[Diy_efi] Turbine inlet & outlet pressures, housing A/Rs

[Greg Hermann]

At 6:45 PM 1/7/03, Grant Beaty wrote:
>Any idea where to get a banjo discharge?
>
>Thanks,
>Grant Beaty

I think you''d have to make one. There sure is a picture of a nice one in
McInnes' book, no clue where it came from.

Might try asking Turbonetics--

Greg
>
>----- Original Message -----
From: "Greg Hermann" <bearbvd at mindspring.com>
>To: <diy_efi at diy-efi.org>
>Sent: Tuesday, January 07, 2003 9:47 AM
>Subject: Re: [Diy_efi] Turbine inlet & outlet pressures, housing A/Rs
>
>
>> At 3:49 PM 1/6/03, Grant Beaty wrote:
>> >Oh Greg,
>> >
>> >Just saw some old posts of yours in the archives,
>> >http://www.diy-efi.org/diy_efi/archive/1999-January/msg00237.html
>> >
>> >> >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.
>> >
>> >Hugh McInnes states that increasing pipe diameter right after the turbine
>> >outlet will convert axial flow into turbulent flow. But in your post you
>> >don't seem to consider that as an option, instead opting for a banjo
>> >discharge. Is there any reason for that? Have you tried larger pipes
>without
>> >success? Any idea how much larger the pipe needs to be than the turbine
>> >inducer?
>>
>> A banjo would do an even better job of converting the spiral flow to
>> straight turbulent (less static pressure loss) than a step in the down
>> pipe, that's all. I think a step up from the exducer to the down pipe of
>> 3/4" to 1" is generally sufficient to shock the flow out of the spiral.
>>
>> The more of that static pressure you can recover (less shock loss), the
>> lower the effective outlet pressure is going to be at the turbine outlet,
>> and the less inlet pressure you will need.
>>
>> Greg
>> >
>> >Forgive my lack of understanding of your post, but are you suggesting
>that
>> >exhaust gas velocity post-turbine could be more than doubled by
>> >straightening the flow? Wouldn't that imply pressures < ambient? Or would
>> >total velocity out the turbine decrease, and more would go out the
>> >wastegate? Either is good, I guess.
>> >
>> >Thanks for any help,
>> >Grant Beaty
>> >
>> >----- Original Message -----
>> >From: "Greg Hermann" <bearbvd at mindspring.com>
>> >To: <diy_efi at diy-efi.org>
>> >Sent: Monday, January 06, 2003 10:56 PM
>> >Subject: Re: [Diy_efi] Turbine inlet & outlet pressures, housing A/Rs
>> >
>> >
>> >> At 7:21 AM 1/6/03, Grant Beaty wrote:
>> >> >Does anyone know how turbine outlet pressure effect the inlet
>pressures
>> >(TIP
>> >> >& TOP)? Does it work off of a pressure ratio like the compressor, or
>is
>> >it
>> >> >linear, and increasing TOP by 1 psi results in a 1 psi increase in
>TIP?
>> >>
>> >> Absolute pressure ratio, all the way.
>> >> >
>> >> >How about exhaust housing a/rs. Will a larger a/r always produce a
>lower
>> >> >TIP,
>> >>
>> >> Sure should.
>> >>
>> >> Higher EGT at the turbine inlet should require a bit lower pressure
>ratio
>> >> across the turbine to get the same shaft power (boost level at a given
>> >> engine rpm) out of the compressor.
>> >>
>> >> Greg
>> >> >
>> >> >Thanks for any help,
>> >> >Grant Beaty
>> >>
>> >>
>> >>
>> >> _______________________________________________
>> >> Diy_efi mailing list
>> >> Diy_efi at diy-efi.org
>> >> http://www.diy-efi.org/mailman/listinfo/diy_efi
>> >
>> >
>> >_______________________________________________
>> >Diy_efi mailing list
>> >Diy_efi at diy-efi.org
>> >http://www.diy-efi.org/mailman/listinfo/diy_efi
>>
>>
>>
>> _______________________________________________
>> Diy_efi mailing list
>> Diy_efi at diy-efi.org
>> http://www.diy-efi.org/mailman/listinfo/diy_efi
>
>
>_______________________________________________
>Diy_efi mailing list
>Diy_efi at diy-efi.org
>http://www.diy-efi.org/mailman/listinfo/diy_efi



_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://www.diy-efi.org/mailman/listinfo/diy_efi