Yes it does add to the complexity of flying unless you want to
   get into microcomputer control of waste gates. So far I know
   of nothing like that off the shelf that will work with a turbo
   rotary in aircraft use.

   I think Gordon and maybe a few others on here have a turbo
   selection
   spread sheet for A/C use.

   Gordon, could you upload your spread sheet again?

   The thing to watch out for is turbine over speed. That makes
   car turbochargers the wrong choice for aircraft use as the car
   turbo
   charger turbine has too much HP for the compressor. This is
   done
   so the turbo charger will accelerate rapidly. In steady state
   use the turbo charger will over speed and the turbine will be
   destroyed. Several people have blown up stock turbo chargers in
   turbo
   rotary engines in aircraft use.

   Usually the turbo charged used is a TO4 for the 3 rotor but the
   compressor should be chosen to be larger than what one
   would find
   in car use. This slows the maximum RPM of the turbo charger
   to keep
   it within RPM limits for the given EGT. Another way of
   putting it
   from the turbine point of view is you want an A/R greater
   than one. This slows the air flow going into the turbine
   blades.

   A way of measuring this is record the temperature
   drop across the turbine. The higher the temperature drop
   the more powerful the turbine. Also it is a good idea to
   get a turbine tachometer to check and make sure the turbine
   RPM is within limits. This will pay off in the long run
   as your turbine will last longer.

   Here is a spread sheet from Dave Leonard.

   Also get a copy of this book.
   "Turbochargers" by Hugh MacInnes HP Books ISBN 0-89586-135-6

   To minimize oil coking use a synthetic oil like Idemitsu
   rotary engine oil or Mobile One. Also try to get a water cooled
   turbocharger housing. They are available for the TO4. The stock
   Mazda turbos are water cooled.

   Paul Lamar ...No rotor no motor.



   I'm not clear whether Don has p-port intake or not, and whether
   he is
   against p-port intake. If so, I don't really see p-port as
   being high
   risk at all, and might actually improve reliability by
   lowering
   temperature rise when boosted for a given horsepower
   produced by
   lowering pumping loses.

   As Paul has said, all rotaries until the Renesis already have
   p-port on
   the exhaust side..


   Matt-


   Paul and Don,

   Here's the Turbochart spreadsheet.

   If you have any questions about using it, or suggestions to
   improve
   it please let me know.

   I'm in the middle of completely revamping it to add the exhaust
   side
   so we can match turbines for turbocompounding. I also want
   to make
   it easier to use.

   Regards,

   Gordon.

   Thanks Gordon,
   This spread sheet is very helpful. As I started plugging in numbers for
   my 20B, I wasn't sure what numbers to use for the following:

   Volumetric Efficiency
   Air-Fuel Ratio
   Compressor Efficiency

   I sent the spreadsheet back in this e-mail with my number saved in it.
   Can you look at it for me? All my little colored boxes seem to fall
   outside of the graph. The GT4202 Turbo Chart seems to be closest since
   the colored boxes are at least inside the graph. Am I doing it right??
   What does all this tell me?
   Don



   It is good to see that both mine and Gordon's calculators are coming up
   with about the same numbers. I was a little more conservative on the
   volumetric efficiency. Don't for get that you particular manifold will
   play a big role in that aspect as well.

   Either way, modest boost at higher VFR altitudes is going to give you
   55-60 lbs and a little more than 2:1 pressure ratio.

   None of those Garrett turbos are big enough. Take a look at the
   turbonetics turbos I sent... puts you right in the middle...

   I know Garrett has some big turbos too, I just don't have any of
   those maps.
   --

   David Leonard

   Turbo Rotary RV-6 N4VY
   N4VY.RotaryRoster.net
   www.RotaryRoster.net
   leonardiniraq.blogspot.com


   Dave,

   I'm going to add some bigger Garrett maps to my spreadsheet. It was
   only really meant for the 2-rotor. There are much bigger turbos in
   the Garrett catalog.

   I've been checking out your spreadsheet and it is nicely done. Mine
   doesn't have the exhaust side yet, which is what I'm working on now.
   I may have a couple of questions about the exhaust side formulas you
   used.

   Regards,

   Gordon.

The Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://www.rotaryeng.net
Copyright 1998-2006 All world wide rights reserved.