turbine efficiency

[user removed]

http://www.innas.com/CFPE.html

DOE papers 10 years ago stated 58%.

Add a transonic injection system.

Transonic Combustion | Our Technology | TSCi Technology - Fuel Injection Systems

Now an accumulator at 98%

And one of these in each wheel, with infinitely variable displacement


http://www.youtube.com/user/Ride122609


There is your complete power train, with a huge reduction in power train parts count.


That's technology available right now, not some predicted development in the next decade.

Do a parts count on the moving parts in that free piston engine.

Of course I like my rotary flywheel engine better, with variable displacement and compression and no parts moving rapidly in opposite directions.


regards
Mech

[jamesqf]

Originally Posted by Old Mechanic

Chiron Free Piston Engine

DOE papers 10 years ago stated 58%.

That Chiron Free-piston Engine is hardly a standard IC engine, you know :-) Indeed, at a quick glance it looks like a variation on a Stirling engine.

From Internal combustion engine - Wikipedia, the free encyclopedia

"Most steel engines have a thermodynamic limit of 37%. Even when aided with turbochargers and stock efficiency aids, most engines retain an average efficiency of about 18%-20%."

[nmgolfer]

Originally Posted by bmwboarder

I too would love to see this in a normal car. I applied for a grant once to try and build a turbine car (out of a VW bug), but didn't get the grant I've been intrigued ever since though, as turbines run smoother (less vibration), with less parts and weight, more fuel adaptability, and higher efficiency. Using it to fuel an electric car seems to be even better too as the turbine could just spin at super high efficiency! Maybe use 2-100hp electric motors in the rear with one 20-40hp turbine supplying it... that would be a lot less weight than the jaguars huge electric motors, and turbines. I hope some car manufacturers are wondering the same thing. Do you think its just cost that is prohibitive? Or maybe the heat is still an issue?

Its been done... My co-worker in Seattle knew a guy who adapted a kerosine burning turbine JT somthing or other LOL... then there is the enigmatic Bob Lazar who has built at least two jet cars (Honda CRX's ) one of which was featured in the local paper when he was and employ at the meson physics facility at (then) LASL back in 1982.. And impressed Edward Teller so the story goes.

Bob's current business is here: United Nuclear - Hydrogen Fuel Systems

Anyway yes.... high power to weight ratio gas turbo-generators combined with electric vehicles would be an excellent marriage (low pollution with NOX production the issue). They could run on propane or N.G. or other liquid fuels (desiel) with slight mods.

About a decade ago (pre-melinium bug hysteria) there was a lot of interest in distributed generation using turbogenerators (not unlike the APU's which provide electricity on Jet Aircraft). Then Allied Signal (now Honeywell) had the Parallon 75 (kw) and Capstone in the LA area (which was former Allied Signal engineers I believe) has something similar. There was some talk of using them to power buses.

Neither took off for a variety of reason one of which being the Utilities (grid operators) not liking the idea of people producing their own power...

As for the heat... I don't think ceramics are quite there yet (but they might be) and they'd probably need inconel for the turbine or at least very good SS but I bet economy of scale could get the costs down.

Anyway... YES... I've long though the gas turbine (Brayton Cycle) is ideal for on-board recharging of E.V.'s It would be great to see

[nmgolfer]

P.S.

I believe the "micro" turbogenerator that would be ideal for on-board recharge (possibly some other configs too) could reach 40% using a recuperator... the remaining waste heat could keep the passengers toasty too.

[bmwboarder]

I think the premise of any tiny engine that only has to have a max of 30hp power and always runs at full efficiency would be cool. I wonder how much would get lost converting from gas to electricity and then being used by the electric motors though. Definitely a fun topic though

[nmgolfer]

Originally Posted by bmwboarder

I think the premise of any tiny engine that only has to have a max of 30hp power and always runs at full efficiency would be cool. I wonder how much would get lost converting from gas to electricity and then being used by the electric motors though. Definitely a fun topic though

Again... I think you could get close to 40% efficiency with a recuperator BTU -> Amps (lets say 35%) with tech. here today.. where as Fuel cels are about 40%. Beauty of a turbo-gen set is the simplicity... Generator and turbine share a common shaft.. spin-up >add heat (they're not picky from what... how about alcohol you brewed up in your back yard using yard waste?) and you've got plenty of juice for your batteries or electric motor(s)

Doubt Detroit will ever do it however... Big ships turn very slowly.

[gone-ot]

Originally Posted by nmgolfer

Doubt Detroit will ever do it however... Big ships turn very slowly.

...but, BIG ships can sink quite quickly (Titanic, etc.)

[nmgolfer]

This thread got me thinking about turbogenerators again, so I did a bit of googling.

First off that Jaguar is a neat vehicle and Tesla Motors should be concerned.. but I'm into fuel economy and practicality not show. Really... who needs nearly 800 hp (and all that torque) besides race car drivers?

The micro turbine(s) Jaguar used are indeed cool (looking like mini aircraft engines) but... any practical consumer automotive solution would use a single stage centrifugal compressor with the compressed air then passing through a recuperator before entering the burner and most likely expanding through single stage turbine. There should be no gearbox and the rotating assembly should be supported by air bearings. The unit should be sized to deliver a much smaller optimal load (really only need enough continuous hp to maintain cruise at highway speeds + a bit extra to recharge... the genset could continue operating after the vehicle is stopped to fully recharge and or provide power for other purposes). Also... the vehicle should be designed as a complete system where the intake air is used not only to cool the generator and electronics but is sucked from strategic locations on the auto body to provide boundary layer control to prevent separation thereby lowering the Cd. Likewise the turbine exhaust should be strategically expelled so as to enhance aerodynamics of the vehicle.

Anyway anyone familiar with these devices would arrive at the same conclusions and lo and behold... they have. Here's a blurb on a capstone 30 kw unit being installed in a Ford and delivering 80 mpg... (Not bad for a seven seat passenger vehicle) That's getting there! 100 mpg should be easily doable. (Obama ... don't let those oil industry embedded auto company execs tell you your piddly 50 mpg goal is pie in the sky!)

Capstone Turbine's Modified Ford S-Max Gets 80 MPG | Market News Video

I thought Capstone was kaput! I mistakenly figured they were history like Honeywell Power Systems when their stock tanked in the early 2000's... But they're still here! Their stock is selling for pennies but hey... The capstone turbines are great! Which ever auto mfg partners with these guys is going to have a huge advantage! I'm really happy to see they've survived the market meltdown(s).

Here is another capstone hybrid report:

Capstone Turbine CMT-380, Porsche Panamera ... - Car Videos on StreetFire

[bmwboarder]

More info on the CMT-380:
Update on the CMT-380 microturbine hybrid sports car — Autoblog Green
Interesting tidbit about how much the turbine price could come down.
Capstone Turbine Corporation | Press Releases | Photo Release -- Hybrid Electric Supercar With Microturbine Technology to Debut at LA Auto Show
"The Capstone C30 microturbine is so clean it does not require any exhaust after treatment to meet stringent clean air requirements of the California Air Resources Board or EPA 2010." -Cool!

Of course I would be much more interested in a 100mpg smaller car than a supercar, but I'm sure it will make the transition if it can be cost-effective.

[nmgolfer]

Yes... That car is a beauty! I wish America would get off the dime and lead in this direction. Mullaly (Ford ceo) grew up a Boeing was chief eng. on the 777 and should be very familiar with both reliability and advantages of APU type turbogenerators... why he hasn't out-right purchased capstone is beyond me but if I were in his inner circle I'd tell him:

"Allen... dude... this is a no brainer... what are we waiting for.. we need this technology!"

Only real issue is who owns what patents... I'm surprized Honeywell isn't claiming patent infringement on the air bearings... they developed those.

Anyway... yes... we should have an 100 mpg capable long distance driver that can run on Natural gas (preferably home refilled ) or desiel or alcohal or Hydrogen.... all clean burning and reliable as can be.

I'm going to visit Capstone next time I'm in so-cal.