X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-ww0-f50.google.com ([74.125.82.50] verified) by logan.com (CommuniGate Pro SMTP 5.4c3j) with ESMTPS id 4960692 for flyrotary@lancaironline.net; Thu, 28 Apr 2011 12:25:48 -0400 Received-SPF: pass receiver=logan.com; client-ip=74.125.82.50; envelope-from=rwstracy@gmail.com Received: by wwc33 with SMTP id 33so2589099wwc.7 for ; Thu, 28 Apr 2011 09:25:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; bh=ZF6INiWXETFYSsaiTWQoT8OYq7eoVYbTw1wi6RJ8dCk=; b=g5iivFtvJQI6vqy2kfdd+roSOb+AFjjOUhb+43X+mRKf49eN1+0nbWuXGSDAACrJwJ NQP6QxevfF+aEFZVeRT41aqUdI78Alqn61XG0FmyJJQNRN0WxE9Os3Q3EBPSd0ZhC5D4 hfZr8zvyKZjK4578MQQOnIGLzr+V349YBOjIQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=dEY4l75QUPV4GIwkmNJhggWC95TBeChun0hoUa7MsAKFz5sR//PtF4KVUvBmX37gse ApJ+cAIfTCgO6T8kKh9qeCH+tMPiU659/Sm5MR6w757kPa416H3M84T/Kf+P4CgiKrEM BfEUV5p2ZwxXDHfXp7SnHY7wywxH36vp61ImM= MIME-Version: 1.0 Received: by 10.216.79.11 with SMTP id h11mr3529932wee.77.1304007911903; Thu, 28 Apr 2011 09:25:11 -0700 (PDT) Received: by 10.216.190.132 with HTTP; Thu, 28 Apr 2011 09:25:11 -0700 (PDT) In-Reply-To: References: Date: Thu, 28 Apr 2011 12:25:11 -0400 Message-ID: Subject: Re: [FlyRotary] Re: Cooling Inlets From: Tracy To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=000e0ce0d1205f902104a1fd0029 --000e0ce0d1205f902104a1fd0029 Content-Type: text/plain; charset=ISO-8859-1 Sorry, my bad. Typo error. Try CR 3405 Tracy On Thu, Apr 28, 2011 at 10:12 AM, wrote: > Thanks very much for the feedback on your cooling design Tracy. > I'm having no joy googling NASA_CR3485. > What am I doing wrong? > > Steve Izett > Perth WA > > On 28/04/2011, at 9:07 PM, Tracy wrote: > > Finally got around to finishing my cooling inlets. (pictures attached) Up > until now they were simply round pipes sticking out of the cowl. The pipes > are still there but they have properly shaped bellmouths on them. The > shape and contours were derived from a NASA contractor report (NASA_CR3485) > that you can find via Google. Lots of math & formulas in it but I just > copied the best performing inlet picture of the contour. Apparently there > is an optimum radius for the inner and outer lip of the inlet. There was > no change to the inlet diameters of 5.25" on water cooler and 4.75" on oil > cooler. > > The simple pipes performed adequately in level flight at moderate cruise > settings even on hot days but oil temps would quickly hit redline at high > power level flight and in climb. > > The significant change with the new inlet shape is that they appear to > capture off-axis air flow (like in climb and swirling flow induced by prop > at high power) MUCH better than the simple pipes. First flight test was > on a 94 deg. F day and I could not get the oil temp above 200 degrees in a > max power climb. They may have gone higher if the air temperature > remained constant but at 3500 fpm the rapidly decreasing OAT kept the temps > well under redline (210 deg F). > > I have an air pressure instrument reading the pressure in front of the oil > cooler and was amazed at the pressure recovered from the prop wash. At 130 > MPH the pressure would almost double when the throttle was advanced to WOT. > That did not happen nearly as much with the simple pipes. > > These inlets ROCK! > > Tracy Crook > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > > ------------------------------ > The contents of this email are confidential and intended only for the named > recipients of this e-mail. If you have received this e-mail in error, you > are hereby notified that any use, reproduction, disclosure or distribution > or the information contained in this e-mail is prohibited. Please notify the > sender immediately and then delete/destroy the e-mail and any printed > copies. All liability for viruses is excluded to the fullest extent of the > law. > --000e0ce0d1205f902104a1fd0029 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sorry, my bad.=A0 Typo error.=A0 Try CR 3405

Tracy

On Thu, Apr 28, 2011 at 10:12 AM, <<= a href=3D"mailto:stevei@carey.asn.au">stevei@carey.asn.au> wr= ote:
Thanks very much for the feedback on your cooling design Tracy.
I'm having no joy googling NASA_CR3485.
What am I doing wrong?

Steve Izett
Perth WA

On 28/04/2011, at 9:07 PM, Tracy wrote:

Finally got around to finishing my cooli= ng inlets. (pictures attached)=A0 Up until now they were simply round pipes= sticking out of the cowl.=A0=A0 The pipes are still there but they have properly shaped bellmouths on them.=A0=A0 The shape and contours were deri= ved from a NASA contractor report (NASA_CR3485) that you can find via Googl= e.=A0 Lots of math & formulas in it but I just copied the best performi= ng inlet picture of the contour.=A0=A0 Apparently there is an optimum radius for the inner and outer lip of the inlet.=A0=A0= There was no change to the inlet diameters of 5.25" on water cooler a= nd 4.75" on oil cooler.

The simple pipes performed adequately in level flight at moderate cruise se= ttings even on hot days but oil temps would quickly hit redline at high pow= er level flight and in climb.=A0

The significant change with the new inlet shape is that they appear to capt= ure off-axis air flow=A0 (like in climb and swirling flow=A0 induced by pro= p at high power)=A0 MUCH better than the simple pipes. =A0=A0 First flight = test was on a 94 deg. F day and I could not get the oil temp above 200 degrees in a max power climb. =A0=A0 They may h= ave gone higher if the air temperature remained constant but at 3500 fpm th= e rapidly decreasing OAT kept the temps well under redline (210 deg F).

I have an air pressure instrument reading the pressure in front of the oil = cooler and was amazed at the pressure recovered from the prop wash.=A0 At 1= 30 MPH the pressure would almost double when the throttle was advanced to W= OT. =A0 That did not happen nearly as much with the simple pipes.=A0=A0

These inlets ROCK!

Tracy Crook
<inlets_front.jpg><RtIn= let.jpg>--
Homepage: =A0http:/= /www.flyrotary.com/
Archive and UnSub: =A0=A0http://mail.lancaironline.net:81/lis= ts/flyrotary/List.html


The contents of this email a= re confidential and intended only for the named recipients of this e-mail. = If you have received this e-mail in error, you are hereby notified that any= use, reproduction, disclosure or distribution or the information contained in this e-mail is prohibited. Please notify t= he sender immediately and then delete/destroy the e-mail and any printed co= pies. All liability for viruses is excluded to the fullest extent of the la= w.

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