X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from QMTA12.emeryville.ca.mail.comcast.net ([76.96.27.227] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3750193 for flyrotary@lancaironline.net; Wed, 08 Jul 2009 21:27:04 -0400 Received-SPF: pass receiver=logan.com; client-ip=76.96.27.227; envelope-from=wschertz@comcast.net Received: from OMTA19.emeryville.ca.mail.comcast.net ([76.96.30.76]) by QMTA12.emeryville.ca.mail.comcast.net with comcast id Daqd1c00B1eYJf8ACdSUpX; Thu, 09 Jul 2009 01:26:28 +0000 Received: from WschertzPC ([71.57.77.95]) by OMTA19.emeryville.ca.mail.comcast.net with comcast id DdSS1c00923NHuF01dSTzv; Thu, 09 Jul 2009 01:26:28 +0000 Message-ID: From: "Bill Schertz" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: INJECTION OIL IN FUEL Date: Wed, 8 Jul 2009 20:26:25 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_01EF_01CA000A.5D7322A0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6001.18000 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6001.18049 This is a multi-part message in MIME format. ------=_NextPart_000_01EF_01CA000A.5D7322A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Don't forget to add the speed of the airplane to your numbers. Bill Schertz KIS Cruiser #4045 N343BS Phase I testing ----- Original Message -----=20 From: Berniehb7448@wmconnect.com=20 To: Rotary motors in aircraft=20 Sent: Tuesday, July 07, 2009 8:45 PM Subject: [FlyRotary] Re: INJECTION OIL IN FUEL This is what I figured out as my "formula":=20 Max Prop RPM & Speed of Sound=20 1 Mile =3D 5,280 Feet=20 Speed of Sound =3D 768 mph (I think this is at sea level barometric = pressure, I haven't figured out what happens with altitude.)=20 pi =3D 3.1429=20 6 FT (72") D (Diameter) Prop=20 CIRCUMFERENCE =3D pi X D =3D 3.1429 X 6 ft =3D 18.857 ft = Circumference=20 1 RPM =3D 18.857 ft/Minute at prop tip=20 With 2:1 PSRU Reduction, calculate by prop RPM and Circumference:=20 Prop RPM 3,000 (Engine RPM 6,000) =3D 56,571 ft/Minute =3D 10.714 = miles/minute =3D 642.84 MPH=20 (768 MPH - 642.84 MPH =3D 125.16 MPH under Speed of Sound)=20 Prop RPM 3,500 (Engine RPM 7,000) =3D 66,000 ft/Minute =3D 12.5 = miles/minute =3D 750 MPH=20 (768 MPH - 750 MPH =3D 18 MPH under Speed of Sound)=20 = =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=20 I paid enough attention in my math classes to think I've got it right. = Here's one for you: Does a cogbelt PSRU's powerlimit increase with a = wider belt? Like, for example, if a two incher can handle 150 HP, then = you might need a four inch belt to handle 300 HP. Something like that?=20 Here's another: One maker put an engine RPM limit on the PSRU, and I'm = thinking it has to do with the capability of the bearing at the input = end. Maybe because these bearings are sealed - they don't run in an oil = bath.=20 Thank you, Bernie. ------=_NextPart_000_01EF_01CA000A.5D7322A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Don't forget to add the speed of the = airplane to=20 your numbers.
Bill Schertz
KIS Cruiser #4045
N343BS
Phase I = testing
----- Original Message -----
From:=20 Berniehb7448@wmconnect.com=
Sent: Tuesday, July 07, 2009 = 8:45=20 PM
Subject: [FlyRotary] Re: = INJECTION OIL IN=20 FUEL

This is=20 what I figured out as my "formula":

Max Prop RPM & Speed = of Sound=20

1 Mile =3D 5,280 Feet

Speed of Sound =3D  768 mph = (I think=20 this is at sea level barometric pressure, I haven't figured out what = happens=20 with altitude.)

pi =3D 3.1429

6 FT (72") D (Diameter) = Prop=20

CIRCUMFERENCE =3D  pi X D =3D   3.1429  X =  6 ft=20  =3D 18.857 ft Circumference

1 RPM =3D 18.857 ft/Minute = at prop tip=20

With 2:1 PSRU Reduction, calculate by prop RPM and = Circumference:=20
Prop RPM 3,000 (Engine RPM 6,000) =3D  56,571 ft/Minute =3D = 10.714=20 miles/minute =3D 642.84 MPH
(768 MPH - 642.84 MPH  =3D 125.16 = MPH under=20 Speed of Sound)
Prop RPM 3,500 (Engine RPM 7,000) =3D  66,000 = ft/Minute=20 =3D 12.5 miles/minute =3D 750 MPH
(768 MPH - 750 MPH  =3D 18 = MPH under=20 Speed of Sound) =
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
I=20 paid enough attention in my math classes to think I've got it right.=20

Here's one for you: Does a cogbelt PSRU's powerlimit increase = with a=20 wider belt? Like, for example, if a two incher can handle 150 HP, then = you=20 might need a four inch belt to handle 300 HP. Something like that? =
Here's=20 another: One maker put an engine RPM limit on the PSRU, and I'm = thinking it=20 has to do with the capability of the bearing at the input end. Maybe = because=20 these bearings are sealed - they don't run in an oil bath.
Thank = you,=20 Bernie. ------=_NextPart_000_01EF_01CA000A.5D7322A0--