Hyperbar

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Discussion

GreenV8S

Original Poster:

30,481 posts

291 months

Thursday 2nd January 2003
quotequote all
Came across a brilliant invention at the weekend, not original but new to me.

It's called a Hyperbar. The basic idea is to run a turbo as a free running jet engine. So you start with a conventional turbo installation. This would normally have a dump valve between the turbo and the engine, that bleeds excess pressure to atmosphere or back to the turbo induction inlet. In a hyperbar, the dump valve is fed into a 'beer can' combustion chamber where fuel is added and ignited just like in a jet engine. The exhaust from the combustion chamber is fed into the engine exhaust upstream of the turbo.

The end result is the turbine runs continuously producing any pressure you want (6 bar seems typical), powered by the engine exhaust when the engine is on power, and by the burner the rest of the time.

If you sketch it out, it's hardly any change from a conventional turbo installation. Apparently a French company used this in a diesel tank engine, and Nick Mann has one in a hillclimb special, but otherwise nobody else seems to use them. Now wouldn't that make an interesting project!

Cheers,
Peter Humphries (and a green V8S)

gbgaffer

546 posts

277 months

Thursday 2nd January 2003
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Hi Pete

Happy New Year. Re Hyperbar, isn't this a bit similar to the idea of that some the works WRC cars use; deliberately overfueling on over-run so that the resultant detonation upstream of the turbo keeps it spinning and presumably reducing lag by maintaining boost?

Does this mean you are planning to turbo charge the green machine?

Cheers

Graham

GreenV8S

Original Poster:

30,481 posts

291 months

Thursday 2nd January 2003
quotequote all

gbgaffer said: Hi Pete

Happy New Year. Re Hyperbar, isn't this a bit similar to the idea of that some the works WRC cars use; deliberately overfueling on over-run so that the resultant detonation upstream of the turbo keeps it spinning and presumably reducing lag by maintaining boost?

Does this mean you are planning to turbo charge the green machine?

Cheers

Graham



I think the big difference with normal anti-lag, is they only work on air that has gone through the engine, when you close the throttle this is shut off.

gbgaffer

546 posts

277 months

Thursday 2nd January 2003
quotequote all
Of course you are correct - had the brain in neutral.

Thinking cap on though, the control loop for maintaing 6 Bar must be interesting or do they overpressure and dump the excess whilst maintaining the turbine at a given rpm?

I'm having enough trouble working out how to wire in the ecu on my S

Cheers

Graham

GreenV8S

Original Poster:

30,481 posts

291 months

Thursday 2nd January 2003
quotequote all


Thinking cap on though, the control loop for maintaing 6 Bar must be interesting or do they overpressure and dump the excess whilst maintaining the turbine at a given rpm?




I haven't found anything saying how they do it, at a guess you might be able to use some sort of pressure switch to cut the fuel supply to the burner when the required boost was achieved. I imagine there's a fair amount of trickery involved though!

It would be tempting to do it just to see whether it actually worked!

Peter Humphries (and a green V8S)

plipton

1,302 posts

265 months

Thursday 2nd January 2003
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How about an electric motor constantly spinning the "turbo" at 200,000rpm? That would help with lag.

Once you've installed this set up on the green machine I'll be happy to test drive it for you

Johnny Freon

101 posts

263 months

Thursday 2nd January 2003
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Apparently the new GT-R will have electrically assisted turbos. I think I like that idea better than the hyperbar.

deltaf

1,384 posts

264 months

Thursday 2nd January 2003
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Ive seen a similar idea to this that was used to run a cart in the US.
The turbo was used as part of a jet engine design that propelled it to well over 100mph on propane!
If i can find the link ill post it here, but just cant remember it at the mo.