This engine's design would be based off of the Scuderi split-cycle engine (see links), but would include a steam turbine. The power cylinder(s) of the engine would have an insulated boiler around it/them, which would power the turbine.

This combination of a Scuderi split-cycle engine and a steam powered turbine should be more efficient than a normal 4-stroke engine with a steam turbine, since the Scuderi engine would have a more concentrated heat output making the boiler much more efficient.
-- BJS, Mar 22 2007

How the Scuderi Air Hybrid Engine works http://www.youtube....v=Kogz4wedwtk&eurl=
On YouTube. [BJS, Mar 22 2007]

Scuderi Split Cycle Engine http://en.wikipedia..._Split_Cycle_Engine
@wikipadia [BJS, Mar 22 2007]

Scuderi's web site http://www.scuderigroup.com/
[BJS, Mar 22 2007]

Bruce Crower's Six Cycle Engine http://www.autoweek...1023/THISWEEKSISSUE
Modified diesel with direct water injection [discontinuuity, Mar 22 2007]

BMW TurboSteamer http://paultan.org/...1/bmw-turbosteamer/
extra power from waste heat [discontinuuity, Mar 22 2007]

Triple expansion steam piston engine http://en.wikipedia...#Multiple_expansion
On a steam engine page. [BJS, Mar 23 2007]

Hilsch Vortex Tube http://en.wikipedia.org/wiki/Vortex_tube
Could condense steam. [acurafan07, Mar 26 2007]

Would it still be considered a hybrid or 'tribrid' if it has only one actual fuel source?
-- BJS, Mar 22 2007


Still thinking about it, there is a lot to digest about the Scuderi engine. Based on an initial evaluation it has some intriguing possibilities as you have proposed it.
-- jhomrighaus, Mar 22 2007


Not only is this a good idea but you also found a way of including a youtube link. [+]
-- acurafan07, Mar 22 2007


I can't help but suspect that a Stirling engine would make more sense than a steam turbine.
-- IJK, Mar 22 2007


[IJK] Stirlings are not going to remove sufficient heat to be useful in this application(remember you still need to cool the engine primarily, the power generation is secondary. You need to dump heat for a Stirling to work which will kill any efficiency factors you might get) Though re condensing the steam is going to require cooling air flow as well, though less than for the Stirling idea, this might be any ideal application for those thermoelectric compounds somebody was talking about before.

Other wise the maximum performance for the steam is going to come over a maximum pressure differential through the turbine and the associated increase in volume of the steam(making it hard to recapture efficiently) Look at some info on Steam locomotives and the way they utilize steam. or look at nuclear power systems with steam generators and cooling towers. The problem is going to be cooling the water enough for reuse(while keeping the engine cool)
-- jhomrighaus, Mar 22 2007


Hmm...what about injecting water directly into the power cylinders, somewhat like a Crower six stroke?

Each power piston can operate in two different modes:

1. Diesel mode, where fuel is injected. This heats up the cylinder.

or

2. Steam mode, where water is injected. This cools down the cylinder.

In steam mode, the exhaust may be redirected to a recondenser.

This hybrid requires no steam turbine or boiler.
-- IJK, Mar 22 2007


This is a good idea, but I'm not sure if you would be able to get temperatures high enough to boil the water without damaging the engine or at least affecting its performance. You might have better luck with the BMW TurboSteamer design (see link), which scavenges heat primarily from the exhaust.
-- discontinuuity, Mar 22 2007


Wait what exactly do you plan to do with the power the turbine produces?
-- acurafan07, Mar 22 2007


I'd have it help power the crank shaft somehow, or the drive shaft directly.
-- BJS, Mar 22 2007


//but I'm not sure if you would be able to get temperatures high enough to boil the water without damaging the engine or at least affecting its performance//

I dont think this is the bigger issue, the hard part is going to be cooling the water enough to CONTINUE to pull enough heat away as the engine continues to run. Either a very efficient chiller will be needed or a large thermal mass to delay the water on its loop around the system. Either way there will still be a lot of heat to reject.

I think this could be combined with a turbosteamer type setup to retain the exhaust heat as well.
-- jhomrighaus, Mar 22 2007


Most of the water could possibly be stored away from the engine, and then go through smaller serpentine passages around the engine. Much like a conventional cooling system?
-- BJS, Mar 22 2007


Yes but you still need to figure out how you are going to recondense and cool the water enough to keep the temperature of the engine within a suitable range. Perhaps by adding a traditional radiator with a regulator of some sort that can kick in to maintain an acceptable temperature when needed.
-- jhomrighaus, Mar 22 2007


If you have a double or triple expansion steam engine, you will recover almost all of the heat energy in the steam before condensing it. The only problem with this is that it would cost a lot to build, especially with turbines. There is no real "free lunch" here, but if you are willing to spend more money on engineering, you can get some pretty incredible jumps in efficiency.
-- discontinuuity, Mar 23 2007


There would probably a semi-inexpensive way to rig something with a used turbocharger or ever used steam turbine off of ebay... Only problem is that there aren't many Scuderi Split-Cycle engines avaliable for testing it on.
-- acurafan07, Mar 23 2007


according to what i read the aren't any of them.
-- jhomrighaus, Mar 23 2007



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