X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from omr-d01.mx.aol.com ([205.188.252.208] verified) by logan.com (CommuniGate Pro SMTP 6.0.5) with ESMTPS id 6377261 for flyrotary@lancaironline.net; Wed, 17 Jul 2013 19:35:20 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.252.208; envelope-from=shipchief@aol.com Received: from mtaomg-da04.r1000.mx.aol.com (mtaomg-da04.r1000.mx.aol.com [172.29.51.140]) by omr-d01.mx.aol.com (Outbound Mail Relay) with ESMTP id 4CA37700544F1 for ; Wed, 17 Jul 2013 19:34:46 -0400 (EDT) Received: from core-ddd002b.r1000.mail.aol.com (core-ddd002.r1000.mail.aol.com [172.29.52.197]) by mtaomg-da04.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 0A020E000083 for ; Wed, 17 Jul 2013 19:34:46 -0400 (EDT) References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: Turbo Selection Workbook- Rev1 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: shipchief@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8D0515D5AD9EA26_1758_26E284_webmail-d101.sysops.aol.com" X-Mailer: AOL Webmail 37834-STANDARD Received: from 174.61.189.169 by webmail-d101.sysops.aol.com (205.188.92.224) with HTTP (WebMailUI); Wed, 17 Jul 2013 19:34:45 -0400 Message-Id: <8D0515D5AD064A2-1758-A7B76@webmail-d101.sysops.aol.com> X-Originating-IP: [174.61.189.169] Date: Wed, 17 Jul 2013 19:34:45 -0400 (EDT) x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1374104086; bh=ZOoEFiQTH6nUHQiQPeStunSZIZyZsh78bCgNF38p1nc=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=H9Ubx33gy6/xroywCuRqPN7lkUgDgeMkdL5s8Lm5i192vcu4ZUG9oX+dkADoLQREi ZwOlxxKDwgVb/+qDntVmAchRnuUws82LeDLWqFwFRVr59xgEQFx4MFoAsOkTbYpZAK rvIWGF/7rqhNtELn/7Q1WTHIJ5tHTNANw4VXh6Js= X-AOL-SCOLL-SCORE: 0:2:499726624:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d338c51e72a161ea0 This is a multi-part message in MIME format. ----------MB_8D0515D5AD9EA26_1758_26E284_webmail-d101.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" That would fit in with my recent experience. I have a TO4 turbine with a 60= -1 compressor. The "P trim"exhaust housing A/R is .81. It is being replaced= with an A/R 1.30 exhaust housing, due to the boost coming on too strong at= low RPM. I just re-installed the engine after detonating and rebuilding it= . Yesterday I installed a dual 50" Hg manifold pressure gauge from a Cessna c= enterline twin, hooked to manifold pressure (rear) and Turbo Discharge Pres= sure (front). I can now monitor boost pressure before and after the throttl= e body. The exhaust housing has not been delivered yet. I'm looking at Blow= Off Valves, but customer reviews on several have not been great, and they = are typically about 7 pounds. I'm currently planning to use a 4 PSI radiato= r cap with weld on fill neck on the turbo pipe before the throttle body. I'= ll drill extra holes around the flange to allow more escape flow once the c= ap valve lifts. Old school very light BOV. So far the aircraft weight & balance indicates my 13BT installation is ligh= ter than an O-360 installation, as the weight was light and the Center of G= ravity slightly aft of comparable O-360 powered RV-8s. -----Original Message----- From: CozyGirrrl To: Rotary motors in aircraft Sent: Mon, Jul 15, 2013 8:19 pm Subject: [FlyRotary] Re: Turbo Selection Workbook- Rev1 I read somewhere a few years ago there is not a cert aircraft turbo install= ation with a turbo A/R less than 1, fwiw a data point. =20 Chrissi & Randi www.CozyGirrrl.com ClickBonds 10/$7.50 CG Products, Custom Aircraft Hardware Chairwomen, Sun-N-Fun Engine Workshop =20 In a message dated 7/15/2013 8:55:25 P.M. Central Daylight Time, bhughes@qn= si.net writes: =20 =20 Dave, =20 =20 =20 With the super charger I typically cruise with engine rpm=E2=80=99s betwe= en 4850 and 5400 set with the prop controller. Cruise climb around 5800-6= 200. Throttle Body is wide open and MP controlled with a vernier cable to= the super charger bypass. Applying these settings to the published turbo= compressor maps puts me outside the surge line at low engine rpm and hig= h altitude. Several things could be done to move the pressure ratio lower= . Run higher rpm at altitudes above 15K, use a ram air inlet to eliminate= and boost air pressure at the turbo inlet or use an intercooler with a l= ower pressure drop. I have not been able to find compressor maps that co= mpare different turbine A/R=E2=80=99s for the same compressor components.= My concern would be using a .96 or 1.0 A/R and moving further toward the= surge line. That may not be the case.=20 =20 =20 =20 Bobby =20 =20 =20 =20 =20 =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On B= ehalf Of David Leonard Sent: Monday, July 15, 2013 7:16 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Turbo Selection Workbook- Rev1 =20 =20 =20 =20 Should be no effect. Compressor map is a function of variables independ= ent of what harnessed the energy(ie, the turbine section). That it not t= o say that changing the turbine A/R does not effect overall efficiency an= d a host of other things, just not the compressor map itself.=20 =20 =20 =20 =20 =20 Compressor sections also have an A/R, but changing that would mean that a= whole new compressor map needs to be generated. =20 =20 =20 =20 =20 On Mon, Jul 15, 2013 at 3:33 PM, Bobby J. Hughes wrote: =20 =20 =20 I think I located and corrected two errors. Can anyone explain how the tu= rbine housing A/R affects the compressor map? =20 =20 =20 Bobby =20 =20 =20 =20 =20 =20 =20 =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On B= ehalf Of Bobby J. Hughes Sent: Sunday, July 14, 2013 6:51 PM To: Rotary motors in aircraft Subject: [FlyRotary] Turbo Selection Workbook- Initial Draft =20 =20 =20 I=E2=80=99ve modified a turbo sizing workbook I found on the internet. Th= e modification allow for 8 operational scenarios to account for altitude,= target HP, OAT etc. Each scenario provides a corrected airflow and press= ure ratio needed to select an appropriate turbo. The workbook may contain= errors so I=E2=80=99m sending it out for input. Hopefully Ed or someone = can validate the formulas and those flying turbo aircraft will commit on = real world experience.=20 =20 =20 =20 Bobby Hughes =20 =20 =20 =20 =20 -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.= html =20 =20 =20 =20 =20 --=20 David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.net http://RotaryRoster.net =20 ----------MB_8D0515D5AD9EA26_1758_26E284_webmail-d101.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"
That would fit in with my recent experience. I have a TO4 turbine with= a 60-1 compressor. The "P trim"exhaust housing A/R is .81. It is being rep= laced with an A/R 1.30 exhaust housing, due to the boost coming on too= strong at low RPM. I just re-installed the engine after detonating and&nbs= p;rebuilding it.
Yesterday I installed a dual 50" Hg manifold pressure gauge from = a Cessna centerline twin, hooked to manifold pressure (rear) and Turbo= Discharge Pressure (front). I can now monitor boost pressure before and af= ter the throttle body. The exhaust housing has not been delivered yet. I'm = looking at Blow Off Valves, but customer reviews on several have not been g= reat, and they are typically about 7 pounds. I'm currently planning to= use a 4 PSI radiator cap with weld on fill neck on the turbo pipe before t= he throttle body. I'll drill extra holes around the flange to allow more es= cape flow once the cap valve lifts. Old school very light BOV.
So far the aircraft weight & balance indicates my 13BT installatio= n is lighter than an O-360 installation, as the weight was light and the Ce= nter of Gravity slightly aft of comparable O-360 powered RV-8s.
-----Original Message-----
From: CozyGirrrl <CozyGirrrl@aol.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Mon, Jul 15, 2013 8:19 pm
Subject: [FlyRotary] Re: Turbo Selection Workbook- Rev1

I read somewhere a few years ago there is not a cert aircraft turbo=20 installation with a turbo A/R less than 1, fwiw a data point.
 
Chrissi &=20 Randi

www.CozyGirrrl.com=
ClickBonds=20 10/$7.50
CG Products, Custom Aircraft Hardware
Chairwomen, Sun-N-Fun=20 Engine Workshop
 
In a message dated 7/15/2013 8:55:25 P.M. Central Daylight Time,=20 bhughes@qnsi.net writes:
=20
=20
Dave,
=20
 
=20
With=20 the super charger I typically cruise with engine rpm=E2=80=99s between 48= 50 and 5400=20 set with the prop controller. Cruise climb around 5800-6200. Throttle Bod= y is=20 wide open and MP controlled with a vernier cable to the super charger byp= ass.=20 Applying these settings to the published turbo compressor maps puts me ou= tside=20 the surge line at low engine rpm and high altitude. Several things could = be=20 done to move the pressure ratio lower. Run higher rpm at altitudes above = 15K,=20 use a ram air inlet to eliminate and boost air pressure at the turbo inle= t or=20 use an intercooler with a lower pressure drop.  I have not been able= to=20 find compressor maps that compare different turbine A/R=E2=80=99s for the= same=20 compressor components. My concern would be using a .96 or 1.0 A/R and mov= ing=20 further toward the surge line. That may not be the case.=20
=20
 
=20
Bobby
=20
 
=20
 
=20
 
=20
From: Rotary motors in=20 aircraft [mailto:flyrotar= y@lancaironline.net] On Behalf Of David=20 Leonard
Sent: Monday, July 15, 2013 7:16 PM
To: Rotary=20 motors in aircraft
Subject: [FlyRotary] Re: Turbo Selection=20 Workbook- Rev1
=20
 
=20
=20
Should be no effect.   Compressor map is a fu= nction of=20 variables independent of what harnessed the energy(ie, the turbine sectio= n).=20  That it not to say that changing the turbine A/R does not effect ov= erall=20 efficiency and a host of other things, just not the compressor map=20 itself. 
=20
=20
 
=20
=20
Compressor sections also have an A/R, but changing= that=20 would mean that a whole new compressor map needs to be=20 generated.
=20
=20
 
=20
=20
On Mon, Jul 15, 2013 at 3:33 PM, Bobby J. Hughes &= lt;bh= ughes@qnsi.net> wrote:
=20
=20
=20
I think I located a= nd corrected two errors. Can anyone=20 explain how the turbine housing A/R affects the compressor=20 map?
=20
 
=20
Bobby
=20
 
=20
 
=20
 
=20
=20
=20
From: Rotary motors in=20 aircraft [mailto:flyrotary@lancaironline.net] On = Behalf Of Bobby J.=20 Hughes
Sent: Sunday, July 14, 2013 6:51 PM
To: Rotary=20 motors in aircraft
Subject: [FlyRotary] Turbo Selection Workbook-=20 Initial Draft
=20
 
=20
I=E2=80=99ve modified a=20 turbo sizing workbook I found on the internet. The modification allow for= 8=20 operational scenarios to account for altitude, target HP, OAT etc. Each= =20 scenario provides a corrected airflow and pressure ratio needed to select= an=20 appropriate turbo. The workbook may contain errors so I=E2=80=99m sending= it out for=20 input. Hopefully Ed or someone can validate the formulas and those flying= =20 turbo aircraft will commit on real world experience.
=20
  =20
Bobby Hughes
=20
  =20
 
=20

--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/fl= yrotary/List.html
=20


=20
=20
 
=20
--
David Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRoster.net=20
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