X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from eastrmmtao01.cox.net ([68.230.240.38] verified) by logan.com (CommuniGate Pro SMTP 5.0.8) with ESMTP id 1035258 for flyrotary@lancaironline.net; Wed, 15 Mar 2006 16:33:55 -0500 Received-SPF: none receiver=logan.com; client-ip=68.230.240.38; envelope-from=candtmallory@cox.net Received: from mallorydesktop ([68.1.92.51]) by eastrmmtao01.cox.net (InterMail vM.6.01.05.02 201-2131-123-102-20050715) with SMTP id <20060315213304.NDNJ4894.eastrmmtao01.cox.net@mallorydesktop> for ; Wed, 15 Mar 2006 16:33:04 -0500 Message-ID: <007f01c64878$0f6d6220$335c0144@mallorydesktop> From: "the mallorys" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: finding a radiator Date: Wed, 15 Mar 2006 15:33:11 -0600 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit 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 Thanks Ed, I'm waiting to get the 13B oil pan so I can determine exact space available, then the experiments begin. Chris ----- Original Message ----- From: "Ed Anderson" To: "Rotary motors in aircraft" Sent: Monday, March 13, 2006 11:00 PM Subject: [FlyRotary] Re: finding a radiator > Happen to find the spreadsheet for the exponential Horn duct (Attached). > You just plug in your inlet area, core area and distance from inlet to > core > numbers. The formula assumes a square or circular inlet/core area. If > you > have a rectangular one then you may need to treat each side length as a > square to get the coordinates you need. Like I said I have no data on the > effectiveness of this duct coordinate system. > > Ed > > ----- Original Message ----- > From: "the mallorys" > To: "Rotary motors in aircraft" > Sent: Monday, March 13, 2006 9:55 PM > Subject: [FlyRotary] Re: finding a radiator > > >> Looks like there will be some experimenting in my future. >> >> Ed, >> >> Do you have any more info on the exponential horn? I would need >> coordinates, formulas, drawing, or something, then I could make a trial >> run of all three and see which is most efficient. >> >> Chris >> ----- Original Message ----- >> From: "Ed Anderson" >> To: "Rotary motors in aircraft" >> Sent: Monday, March 13, 2006 8:11 PM >> Subject: [FlyRotary] Re: finding a radiator >> >> >>>I could never find any information on the efficiency of the Wedge >>>diffuser >>>at subsonic speeds. However, you are correct about the streamline duct. >>>Measure from the core forward then truncate where you have to. Here is >>>the way it appears to me, approx 1/2 of the streamline ducts pressure >>>recover is due to the length of the duct walls the other 1/2 is due to >>>the >>>trumpet style flair near the core. So say you completely eliminated the >>>duct and just had the flair then you would get approx 42% pressure >>>recovery (not terrible good). So if you could incorporate 1/2 of the >>>duct >>>length then you would be closer to a 62% pressure recovery (getting >>>better). These are just rough estimates, but I have been please with >>>the >>>truncated streamline duct. >>> >>> There is another similar duct coordinate system call the exponential >>> horn >>> that is easier to scale for shorter duct lengths. It appears to be >>> based >>> on the same concept of the streamline of keeping the air velocity rather >>> high until the a last minute flair of the duct to get pressure recovery. >>> It would appear that it's efficiency would be close to the streamline >>> and >>> its ease of calculation might make it worth the effort alone. But, >>> again >>> I have not been able to find any actually data on pressure recovery. >>> >>> If I do another cooling duct experiment, it will be using the >>> exponential >>> horn duct just to see how it works. But, not today {:>) >>> >>> Ed >>> >>> Ed Anderson >>> Rv-6A N494BW Rotary Powered >>> Matthews, NC >>> eanderson@carolina.rr.com >>> ----- Original Message ----- >>> From: "rijakits" >>> To: "Rotary motors in aircraft" >>> Sent: Monday, March 13, 2006 8:43 PM >>> Subject: [FlyRotary] Re: finding a radiator >>> >>> >>>> If I got the idea right, to use the Streamline you would want to sketch >>>> the >>>> "perfect" streamline for your radiator and then measure FROM the >>>> radiator >>>> towards the intake - whatever length you can do, and cut it there. >>>> That will be your intake area..... >>>> >>>> Wedge should be simple: Whatever your opening is - constant cross-area >>>> to >>>> the radiator - as big a radius at the bottom near end as you can >>>> justify - >>>> same point top surface, start a tapper to the end of the radiator to >>>> end >>>> about 1/2" above the far end and radius it down. >>>> >>>> Which one is better? No idea! >>>> Generally I would guess streamline, but in your case it will not be >>>> perfect, >>>> so you might want to do some mockup from plywood/cardboard/etc. and try >>>> some >>>> watermanometer tests/kitchenscale on the rooftop on top of your car - >>>> tests..... >>>> >>>> Thomas J. >>>> >>>> PS: PL over at the "other" site was lofting both systems together, >>>> looks >>>> good but results are anyones guess.... >>>> >>>> ----- Original Message ----- >>>> From: "the mallorys" >>>> To: "Rotary motors in aircraft" >>>> Sent: Monday, March 13, 2006 10:25 AM >>>> Subject: [FlyRotary] Re: finding a radiator >>>> >>>> >>>>> Dennis, >>>>> >>>>> You seem to be at the same point in installation as I. I'm putting >>>>> the >>>>> Renesis in an RV-8 using the James cowl. I'm trying to fit the >>>>> radiator >>>>> verticaly under the engine mount. That gives me space of about 8 1/2 >>>>> by >>>> 19 >>>>> 1/2. Make the radiator 3.75 to 4 inches thick, and I should have >>>>> enough >>>>> cooling. Since I don't have about 50 inches in front of the radiator >>>>> for >>>>> the perfect streamlined diffuser, the question for me is which will be >>>> less >>>>> drag, a shorter (about 20 inches) streamline, or tipping the radiator >>>>> at >>>> an >>>>> angle and using a wedge shape diffuser? In any case, I plan on having >>>>> an >>>>> exit duct also with a controllable exit. >>>>> >>>>> Does anyone know the answer? >>>>> >>>>> Chris >>>>> ----- Original Message ----- >>>>> From: "Ernest Christley" >>>>> To: "Rotary motors in aircraft" >>>>> Sent: Sunday, March 12, 2006 10:37 PM >>>>> Subject: [FlyRotary] Re: finding a radiator >>>>> >>>>> >>>>> > Dennis Haverlah wrote: >>>>> > >>>>> >> My question is - will the air make the 75 degree turn and flow >>>>> >> through >>>>> >> the fins? If not - would turning vanes below the radiator make >>>>> >> this >>>>> >> configuration possible? >>>>> > >>>>> > Dennis, a section in K&W book discusses this very issue. The short >>>> answer >>>>> > is "Yes". The long answer is that you have to be very careful how >>>>> > you >>>>> > design the duct face in front of the radiator. If you have their >>>>> > book, >>>>> > it's figure 12-12 on page 277. >>>>> > >>>>> > -- >>>>> > This is by far the hardest lesson about freedom. It goes against >>>>> > instinct, and morality, to just sit back and watch people make >>>>> > mistakes. We want to help them, which means control them and their >>>>> > decisions, but in doing so we actually hurt them (and ourselves)." >>>>> > >>>>> > >>>>> > -- >>>>> > Homepage: http://www.flyrotary.com/ >>>>> > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >>>>> >>>>> >>>>> -- >>>>> Homepage: http://www.flyrotary.com/ >>>>> Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >>>> >>>> >>>> -- >>>> Homepage: http://www.flyrotary.com/ >>>> Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >>>> >>> >>> >>> >>> -- >>> Homepage: http://www.flyrotary.com/ >>> Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >> >> >> -- >> Homepage: http://www.flyrotary.com/ >> Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >> > -------------------------------------------------------------------------------- > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >