Welcome! Log In Create A New Profile Recent Messages

Advanced

turboelectric vehicle

Posted by Ed Ferris 
turboelectric vehicle
April 05, 2019 08:23AM
Has anybody (in history) tried a vehicle with a steam turbogenerator feeding an electric traction motor? With a battery, like a hybrid ICE vehicle, it would solve the problems of starting torque, getting power from a tiny turbine rotor to the drive wheels, and using high steam expansions without multiple cylinders. I have heard that it was tried on a railway locomotive in the 1960's, but the waste heat would melt the pavement on overpasses.
Again, with a battery to fill in, there would be no necessity for reserve steam, and a Serpollet hot-surface flash boiler could be used. As they used to sing, "See the USA / In your Serpollet".
Re: turboelectric vehicle
April 05, 2019 11:23AM
As Jim Crank would say "Energy systems in series, I don't think so" smiling smiley

I do believe that if a modern steam car is ever a player it will be a hybrid of some sort and using some sort of heat derived by elements that cannot be used any other way i.e. gasified. The internal combustion engine in a standard size motorcar is always going to beat an external combustion engine for economy and performance. Some of the little cars weighing near 3000 pounds are getting near 50 miles per gallon, my little steamer weighs barely 700 pounds and gets around 18 mpg, with a fairly efficient boiler and burner.

However in a hybrid like this, it's doubtful a turbine would work well, "would melt the pavement on overpasses." is a clue, it's throwing away massive amounts of heat. Efficiency is all about the heat and how it's used.

-Ron
Re: turboelectric vehicle
April 05, 2019 11:41PM
I have never seen any evidence of somebody trying a steam turbine/electric/battery hybrid drive system in road vehicles. Steam turbines have a scale issue; big ones can be way more efficient than comparable piston engines; small [car sized] steam turbines are actually less efficient than reciprocating steam engines.

But maybe it's worth trying?

Starting torque is not a problem with properly-designed car-sized reciprocating steam engines; they are easily designed to exceed the traction limit of car tires at low vehicle speeds. Great for "burning rubber".

Many years ago, I used to pontificate/preach about how modern 4000 lb modern pickup trucks get the same fuel mileage in ordinary driving as 4000 lb 1920s Stanleys. I always had secret doubts about it though. Then, for the past several years, I have driven a 4000 lb modern pickup truck, 2016 year model, with VVT, cylinder deactivation, fuel injection, total microprocessor control, 8-speed computer controlled automatic transmission, and all the most advanced/efficient modern internal-combustion-engine road-vehicle propulsion tech available. The little computer screen on the instrument panel constantly shows me fuel mileage figures which exactly match the dozens of reports which I have read over the years for 1920s Stanleys of comparable weight -- and higher air & tire drag, which "should" guarantee better modern-gas-truck fuel economy relative to the old Stanleys, even if the net thermal efficiency [fuel to tires] of the 1920s Stanley were the same. Obvious conclusion: the 1920s Stanley powerplant is more efficient than the 2016 V8/Otto engined rig. Obvious to me, anyway.

I don't doubt any more, but I also don't preach any more. Car powerplants are like religion and politics, matters of faith and identity. There is a good reason why these were always traditionally treated as things "not to be discussed in polite company". Preaching something different from what somebody is already "emotionally invested in", is just going to offend them, and will be automatically ignored/rejected, waste of time. So my current thing is, don't "preach" -- design/build/test/demonstrate it instead. "Believer" types will always quibble with even the best test evidence; "thinker" types _might_[?] change their minds if new evidence pops up. Both ignore preaching.

The same goes for the issue of solid-biofuel-gasogene/IC versus solid-biofueled steam cars. I have seen reports of the former being more efficient than the latter, but I have also seen lots of contradictory reports/analysis. My view is, the heck with debating it on the internet: design/build/test, and find out the actual road results first hand.

Reminds me of the old joke about the guy who searched the world for the answer to "the ultimate question of life, the universe and everything" [a la Douglas Adams' "Hitch-Hiker's Guide To The Galaxy"]. Finally, after vast struggle, he climbed far into the Himalayas and found an ancient wise man who lived in a cave, far up in the remotest mountains. "What is the meaning of life?", he asked the venerable Holy Man. The Holy Man thought for a while, then said: "The meaning of life is... a tree."

"A _TREE_???", said the Seeker.

The Holy Man thought a while longer. Then he said, in a stereotypical Thoughtful Old Rabbi accent, "I could be wrong?"

Badum-bump.

Thank ya ladies and germs, you're a wonderful audience. I'll be here all week. Try the chicken.

Peter
Re: turboelectric vehicle
April 06, 2019 11:48AM
YES !!!!


Image of motor

notice these patents Self cooling motor system

self cooling motor system

I am the author of this patent, it can use water or freon to cool the winding's of the armature, Using centrifugal force so no pump is needed for circulation. meanwhile you have immediate torque to drive the vehicle with 12volts power electric motor (its about the size of a 5 gallon bucket. As the motor runs the windings are cooled and steam may be produced that can power an auxiliary generator. This not 1 to 1 or overunity...

The construction is difficult but it will do exactly what you describe.



Edited 4 time(s). Last edit at 04/06/2019 12:09PM by Jeremy Holmes.
Re: turboelectric vehicle
April 06, 2019 12:35PM
Agreed, theorizing is pretty futile. All sorts of practical angles you don't realize until you actually build an engine.
It could be that a multiple-reentry turbine (like the Terry) would have enough stalled torque to be used without a clutch. Or if not, just use a clutch and flywheel.
Re: turboelectric vehicle
April 06, 2019 12:57PM
Doesn't surprise me that my post is overlooked, happens all the time.
Re: turboelectric vehicle
April 06, 2019 01:37PM
This is just a exercise in people asking about a subject that they have no practical idea about how it would be actually constructed
Re: turboelectric vehicle
April 06, 2019 03:12PM
Mr. Holmes: I did not ignore your reply, I just don't see how your liquid-cooled motor is relevant.
Sure, I won't know how practical or efficient the turboelectric is until I build it, in a lab version at least.
How does a Terry turbine compare to a reciprocating engine for stalled torque and low-speed efficiency (inefficiency, really)? They were used to run auxiliary machinery such as blowers in the US Navy, but you don't need lots of starting torque for a blower. Anybody know?
Re: turboelectric vehicle
April 06, 2019 03:32PM
Thanks for the reply Ed. The idea is that a electric traction motor has full torque from battery's and has good driveability. Years ago there was the EV 1 that used DC current to run. It was soon decided that a DC traction moter overheated. Then came the second generation AC traction 3ph drive transmission. This is what one out for the current generation EV's... But overheating was controlled by the high voltage squirrel cage motors.

I am a ASE L1 Master-tech and designed a DC traction motor and went so far as to patent the design. I know it will work because DC traction motors overheat. If you can water cool the armature windings as there spinning in the motor you can obtain maximum torque.

I like the idea of high torque DC components. I also designed a DC injector valve with variable lift for throttling for steam injection systems on a piston engine. US 7,552,715 [flashsteam.com]

Ive been at this for a while, god only knows how much I spent on this development so you will have to forgive me for getting personal.
Re: turboelectric vehicle
April 06, 2019 03:54PM
Ed,

Your idea sounds interesting. Concern over starting under load could be resolved with a torque converter similar as used for an automatic transmission. And of course too, there is really not much load on a generator until the RPM/voltage output exceeds battery voltage.

The contemporary wisdom is small steam turbines are very inefficient compared to their piston powered rivals. A buddy of mine is working on a small steam turbine for a steam bike, so far it looks as though it is going to work, but I think it's going to consume a large amount of steam for the power output.

Like most things, won't know until it's tried

-Ron
Re: turboelectric vehicle
April 06, 2019 08:16PM
[www.youtube.com]

I know Peter will get a kick out of this
Re: turboelectric vehicle
April 07, 2019 02:24AM
Jeremy, Congrats!! It takes a lot to get a patent as some here know (I don't know how many here have been through this process) . It took almost 3 years for my brother and myself to get ours. I want to give this a closer look when I'm wider awake .

SteveW
Re: turboelectric vehicle
April 07, 2019 05:16AM
You know me too well Jeremy; yeah I liked that.

[www.youtube.com]

"The Truth Is Out There"; "Roswell! Roswell!"

LOL

Getting back on topic for a moment smiling smiley, I think Ed's idea might have some promise for _high-performance_ sports cars. Nobody cares about powerplant cost or efficiency with those. Maybe big turbine, compact/powerful steam generator with simple on/off control [instead of tricky variable-output monotube controls, which need heavy tube stacks/high-hysteresis for good results], and something like today's "performance EV" tech for the final drive, The turbine might be off the shelf, and with a series hybrid setup it would kick on now and then to whizz up a quick charge/discharge battery [or perhaps "utracapacitor"] pack, driving low-heat superconductive motors. The battery would use coolant/radiator system to handle the charge/discharge heat load. Once upon a time, EVs were just a rechargeable battery pack and direct-drive motor. Now they're all battery-coolant/radiator, change-speed multi-ratio automatic trans, ultra-sophisticated microprocessor control and so on, all the complicated energy-wasting expensive equipment which EV'ers & EV/IC hybrid guys used to brag about the "inherently simple/inexpensive/efficient" electric car not needing. Then they discovered just how tricky wildly-variable-load/speed automotive drive systems have to be; cost/simplicity still favor the traditional steam car.

Ron & Jim Crank's comments on "energy systems in series" are still pretty fatal to hybrid system efficiency, but if it's a high-performance vehicle, nobody cares. I recall reading about how a "Bugatti" [VW Group] Veyron, and similar supercars, completely empty the fuel tank and require a 4-wheel tire change after ONE full-speed run. There is a very small but potentially profitable market which has no problem with this. VW Group reportedly lose money on each Veyron they build/sell, however. It is strictly a prestige/flagship/publicity stunt. But some other "over the top tech" performance car makers reportedly turn a profit in this rarefied top-shelf market segment.

Whatever you do, "build something wonderful". And be safe, and have fun.

Peter

===========================

Odd video that turned up during that youtube search, brought back memories of strange trippy adventures in my Old VW in the SoCal desert, back in the old days:

[www.youtube.com]



Edited 2 time(s). Last edit at 04/07/2019 05:44AM by Peter Brow.
Re: turboelectric vehicle
April 07, 2019 12:02PM
I own a "performance EV" and the performance is incredible. The motors are cooled as is the battery. In fact cooling is what limits performance. In performance mode fans provide extra cooling, but there's still a limit to the time, set by battery heating, you can get full power.

Essentially you are replacing most of the battery with a steam turbine power plant. I would think the steam power plant could be lighter, but maybe not. There's no question the steam power plant would be less efficient in converting the energy in the fuel to power than a pure electric vehicle. The small steam turbine power plant is competing with big central power generating plants. There's no way it could be more efficient. That might not matter in a performance vehicle, though.

Lohring Miller
Re: turboelectric vehicle
April 07, 2019 02:44PM
.



Edited 2 time(s). Last edit at 04/08/2019 08:50PM by Jeremy Holmes.
Re: turboelectric vehicle
April 07, 2019 03:27PM
A 70hp Terry turbine, now listed for sale, weighs 3250 lbs. H'm. I hope that is merely lots of cast iron for a stationary application.
Yes, a central generating plant can be 40% efficient, but there's no good way to store electric energy in a car. My Prius has a 2.5 kWhr battery; you need 16 kW continuous. Tesla says their battery pack is 100 kWhr.
Re: turboelectric vehicle
April 07, 2019 10:16PM
Ed,

I like your idea and it looks like you've put some thought in it from an engineering perspective. We can editorialize, but as I mentioned above, won't know until it's tried or at least some testing is performed.

I occasionally think about a modern steamer, nothing too radical, very light weight, high output boiler with compounded piston engine with electronic control of cutoff etc. I'm pretty sure it would be nothing more than a novelty as it would pale in comparison fuel efficiency-wise to the modern diesel. It would have some clean air standards appeal.

If you have some ideas along these lines, I for one would be interested in reading about them.

-Ron
Re: turboelectric vehicle
April 08, 2019 04:37AM
I agree with Ron; as Tony Grzyb says, "you don't know till you build it".

Two things to add to that. One, as Ken said once, even if it's built and tested, we still might not know absolutely for sure. Some relatively small mistake in design or fabrication could give bad results, which would not necessarily be inherent to the design concept. I read in the SACA magazine recently that one of the Williams engines had an overlooked casting defect which messed with its performance.

The other thing is the incredible complexity of automotive propulsion systems. Even in a "simple" steam engine with only a dozen or so moving parts, there are a zillion things going on inside the cylinders under varying driving conditions.. Temperature & pressure vary all over the place, then there's surface losses, initial/warm-up condensate, cold running, residual exhaust recompression, lead, effective versus nominal cutoff, flow resistance, windage, heat conduction between various parts, complex interplays between the factors, and so on. Then all the alternative steam engines, and all the other types of car propulsion systems, and all the variants of the different types of systems, all have their own different sets of zillions of things going on inside. Then there are about a zillion different drivers, each with his or her own amount and type of driving, budget, needs, preferences, and so on. For just one example, I could have gotten the FIAT commercial diesel in my truck, and would be getting 30mpg on the highway instead of my current 15mpg or so with the gas V8. Twice the fuel mileage is always better, right? But I drive so few miles a year, and so much of it at putt-putt stop/go speeds on surface streets, that the fuel savings would not have paid for $6000 extra engine price over the service life of the vehicle. At the same time, the salesman said he had another customer who puts 200,000 miles a year on his truck, and for him the diesel is well worth the extra engine cost.

With all the complex factors involved, I don't think anyone has the time to find and analyze all the information, let alone explain or debate the analysis of "what is the best car". [and btw is there "a" best car, or "the" best car? Best in what way, and for whom?] Thousands of pages could be written on the subject, over endless years, and there would still be more issues and tradeoffs left to discuss. In the future I think there will be vast Artificial Intelligence machine brains which can process many orders of magnitude more info than any of us can. But even they will lack information, even if we end up with an undesirable total-surveillance "panopticon society" a la George Orwell. So even then, build and test will remain the best approach. This has historically worked out very well, providing lots of different vehicles which are very useful and enjoyable for lots of different folks. There are even a lot of "oddball", "curio", and even "lemon" cars, which have their own very devoted fans -- EG, "you can take away my Trabant when you pry my cold dead fingers off the steering wheel". LOL.

So yes, build and test different stuff, plus of course do some homework on what looks likely to give desirable results. And if the vehicle ends up good for you, then odds are there's lots of other people who will like it too.

Peter
Re: turboelectric vehicle
April 08, 2019 05:49AM
A while back there was a question about Terry turbine efficiency. From my time as a Navy Machinists' Mate, I can tell you that the efficiency sucks. Terry turbines are used in naval steam systems for auxiliaries because they are very rugged and because the steam consumption of these systems wasn't that great a proportion of the whole. (well, they were used but they had gone out of favor even before steam plants started to disappear) The exhaust steam could be used in places like the RPSS (Reduced Pressure Steam System) which provided heating steam for the distilling units, fuel preheaters, ship hotel services and the like. Since the exhaust has productive uses it wasn't really a "loss" and the low efficiency was tolerable.

In smaller sizes, a radial inflow turbine is probably the most efficient alternative. (see the turbocharger under the hood of your car). These get pretty largish as I've seen them on helicopters. Note that turbine efficiency curves are pretty "peaky", they have a certain speed they really favor. Theoretically, the peak efficiency for a turbine would occur when the turbine tip is turning at 1/2 the steam spouting speed. Of course, that's also a physical impossibility for a number of very practical reasons... most of them similar to the reason you can't have a boat propeller with zero slip.
Re: turboelectric vehicle
April 08, 2019 09:03AM
Back to electric cars. The battery in my Tesla holds the energy of between 2 and 2.5 gallons of gasoline. That much electricity costs at least as much or more than the gasoline. However the car goes as far as My Subaru BRZ did on around 9 gallons of gasoline. That's plenty for my 120 mile weekly commute, even in fun mode over hills and along curvy roads. Its electricity here comes at least 50% from wind turbines and hydroelectric dams.

One of my staff owns 3 horses. I'm afraid steam cars are in the same category with IC cars soon to follow. They each were great engineering (breading in the horse example) examples of the best technology of their time. What is practical for regular transportation changes with current technology. Like most of you, I have loved the piston engine in all its forms since high school. That's been over 60 years. It's not the future.

Lohring Miller
Re: turboelectric vehicle
April 08, 2019 09:06AM
Thank you for the informed opinion on Terry turbines. Also for the reminder that a turbine can be small and light enough to be used in a vehicle, the same as turbochargers are.
Many years ago I had a friend who had an auto-repair shop across the street from what used to be the Doble factory in Emeryville and was now owned by Besler. Besler himself never showed up, but we talked with the mechanic who was there and inspected the two conversions he had done. He said the steam just flowed right through the engine at low speeds. So there is room for improvement in the traditional design. The inefficiency of long cutoff in a recip engine would not be acceptable in stop-and-go traffic. And for saving energy by not idling, well, my Prius doesn't idle much either.
Re: turboelectric vehicle
April 08, 2019 11:51AM
I deleted it.



Edited 2 time(s). Last edit at 04/08/2019 06:47PM by IronChief.
Re: turboelectric vehicle
April 08, 2019 06:09PM
I am curious about the Terry turbine. Did some research here's what I found

Terry turbine
Re: turboelectric vehicle
April 12, 2019 06:41AM
"One of my staff owns 3 horses. I'm afraid steam cars are in the same category with IC cars soon to follow."

Yet lots of farms make a living breeding and selling horses, many shops make a living producing horse-related equipment; there are even profitable shops which build & sell "long totally obsolete" horse carriages. Hot air balloons, propeller airplanes, sailplanes, and hang gliders are "outdated" compared to jet planes, yet those are all in profitable production -- many after decades of being "extinct". Sailboats are less capable than powerboats, yet still in profitable production. Hot rod shops make a bundle pumping out barely-updated [& usually horrendous-mpg/big-engine] 1920s/30s custom IC cars. And so on.

Yet steam cars are far more capable & useful than horse buggies, and there are still no new ones in production.

Gas turbines, Wankel engines, etc were once widely believed to be "the car engines of the future", obviously inevitable replacements for the old piston engine, yet never happened. The jury is still out on EVs; far too big a topic to get into here. I will say that I have studied it extensively and personally see serious grounds for doubt. But, again, the jury is still out.

"Nothing is written" -- T.E. Lawrence

One thing I notice is that developers of EVs & other alternative car powerplants don't spend time arguing against steam cars. Instead, they work on the technology which they believe in and know. I think it is fair to return the favor. Personally, my goal is to be a steam car developer/builder, not an "EV critic" -- or "IC critic" or other critic. There's still only 24 hours in a day, and as Coburn Benson once said, "TIME is of the essence". There are plenty of EV critics/skeptics [and advocates] out there if anyone is interested in the issue; many with extensive automotive engineering & business, and even EV-R&D experience; no need for me to repeat their views and many reasons [esp. limited time] for me not to. Google it.

I have no problem with people who buy, drive, and/or develop/build EV's. Buy, drive, and R&D what you love. If you love it, then I am happy for you. R&D, production, and buy/drive are how progress happens.

Peter

========================

Internet debates, on the other hand, usually end up more like this:

[www.youtube.com]



Edited 6 time(s). Last edit at 04/12/2019 07:22AM by Peter Brow.
Re: turboelectric vehicle
April 12, 2019 08:17AM
The determining criteria is how many vehicles you wish to build and whether these are private ventures or 'for sale'. The production of motor vehicles in any significant quantities is highly regulated. It is necessary to meet a huge array of standards -- emissions, fuel economy and safety being the most noteworthy. When working at the Mid-Sized Car Division during my apprenticeship we had to built different variants of the same vehicle for different countries. Mostly these differences were regulatory. Human eyes work differently in one country over another and therefore they all have different standards regarding headlights. Same with fuel filler spouts and so on....

If looking at a production vehicle, the designer has far less freedom than people suppose. A very large portion of the design options are already set by government regulation and the trick is to incorporate your own technology while staying within the confines of the law.
Re: turboelectric vehicle
April 12, 2019 10:09AM
Manufacturing is orders of magnitude harder than making one or two prototypes. I race model boats where electric power is slowly taking over from IC power. The major IC power competitor for these boats comes from mass produced industrial engines. It's very hard to beat the costs or quality of something that's made by the tens of thousands. The same is true for cars. EVs have just started to be made in quantity. There is a huge sunk cost in IC engine production equipment at the major car manufacturers. The transfer lines and other automatic machines are amazing and expensive to junk.

Back to turbo electric cars. I think you need to consider the electric part as the transmission. Why not use one of the modern constant velocity mechanical transmissions? Gearing down the turbine rpm to a suitable rpm for input would be simpler and lighter than the electric version in small sizes. I don't know any examples of electric transmission smaller than locomotives and ships. It's too bad Jim Crank isn't around to explain how he coupled the turbine in his land speed record car. A clue to what his Lear turbine powered car power plant looked like can be found in this discussion.

Lohring Miller
Re: turboelectric vehicle
April 12, 2019 11:06AM
I'd suggest looking at the energy recovery turbine which has been found in some Formula One race cars. They use the standard idea of a piston engine (which, compared to a turbine, is wonderfully suited for power delivery across a wide rpm band, especially when heavily turbocharged). The high turbo boost results in extraordinary power density but also results in high exhaust pressures, which are very wasteful. A radial inflow turbine mounted on the exhaust is affixed to a high speed alternator which, in turn, powers an electrical drive setup that works in tandem with the ICE transmission. (The turbo also drives the turbo compressor while the parallel electric motor can offer regenerative braking). They have reported thermal efficiencies of 45%, somewhat better than the average Diesel. It takes a beefy engine to pull this off, but it can also be quite small. There have been suggestions of powering cars with two cylinder engines, very high boost and heat recovery turbines. Given that this technology is actually operational, the only requirement is development for a suitable mass production variant.
Re: turboelectric vehicle
April 12, 2019 04:02PM
Inserts foot in mouth...

Quote
lohring
Back to turbo electric cars. I think you need to consider the electric part as the transmission. Why not use one of the modern constant velocity mechanical transmissions?

When I was an active member of SAE I saw the innovations to hybrid cars they found a way to drive the car using 3 phase AC synchronous motor built in the automatic transmission built into the clutch packs. In this way the designed system was compact and easily cooled using ATF. when driven by the IC engine was no problem Although the electric component was/is high voltage. There is no problem transferring the electric auto trans mode to ICE and the system.is compact.
Re: turboelectric vehicle
April 12, 2019 05:25PM
What I was thinking of is a series hybrid, where the drive is always through the electric motor. The turbine would be turning at 10,000 rpm, because we need a very small casing (unlike the 3250 lb. Terry turbine I mentioned), and I don't see any practical way of connecting it mechanically to the drive wheels.
A turbo-compound steam engine is interesting, because the exhaust turbine (after the recip first stage, which drives the car) would be compressing steam with some of the energy which would otherwise be thrown away in the condenser. Still, I would only expect less than a 5% increase in overall efficiency. The change from 200/1200 BTU/lb to 200/1000 BTU/lb is only 1/6 to 1/5, a 3-1/3% gain, which is 6 mpg at the best.
Re: turboelectric vehicle
April 21, 2019 06:21AM
IC cars, and battery-electric cars, and ,IC-electric hybrid cars, will become extinct. Traditional steam cars, with Stanley-like engines, will replace them.

Peter



Edited 3 time(s). Last edit at 04/21/2019 06:31AM by Peter Brow.
Sorry, only registered users may post in this forum.

Click here to login

All files from this thread

File Name File Size   Posted by Date  
Motor with Gearbox.JPG 498.4 KB open | download lohring 04/21/2019 Read message
01a.pdf 31.1 KB open | download Jeremy Holmes 04/27/2019 Read message
oil1.pdf 17.6 KB open | download Jeremy Holmes 04/27/2019 Read message
oil8.pdf 18.9 KB open | download Jeremy Holmes 04/27/2019 Read message
oil10.pdf 33.4 KB open | download Jeremy Holmes 04/27/2019 Read message
2018 Cruze TD panel1.png 115.8 KB open | download frustrated 05/06/2019 Read message