Return-Path: Sender: (Marvin Kaye) To: flyrotary Date: Fri, 10 Oct 2003 23:54:28 -0400 Message-ID: X-Original-Return-Path: Received: from [24.93.67.82] (HELO ms-smtp-01-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP id 2632235 for flyrotary@lancaironline.net; Fri, 10 Oct 2003 22:06:46 -0400 Received: from o7y6b5 (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-01-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id h9B26iLe010022 for ; Fri, 10 Oct 2003 22:06:45 -0400 (EDT) X-Original-Message-ID: <000801c38f9b$afd9df60$1702a8c0@WorkGroup> From: "Ed Anderson" X-Original-To: "Rotary motors in aircraft" Subject: New Turbo Rotary Spreadsheet Calculator X-Original-Date: Fri, 10 Oct 2003 22:02:12 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0005_01C38F7A.288CBD00" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 This is a multi-part message in MIME format. ------=_NextPart_000_0005_01C38F7A.288CBD00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Due to overwhelming popular demand.... Ok, Ok, at least one person = requested it. I have now created a spreadsheet where you can run NA or = with a turbo charger. The HP, fuel burn and BTUs should work out pretty = good and even the cooling section. The tubo model does take into = account the less dense air after compression since that affects power. = But there is NO turbo modeling done. I used 65% efficiency for the = compressor efficiency which may be a bit on the low side, but is = conservative. The cooling section now permits you to specify a different radiator size = than the Gm cores. However, the oil cooler is still an RX-7 oil cooler, = but you can select more than one. Again this simple cooling model is = based on airflow caused by airspeed as constrained by the surface are of = the radiators you specify. It does not taken into consideration = lessening delta T due to radiator thickenss or the decreased pressure = across the radiator either. But, it gave me close to the actual results = I see when I fly - inadequate cooling during take off and intial climb = at high power settings so temps climb, but once I hit around 120 MPH = and/or pull back on power the higher airspeed and lesser power results = in adequate cooling during the cruise climb and more than adequate = during cruise at alititude. yes, I lower the density of the mass air = flow at altitude to try to keep it fairly realistic. But, thats about = it. I will remind everyone that this is not a simulation and while I have = taken a great deal of care into ensuring that the math model for the = engine section is as accurate as I can make it, its only a model and not = a simulation. That means you CAN input 20 psi boost at 1000 rpm and it = will give you the HP that would create although in real life the exhaust = output at 1000 rpm would probably never come close to giving you 20 psi = boost. Soooo, its up to you to input realistic combinations. You know - = the garbage in and garbage out thing. =20 Also since there is not a simulated load on the engine, it will given = you what ever rpm you want (don't you wish real life were this easy) - = however, whether a real engine with a real load and real induction and = exhaust system can achieve that rpm is another question. If anyone has = a simple math model that would provide a load figure based on pitch, = diameter, number of blades that would provide the HP/torque required for = two modes. Say Acceleration (take off) and cruise (steady state) I will = see if I can adapt the program to reflect real world prop loads. Lets = start with a fix pitch prop model {:>). Any Propeller experts on the = list?? To keep Marv from getting on me about consuming too much of the server = disk space, anyone who wants a copy please send me an email off the = list. My email below. Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com ------=_NextPart_000_0005_01C38F7A.288CBD00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Due to overwhelming  popular = demand.... Ok,=20 Ok, at least one person requested it.  I have now created a = spreadsheet=20 where you can run NA or with a turbo charger.  The HP, fuel burn = and BTUs=20 should work out pretty good and even the cooling section.  The tubo = model=20 does take into account the less dense air after compression since that = affects=20 power.  But there is NO turbo modeling done.  I used 65% = efficiency=20 for the compressor efficiency which may be a bit on the low side, but is = conservative.
 
The cooling section now permits you to = specify a=20 different radiator size than the Gm cores.  However, the oil cooler = is=20 still an RX-7 oil cooler, but you can select more than one.  Again = this=20 simple cooling model is based on airflow caused by airspeed as = constrained by=20 the surface are of the radiators you specify.  It does not taken = into=20 consideration lessening delta T due to radiator thickenss or the = decreased=20 pressure across the radiator either.  But, it gave me close to the = actual=20 results I see when I fly - inadequate cooling during take off and intial = climb=20 at high power settings so temps climb, but once I hit around 120 MPH = and/or pull=20 back on power the higher airspeed and lesser power results in adequate = cooling=20 during the cruise climb and more than adequate during cruise at = alititude. =20 yes, I lower the density of the mass air flow at altitude to try to keep = it=20 fairly realistic.  But, thats about it.
 
I will remind everyone that this is not = a=20 simulation and while I have taken a great deal of care into ensuring = that the=20 math model for the engine section is as accurate as I can make it, its = only a=20 model and not a simulation.  That means you CAN input 20 psi boost = at 1000=20 rpm and it will give you the HP that would create although in real life = the=20 exhaust output at 1000 rpm would probably never come close to giving you = 20 psi=20 boost. Soooo, its up to you to input realistic combinations.  You = know -=20 the garbage in and garbage out thing. 
 
Also since there is not a simulated = load on the=20 engine, it will given you what ever rpm you want (don't you wish real = life were=20 this easy) - however, whether a real engine with a real load and real = induction=20 and exhaust system can achieve that rpm is another question.  If = anyone has=20 a simple math model that would provide a load figure based on pitch, = diameter,=20 number of blades that would provide the HP/torque required for two = modes. =20 Say Acceleration (take off) and cruise (steady state) I will see if I = can adapt=20 the program to reflect real world prop loads.  Lets start with a = fix pitch=20 prop model {:>).  Any Propeller experts on the=20 list??
 
To keep Marv from getting on me about = consuming too=20 much of the server disk space, anyone who wants a copy please send me an = email=20 off the list.  My email below.
 
Ed Anderson
RV-6A N494BW Rotary=20 Powered
Matthews, NC
eanderson@carolina.rr.com
------=_NextPart_000_0005_01C38F7A.288CBD00--