X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-yi0-f52.google.com ([209.85.218.52] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTPS id 5092525 for flyrotary@lancaironline.net; Mon, 15 Aug 2011 08:53:37 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.218.52; envelope-from=rwstracy@gmail.com Received: by yie13 with SMTP id 13so7991918yie.25 for ; Mon, 15 Aug 2011 05:53:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=subject:references:from:content-type:x-mailer:in-reply-to :message-id:date:to:content-transfer-encoding:mime-version; bh=jXx6sG0VZ/bKXJj4oRyT9OskYV1XroDSpQlMP/y7hz8=; b=C2JMYWQxzdg/bkdA1wVW1nRzm8UuCYwEY5+lklwoyUQXUHcWLZuEMq4wjG0xnS8Vgx 4YvXCHlk2Pd7dG+KozB6QlKIkOg1RAmoTwl47zKYwYWtrsQ0IoY0+kiynD/nMnx1ctCC G2db9Obe0023nyspVrDFRRlVTgNsx/108LYVI= Received: by 10.236.115.73 with SMTP id d49mr11958159yhh.245.1313412782199; Mon, 15 Aug 2011 05:53:02 -0700 (PDT) Return-Path: Received: from [10.0.1.2] (99-197-145-127.cust.wildblue.net [99.197.145.127]) by mx.google.com with ESMTPS id q25sm4875530yhm.76.2011.08.15.05.52.50 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 15 Aug 2011 05:53:00 -0700 (PDT) Subject: Re: [FlyRotary] Re: 20B RV-8 altitude test results References: From: Tracy Content-Type: multipart/alternative; boundary=Apple-Mail-34-98125942 X-Mailer: iPad Mail (8F191) In-Reply-To: Message-Id: <643C8457-5B44-4B29-81E7-99F62F2CC9BA@gmail.com> Date: Mon, 15 Aug 2011 08:52:41 -0400 To: Rotary motors in aircraft Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (iPad Mail 8F191) --Apple-Mail-34-98125942 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Mark wrote: =20 Maybe I need to start flying higher. How do they compare to your lower alti= tude numbers? =20 The fuel burn is MUCH higher at lower altitude. I haven't bothered to reco= rd accurate numbers there on the RV-8 yet but I do have the numbers on the -= 4. Just coincidently, the top speed of the -4 at sea level is almost exac= tly the same as my 10 GPH test of the RV-8 at 14000 ft. (224 mph). That w= as the IAS I flew the -4 at during the SUN 100 in 2004. It was burning exac= tly twice the fuel at 20 GPH. Altitude is the best investment you can make for fuel economy on a long trip= . =20 Tracy Sent from my iPad On Aug 14, 2011, at 6:17 PM, Mark Steitle wrote: > Tracy,=20 >=20 > Did you secretly swap out the 20B for a Renesis without telling anyone? T= hose numbers look fantastic. They look like what I would expect to see from= a 2-rotor. Maybe I need to start flying higher. How do they compare to yo= ur lower altitude numbers? =20 >=20 > Mark >=20 > P.S. Can you provide the missing info for my spreadsheet? Prop, mods, si= gnificant events >=20 >=20 > On Sun, Aug 14, 2011 at 4:12 PM, Tracy wrote: > Got the coils changed out from RX-8s to a mixture of LS2 and LS1 coils and= installed in an improved air box. Coils much cooler now. >=20 > Ran with auto pilot on to hold altitude steady during tests so I think the= y are pretty accurate. I was mainly interested in fuel economy and speed at= various fuel flows. All these results were at 14,000 feet. I'll do some a= t 18,000 where the results should look even better next time. I forgot to d= ress warmer because the temp on ground was 94 F. OAT during test was 39F. = Speeds are TAS. =20 >=20 > 6.0 GPH 169 mph. 28.1 mpg > 7.0 GPH. 180 mph. 25.7 mpg > 8.0. GPH. 200 mph. 25 mpg > 10.0 GPH. 224 mph. 22.4 mpg >=20 > The manifold pressures sounded a bit unrealistic during test but 2 differe= nt instruments agreed so I think they are right. The only one I wrote down= was at 7 GPH where it was at 13.9" Hg and rpm was 5174. The sweet spot se= ems to be very close to 8.0 GPH. I think that is where the rpm gets into t= he area where the fuel charge is stratified by the centrifugal force at arou= nd 5400 rpm and the mixture can be aggressively leaned. >=20 > The goal is to get 30 mpg at 200 MPH at 18000 ft. If I can get there I ca= n fly non stop from FL to CO with only a small aux fuel tank. >=20 > Tracy > Sent from my iPad >=20 > On Aug 14, 2011, at 1:41 PM, Charlie England wro= te: >=20 >>=20 >>> Who's flying one (P-ported *Renesis*), & does it meet *both* criteria? >> Clarification: If I read correctly, the question was about complex intake= vs adding a supercharger & using it to 'normalize' only back to the output o= f a properly done intake. My point is that a manifold like Tracy's is very s= imple to build (much simpler than anything for an aftermarket supercharger),= and the power (and efficiency) is there with much less weight & much higher= reliability. Higher *output* & high altitude benefits are still there, but t= hat wasn't the question. >>=20 >> Obviously, after the P-port is done the intake is simpler (by 2 tubes), b= ut not that many homebuilders have the resources to do the P-port mod, which= makes the manifold look like child's play. >>=20 >> Charlie >>>=20 >>> On 08/14/2011 10:02 AM, Mark Steitle wrote: >>>>=20 >>>> Charlie, =20 >>>>=20 >>>> Maybe you meant "...best power of all side ported rotaries". I'm prett= y sure that a p-ported 13B would easily produce more power than a side port m= otor, assuming they do a good job on the intake and exhaust. The nice thing= about a p-port motor is the intake is simpler and easier to build than a si= de port intake. =20 >>>>=20 >>>> Mark S. >>>>=20 >>>> On Sun, Aug 14, 2011 at 8:34 AM, Charlie England wrote: >>>> On the subject of Renesis intake complexity, take a look at Tracy's int= ake (pic from his web site). >>>>> >>>>=20 >>>>> http://www.rotaryaviation.com/renesis_engine.htm >>>> Can't get much simpler, & as far as I know, he has the best power numbe= rs and the best efficiency numbers of anyone flying. His intake tubes are no= w longer than in this shot, but as you can see from the pic, adjusting tube l= ength (retuning) is pretty straightforward.=20 >>>>=20 >>>> Charlie >>>>=20 >>>>=20 >>>>=20 >>>>=20 >>>> On 08/14/2011 06:36 AM, Ed Anderson wrote: >>>>>=20 >>>>> Sam, As you find in this "hobby" there are always trade offs. First,= technically there is no reason you could not do what you propose - however,= you will add weight and complexity. A poor intake affects both N/A and for= ced induction - its just with forced induction you are= paying in a different way to overcome any defficiencies in your intake.=20 >>>>> =20 >>>>> If going that route, I personally would prefer the centrifugal type b= elt/gear driven blower over the roots type which has historically had the po= orest efficiency. On the other hand, if you are not going to "boost" above a= mbient pressure - then I think I would concentrate on getting a good N/A int= ake. >>>>> =20 >>>>> Good luck on your project whichever decision/approach you take. Super= and Turbo chargers have both been used successfully. >>>>> =20 >>>>> just my $0.02\ >>>>> =20 >>>>> Ed >>>>>=20 >>>>> From: Samuel Treffinger >>>>> Sent: Sunday, August 14, 2011 1:01 AM >>>>> To: Rotary motors in aircraft >>>>> Subject: [FlyRotary] Renesis Question >>>>>=20 >>>>> I think my brain has had a meltdown: I am thinking about "supernormali= zing" the Renesis engine. Is this even possible. The idea is to use a by-pas= sable positive displacement type blower (roots type...probably an eaton m90)= fed to an intercooler that then sends air to the engine. If my thinking is c= orrect, and it probably isn't, this would eliminate the complex N/A intake, w= hile not over-boosting the Renesis engine. Also, the supercharger being a po= sitive displacement blower would in theory produce more bo= ost than is needed by the engine at all rpm levels, eliminating the "peeky" t= orque of boosted engines. The excess (above standard intake) pressure would b= e controlled via an automatic or manual waste-gate. Please shoot my idea dow= n if it is insane, but i would like some constructive criticism if it is ava= ilable. >>>>>=20 >>>>> Sam >>>>=20 >>>>=20 >>>=20 >>=20 >=20 --Apple-Mail-34-98125942 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8
Mark wrote:    
M= aybe I need to start flying higher.  How do they compare to your lower a= ltitude numbers?  


The fuel burn is MUCH higher at lower altitude.   I haven't bothered t= o record accurate numbers there on the RV-8 yet but I do have the numbers on= the -4.   Just coincidently, the top speed of the -4 at sea level &nbs= p;is almost exactly the same as my 10 GPH test of the RV-8 at 14000 ft. &nbs= p;(224 mph).   That was the IAS I flew the -4 at during the SUN 100 in 2= 004.  It was burning exactly twice the fuel at 20 GPH.

Altitude is the best investment you can make for fuel economy on a l= ong trip.  

Tracy

Sent from my iPad

On Aug 14, 2011, at 6:17 PM, Mark Steitle <msteitle@gmail.com> wrote:

Tracy, 

Did you secr= etly swap out the 20B for a Renesis without telling anyone?  Those numb= ers look fantastic.  They look like what I would expect to see from a 2= -rotor.  Maybe I need to start flying higher.  How do they compare= to your lower altitude numbers?  

Mark

P.S.  Can you provide= the missing info for my spreadsheet?  Prop, mods, significant events


On Sun, Aug 14, 2011 a= t 4:12 PM, Tracy <rwstracy@gmail.com>= wrote:
Got the coils c= hanged out from RX-8s to a mixture of LS2 and LS1 coils and installed in an i= mproved air box.   Coils much cooler now.

Ran with auto pilot on to hold altitude steady during te= sts so I think they are pretty accurate.  I was mainly interested in fu= el economy and speed at various fuel flows.   All these results were at= 14,000 feet.  I'll do some at 18,000 where the results should look eve= n better next time.  I forgot to dress warmer because the temp on groun= d was 94 F.   OAT during test was 39F.  Speeds are TAS.  

6.0 GPH   169 mph.  28.1 mpg
7.0 GPH= .   180 mph.  25.7 mpg
8.0. GPH.   200 mph. 25 mpg<= /div>
10.0 GPH.  224 mph. 22.4 mpg

The man= ifold pressures sounded a bit unrealistic during test but 2 different instru= ments agreed so I think they are right.   The only one I wrote down was= at 7 GPH where it was at 13.9" Hg and rpm was 5174.   The sweet spot s= eems to be very close to 8.0 GPH.   I think that is where the rpm gets i= nto the area where the fuel charge is stratified by the centrifugal force at= around 5400 rpm and the mixture can be aggressively leaned.

The goal is to get 30 mpg at 200 MPH at 18000 ft.  = If I can get there I can fly non stop from FL to CO with only a small aux fu= el tank.

Tracy
Sent from my iPad

On Au= g 14, 2011, at 1:41 PM, Charlie England <ceen= gland@bellsouth.net> wrote:


=20 Who's flying one (P-ported *Renesis*), & does it meet *both* criteria?
Clarification: If I read correctly, the question was about complex intake vs adding a supercharger & using it to 'normalize' only back to the output of a properly done intake. My point is that a manifold like Tracy's is very simple to build (much simpler than anything for an aftermarket supercharger), and the power (and efficiency) is there with much less weight & much higher reliability. Higher *output* & high altitude benefits are still there, but that wasn't the question.

Obviously, after the P-port is done the intake is simpler (by 2 tubes), but not that many homebuilders have the resources to do the P-port mod, which makes the manifold look like child's play.

Charlie

On 08/14/2011 10:02 AM, Mark Steitle wrote:
Charlie,  

Maybe you meant "...best power of all side ported rotaries".  I'm pretty sure that a p-ported 13B would easily produce more power than a side port motor, assuming they do a good job on the intake and exhaust.  The nice thing about a p-port motor is the intake is simpler and easier to build than a side port intake.  

Mark S.

On Sun, Aug 14, 2011 at 8:34 AM, Charlie England <ceengland= @bellsouth.net> wrote:
On the subject of Renesis intake complexity, take a look at Tracy's intake (pic from his web site).
<mime-attachment.jpg>
http://www.rotaryaviation.com/renesis_e= ngine.htm
Can't get much simpler, & as far as I know, he has the best power numbers and the best efficiency numbers of anyone flying. His intake tubes are now longer than in this shot, but as you can see from the pic, adjusting tube length (retuning) is pretty straightforward.

Charlie




On 08/14/2011 06:36 AM, Ed Anderson wrote:
Sam, As you find in this "hobby" there  are always trade offs.  First= , technically there is no reason you could not do what you propose - however, you will add weight and complexity.  A poor intake affects both N/A and forced induction - its just with forced induction you are paying in a different way to overcome any defficiencies in your intake. 
 
 If going that route, I personally would prefer the centrifugal type belt/gear driven blower over the roots type which has historically had the poorest efficiency.  On the other hand, if you are not going to "boost" above ambient pressure - then I think I would concentrate on getting a good N/A intake.
=
 
Good luck on your project whichever decision/approach you take.  Super and Turbo chargers have both been used successfully.
 
just my $0.02\
 
Ed

Sent: Sunday, August 14, 2011 1:01 AM
Subject: [FlyRotary] Renesis Question

I think my brain has had a meltdown: I am thinking about "supernormalizing" the Renesis engine. Is this even possible. The idea is to use a by-passable positive displacement type blower (roots type...probably an eaton m90) fed to an intercooler that then sends air to the engine. If my thinking is correct, and it probably isn't, this would eliminate the complex N/A intake, while not over-boosting the Renesis engine. Also, the supercharger being a positive displacement blower would in theory produce more boost than is needed by the engine at all rpm levels, eliminating the "peeky" torque of boosted engines. The excess (above standard intake) pressure would be controlled via an automatic or manual waste-gate. Please shoot my idea down if it is insane, but i would like some constructive criticism if it is available.

Sam




=20

= --Apple-Mail-34-98125942--