steam turbines are likely to be the way that any new steam powered devices extract the energy, rather than piston engines.

captain swoop
2008-Aug-01, 08:02 PM
The difference between a marine boiler and a boiler on a railway locomotive is size and vibration. A railway boiler has a far harder life than a marine boiler. Maint is high, even with modern materials. the Tornado isn't an exact replica of Peppercorns design. Modern materials and techniques have been used to construct it (stainless welded boiler for instance) but it will still need a total rebuild in around ten years and before then will prob need firetubes and firebox stays replacing. Experimental water tube boilers were built by rthe LNER toGresley designs, the LMS to Stanier designs and also the Southern under Buleid. The LMS even experimented with steam turbines. ALl ended up being rebuilt as conventional locomotives as they were far more costly to maintain.

To be honest Tornado is a waste of money, OK there were no Peppercorn Pacifics preserved but I can think of a whole bunch of other locomotive designs I would have recreated before the Peppercorn. There are plenty of LNER Pacifics in preservation from other classes. In fact there are 4 streamlined Gresley A4s on display in the National Railway Mueum at the moment to mark the anniversary of the Mallards record run. 'Our' A4 from the NYMR the 'Sir Nigel Gresly is one of them.

mugaliens
2008-Aug-01, 09:29 PM
With todays advances in metalurgy, and even complex hybrid ceramic impeller construction, designs which are far smaller, lighter, and more reliable than the old steam pistons can be built, while maintaining both normal and peak power capabilities.

Furthermore, using staged pressure-reduction radiators which channel much of the waste heat to pre-heating the incoming water (kept under pressure to keep it liquid before it flash-steams in the expansion chamber) not only is a great deal of previously wasted energy conserved, but a lot of previously wasted water is recycled.

Finally, just as modern trains use diesel-electric (diesel engine turning generators to power the electric motors for locomotion), modern steam trains would use a steam turbines to drive generators which do the same thing while weighing considerably less than diesels.

This is precisely why modern ships use steam turbines to power (directly) the propellers.

And this, from Wikipedia: "Another use of steam turbines is in ships; their small size, low maintenance, light weight, and low vibration are compelling advantages.[/quote]

I caveat this with the subsequent Wiki point:
(Steam turbine locomotives were also tested, but with limited success.) A steam turbine is only efficient when operating in the thousands of RPM range while application of the power in propulsion applications may be only in the hundreds of RPM and so requiring that expensive and precise reduction gears must be used."

Ah. The old reduction gearbox. Necessary for direct coupling. NOT necessary if the turbine drives a generator as in modern diesel-electric locomotives...

Finally,
This purchase cost is offset by much lower fuel and maintenance requirements and the small size of a turbine when compared to a reciprocating engine having an equivalent power."

I would imagine much of the boiler maintence previously mentioned had far more to do with the old-fashioned boiler+piston system than the steam itself. I contend that lightweight, high-rpm steam turbines (you could even gimbal mount them) driving an electric propulsion system would work rather well in today's locomotives.

As for water... Who's seen a train station without ample supplies of nearby hydrants? Just have the water company tap a line to be run at the mean usage rate, feeding a holding tank until it's ready to be downloaded.

Still, with a radiator system, that would be largely unecessary. While it won't work for cars made by Hughes (even small crashes can rupture a radiator), it will certainly work for trains.

captain swoop
2008-Aug-02, 11:14 AM
The boiler is still the weak point. Ships boilers are big and can be made a lot mor esolid. Locomotive boilers have a size and weight restriction. Water tube boilers are also complicated and fragile things even in ships. to miniaturize one for use ona locomotive compounds the problems. Plus even if it's built with modern materials the thing will need rebuilding every ten years or so.

If you are going to use it to power a generator why not put the boilers and turbines in a power station and just have electric motors on the train?

Not many ships have steam turbines these days, only the very big ones or quite old ones. Cargo ships are invariably diesel. and warships Gas Turbine, They get instant power and the machinery takes up a lot less space, is quieter and a heck of a lot cleaner and mor ereliable.

captain swoop
2008-Aug-02, 12:59 PM
OVS Bulleid the CME of the Southern railway from WW2 until Nationalisation tried a lot of innovative ideas to improve and modernise steam locomotives. His most interesting design was probably the Leader (http://www.bulleidlocos.org.uk/_ldr/ldrClass.aspx) class.

Jens
2008-Aug-02, 01:14 PM
Given the rising cost of oil, would this make economic sense to return to the age of steam?

I'm not sure if I really understand this. Steam isn't a form of energy in itself, but just a way to transform energy into electricity. You still need something, i.e. oil, to boil the water. In the real steam age, the most common fuel was coal. But my understanding is that it is getting difficult to find coal deposits at the surface of the earth. Hence you have to dig deeper, and hence the price of coal rises. I'm under the impression that we can't return to the "age of steam" in the way you mean it because we no longer have cheap coal deposits.

Neverfly
2008-Aug-02, 01:19 PM
Let's go nuclear.

captain swoop
2008-Aug-02, 01:32 PM
Don't forget the filth. Coal fired steam engines are filthy. We have 4 or 5 in steam on most days in the summer at Grosmont Shed on the NYMR, they produce tons of ash and cinders that need to be shoveled out of the smokeboxes and they cover everything with soot.

Neverfly
2008-Aug-02, 01:40 PM
Don't forget the filth. Coal fired steam engines are filthy. We have 4 or 5 in steam on most days in the summer at Grosmont Shed on the NYMR, they produce tons of ash and cinders that need to be shoveled out of the smokeboxes and they cover everything with soot.

This is one of those "bad movies" things.
How they show folks in fancy clothes on a train, and they open the window. And even stick their heads out windows.

Would never happen, because of the inevitability:

You'll get a cinder in your eye.

And if you manage to avoid inevitability; You will get one right in the middle of your forehead which you won't notice and have people staring when you get off the train.

danscope
2008-Aug-02, 02:52 PM
Still, If the choice is " Nothing's moving and we don't have oil"
or

"We have steam....let's go " , I'll take steam.

" Ask the rats. They have ways."
" From ' the Secret of Nimh ' " .

captain swoop
2008-Aug-02, 02:55 PM
One of our engines (http://adriandennis136.photos.me.uk/p39958726.html) coming off shed after a smokebox clean. note the huge pile of ash.


and Repton coming uphill out of Grosmont tunnel (http://adriandennis136.photos.me.uk/p43313078.html) Note the masses of smoke.

Imagine a busy city railway terminal or industrial area with dozens of these things all belching away.

I love them but I am glad they aren't in widespread use any more.

captain swoop
2008-Aug-02, 02:56 PM
Still, If the choice is " Nothing's moving and we don't have oil"
or

"We have steam....let's go " , I'll take steam.

" Ask the rats. They have ways."
" From ' the Secret of Nimh ' " .

Well then use the steam to power the turbines in a Power Station and run the trains on electricity.

Jeff Root
2008-Aug-02, 03:31 PM
Is the new engine powered by coal? The article doesn't say so and there is
no smoke coming from it in the photo -- just steam. (I couldn't look at the
video so don't know what it shows.)

-- Jeff, in Minneapolis

captain swoop
2008-Aug-02, 04:05 PM
It's a replica of a London North Eastern Railway A1 Pacific, designed by their last CME Arthur Peppercorn. It was a development of the Grfesley Pacifics of the 1930s. Although designed by the LNER they were actualy built after Nationalisation by British Rail. It's coal powered. The syndicate who built the replica have taken advantage of modern machining and construction methods and some modern materials. Some of this was for coat and some to increase longevity. For instance the Boiler is welded Stainless Steel.

JohnD
2008-Aug-02, 04:19 PM
What a pity, but no surprise, that the A1 Pacific enthusiasts built - an A1 Pacific.
To spend £3million on a new antique, when a far better demonstration of the strength of steam would have been one built to a modern design; perhaps the steam-electric idea as described by mugaliens above.

BUT, steam engines are the dog's whatsits for deep, low down torque, in fact max torque from a standstill.
That fantastic whooooooooooooooomph, whoooooomph, whooomph, whoomph, whoomph etc of an engine setting off.

John

captain swoop
2008-Aug-02, 05:09 PM
It would have cost a lot more than a few million to design and build an experimental 'modern' design. I can't believe that anyone would take the idea of a 'steam-electric' locomotive seriously.

It would be better to further develop some of the Rotary Cam valve gears like the Lentz (http://www.lner.info/article/tech/valvegear/lentz.shtml) and maybe the Crosti boiler (http://www.dself.dsl.pipex.com/MUSEUM/LOCOLOCO/francocrosti/francocrosti.htm) and maybe feed water heating or compund cylinders.

Neverfly
2008-Aug-02, 05:12 PM
BUT, steam engines are the dog's whatsits for deep, low down torque, in fact max torque from a standstill.
That fantastic whooooooooooooooomph, whoooooomph, whooomph, whoomph, whoomph etc of an engine setting off.

John

Which is part of it.
One large steam Loco can equal five diesels easy.

mugaliens
2008-Aug-02, 05:37 PM
The boiler is still the weak point.

Then don't use a boiler. Pump the water under pressure (high pressure, but a very small cross-sectional area) into the "boiler" which is just an array of high-pressure water lines such that the water is superheated - hot enough that when it's released, 100% of it turns to steam, which then drives the turbines.


Water tube boilers are also complicated and fragile things even in ships. to miniaturize one for use ona locomotive compounds the problems. Plus even if it's built with modern materials the thing will need rebuilding every ten years or so.

Then build it cheaply, and use a support structure that's solid, but one that's only loosely mated with the locomotive's chassis (like the rubber engine mounts used in cars).


If you are going to use it to power a generator why not put the boilers and turbines in a power station and just have electric motors on the train?

First, the train already has electric motors. Second, rail power is only feasible in subways (safety factor). Third, overhead rail power is both expensive and unsightly, and very impractical for long-haul trips, like London to Edinburgh. Fourth, it's also ill-suited for rails less travelled. That is, it's most efficient for short-distance, high-repetition routes.


Not many ships have steam turbines these days, only the very big ones or quite old ones. Cargo ships are invariably diesel. and warships Gas Turbine, They get instant power and the machinery takes up a lot less space, is quieter and a heck of a lot cleaner and mor ereliable.

True...

Of course, that's long been the case, as is why airliners use high bypass turbofans (greatest thrust/weight ratio, but at a substantial increase in cost) and why VLCCs use diesels (least $/cargoton-nm).

There's another reason warships like the USS Kitty Hawk use turbines instead of diesels. Steam turbines can be designed so that at all ahead standard, the ship's design cruise speed, the system is most efficient with respect to it's shaft hp/fuel ratio, while still being capable of sustained output at all ahead full, and short-term duration at all ahead flank.

Diesels, on the other hand, are generally designed to an efficient standard cruising speed (all ahead standard) with a small margin to proceed to all ahead full. Going full, however, significantly increases fuel consumption and engine wear.

captain swoop
2008-Aug-02, 08:59 PM
First, the train already has electric motors. Second, rail power is only feasible in subways (safety factor). Third, overhead rail power is both expensive and unsightly, and very impractical for long-haul trips, like London to Edinburgh. Fourth, it's also ill-suited for rails less travelled. That is, it's most efficient for short-distance, high-repetition routes.

Well, all the Southern region of British Rail is third rail electric including most of the commuter lines into London. 4200km of it

Overhead electric is used on the high speed intercity lines. Both the East Coast Main Line, London to Edinburgh and the West Coast Main London to Glasgow are overhead electric, and the new high speed route for the Eurostar through the Channel Tunnel is overhead electric 7578 km of it. Why would you think it impractical?

GeorgeLeRoyTirebiter
2008-Aug-02, 11:04 PM
Third, overhead rail power is both expensive and unsightly, and very impractical for long-haul trips, like London to Edinburgh.

London to Edinburgh (631km by rail) is considered to be long-haul over there? Wow. That's roughly comparable to Amtrak's electrified D.C.-Boston Northeast Corridor (735km). Impractical to electrify would be something like BNSF's L.A.-Chicago Transcon, at roughly 3540km.


...and the new high speed route for the Eurostar through the Channel Tunnel is overhead electric 7578 km of it.

Did you misplace a decimal point? That seems a bit high for the London-Paris and London-Brussels Eurostar routes. Is that the total for all Railteam high speed trackage?

Ronald Brak
2008-Aug-03, 12:35 AM
Here is a page that mentions a modern steam locomotive:

http://www.trainweb.org/tusp/slm.html

Modern manufacturing has allowed a huge increase in efficieny over traditional steam engines, however it is intereting to note that they still need to significant maintainace every month, unlike diesels. After their monthy boiler wash they use electricity to heat the boiler water to save on fuel costs. The efficieny of these modern steam engines is about 10% which is about one third that of a diesel locomotive.

mugaliens
2008-Aug-03, 11:58 PM
Well, all the Southern region of British Rail is third rail electric including most of the commuter lines into London. 4200km of it

Overhead electric is used on the high speed intercity lines. Both the East Coast Main Line, London to Edinburgh and the West Coast Main London to Glasgow are overhead electric, and the new high speed route for the Eurostar through the Channel Tunnel is overhead electric 7578 km of it. Why would you think it impractical?

Re-read my post:


it's also ill-suited for rails less travelled. That is, it's most efficient for short-distance, high-repetition routes.

4200 km, 7578 km...

That's total spaghetti length, with a lot of overlap. By your rules I could cite the US Rail system as being something like 1,000,000 km in length.

I'm talking single-line length, not the entire mesh of spaghetti.

captain swoop
2008-Aug-04, 12:11 AM
Did you misplace a decimal point? That seems a bit high for the London-Paris and London-Brussels Eurostar routes. Is that the total for all Railteam high speed trackage?

That's the total 25Kv overhead in the UK.

captain swoop
2008-Aug-04, 12:20 AM
As someone who works with steam locomotives (as a volunteer) on the NYMR where we have all kinds of vintages from 19th Century up to the last designs built in the 1950s I can say they are very labour intensive compared to the Diesels we run (we have a number of preserved units from the 1950s and 60s)

Diesels from the early 60s are still in regular mainline use on freight in the UK, they have probably had only 10% of the servicing and rebuilding needed by the steam locomotives of the same era. British Rail standard steam designs were as modern as any of the diesel locomotives built at the time and had the benefit of over a hundred years of development and refinement, they were the pinnacle of steam.
Swapping their cylinders for turbines and electric motors wouldn't make them more efficient or reduce the servicing, it would just add to the complexity and create more work. It's the boilers that are the critical component, they need the servicing and repair, the tubes replacing and fireboxes rebuilding every few years.

Ronald Brak
2008-Aug-04, 12:55 AM
Steam won't save energy over electric or diesel. Modern steam locomotives are about 10% efficient. Diesels about 30%. Wood or coal can be burned in a steam locomotive for perhaps 10% efficiency or you can burn it in a power station for perhaps 35% efficiency, transmit it at 93% efficiency and run an electric train off it at 90% efficiency for an all up efficiency of nearly 30%, almost three times better than a steam engine.

Noclevername
2008-Aug-05, 01:53 AM
Don't forget the filth. Coal fired steam engines are filthy. We have 4 or 5 in steam on most days in the summer at Grosmont Shed on the NYMR, they produce tons of ash and cinders that need to be shoveled out of the smokeboxes and they cover everything with soot.

Why coal? Steam can use anything that produces heat.

JustAFriend
2008-Aug-05, 02:00 AM
My Dad was really into steam and we attended a number of Midwestern steam shows when I was a kid. We loved to watch the parades of antique steam tractors.

However, 50 people got hurt back in 2001 when one exploded:

All Things Considered, July 30, 2001 · From member station WCPN, Janet Babin reports the county fair in Medina, Ohio, opened today on schedule despite a fatal accident yesterday. An antique steam-powered tractor exploded killing four people and injuring nearly 50 people, including 4-H children bringing their animals to the fairground.

http://www.npr.org/templates/story/story.php?storyId=1126691

clint
2008-Aug-05, 02:27 AM
Well then use the steam to power the turbines in a Power Station and run the trains on electricity.

Steam is already being used in that way... (http://news.bbc.co.uk/2/hi/science/nature/6616651.stm)

http://newsimg.bbc.co.uk/media/images/42879000/gif/_42879551_solar_reflect_inf416.gif


1. The solar tower is 115m (377ft) tall and surrounded by 600 steel reflectors (heliostats). They track the sun and direct its rays to a heat exchanger (receiver) at the top of the tower
2. The receiver converts concentrated solar energy from the heliostats into steam
3. Steam is stored in tanks and used to drive turbines that will produce enough electricity for up to 6,000 homes

captain swoop
2008-Aug-05, 08:41 AM
Why coal? Steam can use anything that produces heat.

If you are going to use oil then just stick it into a diesel, why bother with steam?

captain swoop
2008-Aug-05, 08:48 AM
My Dad was really into steam and we attended a number of Midwestern steam shows when I was a kid. We loved to watch the parades of antique steam tractors.

However, 50 people got hurt back in 2001 when one exploded:


I was at the Pickering (http://pickeringtractionenginerally.theeventsoffice.co.uk/whats_on.htm) Rally this weekend (Over 100 steam tractors, ploughing engines, rollers etc)
It's been going since the 1960s and there hasn't been a single boiler explosion. Before you can steam a boiler you have to get a 'Boiler Ticket' which is valid for a fixed number of years (5 or 10 depending on type). Tests are strict. It's the rally at Ducombe Park soon, not as big as pickering but there will be 30 or 40 engines there.

Pickering is a huge event, there are something like 700 vintage cars and military vehicles, Steam ploughing and threshing displays, vintage 'steam' fair with fairground organs and old rides, a brilliant 'wall of death' 3 stages of live entertainment and a massive 'Beer Tent' selling Blask Sheep Brewery 'real ale'

NEOWatcher
2008-Aug-05, 12:24 PM
However, 50 people got hurt back in 2001 when one exploded:
I was about 7 or 8 miles away from that one, and we heard it and the subsequent bevy of sirens. My friend's daughter was at the fair at the time (thankfully with a cell phone).

Apparently; Pennsylvania authorities were called in for the investigation since they have an inspection process and Ohio doesn't.
Here's detail (http://www.steamtraction.com/archive/5410/).
Here's a report summary (http://www.doli.state.mn.us/boilerohio.html) in a letter to MN (with pictures)

mugaliens
2008-Aug-05, 09:16 PM
If you are going to use oil then just stick it into a diesel, why bother with steam?

That's the same arguement I use with the "hydrogen economy." If you're going to use hydrogen generated from electricity, then skip the 23% efficiency during the conversion and just stick to using the electricity."

captain swoop
2008-Aug-05, 09:36 PM
I was about 7 or 8 miles away from that one, and we heard it and the subsequent bevy of sirens. My friend's daughter was at the fair at the time (thankfully with a cell phone).

Apparently; Pennsylvania authorities were called in for the investigation since they have an inspection process and Ohio doesn't.
Here's detail (http://www.steamtraction.com/archive/5410/).
Here's a report summary (http://www.doli.state.mn.us/boilerohio.html) in a letter to MN (with pictures)

Reading that report I can say that the thing would have failed even a visual inspection in the UK and would never have been allowed in a public show or on to the road. Ity ould certainly have failed its hydraulic test of 60lb over max certified pressure.

cjl
2008-Aug-06, 07:34 PM
That's the same arguement I use with the "hydrogen economy." If you're going to use hydrogen generated from electricity, then skip the 23% efficiency during the conversion and just stick to using the electricity."
The difference is that hydrogen is easier to store than pure electricity given current technology. Batteries are improving, yes, and there are alternatives (supercapacitors, etc) that seem promising, but right now, electricity can't quite match fuel (hydrogen or otherwise) for overall convenience.

captain swoop
2008-Aug-06, 09:29 PM
This building replicas of Locomotives that have no preserved examples is catching. There are plans to build a replica of an LMS Patriot (http://www.lms-patriot.org.uk/project.html)
Apart from one not being preserved I can't think why, they were just developments of the old LNWR 'Cloughtons', in fact the first of the class was a direct rebuild of a Cloughton.

It's their money I suppose and they are well enough regarded by the enthusiasts.

captain swoop
2008-Aug-06, 09:44 PM
Further investigation revgeals projects to build a whole load of new locomotives. A Great Western Grange (http://www.6880.co.uk/) a Southern H2 Atlantic (http://www.bluebell-railway.co.uk/bluebell/locos/atlantic/). Now they are pretty engines I can see the attraction. Didcot (http://www.didcotrailwaycentre.org.uk/news/latest.html#news02) are planning a Great Western 'County' but they are using an old LMS '8F' boiler as the basis so it's a bit of a hybrid.
The Weardale Railway (http://www.wrlpg.com/page13.htm) are going to produce a G5 tank loco. Now I am all for this, the G5 was the epitome of branch line passenger operations, and as it's an old North Eastern Railway Loco and one was in the Shed at Guisborough up until the 9050s I support this.

The 82045 society (http://www.82045.org.uk/) are planning to build a number of 'Riddles' BR Standard 3MTs.

And the 72010 society (http://72010-hengist.org/) are going to build a BR Standard Pacific.

A common thread seems to be providing new motive power for the 'Heritage' lines. The youngest of the 'real' locomotives is over 50 years old now. At present there are several thousand preserved locomotives and many hundreds of miles of preserved 'heritage' lines. At the NYMR we have a 30 mile run from Whitby to Pickering and arounf a dozen working mainline locomotives. It's big business, last year there were more than half a million paying passengers on our line.

Sticks
2008-Aug-28, 11:37 AM
This seems an interesting variant (http://www.guardian.co.uk/environment/2008/aug/27/alternativeenergy.energy)

:think:


Steam power may have an old-fashioned image, but British engineers think it can improve the efficiency of the internal combustion engine

Say "steam power" and you conjure up images of Stevenson's rocket, Isambard Kingdom Brunel and the heyday of the Victorian railways – romantic, but hardly the stuff of a clean, cutting-edge technology.

But steam could be about to make a comeback thanks to a company that is trying to make the internal combustion engine more efficient.

Clean Power Technologies, in Newhaven on the English south coast, is developing steam hybrid engines that claw back some of the immense amount of energy wasted by the internal combustion engine. Ultimately they aim to develop a car engine that runs partly on steam power

NEOWatcher
2008-Aug-28, 12:10 PM
This seems an interesting variant (http://www.guardian.co.uk/environment/2008/aug/27/alternativeenergy.energy)

:think:
I don't know if the "variant" is interesting since I've been hearing about reclaiming waste heat for as long as I can remember.

What I do find interesting is the fact that someone is actually trying to come out with an actual product. With weight and cost issues that this will add (until they get it perfected) I think they are choosing the right market to start with.

ravens_cry
2008-Aug-28, 12:24 PM
A subject I have a certain fondness for is steam PLANES, as in aeroplanes.
http://www.dself.dsl.pipex.com/MUSEUM/TRANSPORT/steamplane/steamplane.htm
A book I own called The Conquest of the Air by Frank Howard and Bill Gunston has much to say about the suprisingly doable possibilities that arose in the early chapters.

danscope
2008-Aug-28, 06:14 PM
This seems an interesting variant (http://www.guardian.co.uk/environment/2008/aug/27/alternativeenergy.energy)

:think:

Hi Sticks, I think that this is where the closed circuit steam/ electric hybrid
becomes quite usefull. You have the advantage of electric propulsion
instantly, while the steam plant comes online. The steam plant runs at proper efficiency, charging the battery. This opens doors to practical and convenient
steam technology consistent with automotive demands, both short and long trip.
And it speaks to multiple fuels as well.

Best regards, Dan

Stuart van Onselen
2008-Aug-29, 02:12 PM
If (and it's a big If) you have access to the correct blend of technology, you might be able to run a car on a gas/steam two-phase turbine assembly, such as found in some more modern power stations. This would potentially have a ludicrously high efficiency, maybe as high as 70% to 80%.

It works like this: Start by burning any flammable gas in a gas turbine. With suitably high temperatures, gas turbines are already much more efficient than current internal combustion engines. But the exhaust is frighteningly hot. Not only is this inconvenient at best and downright dangerous at worst, it's also a huge waste of energy!

So we take that hot exhaust, and use it to generate steam that powers a steam turbine. And since the steam is being generated by the "leftover" energy from the gas turbine's exhaust, your efficiency goes way up.

Of course, what works well in a massive power-station does not necessarily scale well to the size of a locomotive, or still further to that of a car.

Turbine engines have been tried on cars before, with little success. Turbines don't like changes in speed. Spool-up and spool-down times are long. And they're actually inefficient on a small scale. I don't know why, exactly, but they just are. The M1 Abrams is a gas-guzzler of note, even compared to the other modern MBTs, which all use diesel engines.

Now the spool-up / spool-down problem can be cured by using a hybrid-electric scheme. Keep the gas turbine running at its ideal, most-efficient speed, and use a battery or ultra-capacitor to buffer the output. Instead of having to slow the turbine, just keep charging the battery. Instead of speeding it up, use the extra charge you saved earlier to drive the electric motors harder.

Of course, this adds some complications. Turbine engines are renowned for their high power-to-weight ratio. The M1, for example, uses a "power pack" that is much smaller and lighter than the equivalent diesel-engine would be. But in a hybrid, all of that gain (and maybe a lot more) would be taken up by the volume and mass of the generator, battery and electric motor.

And this is before we add the steam turbine. Even more efficiency, but even more weight. You can run a steam-turbine without a huge boiler, like on an old steam locomotive. But you do still need some water, plus piping, plus a radiator to cool the water again. Plus the weight of the turbine itself, of course.

So while I like to fantasise about some compact, high-power, high-efficiency twin-turbine car engine, the idea is probably a bust from the word "go". A power-station can be built big to increase efficiency without then losing all that gain because it has to drag that extra that weight around.

But a thought occurred to me as I was writing this: What about ships, or even locomotives? At that scale, the gas/steam/electric power-train might prove useful, and reduce fuel costs by at least half, maybe more!

By the way, does anyone know why merchant shipping uses diesel engines almost exclusively? I was under the impression that turbines at that scale would be more efficient, reducing fuel costs to a degree that quickly pays back the huge costs of a turbine. And turbines need less maintenance than diesels, which is another cost saving.

I know military vessels use turbines, but I guess they're most interested in speed. Fuel-efficiency matters little when you're being shot at! (Or, embarrassingly, when you take so long to transit that you miss the whole war. :))

danscope
2008-Aug-30, 12:59 AM
Hi,
By comparison, large diesel engines are easier to operate than steam ,
and do not require an steam engineering license.
Automating the process for a small ceramic steam turbine in a closed loop
configuration , ...to charge a battery may have the potential to solve many problems and deliver more power on demand when required, without instant demand on the steam plant. The turbine can begin producing power when it comes on line, and be shut down in advance of the destination.
This has nothing to do with "gas Turbines" which are inherently difficult, expensive, and suffer from both foreign particle ingestion as well as the high exhaust gas tempeatures you mentioned previously. By going steam/electric, you void the requirement of instant power directly from the turbine. This is the beauty of an hybrid design.
It can be an extraordinary advantage.

Best regards, Dan

zerocold
2008-Aug-30, 05:13 AM
Is there any project around locomotive coke gas propulsion?, that would be interesting

Neverfly
2008-Aug-30, 05:18 AM
Is there any project around locomotive coke gas propulsion?, that would be interesting
No because the Coke™ would dissolve the locomotives;) :whistle:

The Backroad Astronomer
2008-Aug-30, 05:38 AM
Is there any project around locomotive coke gas propulsion?, that would be interesting
Also it make drinking it very costly.

Tuckerfan
2008-Aug-30, 11:04 AM
Steam won't save energy over electric or diesel. Modern steam locomotives are about 10% efficient. Diesels about 30%. Wood or coal can be burned in a steam locomotive for perhaps 10% efficiency or you can burn it in a power station for perhaps 35% efficiency, transmit it at 93% efficiency and run an electric train off it at 90% efficiency for an all up efficiency of nearly 30%, almost three times better than a steam engine.

Wrong. Modern steam engines can be made to operate around 40% or better efficiency, diesels, and other internal combustion engines top out below 30%. The reason for this is rather simple: Much of the energy in fuels like diesel and gasoline when they're used in internal combustion engines is lost to noise and heat. If you want to get real fancy in the numbers, you can start factoring things like transmission losses, where internal combustion engines lose out again, because they have so many more moving parts.

When steam engines fell out of wide use in the 1950s, the operating cost of them was on par with that of diesels. It should be noted that a lot more R&D money was being poured into diesels and other internal combustion engines at that time, and in the years since, almost nothing has gone into steam engine design.

This site has a PDF of a research paper on the difference between a modern steam locomotive (i.e. designed from scratch with completely modern materials) versus that of diesel. (http://www.trainweb.org/tusp/news/news.html#coal) I sent the link to an engineer I know in the powerplant industry and this was her comments on it:

I've had a brief look at the paper/PDF you linked to, and overall I think the author makes some good analyses, but they may be missing a few things. The first one is emissions - I'm uncertain that a new coal-powered train could pass EPA emissions regs in terms of PM10, PM2.5, SO2, and NOx without significant amounts of pollution control equipment on the train.

I also think some of his costs are iffy, esp. the coal costs, the retrofit for things like coaling stations and water supply, and the modifications to the trains. However, that's something I'm less sure of.

Overall, however, I think it's at least feasible and I think if the economics really worked, and the emissions regs could be met, it could be an interesting positive alternative. At least, unless you want to throw in biodiesel-fueled locomotives into the mix...

Don't get me wrong, however - the study this person has done is much better than most. It's at the level of what we'd call a "second level feasibility study" in Engineering, and assuming that his numbers are right, there's a lot of value in it. (a third-level analysis would have a regulatory/legal review, economic sensitivity factors, and possibly a political study as well. A 4th-level would be a pilot study of real operation of a train, and a 5th level would be operation of a small fleet.). My main concern, again, is that I'm no train expert, but I think the EPA would work hard to require emissions regs from coal trains that could make it very difficult to realize them. And I quibbled with econ, well, you can always do that...I intend to show the paper at work to our railroad expert and see what he thinks, and read it more closely myself.

It should also be noted that there are boiler designs (such as the Doble and Lamont) that have practically no chance of exploding, and have not been used in a steam loco, AFAIK. Aerogels are also apparently dropping in price rather dramatically, so it might be possible to use those as insulation, which would reduce fuel costs considerably. Water shouldn't be that big of an issue if you installed a condensor on the loco.

One advantage that a properly designed steam loco would have over a diesel is that since a steamer's fuel "agnostic" it could use whatever was cheaper at the moment.


A subject I have a certain fondness for is steam PLANES, as in aeroplanes.
http://www.dself.dsl.pipex.com/MUSEU...steamplane.htm
A book I own called The Conquest of the Air by Frank Howard and Bill Gunston has much to say about the suprisingly doable possibilities that arose in the early chapters.Youtube clip of the only passenger carrying steam plane ever built. (www.youtube.com/watch?v=UPEv_M7p4fA) (it shows up at about the 1:50 mark) Technical info about the plane and its engine. (http://www.rexresearch.com/besler/beslerst.htm)

Article about company planning to sell steam-powered lawnmowers in the near future. (http://www.popsci.com/scitech/article/2008-05/steam-under-hood)

Anyone interested in state-of-the-art steam locos when they ceased being built should check out La Locomotive a Vapeur by Andre Chapelon (http://www.goodheartvideo.com/viewdetail.asp?item=BOOK%2DVAPEUR&catID=3) (Yes, it is in English.) as he did more to push the envelope in the waning years than anyone else.

captain swoop
2008-Aug-30, 04:18 PM
Chapelons locomotives may have been efficient but they were costly to run and maintain, the same with Bulleids advanced designs on the SOuthern Railway.

djellison
2008-Aug-30, 07:17 PM
London to Edinburgh (631km by rail) is considered to be long-haul over there? Wow.

Well - to go much further on the mainland UK - you need a hull, or wings.

Tuckerfan
2008-Aug-30, 08:46 PM
Chapelons locomotives may have been efficient but they were costly to run and maintain, the same with Bulleids advanced designs on the SOuthern Railway.

One has to wonder if that'd still be the case with modern electronics.

captain swoop
2008-Aug-30, 08:58 PM
On traditional locomotives all the various devices to increase efficiency were all outweighed by increased maint costs. When the BR Standard Classes were built in the 1950s some of the big class 8F freight locomotives had Crosti boilers that were more efficient but they were all rebuilt later, same with Compound locomotives earlier in the century and various locomotives built with various feed water heaters, valve gears boilers etc.
All of these devices made the loco more efficient but increased the costs and length of maintenance. While coal was cheap they weren't needed.

Ronald Brak
2008-Sep-02, 12:42 AM
Wrong.

Are there modern steam locomotives that get significanty more than 10% efficiency? Diesel electrics might top out at 30% efficiency, but diesel mechanicals have significantly higher efficiencies.

Tuckerfan
2008-Sep-02, 01:03 AM
Are there modern steam locomotives that get significanty more than 10% efficiency? Diesel electrics might top out at 30% efficiency, but diesel mechanicals have significantly higher efficiencies.Technically, there are no modern steam locos. You, however, have seemed to have latched onto this "10% efficiency" for no logical reason, and no supportive documentation whatsoever. I, OTOH, have posted several refences which put steam engines at higher than internal combustion engines. Let's see your documentation to back up your assertion.

Let's take this a step further, while we're at it. Jay Leno took his steam powered Doble for an emissions test. (http://www.popularmechanics.com/automotive/jay_leno_garage/1302916.html)
I took the Doble to the smog station to have its exhaust certified and its emissions are 13 parts per million, which means my 1925 Doble with its 80-year-old technology passes all current smog laws. Nothing like 2 million BTU to burn up all the fuel. There's nothing left over, literally. It's just pffft. Gone.Odds are, his Doble was running kerosene, which isn't all that different than diesel, and it certainly had no pollution controls on it at all. Can a diesel without pollution controls match that?

Ronald Brak
2008-Sep-02, 01:30 AM
Technically, there are no modern steam locos.

In the 1990s SLM built eight rack steam locomotives using modern construction techniques and technology. This resulted in improvments over the 1933 original design of:

Service weight reduced 25 percent
Power increased 36 percent
Power-to-weight ratio increased 82 percent
Fuel consumption per trip reduced 41 percent
Fuel consumption per passenger trip reduced 61 percent
Maximum speed increased 56 percent

I thought this counted as modern. Sorry for getting it wrong. I take it we are agreed that no steam locomotive in existance has significantly greater than 10% efficiency.


You, however, have seemed to have latched onto this "10% efficiency" for no logical reason, and no supportive documentation whatsoever. I, OTOH, have posted several refences which put steam engines at higher than internal combustion engines. Let's see your documentation to back up your assertion.

Check out my first post on this thread, you must have missed it. But don't worry, it's easy enough to miss a post.

Tuckerfan
2008-Sep-02, 01:49 AM
In the 1990s SLM built eight rack steam locomotives using modern construction techniques and technology. This resulted in improvments over the 1933 original design of:

Service weight reduced 25 percent
Power increased 36 percent
Power-to-weight ratio increased 82 percent
Fuel consumption per trip reduced 41 percent
Fuel consumption per passenger trip reduced 61 percent
Maximum speed increased 56 percent

I thought this counted as modern. Sorry for getting it wrong. I take it we are agreed that no steam locomotive in existance has significantly greater than 10% efficiency. Note that it says they have been "modernized." That is not the same as designing and building a loco from scratch. I can drop a modern engine in a '57 Chevy, but it still won't get the same kind of mileage as a completely modern vehicle. Realistically, they did the same thing with those locos.

Note, also that they're referring to "thermal efficiency," which is a completely different kettle of fish than operating efficiency. Given that the heat generated by a diesel engine is used solely for igniting the fuel, I doubt that they have much of a thermal efficiency, either.

Furthermore, they're keeping the cosmetic appearance of the original locomotives, which no doubt limits the amount of improvements that can be done.

And further down in your link, we find this interesting tidbit:

About 10 to 15 steam projects total were under consideration at SLM during the 1990's. Calculations for steam in Russia, for example, have shown that a natural gas fired steam locomotive would save an estimated 60 percent in fuel costs compared to diesels and 80 percent compared to electric locomotives. Air pollution would also be considerably reduced. Examination of the conditions in different countries show diverse reasons for considering new steam locomotives: low cost of fuel, local availability of fuel, low pollution, and simplicity of construction resulting in long service life and making long-term local maintenance practical.Also of interest, SLM built new marine steam engines for Lake Geneva steamers, actually converting them back to steam from diesel propulsion.(bolding mine)


Check out my first post on this thread, you must have missed it. But don't worry, it's easy enough to miss a post.
Again, that is referring to older designs which have been upgraded, not one that has been designed from scratch. There's a big difference. They're also a decade old constructions, and materials science has advanced tremendously in that short period of time. Aerogels (http://www.aerogel.com/), for example, have just recently come down in price where they're economically practical for a wide variety of operations. Given that there's nothing better known as an insulating material, I'd imagine that a boiler insulated with those would be much more efficient.

Ronald Brak
2008-Sep-02, 01:55 AM
Are we disagreeing on anything, Tuckerfan?

Tuckerfan
2008-Sep-02, 02:10 AM
Are we disagreeing on anything, Tuckerfan?Yes. You're claiming that "thermal efficiency" is somehow equivalent to "operational efficiency." They're not. You're also claiming that reworked older designs are relevant in to the discussion, again, they're not.

You're also stating that there's no way an steam loco could be as efficient to operate as a diesel, when your own links state otherwise.

You've also failed to answer my questions regarding the pollution emisssions of steamers when compared to those of a diesel. (Of course, the portion of your link that you decided to ignore, states quite clearly that steamer emissions are much lower.)

Additionally, I've provided a link to a doctorial thesis about steam vs diesel locos which states that steam is superior, and while I don't expect you to have the same opinions of the engineer that I showed the paper to (since I know her and you don't), you haven't offered up anything that contradicts her statements. Mind you, I don't need anything like a "hard" cite for this, but something with some weight behind it, that I can toss back at her and see what she thinks of it.

Ronald Brak
2008-Sep-02, 02:28 AM
Yes. You're claiming that "thermal efficiency" is somehow equivalent to "operational efficiency."

I didn't.


You're also claiming that reworked older designs are relevant in to the discussion, again, they're not.

What are we discussing?


You're also stating that there's no way an steam loco could be as efficient to operate as a diesel

I didn't say that.


You've also failed to answer my questions regarding the pollution emisssions of steamers when compared to those of a diesel. (Of course, the portion of your link that you decided to ignore, states quite clearly that steamer emissions are much lower.)

I never mentioned pollution.


Additionally, I've provided a link to a doctorial thesis about steam vs diesel locos which states that steam is superior, and while I don't expect you to have the same opinions of the engineer that I showed the paper to (since I know her and you don't), you haven't offered up anything that contradicts her statements. Mind you, I don't need anything like a "hard" cite for this, but something with some weight behind it, that I can toss back at her and see what she thinks of it.

Have I disagreed with any of it?

I said modern steam locomotives are about 10% efficient. I have explained what I meant by modern steam locomotive and have apologized for using the word modern. So now that you know what I meant by the words modern steam locomotives, is there anything we disagree on?

Tuckerfan
2008-Sep-02, 03:22 AM
I didn't.
Yes, you did. Your site mentions "10% thermal efficiency" which had no bearing when it comes to comparing diesels to steam. Period. Paragraph. So why bring it up? Because you want to obscure the issue.



What are we discussing? Cut the crap. That's about the cheapest, sleeziest, debating tactic around. I've not stooped to such levels, nor will I. If you can't handle being wrong, then bow out of the thread. Its a lot classier.




I didn't say that. Again with the sleezy tactics. Sure you didn't come directly out and say that, because you know you'd be wrong, but you're more than happy to dance around the subject, while implying that something which is totally irrelevant to the discussion is germaine to it.




I never mentioned pollution. And where did I say you did? Oh, that's right, I didn't, but rather than admit you don't know what you're talking about, or even answering me when I asked you about pollution, you, again, fall back on cheap tricks.




Have I disagreed with any of it? Again, you lack the courage to do so, because you know you're wrong, but you're more than happy to give the implication that you do disagree with it, because you'd rather engage in semantic games than examine the issue.


I said modern steam locomotives are about 10% efficient. Carefully "forgetting" the thermal part, which as I have pointed out time and time again, is utterly meaningless in this discussion. Additionally, your cite makes no mention on that page as to what "thermal effficency" means, and why it might, or might not be important. It does not state that this is derived from how much energy is used to heat the boiler, or if its derived from how much heat is lost by the boiler, or if its the transfer of heat, via steam jacket to the cylinders (which would thus keep them at a more optimal operating temperature), or any of a dozen other possibilities. In short, it is a meaningless number.
I have explained what I meant by modern steam locomotive and have apologized for using the word modern. So now that you know what I meant by the words modern steam locomotives, is there anything we disagree on?Of course, otherwise you wouldn't be continuing this discussion. I've pointed to cites, which quite clearly state that steam engines operate at above 40% efficency, which is better than diesels that operate at below 30% efficency. Your continued insistence upon using "thermal efficiency" without bothering to offer up a cite showing what the thermal efficiency of diesels is, and why it is in any way relevant goes beyond disingenuous and is clearly designed to do nothing more than obscure the issue.

Ronald Brak
2008-Sep-02, 03:28 AM
Tuckerfan, I wrote:


Steam won't save energy over electric or diesel. Modern steam locomotives are about 10% efficient. Diesels about 30%. Wood or coal can be burned in a steam locomotive for perhaps 10% efficiency or you can burn it in a power station for perhaps 35% efficiency, transmit it at 93% efficiency and run an electric train off it at 90% efficiency for an all up efficiency of nearly 30%, almost three times better than a steam engine.

I have appologized for useing the words modern steam locomotives. If I rewrite it to correct this mistake and make it clearer it becomes:


Using any steam locomotives that currently exist today won't save energy over electric or diesel because they are only about 10% efficient. Diesels about 30%. Wood or coal can be burned in the most efficent steam locomotive that currently exists in today for perhaps 10% efficiency or you can burn it in a power station for perhaps 35% efficiency, transmit it at 93% efficiency and run an electric train off it at 90% efficiency for an all up efficiency of nearly 30%, almost three times better than any steam locomotive that currently exists today.

Is there anything there you disagree with?

Tuckerfan
2008-Sep-02, 03:39 AM
Tuckerfan, I wrote:



I have appologized for useing the words modern steam locomotives. If I rewrite it to correct this mistake and make it clearer it becomes:



Is there anything there you disagree with?

Yes, the whole "10% efficency" vs "30% efficency" which I've repeatedly pointed out and cited is wrong. You, OTOH, haven't cited anything relevant as to proof of your position on the matter. And since you probably missed it, let me just quote from this article (http://www.popsci.com/scitech/article/2008-05/steam-under-hood) that I linked to earlier about the efficency of steam engines vs internal combustion engines.

By zealously reusing every possible bit of heat, steam engines can convert up to 46 percent of incoming energy into torque. Most gas-powered internal combustion engines, in contrast, are only about 25 percent efficient. Schoell’s prototype also emits much cleaner exhaust than a standard gas engine; unburned fuel sits in the combustion chamber until the engine fires up again, and eventually nearly all the waste particles and unused fuel are incinerated.(bolding mine)

Show me where diesels can beat that.

Ronald Brak
2008-Sep-02, 03:44 AM
So do you believe there are steam locomotives in the world today that are more than about 10% efficient? If you do then we disagree on that, although I freely admit I could be wrong.

Tuckerfan
2008-Sep-02, 03:49 AM
So do you believe there are steam locomotives in the world today that are more than about 10% efficient? If you do then we disagree on that, although I freely admit I could be wrong.

What kind of efficency are we talking about here? Thermal efficency? If so, then I have to ask you, again, what's the relevance to the issue is.

I'm also going to ask you again your source on the information about diesels being "30% thermal efficent."

Answer those, and then I'll respond to your question. Otherwise, we're done here.

Ronald Brak
2008-Sep-02, 04:02 AM
What kind of efficency are we talking about here? Thermal efficency? If so, then I have to ask you, again, what's the relevance to the issue is.

The ratio of output to input. In this case the kinetic energy of the locomotive's movement to the thermal energy of its fuel.


I'm also going to ask you again your source on the information about diesels being "30% thermal efficent."

Well, here is a wikipedia article on diesel engines:

http://en.wikipedia.org/wiki/Diesel_locomotive

Tuckerfan
2008-Sep-02, 04:36 AM
The ratio of output to input. In this case the kinetic energy of the locomotive's movement to the thermal energy of its fuel. Except that it isn't heat that drives a diesel, its the force of the explosion, any heat that's produced is an unwanted side-effect for the most part.




Well, here is a wikipedia article on diesel engines:

http://en.wikipedia.org/wiki/Diesel_locomotive

Which, buried way down says:
Diesel’s theoretical studies demonstrated potential thermal efficiencies for a compression ignition engine of 73% (compared with 6-10% for steam), and a 1897 one-cylinder prototype operated at a remarkable 26% efficiency. Note a number of problems with that piece of information. First of all, it lists a diesel having a theoretical capacity far greater than anything we've achieved so far. Given all the money that's been poured into diesel engine research, were that to be an accurate estimate, we'd no doubt be seeing far higher than the 30% figure you've claimed. It also contradicts this Wiki article on steam engines which says: (http://en.wikipedia.org/wiki/Rankine_cycle)
A Rankine cycle describes a model of the operation of steam heat engines most commonly found in power generation plants.
The Rankine cycle is sometimes referred to as a practical Carnot cycle as, when an efficient turbine is used, the TS diagram will begin to resemble the Carnot cycle. The main difference is that a pump is used to pressurize liquid instead of gas. This requires about 100 times less energy than that compressing a gas in a compressor (as in the Carnot cycle).

This gives a theoretical Carnot efficiency of around 63% compared with an actual efficiency of 42% for a modern coal-fired power station. (bolding mine)

I'll note that powerplant steam engine designs are more advanced than anything which has been used in a locomotive to date. So, quite clearly, we have a contradiction here. Given that the page on steam engines matches everything, I've seen on steam engines, while the one on diesels does not match what I've read about them, I'm going to side with the one on steam engines. You're free to do whatever you choose.

As to your question about steam engine efficiencies, and if a steam loco has been built that operates higher than 10%, I can't say for certain, but given that the folks on the Steam Tech group (http://groups.yahoo.com/group/steam_tech?v=1&t=search&ch=web&pub=groups&sec=group&slk=1) do a lot of work with steam trains and put the efficiencies of some locos at quite high a number (at least when compared to the 10% thermal efficency number you're claiming), I'm going to say there probably are some out there.

danscope
2008-Sep-02, 04:57 AM
Hi,
You might find that the reason diesel is so powerfull is that it supplies a smoothly expanding flame front "Further" down the cylinder , in which the power pulse is elongated, and NOT an explosion. Detonation is a very bad thing to
experience in reciprocating engines. After we have done as much as we can with gasoline engines and 100 octane fuel, we turn to diesel for smooth, improved torque to accomodate our high power applications , especially power generation,
earth moving machines via hydraulics or geared reduction . This comes at a price as per weight and expensive design and materials.
Diesels are a little less thirsty as well. But their fuel does not tolerate alcohol
dilution. Bio diesel is another matter.

Best regards, Dan

Tuckerfan
2008-Sep-02, 05:15 AM
Hi,
You might find that the reason diesel is so powerfull is that it supplies a smoothly expanding flame front "Further" down the cylinder , in which the power pulse is elongated, and NOT an explosion. Detonation is a very bad thing to
experience in reciprocating engines. After we have done as much as we can with gasoline engines and 100 octane fuel, we turn to diesel for smooth, improved torque to accomodate our high power applications , especially power generation,
earth moving machines via hydraulics or geared reduction . This comes at a price as per weight and expensive design and materials.
Diesels are a little less thirsty as well. But their fuel does not tolerate alcohol
dilution. Bio diesel is another matter.

Best regards, Dan
Actually, detonation is exactly how internal combustion engines operate. Its only bad when it happens at the wrong time. Nor have we done everything we can with gasoline engines, there are steady improvements being made to them all the time. Diesel engines tend to be higher torque than gassers, at least part of that is due to diesel fuel having a much higher BTU content than gasoline (kerosene is even higher still and some people run their diesel engines on it).

Biodiesel in chemically fairly close to petroleum based diesel. The main differences being that biodiesel is slightly lower in BTUs, and is a bit more reactive to certain rubber based compounds (which is why certain years of VW [i]can't be run on biodiesel without completely replacing the fuel lines).

Ronald Brak
2008-Sep-02, 05:28 AM
Except that it isn't heat that drives a diesel, its the force of the explosion, any heat that's produced is an unwanted side-effect for the most part.

So it's not the heat of the burning fuel that powers a diesel, it is the rapid movement of molecules that results when the fuel is burned. Okay, got it. I learn something new everyday on BAUT.

The wikipedia article states:


Large diesel trucks, buses, and newer diesel cars can achieve efficiencies around 45%

Are you saying this is wrong? And if it's wrong, and if it is wrong, do you think it is too high or too low?


As to your question about steam engine efficiencies, and if a steam loco has been built that operates higher than 10%, I can't say for certain, but given that the folks on the Steam Tech group do a lot of work with steam trains and put the efficiencies of some locos at quite high a number (at least when compared to the 10% thermal efficency number you're claiming), I'm going to say there probably are some out there.

So you are not certain that there are locomotives with efficiencies higher than about 10%, but you think there probably are some.

So our disagreement so far is this: You think there probably are steam locomotives with efficiencies greater than about 10%. I doubt that there are.

Tuckerfan
2008-Sep-02, 06:29 AM
So it's not the heat of the burning fuel that powers a diesel, it is the rapid movement of molecules that results when the fuel is burned. Okay, got it. I learn something new everyday on BAUT.

The wikipedia article states:



Are you saying this is wrong? And if it's wrong, and if it is wrong, do you think it is too high or too low? Where? In the article you linked to, all it says about trucks are:
In later years, mechanical transmissions have been used again. These modern mechanical transmissions are originally made for trucks and based on the fact that multiple truck engines are a common solution for diesel railcars after year 2000, due to high development costs for engines because of environmental requirements.

and:

Progress was slow, however, due to the poor power-to-weight ratio of the early engines, as well as the difficulty inherent in mechanically applying power to multiple driving wheels on swivelling trucks (bogies).There's nothing there about diesel engines in trucks. In the Wiki article on diesel engines (http://en.wikipedia.org/wiki/Diesel_engine) it says something similar to what you've posted:
Even though diesel engines have a theoretical fuel efficiency of 75%, in practice it is less. Large diesel trucks, buses, and newer diesel cars can achieve efficiencies around 45% [4], however they could reach 55% efficiency in the near future [5].
The source documents seem to be little more than PDFs of PowerPoint slides, with them each giving contradictory information as to the actual levels of efficiency. Even accepting them as being accurate, it puts diesels on par with steam engines. (Which I've pointed out repeatedly are rated around 40%, a fact which you've thus far refused to acknowledge.) However, they are only able to do this with addition of lots of pollution controls. I'll note that as Leno's steamer proves, you don't need to have those on a steam engine, and that Wiki state's: (http://en.wikipedia.org/wiki/Doble_Steam_Car)
Its fuel consumption, burning a variety of fuels (often kerosene), was competitive with automobiles of the day,Which would, most likely, put it around 16 MPG, or so. Not bad for a vehicle with all the aerodynamics of a brick. This could no doubt be improved on with the use of modern materials and design. Too bad nobody with any money is willing to build one to find out if it could be improved. (The weight of the car Wiki says was "5000 pounds," which would put it slightly heavier than a modern fullsize SUV. Again, modern materials and methods could no doubt help this.)

So, what we've got is an "apples to orange" comparison, pitting a technology which hasn't been used in vehicles in over 40 years (in the sense that it hasn't had the same levels of research that diesels have), against a technology which has been heavily invested in and researched for the past 60 or so years. (The last time a steam car was seriously researched was in the 1970s as part of an EPA study. You can read a [10 meg] PDF of the Popular Science article on the car, as well as the fuel economy of cars being introduced that year here. (http://www.mediafire.com/?sharekey=c8142dd53429a545d2db6fb9a8902bda) The car beat the fuel economy of everything on the road, and the only one which came close was the much smaller AMC Gremlin. Unfortunately, there's no EPA documentation available. I know, because I've asked them about it, and they don't have it any more.) Not exactly what one would call "fair," is it?


So you are not certain that there are locomotives with efficiencies higher than about 10%, but you think there probably are some. Actually, I'm fairly certain there are. Could I tell you which ones, and where they're located? No. Would you believe me if I told you? Probably not. So what's it matter?


So our disagreement so far is this: You think there probably are steam locomotives with efficiencies greater than about 10%. I doubt that there are.If you want to characterize it as that, fine. I don't care.

HenrikOlsen
2008-Sep-02, 06:50 AM
Guys, take a break from this thread, both of you.

eburacum45
2008-Sep-02, 10:04 PM
I met someone involved in the Tornado project a week or two ago; they should be ready this year. It has only taken 18 years to get to this stage.

If anyone asks why we can't build a new Saturn V to go to the Moon, this project is an example of how difficult it is to replicate technology from the twentieth century once all the tools have been destroyed.

captain swoop
2008-Sep-02, 10:05 PM
One of the problems with conventional locomotive firebox and boiler designs is that at full power and blast up to 50& of the fuel is lost through the stack. On a mechanical stoker fed firebox the coal is blown in as a powder and up to 75% of it can be lost. It all ends up blown out in the exhaust and is either shoveled out of the smokebox at the end of the day or gets in your eyes as the train goes by.

captain swoop
2008-Sep-02, 10:09 PM
I met someone involved in the Tornado project a week or two ago; they should be ready this year. It has only taken 18 years to get to this stage.

If anyone asks why we can't build a new Saturn V to go to the Moon, this project is an example of how difficult it is to replicate technology from the twentieth century once all the tools have been destroyed.

Not quite. most of the time was taken up with fund raising. In an earlier pist I have listed a number of other projects under way to build replica engines.

There are several thousand preserved engines in the UK with about 700 odd in steam at any time. Thre is quite a an industry dedicated to keeping them running. Our sheds on the NYMR have a full time pro staff of engineers and we send locomotives away to dedicated engineering works that can build from scratch just about any component needed.

Money is the limiting factor.

eburacum45
2008-Sep-02, 10:20 PM
And a good job you make of it too. We'll have to set you to work building a Moon rocket...

captain swoop
2008-Sep-02, 10:36 PM
Some of the locomotives in the National collection won't be rebuilt for reasons of authenticity. For example the Green Arrow steamed on the NYMR last year but now it's boiler ticket has expired it will be left as is and put on static display. It has problems with a cracked cylinder block that to replace would mean a huge rebuild that would take away a lot of the originality of the last V2.