X-Virus-Scanned: clean according to Sophos on Logan.com X-PolluStop-Diagnostic: (direct reply)\eX-PolluStop-Score: 0.00\eX-PolluStop: Scanned with Niversoft PolluStop 2.1 RC1, http://www.niversoft.com/pollustop Return-Path: Received: from [216.52.245.18] (HELO ispwestemail2.mdeinc.com) by logan.com (CommuniGate Pro SMTP 4.3c4) with ESMTP id 862571 for flyrotary@lancaironline.net; Fri, 08 Apr 2005 20:39:17 -0400 Received-SPF: none receiver=logan.com; client-ip=216.52.245.18; envelope-from=wschertz@ispwest.com Received: from 7n7z201 (unverified [63.13.186.30]) by ispwestemail2.mdeinc.com (Vircom SMTPRS 4.1.361.0) with SMTP id for ; Fri, 8 Apr 2005 17:38:17 -0700 Message-ID: <004601c53c9c$6af36d30$6401a8c0@7n7z201> From: "William" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Ed Anderson Cooling System Date: Fri, 8 Apr 2005 19:38:10 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0041_01C53C72.7EC73550" 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 This is a multi-part message in MIME format. ------=_NextPart_000_0041_01C53C72.7EC73550 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hey Ed, before you change ducts, how about making the delta-T = measurements on the water side of the two coolers, and then repeating = with the measurments with each change in duct. I think we can learn = something fromthe data. Bill Schertz KIS Cruiser # 4045 ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Friday, April 08, 2005 2:09 PM Subject: [FlyRotary] Re: Ed Anderson Cooling System Hi Doug, No doubt when you have different (higher?) standards they can be = tougher to meet {:>). I agree with you assessment about a "reverse venturi" duct. I have = a larger "capture area" before the one duct necks down to 10 sq inches = and the other to 18 sq inches. My theory was that would increase the = velocity (dynamic pressure potential) to help maintain that higher dome = of pressure in front of the core that my radical curved duct walls = infringe on. My inlet is 6" long on one side and 3" long on the other, = so did not have a lot of room to play duct with. I flew a max power/climb take off two days ago with the ground OAT was = 85F, by the time I hit 3000 MSL the oil temp was up to 210F and the = coolant to 220F (my personal maxs for short duration). I then leveled = off and let the cooling system catch up with heat load. So it does = appear that for mid summer operation a bit more inlet area is called = for. I intend to open up the 10sq inch side (which is on my hottest = radiator - first in the series) to 18 sq inches as well. That will = provide a bit more margin on those hottest days. My personal experience = with the 91 turbo block and the Teflon coat silicon coolant "O" rings = that even coolant temps of 240F for short periods do not appear to have = done any harm - as you say, coolant and combustion chamber are still = separate. But, I am please with the experiment in that I believe for my HP = engine (I estimate 175-180HP) I have found a "lower" limit on duct size. = Although perhaps with "exhaust augmentation" it could be made to work = fine in hotter days - much easier just to open one duct up a bit. I total agree, when approaching trees or a ridge line - who cares = about the temps - can always replace the engine (if necessary) provided = you clear the tree line. It always a personal pleasure to exchange ideas, experiences and = theories with people of the calibrate we have on this list. I always = report my happenings - even when they are a bit embarrassing at times. = I seem to have had an unusually assortment of events happen. I was = awarded the Rotary Round Up "Lightening strikes six times (or more) = award which lists a litany of things from oil pump key drop out, front = tire gauges on both sides by the bolts holding on the wheel pant when I = screwed them in a bit too much and then planted the front tire a bit = hard causing it to balloon out and catch the bolts, flop tube drop off = resulting in a 12 miles engine out glide, etc, etc. =20 But one of the main reasons I share - is life is too short to make = all the mistakes yourself, so my objective is IF you are going to make = mistakes - advance the state of the art and make one I haven't - we = already know how those turned out{:>). Thanks for the comments, Doug. We try our best - and what's great is = when you're wrong, folks will bring it to you attention - in a pleasant = manner. Tomorrow I launch (weather permitting) heading down to join Tracy = Crook and on to Lakeland, Fl for Sun & Fun hope to see a bunch of your = folks down there. Best Regards Ed ----- Original Message -----=20 From: Shearbond@aol.com=20 To: Rotary motors in aircraft=20 Sent: Friday, April 08, 2005 11:05 AM Subject: [FlyRotary] Ed Anderson Cooling System In a message dated 4/4/05 6:05:09 PM Mountain Daylight Time, = eanderson@carolina.rr.com writes: There were those who claimed that there was no way that would = work. Well, I reduced my inlet area from 48 sq inch to 28 and it works = just fine thank you. Tracy Crook can vouch that I have flown with the = small openings for well over a year and he has never seen steam or smoke = coming from my engine - yet {:>). Hey Ed...that was probably me! All my analysis uses Military Air = outside conditions (+40 deg F over standard conditions), are climbing at = 100 mph TAS (near max rate of climb) and assumes that you are actually = generating 200 HP. At 2,000 ASL and +40 deg F over standard....I = suspect you are not generating 200HP and if you are indeed capable of = 200 HP probably do not maintain that operating condition sufficiently = long (at 100 mph) to reach steady state conditions which my rules of = thumb consider. =20 Hopefully if you ever are approaching the trees on T/O under the = more severe conditions you can tolerate 245+ deg F engine out coolant = temperature. Been there done that with the Mooney. You know what? The = throttle stayed in WOT and no leaves on the belly! It defined "pucker" = for me. So you'll have to forgive me if I size my inlets just a little = bit larger for our 95 deg summer days. (Military Air at sea level is 99 = deg F)...WOT...generating 200 HP for an extended period!! Do what Tracy = "noodles" and spray water on the heat exchangers!! Of course you have = to carry that two gallons of water around for the inevitable situation = :>). Sort of like a "gear up...not if, but when...if one flys enough. Incidentally we unavoidably reached those 245 deg F engine out = temperatures while developing my friends system without "apparent" ill = effects. He does not have sufficient hours to determine if there were = long term effects, but water and oil are still separate! Being a little = experienced with automotive tests I would estimate that short of rapid = temperature "shock" at those temperatues, no damage was done. Note: = one of the OEM Automotive tests of heads/head gaskets is to dump just = above freezing water into the engine inlet side of the waterpump while = running at full tilt!! That is thermal stress! SWAG (valuable engineering tool), I believe you have what is almost = a reverse venturi duct and your "effective" inlet area is actually = larger than 28 sq. in. which is probably your smallest area in the inlet = duct. I have "noodled" (another valuable engineering tool!) that what = you are doing might very effectively compensate for a very short inlet = duct....but probably is a small detriment to cooling drag. Too small to = matter IMO. Hey, you are a terrific experimenter and an invaluable Hummmmmer = flyer who is willing to share even at the risk of us "still building" = asking questions trying to understand what is happening in the Big RW. = It is terrific you share so we can consider what you have done and if we = are smart....will try to implement same in our own builds. I truly appreciate your combination of theory, practical application = and ability to write!! Thanks! Doug in CO ------=_NextPart_000_0041_01C53C72.7EC73550 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hey Ed, before you change ducts, how about making the delta-T = measurements=20 on the water side of the two coolers, and then repeating with the = measurments=20 with each change in duct.  I think we can learn something fromthe=20 data.
Bill Schertz
KIS Cruiser # 4045
----- Original Message -----
From:=20 Ed=20 Anderson
Sent: Friday, April 08, 2005 = 2:09=20 PM
Subject: [FlyRotary] Re: Ed = Anderson=20 Cooling System

Hi Doug,
 
No doubt when you have different (higher?) standards they can be = tougher=20 to meet {:>).
 
  I agree with you assessment about a "reverse venturi" = duct. =20 I have a larger "capture area" before the one duct necks down to 10 sq = inches=20 and the other to 18 sq inches.  My theory was that would increase = the=20 velocity (dynamic pressure potential) to help maintain that higher = dome of=20 pressure in front of the core that my radical curved duct walls = infringe=20 on.  My inlet is 6" long on one side and 3" long on the other, so = did not=20 have a lot of room to play duct with.
 
I flew a max power/climb take off two days ago with the ground = OAT was=20 85F, by the time I hit 3000 MSL the oil temp was up to 210F and the = coolant to=20 220F (my personal maxs for short duration).  I then leveled off = and let=20 the cooling system catch up with heat load.  So it does appear = that for=20 mid summer operation a bit more inlet area is called for.  I = intend to=20 open up the 10sq inch side (which is on my hottest radiator - first in = the=20 series) to 18 sq inches as well.  That will provide a bit more = margin on=20 those hottest days.  My personal experience with the 91 turbo = block and=20 the Teflon coat silicon coolant "O" rings that even coolant temps of = 240F for=20 short periods do not appear to have done any harm - as you say, = coolant and=20 combustion chamber are still separate.
 
But, I am please with the experiment in that I believe for my HP = engine=20 (I estimate 175-180HP) I have found a "lower" limit on duct = size. =20 Although perhaps with "exhaust augmentation" it could be made to work = fine in=20 hotter days - much easier just to open one duct up a bit.
 
I total agree, when approaching trees or a ridge line - who cares = about=20 the temps - can always replace the engine (if necessary) provided you = clear=20 the tree line.
 
It always a personal pleasure to exchange ideas, experiences and = theories=20 with people of the calibrate we have on this list.  I always = report my=20 happenings - even when they are a bit embarrassing at times.  I = seem to=20 have had an unusually assortment of events happen.  I was awarded = the=20 Rotary Round Up "Lightening strikes six times (or more) award which = lists a=20 litany of things from oil pump key drop out, front tire gauges on both = sides=20 by the bolts holding on the wheel pant when I screwed them in a bit = too much=20 and then planted the front tire a bit hard causing it to balloon out = and catch=20 the bolts, flop tube drop off resulting in a 12 miles engine out = glide, etc,=20 etc. 
 
But one of the main reasons I share -  is life is too short = to make=20 all the mistakes yourself, so my objective is IF you are going to make = mistakes - advance the state of the art and make one I haven't - we = already=20 know how those turned out{:>).
 
Thanks for the comments, Doug.  We try our best - and what's = great=20 is when you're wrong, folks will bring it to you attention - in a = pleasant=20 manner.
 
Tomorrow I launch (weather permitting) heading down to join Tracy = Crook=20 and on to Lakeland, Fl for Sun & Fun hope to see a bunch of your = folks=20 down there.
 
Best Regards
 
Ed
 
----- Original Message -----
From:=20 Shearbond@aol.com
To: Rotary motors in = aircraft=20
Sent: Friday, April 08, 2005 = 11:05=20 AM
Subject: [FlyRotary] Ed = Anderson=20 Cooling System

In a message dated 4/4/05 6:05:09 PM Mountain Daylight Time, eanderson@carolina.rr.com=20 writes:
There were those who claimed that = there was=20 no way that would work.  Well, I reduced my inlet area from = 48 sq=20 inch to 28 and it works just fine thank you.  Tracy Crook can = vouch=20 that I have flown with the small openings for well over a year and = he has=20 never seen steam or smoke coming from my engine - yet=20 {:>).
Hey Ed...that was probably me!  All my analysis uses = Military Air=20 outside conditions (+40 deg F over standard conditions), are = climbing=20 at 100 mph TAS (near max rate of climb) and assumes that you = are=20 actually generating 200 HP.  At 2,000 ASL and +40 deg F over=20 standard....I suspect you are not generating 200HP and if you = are=20 indeed capable of 200 HP probably do not maintain that operating = condition=20 sufficiently long (at 100 mph) to reach steady state conditions = which=20 my rules of thumb consider. 
 
Hopefully if you ever are approaching the trees on = T/O under the=20 more severe conditions you can tolerate 245+ deg F engine out = coolant=20 temperature.  Been there done that with the Mooney.  You = know=20 what?  The throttle stayed in WOT and no leaves on the = belly!  It=20 defined "pucker" for me.  So you'll have to forgive me if I = size my=20 inlets just a little bit larger for our 95 deg summer days.  = (Military=20 Air at sea level is 99 deg F)...WOT...generating 200 HP for an = extended=20 period!!  Do what Tracy "noodles" and spray water on the heat=20 exchangers!!  Of course you have to carry that two gallons of = water=20 around for the inevitable situation :>).  Sort of like a = "gear=20 up...not if, but when...if one flys enough.
 
Incidentally we unavoidably reached those 245 deg F engine out=20 temperatures while developing my friends system without "apparent" = ill=20 effects.  He does not have sufficient hours to determine if = there were=20 long term effects, but water and oil are still = separate!  Being a=20 little experienced with automotive tests I would estimate that short = of=20 rapid temperature "shock" at those temperatues, no damage was = done. =20 Note:  one of the OEM Automotive tests of heads/head gaskets is = to dump=20 just above freezing water into the engine inlet side of the = waterpump while=20 running at full tilt!!  That is thermal stress!
 
SWAG (valuable engineering tool), I believe you have what is = almost a=20 reverse venturi duct and your "effective" inlet area is actually = larger than=20 28 sq. in. which is probably your smallest area in the inlet = duct.  I=20 have "noodled" (another valuable engineering tool!) that what you = are doing=20 might very effectively compensate for a very short inlet = duct....but=20 probably is a small detriment to cooling drag.  Too small to = matter=20 IMO.
 
Hey, you are a terrific experimenter and an invaluable = Hummmmmer flyer=20 who is willing to share even at the risk of us "still building" = asking=20 questions trying to understand what is happening in the Big = RW. =20 It is terrific you share so we can consider what you have done = and if=20 we are smart....will try to implement same in our own builds.
 
I truly appreciate your combination of theory, practical = application=20 and ability to write!!  Thanks!
 
Doug in CO
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