X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from lrcmmta07-srv.windstream.net ([166.102.165.79] verified) by logan.com (CommuniGate Pro SMTP 5.3.2) with ESMTP id 4103659 for flyrotary@lancaironline.net; Fri, 29 Jan 2010 12:46:23 -0500 Received-SPF: pass receiver=logan.com; client-ip=166.102.165.79; envelope-from=montyr2157@windstream.net Return-Path: X-WS-COS: WSOB804 X-Cloudmark-Category: Undefined:Undefined X-Cloudmark-Analysis: v=1.1 cv=ecdOkNdtVPLgVbkhqcSXJ/lc5roehzTLvWeiyxU9UNk= c=1 sm=0 a=WUKWvh78jHwA:10 a=Ia-xEzejAAAA:8 a=oCcaPWc0AAAA:8 a=xv3j8CLgWi_ZKgWS7loA:9 a=a54z1WkznV4IxtfPUFIA:7 a=cEojG7b8hBOneajNk2W-fxHCp4YA:4 a=EzXvWhQp4_cA:10 a=SSmOFEACAAAA:8 a=yMhMjlubAAAA:8 a=5kgCHx-JAAAA:8 a=kDp6qqAjthyUMc3n7BoA:9 a=jVqH2ZujL1DrC-OXSVsA:7 a=K__GcdEFE1IkxikES8eBF3aSFE0A:4 a=d-1ze5jHbJEA:10 a=BPCOYmGL8QAA:10 a=aYmXFaDsvdUtdcjyLRK/+g==:117 X-Cloudmark-Score: 0 Authentication-Results: lrcmmta07 smtp.user=montyr2157; auth=pass (LOGIN) Received: from [98.20.138.133] ([98.20.138.133:60469] helo=newbox) by lrcmmta07 (envelope-from ) (ecelerity 2.2.2.45 r()) with ESMTPA id 5F/9E-13616-CCE136B4; Fri, 29 Jan 2010 11:45:49 -0600 Message-ID: From: "MONTY ROBERTS" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Tiff to CAD Software Date: Fri, 29 Jan 2010 11:45:49 -0600 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00AB_01CAA0D8.99F9DE70" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5843 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 This is a multi-part message in MIME format. ------=_NextPart_000_00AB_01CAA0D8.99F9DE70 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable T Mann, Just wanting to make sure you had run some numbers and were not just = scaling the p51 installation.=20 As long as the inlet and exit sizes are in the ball park and your = radiators are the right size it should be fine in flight. You may have ground cooling issues. The p51 did and it had the prop in = front of the scoop. I think Al had to add a fan for ground ops. I'd keep that in mind. I think the p51 style scoop is a good idea. You should have better = pressure recovery than the submerged inlets. Should be able to take = advantage of a thicker radiator and lower cooling air flow and thus = lower drag. Should be able to control cooling air flow with a variable = exit. You might also consider taking your induction air from the = boundary layer bleed area to further reduce drag.=20 Also keep in mind that the p51 design is pre Kucheman and Webber. The = K&W streamline diffuser is superior to the standard style and easier to = construct. The p51 diffuser is kind of a hybrid that was probably done = by trial and error and a lot of testing. Plus the need for the splitter = to the oil cooler changes things. Don't ever assume that a = "professional" design was created with a super computer and is perfect. = Especially one in a wartime development environment. I tell you this as = a "professional" development person. And you don't need much more than a = "bar napkin" to design this. Cad is helpful after the napkin stage. I think you are being wise in making it easy to swap out diffuser = sections. Cooling the exhaust is an issue. I would allow room for a heat shield. = Plugs up with the exhaust centered in the cooling outlet with the = cooling airflow surrounding it would be ideal from this standpoint. = However, it might cause other problems that you don't want to deal with = (engine mount, oil return etc.). I don't remember how far along you are = or what engine you are using. Like I said...not trying to rain on your parade, just trying to save you = a lot of work and heartache if you hadn't done your homework. Sounds = like you have. Even so, I promise the likelihood of it being perfect on the first try = is vanishingly small ;-) looking forward to some pics.=20 Monty ----- Original Message -----=20 From: Thomas Mann=20 To: Rotary motors in aircraft=20 Sent: Friday, January 29, 2010 11:12 AM Subject: [FlyRotary] Re: Tiff to CAD Software Monty, I get the impression that you think this is about 'P-51 envy' or = something. =20 For starters, the P-51 style scoop is part of the original plans. = That's per Burt. I have seen where many have opted for the NACA style = scoop but the more I look into it the more sense the original plans = method makes to me. =20 The sizing-to-hp has already been calculated to the best of my ability = using the available resources. That is a part of the equation that can = be applied to any approach and is an important foundation. =20 The biggest issue I have centers around a good diffuser and cooling = exhaust arrangement. To this point, I have heard all sorts of theories = and various 'bar napkin' graphics but the original P-51 drawings are the = only source I have found for a professionally engineered and proven = product. That said, I feel most comfortable pursuing this approach as a = solution for my project. Because the drawings have been converted to = CAD, the calculations can be performed in a more accurate fashion and = the design altered prior to printing templates. I'll have more on that = later. =20 The biggest difference in my approach vs. what others have done in the = past is that I am documenting everything as I go and will make that = documentation as well as the CAD drawings available for others to = analyze as a possible approach. =20 Another advantage of reviewing the P-51 drawings is that it has = altered my approach to implementing the design. I anticipate the scoop = being composed of three segment. A front section starting just forward of the oil cooler and the = portion aft of that point being divided into a top and bottom section. =20 =20 By building it this way, I can rebuild various configurations of the = air inlet and swap them out with very little down time.=20 =20 One of the big differences in my project vs. other canard aircraft is = the fact that I have an area behind the rear seat (hell hole) that is = available to me. I can actually tuck part of my radiator into this area = and avoid at least some of the projection of the scoop as it relates to = the profile. =20 As is the case with the original P-51 design, the exhaust doors for = both the radiator and the oil cooler are in-flight adjustable. =20 =20 All that said, there comes a point where the research stops and = production begins. I would be very surprised if this turns out to be a = hit on the first shot, but it should be very close.=20 =20 T Mann =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of MONTY ROBERTS Sent: Friday, January 29, 2010 10:18 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Tiff to CAD Software =20 Thomas, =20 Not trying to rain on your parade, but why do you think that something = designed to cool a 1500 hp WW2 fighter at speeds over 300 mph and then = scaled to fit in your airframe is what you need for your application? =20 You should calculate what your particular situation needs and go from = there. The math is not that hard, in fact I think Ed has a spreadsheet = he would probably be willing to share if you asked nicely. I think he = would even run some numbers for you. If you want to make it look like = the P51 installation fine, but size all the radiators, inlets and exits = for your speed, altitude and power levels. Then draw the P51 like scoop = around that and see if it still fits. =20 1.) determine how much HP you plan to make continuously. 2.) figure out how much heat will be rejected at that HP. 3.) figure out how fast your airplane will go with that much HP. 4.) size inlet and exit accordingly. 5.) Check over range of altitudes repeat step 4 and 5. 6.) look at hot day takeoff and climb. size max exit opening for that. 7.) compare your results to the other flying examples closest to your = application for a sanity check 8.) If you are the outlier you better understand why or start over =20 I would look very closely at what Al G has done as well as others = successfully flying canard aircraft with rotaries. They have much more = in common with your application than the P51. =20 Monty =20 -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.432 / Virus Database: 271.1.1/2655 - Release Date: = 01/29/10 09:08:00 ------=_NextPart_000_00AB_01CAA0D8.99F9DE70 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
T Mann,
 
Just wanting to make sure you had run = some numbers=20 and were not just scaling the p51 installation.
 
As long as the inlet and exit sizes are = in the ball=20 park and your radiators are the right size it should be fine in=20 flight.
 
You may have ground cooling issues. The = p51 did and it had the prop in front of the scoop. I = think Al had=20 to add a fan for ground ops.
 
I'd keep that in mind.
 
I think the p51 style scoop is a = good=20 idea. You should have better pressure recovery than the submerged = inlets.=20 Should be able to take advantage of a thicker radiator and lower cooling = air=20 flow and thus lower drag. Should be able to control cooling = air flow=20 with a variable exit. You might also consider taking your = induction=20 air from the boundary layer bleed area to further reduce drag. =
 
Also keep in mind that the p51 design = is pre=20 Kucheman and Webber. The K&W streamline diffuser is superior to=20 the standard style and easier to construct. The p51 diffuser is kind of a hybrid that was probably done = by trial=20 and error and a lot of testing. Plus the need for the splitter to the = oil cooler=20 changes things. Don't ever assume that a "professional" design was = created with=20 a super computer and is perfect. Especially one in a wartime development = environment. I tell you this as a "professional" development person. And = you=20 don't need much more than a "bar napkin" to design this. Cad is helpful = after=20 the napkin stage.
 
I think you are being wise in making it = easy to=20 swap out diffuser sections.
 
Cooling the exhaust is an issue. I = would allow room=20 for a heat shield. Plugs up with the exhaust centered in the cooling = outlet with=20 the cooling airflow surrounding it would be ideal from this=20 standpoint. However, it might cause other problems that you = don't want=20 to deal with (engine mount, oil return etc.).  I don't = remember how=20 far along you are or what engine you are using.
 
Like I said...not trying to rain on = your parade,=20 just trying to save you a lot of work and heartache if you hadn't done = your=20 homework. Sounds like you have.
 
Even so, I promise the likelihood = of it=20 being perfect on the first try is vanishingly small =  ;-)
 
looking forward to some pics. =
 
Monty
----- Original Message -----
From:=20 Thomas = Mann=20
Sent: Friday, January 29, 2010 = 11:12=20 AM
Subject: [FlyRotary] Re: Tiff = to CAD=20 Software

Monty,

I=20 get the impression that you think this is about =91P-51 envy=92 or=20 something.

 

For=20 starters, the P-51 style scoop is part of the original plans. That=92s = per Burt.=20 I have seen where many have opted for the NACA style scoop but the = more I look=20 into it the more sense the original plans method makes to=20 me.

 

The=20 sizing-to-hp has already been calculated to the best of my ability = using the=20 available resources. That is a part of the equation that can be = applied to any=20 approach and is an important foundation.

 

The=20 biggest issue I have centers around a good diffuser and cooling = exhaust=20 arrangement. To this point, I have heard all sorts of theories and = various=20 =91bar napkin=92 graphics but the original P-51 drawings are the only = source I=20 have found for a professionally engineered and proven product. That = said, I=20 feel most comfortable pursuing this approach  as a solution for = my=20 project. Because the drawings have been converted to CAD, the = calculations can=20 be performed in a more accurate fashion and the design altered prior = to=20 printing templates. I=92ll have more on that = later.

 

The=20 biggest difference in my approach vs. what others have done in the = past is=20 that I am documenting everything as I go and will make that = documentation as=20 well as the CAD drawings available for others to analyze as a possible = approach.

 

Another=20 advantage of reviewing the P-51 drawings is that it has altered my = approach to=20 implementing  the design. I anticipate the scoop being composed = of three=20 segment.

A=20 front section starting just forward of the oil cooler and the portion = aft of=20 that point being divided into a top and bottom section. =20

 

By=20 building it this way, I can rebuild various configurations of the air = inlet=20 and swap them out with very little down time.

 

One=20 of the big differences in my project vs. other canard aircraft is the = fact=20 that I have an area behind the rear seat (hell hole) that is available = to me.=20 I can actually tuck part of my radiator into this area and avoid at = least some=20 of the projection of the scoop as it relates to the=20 profile.

 

As=20 is the case with the original P-51 design, the exhaust doors for both = the=20 radiator and the oil cooler are in-flight adjustable.=20  

 

All=20 that said, there comes a point where the research stops and production = begins.=20 I would be very surprised if this turns out to be a hit on the first = shot, but=20 it should be very close.

 

T=20 Mann

 

From: Rotary = motors in=20 aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of = MONTY=20 ROBERTS
Sent: Friday, January 29, 2010 10:18 = AM
To: Rotary=20 motors in aircraft
Subject: [FlyRotary] Re: Tiff to CAD=20 Software

 

Thomas,

 

Not = trying to rain=20 on your parade, but why do you think that something designed to cool a = 1500 hp=20 WW2 fighter at speeds over 300 mph and then scaled to fit in your=20 airframe is what you need for your=20 application?

 

You should=20 calculate what your particular situation needs and go from there. = The=20 math is not that hard, in fact I think Ed has a spreadsheet he would = probably=20 be willing to share if you asked nicely. I think he would even run = some=20 numbers for you. If you want to make it look like the P51 installation = fine,=20 but size all the radiators, inlets and exits for your speed, altitude = and=20 power levels. Then draw the P51 like scoop around that and see if = it=20 still fits.

 

1.) = determine how=20 much HP you plan to make continuously.

2.) = figure out how=20 much heat will be rejected at that HP.

3.) = figure out how=20 fast your airplane will go with that much = HP.

4.) size = inlet and=20 exit accordingly.

5.) Check = over=20 range of altitudes repeat step 4 and 5.

6.) look = at hot day=20 takeoff and climb. size max exit opening for = that.

7.) = compare your=20 results to the other flying examples closest to your application for a = sanity=20 check

8.) If = you are the=20 outlier you better understand why or start = over

 

I would = look very=20 closely at what Al G has done as well as others successfully flying = canard=20 aircraft with rotaries. They have much more in common with your = application=20 than the P51.

 

Monty

 


No virus found in this incoming message.
Checked by AVG = -=20 www.avg.com
Version: 8.5.432 / Virus Database: 271.1.1/2655 - = Release=20 Date: 01/29/10 09:08:00
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