Water Injection Thread

[Greg Hermann]

>At 08:45 AM 1/5/99 -0700, you wrote:
>(snip)
>>I think the REAL unexplored gain is in (more efficient) pressure recovery
>>from the Mach .75 velocity in the gas spiral at the turbine outlet, though.
>>The circumferential component of the flow in that gas is distinctly greater
>>than the axial component. Some way of straightening the helical flow out,
>>and turning all (more) of that velocity back into static pressure would
>>truly be a FREE increase in the pressure ratio across the turbine, with all
>>of the performance improvements that that implies!!! Plus, I do not think
>>that a device for doing it would take up all that much space! Also, no
>>moving parts involved and decently low temps, so ALMOST as reliable as
>>taxes!
>>>
>>Greg
>
>  I was just reading about the "Banjo-type" turbine discharge, in Hugh
>MacInnes's Turbochargers.  On page 72 he states that Dennis Sevier, Chief
>Engineer of Bristol replaced an elbow, which cost power on acceleration
>and at top end, with the banjo-type fitting and found that it "worked at
>least as well as a straight exhaust".
>  Does anybody know where a feller could get a banjo-type fitting?

Nope, but I would be interested too!! I have been pondering on those banjos
too, also thinking about straintening vanes inside a backwards megaphone
with a cone inside, and some other ideas that would really cause a
fabricator to cuss loudly!!

All thoughts on this welcome!!

To give you all some idea of what I am talking about, on a 350 HP engine,
there is about 29 HP worth of energy just in the momentum (calculated above
the momentum of the gas in an exhaust pipe flowing at 200 fps.) of the gas
leaving the turbo turbine!!! (Not talking about heat energy here, just
momentum!!!) If you could recover just recover 60% of that , that would be
about a 5% improvement in output, essentially for FREE !!!

Let's get some ideas flowing!!

Regards, Greg