X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from exchange.carey.wa.edu.au ([118.82.44.212] verified) by logan.com (CommuniGate Pro SMTP 5.4c3j) with ESMTPS id 4960519 for flyrotary@lancaironline.net; Thu, 28 Apr 2011 10:13:16 -0400 Received-SPF: none receiver=logan.com; client-ip=118.82.44.212; envelope-from=stevei@carey.asn.au Received: from exchange.carey.local ([10.10.0.5]) by exchange.carey.local ([10.10.0.5]) with mapi; Thu, 28 Apr 2011 22:12:01 +0800 From: To: Date: Thu, 28 Apr 2011 22:12:33 +0800 Subject: Re: [FlyRotary] Re: Cooling Inlets Thread-Topic: [FlyRotary] Re: Cooling Inlets Thread-Index: AcwFrj4xzmxwWrJPR+27o8DE48UfOA== Message-ID: <8CDEAC31-D311-4D03-8FEF-4FD2A91F5568@carey.asn.au> References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: multipart/alternative; boundary="_000_8CDEAC31D3114D038FEF4FD2A91F5568careyasnau_" MIME-Version: 1.0 --_000_8CDEAC31D3114D038FEF4FD2A91F5568careyasnau_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable 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 pipe= s are still there but they have properly shaped bellmouths on them. The s= hape 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 cop= ied 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 co= oler. 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. The significant change with the new inlet shape is that they appear to capt= ure 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 o= n a 94 deg. F day and I could not get the oil temp above 200 degrees in a m= ax power climb. They may have gone higher if the air temperature remaine= d constant but at 3500 fpm the rapidly decreasing OAT kept the temps well u= nder 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 th= e sender immediately and then delete/destroy the e-mail and any printed cop= ies. All liability for viruses is excluded to the fullest extent of the law= . --_000_8CDEAC31D3114D038FEF4FD2A91F5568careyasnau_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable 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 att= ached)  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 wer= e 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 co= oler and 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. 

The significant change with the new inlet shape is that they appear to capt= ure 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.  A= t 130 MPH the pressure would almost double when the throttle was advanced t= o WOT.   That did not happen nearly as much with the simple pipes.  

These inlets ROCK!

Tracy Crook
<inlets_front.jpg><RtInlet.jpg>--
Homepage:  http://www.flyrotary.= com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/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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