Return-Path: <13brv3@bellsouth.net> Received: from imf24aec.mail.bellsouth.net ([205.152.59.72] verified) by logan.com (CommuniGate Pro SMTP 4.1.4) with ESMTP id 2603430 for flyrotary@lancaironline.net; Thu, 25 Sep 2003 11:49:39 -0400 Received: from rad ([68.212.13.204]) by imf24aec.mail.bellsouth.net (InterMail vM.5.01.05.27 201-253-122-126-127-20021220) with ESMTP id <20030925154938.GDRC1810.imf24aec.mail.bellsouth.net@rad> for ; Thu, 25 Sep 2003 11:49:38 -0400 From: "Russell Duffy" <13brv3@bellsouth.net> To: "'Rotary motors in aircraft'" Subject: BUC's diet- cooling Date: Thu, 25 Sep 2003 10:49:38 -0500 Message-ID: <000001c3837c$a058bfa0$0201a8c0@rad> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C38352.B782B7A0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.4510 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C38352.B782B7A0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable I see you have a new cowl on order. I was wondering exactly what configuration for cooling do you have in mind? I presume the two = evaporator core approach is just not configuration compatible with all you need to = put under the cowling. One thing, my brief experiment with reducing the = inlet size by 33% tells me, is that contouring the flow from inlet to radiator does indeed make a significant difference in cooling performance. =20 =20 You're asking this to get revenge for my silly EDDIE questions, aren't = you :-) =20 The honest answer is that I don't yet know what cooling configuration = I'll use. About the only thing I've decided is that I can use the stock = cowl, and save myself the torture of having to make one from scratch. I have probably considered every conceivable option for cooling over the past couple weeks, and really have only a few options now. My ideal goal = would be to use the stock cowl, with as little change as possible. =20 =20 It will take 4-6 weeks to get the cowl, so I'll try to use that time to = do some cooling tests, and primarily, more turbo evaluation. I'll really = need to decide if the turbo stays, or goes before making the next cowl. =20 =20 For water, I'll either use two of the Caprice evap cores, or a smaller = Howe radiator. Oil will be cooled with my current Setrab cooler, and an intercooler will be a bonus item, if I can fit it in. =20 =20 If the turbo goes, the best option is to use the evap cores in the = cheeks, and the oil cooler on the bottom of the engine with a small scoop. Air, = and an exhaust pipe would exit the bottom of the cowl, and I'd put the = normal cheek extensions on the fuselage to clean up the rear of the cheeks. =20 =20 If the turbo stays, I've got 2 similar options in mind. =20 =20 1a- Use a Howe radiator, with the oil cooler on top, tucked as tightly = to the bottom of the engine mount as possible, positioned at the far aft = end of the mount. Bring air in the front of the cowl cheeks as normal, close = off the rear of the cheeks, and let the air flow out through the oil cooler = and radiator. I would have to make a sort of rear facing scoop for the = bottom of the radiator, to dump the air toward the rear, in about the normal = air exit location. This would probably be the best aerodynamic option, but = of course has the complication of sealing the cowl, and worrying that the = hot air from the turbo area will reduce the efficiency of the radiator too = much. =20 1b- This would be just like above, except that a scoop would be mounted = on the bottom of the cowl to bring air in, and the rear of the cheeks would = be opened for air exit. The front of the cheeks would be ducted to the = turbo intake, and maybe an intercooler. The main downside to this option is = the drag from not having the cheek extensions in place. =20 =20 I would plan to make the cowl seal to the radiator, then have a = removable scoop. Doing that, I could actually try option A first, then go to = option B if cooling is a problem. The downside of this is not having room for an exhaust pipe to exit the bottom if I ever remove the turbo. =20 =20 Now, if you actually made it this far, you're sorry you asked right? =20 Rusty (too much to think about) ------=_NextPart_000_0001_01C38352.B782B7A0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message
I see you have a new cowl on = order.  I=20 was wondering exactly what configuration for cooling do you have in = mind? =20 I presume the two evaporator core approach is just not configuration = compatible=20 with all you need to put under the cowling.  One thing, my brief = experiment=20 with reducing the inlet size by 33% tells me, is that contouring the = flow from=20 inlet to radiator does indeed make a significant difference in cooling=20 performance.   
 
You're asking this to get revenge for my = silly EDDIE=20 questions, aren't you :-)
 
The honest answer is that I don't yet know = what cooling=20 configuration I'll use.  About the only thing I've decided is that = I can=20 use the stock cowl, and save myself the torture of having to make one = from=20 scratch.  I have probably considered every conceivable option for = cooling=20 over the past couple weeks, and really have only a few options = now. =20 My ideal goal would be to use the stock cowl, with as little change = as=20 possible. 
 
It will take 4-6 weeks to get the cowl, so = I'll try to=20 use that time to do some cooling tests, and primarily, more turbo=20 evaluation.  I'll really need to decide if the turbo stays, or goes = before=20 making the next cowl.  
 
For water, I'll either use two of the Caprice = evap=20 cores, or a smaller Howe radiator.  Oil will be cooled with my = current=20 Setrab cooler, and an intercooler will be a bonus item, if I can fit it=20 in. 
 
If the turbo goes, the best option is to use = the evap=20 cores in the cheeks, and the oil cooler on the bottom of the engine with = a small=20 scoop.  Air, and an exhaust pipe would exit the bottom of the cowl, = and I'd=20 put the normal cheek extensions on the fuselage to clean up the rear of = the=20 cheeks.  
 
If the turbo stays, I've = got 2 similar=20 options in mind. 
 
1a- Use a Howe radiator, with the oil cooler = on top,=20 tucked as tightly to the bottom of the engine mount as possible, = positioned at=20 the far aft end of the mount.  Bring air in the front of the = cowl=20 cheeks as normal, close off the rear of the cheeks, and let the air flow = out=20 through the oil cooler and radiator.  I would have to make a sort = of=20 rear facing scoop for the bottom of the radiator, to dump the=20 air toward the rear, in about the normal air exit location.  = This=20 would probably be the best aerodynamic option, but of course has the=20 complication of sealing the cowl, and worrying that the hot air = from the=20 turbo area will reduce the efficiency of the radiator too=20 much.  
 
1b- This would be just like above, except = that a scoop=20 would be mounted on the bottom of the cowl to bring air in, and the rear = of the=20 cheeks would be opened for air exit.  The front of the cheeks would = be=20 ducted to the turbo intake, and maybe an intercooler.  The main = downside to=20 this option is the drag from not having the cheek extensions in = place. =20
 
I would plan to make the cowl seal to = the=20 radiator, then have a removable scoop.  Doing that, I could = actually try=20 option A first, then go to option B if cooling is a problem.  The = downside=20 of this is not having room for an exhaust pipe to exit the bottom if I = ever=20 remove the turbo. 
 
Now, if you actually made it this far, you're = sorry you=20 asked right?
 
Rusty (too much to think=20 about)
------=_NextPart_000_0001_01C38352.B782B7A0--