X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 30 [X] Return-Path: Received: from mail01.syd.optusnet.com.au ([211.29.132.182] verified) by logan.com (CommuniGate Pro SMTP 5.1.9) with ESMTPS id 2061958 for flyrotary@lancaironline.net; Tue, 22 May 2007 17:51:17 -0400 Received-SPF: none receiver=logan.com; client-ip=211.29.132.182; envelope-from=lendich@optusnet.com.au Received: from george (d211-31-197-148.dsl.nsw.optusnet.com.au [211.31.197.148]) by mail01.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id l4MLoV65007349 for ; Wed, 23 May 2007 07:50:33 +1000 Message-ID: <005f01c79cbb$3bd2da00$94c51fd3@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Gear box oil temps Date: Wed, 23 May 2007 07:50:36 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_005C_01C79D0F.0C59A3E0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_005C_01C79D0F.0C59A3E0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Al can you mount a separate small rad for the PSRU? George ( down under) Figures I found on the web indicates 3% is a fairly standard figure = used for a planetary gearbox efficiency. So 3% of 160 HP =3D 4.8 HP which is mostly converted to heat. Tf =3D 180F + (203/((7.3 *.5) *0.4) =3D 180F + 69F =3D 249F So using this example and assuming I haven't screwed up, I would = expect the oil temps coming out of the gear box to be around 249F. =20 Ed; I really appreciate when you take the time and effort to do the math = that I'm to lazy to do. I think at the time I noted the re-drive temp out it was 243F, shortly = after leveling off from a climb, and the oil temp (after cooler, into = drive) was still about 210F. I'm gonna guess the power at that point was = about 140 hp. So it seems that the efficiency and/or the flow rate is a = bit higher. In any case; I'll proceed on with worrying about that = outlet temp. Thanks. BTW; I think that monitoring the redrive outlet is important. It can = give you a heads up on problems with the redrive. It is nice to be able = to set a limit in the EM to alert you of a potential problem. Al=20 ------=_NextPart_000_005C_01C79D0F.0C59A3E0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Al can you mount a separate small = rad for the=20 PSRU?

George ( down under)

Figures I found on the = web=20 indicates 3% is a fairly standard figure used for a planetary gearbox=20 efficiency.

So 3% of 160 HP =3D 4.8 = HP =20 which is mostly converted to heat.

Tf =3D 180F + (203/((7.3 = *.5) *0.4) =3D 180F = + 69F =3D=20 249F

So using this example = and assuming=20 I haven't screwed up, I would expect the oil temps coming out of = the=20 gear box to be around 249F.

Ed;

I really = appreciate=20 when you take the time and effort to do the math that I=92m to lazy to = do.

I think = at the time=20 I noted the re-drive temp out it was 243F, shortly after leveling off = from a=20 climb, and the oil temp (after cooler, into drive) was still about = 210F. I=92m=20 gonna guess the power at that point was about 140 hp. So it = seems that=20 the efficiency and/or the flow rate is a bit higher. In any = case; I=92ll=20 proceed on with worrying about that outlet temp.

Thanks.

BTW; I = think that=20 monitoring the redrive outlet is important. It can give you a = heads up=20 on problems with the redrive. It is nice to be able to set a = limit in=20 the EM to alert you of a potential problem.

Al=20

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