X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from ms-smtp-02.southeast.rr.com ([24.25.9.101] verified) by logan.com (CommuniGate Pro SMTP 5.1c.2) with ESMTP id 1231118 for flyrotary@lancaironline.net; Mon, 10 Jul 2006 13:44:47 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-111-186.carolina.res.rr.com [24.74.111.186]) by ms-smtp-02.southeast.rr.com (8.13.6/8.13.6) with SMTP id k6AHhxNs014691 for ; Mon, 10 Jul 2006 13:44:01 -0400 (EDT) Message-ID: <001901c6a448$750ee9b0$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Temperature control Date: Mon, 10 Jul 2006 13:44:12 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0016_01C6A426.EDA78890" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0016_01C6A426.EDA78890 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable ----- Original Message -----=20 From: James Maher=20 To: Rotary motors in aircraft=20 Sent: Monday, July 10, 2006 1:28 PM Subject: [FlyRotary] Temperature control The setup: =B7 Engine/Model/Year: 13B 6 port NA mixed=20 =B7 Source Condition: David Atkins Rebuilt for Aviation = Application =20 =B7 Modifications: Ported intakes and cooling for 180HP=20 =B7 Intake: Atkins short manifold w/TWM 48mm Throttle body=20 =B7 Exhaust: 321 SS tangential muffler=20 =B7 Engine Control: RWS EC2=20 =B7 Fuel Control: 4 Mazda 460cc Injectors, pri. in block & sec = in manifold =B7 Fuel Pumps: RWS=20 =B7 Cooling System: 2 - 9"x13"GM evaporator cores with 0.75" = auto hose, stock water pump with 180F deg.-thermostat, 50/50 = glycol\water mix. =B7 Oil System: stock 1986 oil cooler=20 =B7 Installation: conventional - self built mount =B7 PSRU/Re-Drive: Ross 2.85:1=20 =B7 Prop: IVO Magnum 74" 45-105"pitch in-flight adjustable =B7 Power: 180HP? =20 The issue: On the ground, cooling stabilizes at 180-190F deg and oil is usually = 10 degrees below the cooling with an OAT of 65-70F deg. When running with higher OAT (75-85F deg) after about 0.5 hours of = moderate taxi runs (up to 4300RPM) the cooling temps reach 212Fdeg with = the oil about 200F deg. =20 The question: Can something be done to get lower operating temperatures without = redesigning the system? Would switching to pure water help and if so by how much? Would removing the thermostat help and if so by how much? How much change should I expect if I were to do both? You guys down south should have a good idea of how best to enhance = cooling. What are your suggestions? Thanks, Jim Maher(Dyke Delta) Hi James, Welcome to the club, cooling appears to always be the first item of = business. I can not quantify the differences those changes you propose = would make. However, a 50/50 coolant mixture has a 40% lower specific heat than = pure water alone. Meaning it will not carry as much heat away at the = same coolant temperature. Would pure water give you 40% more cooling - = I personally doubt it, would it help, I believe it certainly would. I fly without a thermostat and my normal (60-70 F OAT) temps are 160F = for coolant and oil at cruise. On a hot day, right after take off, I = may hit 200F on the oil and 220F on the coolant for a short duration. = With a thermostat, your coolant temps are going to go right up to the = thermostat limits shortly after starting your engine - after all that is = what a thermostat does. But, still at moderate rpm of 4300 on a 60-70F = day, I would like for the coolant and oil not to exceed 200F. I fly without a thermostat to remove any flow restriction as well as = permitting my temps to stay below any thermostat limit if conditions = permit. Since I get acceptable temperatures when flying I am satisfied = without a thermostat. In winter, the temps do run a bit cool, but then = I can tape off a bit of the core and get higher temps. Ed That's my 0.02 worth Ed ------=_NextPart_000_0016_01C6A426.EDA78890 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
----- Original Message -----
From:=20 James=20 Maher
Sent: Monday, July 10, 2006 = 1:28 PM
Subject: [FlyRotary] = Temperature=20 control

The setup:
=B7       =20 Engine/Model/Year: 13B 6 port NA mixed =
=B7       =20 Source Condition: David Atkins Rebuilt = for=20 Aviation Application =20
=B7       =20 Modifications: Ported intakes and = cooling for=20 180HP
=B7       =20 Intake: Atkins short manifold w/TWM = 48mm=20 Throttle body
=B7       =20 Exhaust: 321 SS tangential muffler=20
=B7       =20 Engine Control: RWS EC2 =
=B7       =20 Fuel Control: 4 Mazda 460cc Injectors, = pri. in=20 block & sec in manifold
=B7       =20 Fuel Pumps: RWS
=B7       =20 Cooling System: 2 =96 9=94x13=94GM = evaporator cores=20 with 0.75=94 auto hose, stock water pump with 180F deg.-thermostat, = 50/50=20 glycol\water mix.
=B7       =20 Oil System: stock 1986 oil cooler=20
=B7       =20 Installation: conventional =96 self = built=20 mount
=B7       =20 PSRU/Re-Drive: Ross 2.85:1 =
=B7       =20 Prop: IVO Magnum 74" 45-105=94pitch = in-flight=20 adjustable
=B7       =20 Power: 180HP? 
 
The issue:
On the ground, cooling stabilizes at 180-190F deg and oil is = usually 10=20 degrees below the cooling with an OAT of 65-70F deg.
When running with higher OAT (75-85F deg) after about 0.5 = hours of=20 moderate taxi runs (up to 4300RPM) the cooling temps reach 212Fdeg = with the=20 oil about 200F deg.
 
The question:
Can something be done to get lower operating temperatures = without=20 redesigning the system?
Would switching to pure water help and if so by how = much?
Would removing the thermostat help and if so by how = much?
How much change should I expect if I were to do = both?
You guys down south should have a good idea of how best to = enhance=20 cooling.
What are your suggestions?
Thanks,
Jim Maher(Dyke Delta)
 
 
Hi James,
 
Welcome to the club, cooling appears to always = be the=20 first item of business.   I can not quantify the differences = those=20 changes you propose would make.
 
However, a 50/50 coolant mixture has a 40% = lower=20 specific heat than pure water alone.  Meaning it will not carry = as much=20 heat away at the same coolant temperature.  Would pure water give = you 40%=20 more cooling - I personally doubt it, would it help, I believe it = certainly=20 would.
 
I fly without a thermostat and my normal = (60-70 F OAT)=20 temps are 160F for coolant and oil at cruise.  On a hot day, = right after=20 take off, I may hit 200F on the oil and 220F on the coolant for a = short=20 duration.  With  a thermostat, your coolant temps are = going to=20 go right up to the thermostat limits shortly after starting your = engine -=20 after all that is what a thermostat does.  But, still at moderate = rpm of=20 4300 on a 60-70F day, I would like for the coolant and oil not to = exceed=20 200F.
 
I fly without a thermostat to remove any flow=20 restriction as well as permitting my temps to stay below any = thermostat limit=20 if conditions permit.  Since I get acceptable temperatures when = flying I=20 am satisfied without a thermostat.  In winter, the temps do run a = bit=20 cool, but then I can tape off a bit of the core and get higher=20 temps.
 
Ed
 
 
That's my 0.02 worth
 
Ed
 
 
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