From: shipchief@aol.com <shipchief@aol.com>
Subject: [FlyRotary] Re: Turbo Questions
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Date: Wednesday, August 25, 2010, 1:25 AM

ANOTHER TURBO QUESTION:

What about turbo insulation. Dave Leonard, you mentioned it before, and I listened. Now I'm ground running (3 hours!!) and under cowl temps after shutdown seem high. I have the Van's foil sheeting on the inside of the cowl anywhere near the turbo, a sewn insulation cover for the turbo that Dave said would be insufficient, and some kevlar-like welder's drop cloth in a single wrap around the turbo down pipe. The turbo header is bare with an aluminum heat shield to keep direct radiant heat off the motor mount and lower intake manifold. I'm afraid to insulate the header,as rotary exhaust temps are challenging to 321 stainless steel.

Right now, I open the oil door to let heat out after ground runs, and before addition of the foil, I used to run the shop vac discharge hose in the cowl to move some air too. I need a solution that would allow flying to another destination, not just back to my hanger where a fan can cool the under-cowl area so the fiberglass doesn't melt.

Any practical advise?

 

-----Original Message-----
From: Kelly Troyer <keltro@att.net>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Sat, Aug 21, 2010 9:10 am
Subject: [FlyRotary] Re: Turbo Questions

  The only possible downside I can see is turbine over-speed at altitude.........Part of this equation

is based on what rpm your engine will be turning at takeoff and cruise, the altitudes you fly and

the psru ratio you have (2.17 or 2.85) with the 2.85 probably averaging 600 to 1000 rpm higher 

for both takeoff and cruise (fuel flow concerns may also be a personal factor)..........Also your prop

is a factor depending if it is fixed pitch or constant speed (or in-flight adjust such as my "IVO").......

 
   With an adjustable pitch prop you can load the engine at a lower rpm and control turbo boost

with the throttle while being careful to avoid detonation.........The bottom line is only flight testing

can determine exactly how your turbo will perform in your particular installation..............Should

your .81 a/r ratio turbine housing be a little too tight a .96 a/r ratio "On Center" housing to fit your

"P" trim (F1-65mm) turbine wheel is readily available for less than $300.00 and the .96 housing is

 working well for John Slade and his "IVO" equipped "Cosy" ............ 

 

  Let the group know how all is working once you get her in the air !!.............FWIW

 

Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold

 

 

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From: "shipchief@aol.com" <shipchief@aol.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, August 18, 2010 6:46:46 PM
Subject: [FlyRotary] Re: Turbo Questions

Correction!!!

I just checked my aircraft manual, and the Turbo has a .81 AR. That's pretty tight for this group discussion. I guess we will see what happens as I run my engine at higher power.

 

-----Original Message-----
From: shipchief@aol.com
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, Aug 18, 2010 3:49 pm
Subject: [FlyRotary] Re: Turbo Questions

George Kelly and all;

I've been off the list for a while (work) but today I safety wired the water pump pulley bolts, as discussed in  'one thing leads to another'.

Then I ran my engine for 40 minutes @ 1900 RPM. The low voltage that alerted me to the pully bolts was still with me, so I ran the engine with the upper cowl off, and climbed out of the cockpit to have a look.

I always sat in the plane while running it before, so this was pretty informative. I ran it for a while, more than 20 minutes watching the battery voltage slowly drop to 11.9 volts, still the engine ran sweet. I checked alternator output; it was just battery voltage, so nothing. I hooked up a battery charger and kept running so I could watch the belt, feel the intake manifold and turbo etc. and look for problem areas. I'm feeling good about my installation becuase it looks fairly neat and runs smooth and sweet. I'm beginning to feel that this is going to be a success story. wink, wink, Tracy. I just need to finish the airplane ;)

About the Turbo:

I'm running a 60-1 P trim compressor and .97 AR On-Center TO-4 turbine housing ( if I recall correctly) with a water cooled bearing. I built the exhaust manifold simply because the Fred Brease mount I bought would not accomodate the cast iron Mazda Turbo manifold.  I selected the On-Center turbine because I wanted the design flexibility it offered, and in fact I was able to mount the turbo with the exhaust oulet facing aft. The down pipe is very short, the intake filter is directly on the turbo compressor, and to finally get to my point, my turbo is direct mounted to the engine with a very short but somewhat large volume 321 stainless manifold.

I decided to give up all the waste gates, blow off valves, remote mounts, flex joints, etc. and followed Kelly Johnson's addage: "Add Lightness and Simplicate".

I installed the battery in the back of my RV-8 because RV-8's with Lycoming IO-360 & constant speed props need to do this for CG reasons. I couldn't imagine my 13BT being lighter. Still, lightness is required, so I work at it. All those accoutraments have there place, and maybe I will end up needing some or all of them, but I decided to start with none of them and go forth. I'll add what ever I end up needing.

My turbo air pipe is somewhat long, but it does pass by the left side of the cowl where I could mount an intercooler with air exit, so I have that as a possibility. If I need a waste gate, I'll just cut a hole in the exhaust manifold and TIG weld in a bypass pipe with or without some kind of valve....I have a spot in mind for that too.

I may be over thinking this whole thing, and that is part of why I build so slowly.

But I do have 2.5 hours on the EM-2 hobbs meter!!

 

-----Original Message-----
From: George Lendich <lendich@aanet.com.au>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, Aug 18, 2010 2:03 pm
Subject: [FlyRotary] Re: Turbo Questions

 Kelly,

Let us all know how well it goes for you in the real world application. I can't help but feel we are trying to fit a square peg in a round hole with Turbo application to Aviation needs.

 

Personally for myself, as I have stated before, I feel that I would use remote mounted turbo, like some cars use (to reduce the heat and flow speed to the turbo) and feed it from a bypass off the exhaust pipe. The by-pass could be controlled manually, for (when required) application. A wastegate does the same thing but the exhaust is taken right up to the turbo and carries the heat with it. I think this would go a long way in controlling heat and over spinning issues.

 

However you need the necessary room to make this possible.

George (down under)

Bob, John and All,

 

     Well I have bit the bullet and made my decision for a turbo............After much research, talking to Bob

and John and conferring with a "Turbonetics" dealer I have ordered a TO4E-50 trim (compressor wheel),

wet bearing housing, big shaft "Q" trim (F1-68mm) turbine wheel and 1.15 a/r ratio turbine housing.........

 

     The decision what size turbine wheel and a/r ratio housing was based on the fact that the f1-68mm

turbine and 1.15 a/r housing causes less exhaust back pressure than the smaller wheel (bigger hole) and

will increase rpm less as you increase altitude as opposed to the F1-65mm wheel plus the 1.15 a/r ratio

housing will slow rpm increase for the same reason............

 

    The decision to go with the 50 trim compressor wheel (Like John) verses the 60-1 wheel (Like Bob) was

based the "Flow Maps" of both wheels and my uneducated opinion that the 50 trim wheel would be running

in a more efficient area of the flow map base on the "Air Consumption Chart" (lbs per min) of the 1.3L 13B

that I submitted to the group in a previous post.............Of course for all practical purposes there is probably

little discernible difference between any of these turbo configurations mentioned.............

 

   At least I have livened up the forum for a while !!............FWIW..................<:)

 

Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold

 

 

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From: "Rogers, Bob J." <BRogers@FDIC.gov>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Tue, August 17, 2010 5:20:49 PM
Subject: [FlyRotary] Re: Turbo Questions

Yes, I used the Jet-Hot 2000 coating, shown at this link. http://www.jet-hot.com/headercoatings.html  I think that it is very effective to reduce heat in the engine compartment.

 

It is only applied at the Oklahoma City facility.

 

Bob

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From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Kelly Troyer
Sent: Tuesday, August 17, 2010 3:02 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Turbo Questions

 

Bob,

  Did you have your turbine housing and exhaust pipe coated with heat resistant

coating and if so what and where ??.............

 

Thanks,
 

Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold

 

 

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From: " Rogers, Bob J. " <BRogers@FDIC.gov>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Mon, August 16, 2010 10:57:22 AM
Subject: [FlyRotary] Re: Turbo Questions

Kelly,

 

There is one pretty good picture of the turbo installation (before radiator baffling) on our EAA Chapter 1246 website at:  http://www.eaa1246.org/projectsnplanesdisplay.asp?id=10&pic=190. ; Because the oil drains from the turbo into a sump that is lower than the oil pan, I must use an electric pump to transfer the oil back into the engine oil pan.  Attached is a view from the front, which shows the hoses and tubing from the turbo compressor to the intercooler and back to the intake manifold. 

 

Bob

 

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From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Kelly Troyer
Sent: Monday, August 16, 2010 10:02 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Turbo Questions

 

Bob,

   I am waiting on a clarification  from "Turbonetics" as to what size turbine wheel

would turn the least rpm as altitude increases.............I know the  turbine housing

a/r ratio is a big factor effecting turbine rpm as we climb but it is not clear to me

how the turbine wheel diameter and trim factor in.............Air density lessens with

altitude but I am not smart enough to know if the larger or smaller turbine wheel

will have the highest rpm because of this factor as we climb ??.........

 

  Perhaps I am being anal about this but and you are probably correct that that the

effect of a 3mm diameter difference between the two turbine wheels is slight and

probably inconsequential...........If any of our multi-talented group members would

like to shine some light on this please jump in here !!..........

 

  On another note do you happen to have any photos of your 13B/turbo installation

during construction that you would care to share with the group ??..........You have

a beautiful (to Rotorheads) and well thought out installation which from your report

is working very well and I am sure others of the group would like to plagiarize.....<:)

 

Best Regards, 

   

Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold

 

 

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From: " Rogers, Bob J. " <BRogers@FDIC.gov>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Fri, August 13, 2010 11:49:06 AM
Subject: [FlyRotary] Re: Turbo Questions

Kelly,

 

I do not know which wheel is in my turbo.  I expect the larger wheel (68 mm) to turn a little more slowly, since it has a larger surface area to absorb the exhaust, but it should not make much difference.  Either one should be OK.  The Turbonetics people can probably explain the performance differences between the two wheel sizes.

 

Bob

 

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From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Kelly Troyer
Sent: Thursday, August 12, 2010 3:44 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Turbo Questions

 

Bob,

  Thanks much for the info.................Just one more question..............Info from "Turbonetics"
says the 1.15 a/r turbine housing is limited to the F1-65 mm or F1-68 mm turbine wheel.......

  Do you have info as to what turbine wheel was installed in your 60-1 turbo ??..............

 

Thanks Again,

 

Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold

 

 

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From: " Rogers, Bob J. " <BRogers@FDIC.gov>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, August 12, 2010 1:39:26 PM
Subject: [FlyRotary] Re: Turbo Questions

Kelly,

 

I limit my takeoff power to no more than 42 “ of manifold pressure (“MP”), usually just 40” .  At altitudes of 5,000 feet and above, I generally run no more than about 36 “ MP (15 GPH) and 180 knots.  Engine RPM is about 5,800.  The turbo is capable of considerably more boost than this, but I have to watch engine water and oil temps at higher power settings.  I do not want to run more than 200 degrees on oil or water and prefer 180 degrees.  I can maintain these temps (even on hot days) with cowl flap settings from closed to full open as long as I keep the power settings at or below those described above.  One day, I climbed to 11,000 feet and my GPS groundspeed (with a slight tailwind) was 213 knots.  MP was 36”, RPM 6,000.  I have a 68” diameter x 84 pitch Prince P-tip fixed pitch prop coupled to the RWS 2.17/1 reduction unit.

 

Bob