X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [66.219.56.253] (HELO mail.qnsi.net) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3610319 for flyrotary@lancaironline.net; Wed, 29 Apr 2009 10:07:09 -0400 Received-SPF: none receiver=logan.com; client-ip=66.219.56.253; envelope-from=bhughes@qnsi.net Return-Receipt-To: "Bobby J. Hughes" MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C9C8DC.31A41BEE" Subject: RE: [FlyRotary] Re: Mocal Oil Cooler ECD54-182 Disposition-Notification-To: "Bobby J. Hughes" Content-class: urn:content-classes:message X-MimeOLE: Produced By Microsoft Exchange V6.5 Date: Wed, 29 Apr 2009 09:07:19 -0600 Message-ID: <74120FDE88CAFE4DBDA8814BCE20A3F30D85BA@qnsi-mail.qnsi.net> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [FlyRotary] Re: Mocal Oil Cooler ECD54-182 Thread-Index: AcnIm05iDbQPR2pMQdCdgKXD4HySRAANkUog References: From: "Bobby J. Hughes" To: "Rotary motors in aircraft" This is a multi-part message in MIME format. ------_=_NextPart_001_01C9C8DC.31A41BEE Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Al, =20 Temp readings are measured with my Advanced EMS, factory calibrated and seem to be within 1 deg of accuracy. Water is measured at the engine out water neck. Hottest point in the coolant system. The oil is measured after the oil cooler at the oil filter bypass pad. Coolest part of the oil system. I added an EM3 about a month ago just before my DAR inspection. I only connected the EGT, WP, OP, O2 and serial connection to the EC2 for final tuning and first flight. I plan to used the EM3 water temp to measure water after the last radiator \ engine in. Also the EM3 oil temp to measure before the oil cooler / engine out. Two CHT channels will also be used. One at the exit of the first radiator and one at the entrance of the second radiator. This will provide delta t information for all heat exchangers.=20 =20 which would suggest a very low coolant flow rate; much oversized rad =20 I suspect both. Both rad's are dual pass but are 1.25" hose. Rad's and inlet size should handle a three rotor. At the time I still had hope a three rotor renesis would be in the new RX7.=20 Speaking of a 3 rotor renesis. http://www.rx7club.com/showthread.php?t=3D740607 =20 =20 =20 Either it has not come to steady-state, or perhaps the temp measurements are suspect =20 I discovered that with the cowl off (70-80 OAT) I can't get the oil warn enough to stabilized the engine for tuning. Stuffing carpet in the inlets will brings the temps up but slowly. With lower cowl only I can easily control the temps for tuning. I have made multiple ground runs for two hours at a time with a lot of time spent in the middle to upper rpm range. My airport neighbors willing to do just about anything to get me in the air ASAP. :) =20 What accounts for the big change with and without the cowl? =20 =20 Airflow across the radiators. They sit outside the engine profile and back against the firewall. They get a lot of air without the cowl. With full cowl I suspect they see very little if any airflow. They do better when taxing but I don't remember what I was seeing or how heat soaked it was before taxing. If my strange tuning issue gets resolved I hope to have flight data to present at the Spring Rotor Fest.=20 =20 So the first rad removes most engine coolant heat. Oil / water exchanger transfers oil heat back to coolant. Second rad removes the oil heat + from the coolant. Water rad's should have a very high delta t. At least that's how I think it's working. The additional measurements points will be interesting to see. =20 =20 Bobby (Working on Spring Rotor Fest announcement. Should have it out this week.) ________________________________ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen Sent: Wednesday, April 29, 2009 12:52 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Mocal Oil Cooler ECD54-182 =20 I have the largest (ECD54-329) plumbed between two 400 ci water radiators. I can tell you it is very effective. With my cowling off, extended full power ground runs I see oil temp trailing water temps by 40-50 degrees. Where are you taking the temp measurements for the oil and water? Under these conditions, the water is heating the oil. If heat is being transferred from oil to water, the water at the exit of the first rad would need to be 60-70 degrees lower than the inlet; which would suggest a very low coolant flow rate; much oversized rad; or something suspect. Either it has not come to steady-state, or perhaps the temp measurements are suspect. Or; there is something suspect about my understanding of setup. =20 With lower cowl only, same conditions, the oil tracks the water a little closer. 20-40 degrees. With full cowl the temps come up together and stay together after about 170 degrees.=20 What accounts for the big change with and without the cowl? =20 Al G =20 !=20 ------_=_NextPart_001_01C9C8DC.31A41BEE Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable
Al,
 
Temp readings are measured with my Advanced = EMS,=20 factory calibrated and seem to be within 1 deg of accuracy. Water is = measured at=20 the engine out water neck. Hottest point in the coolant system. The oil = is=20 measured after the oil cooler at the oil filter bypass pad. Coolest part = of the=20 oil system. I added an EM3 about a month ago just before my DAR = inspection. I=20 only connected the EGT, WP, OP, O2 and serial connection to the EC2 for = final=20 tuning and first flight. I plan to used the EM3 water temp to measure = water=20 after the last radiator \ engine in. Also the EM3 oil temp to measure = before the=20 oil cooler / engine out. Two CHT channels will also be used. One at the = exit of=20 the first radiator and one at the entrance of the second radiator. This = will=20 provide delta t information for all heat exchangers.=20
 
which=20 would suggest a very low coolant flow rate; much oversized=20 rad
 
I suspect both. Both rad's are dual pass = but are=20 1.25" hose. Rad's and inlet size should handle a three rotor. At the = time I=20 still had hope a three rotor renesis would be in the new = RX7.=20
Speaking of a 3 rotor renesis.  = http://www.rx7club.com/showthread.php?t=3D740607 
 
 
Either it has not come to steady-state, or perhaps the temp = measurements=20 are suspect
 
I=20 discovered that with the cowl off  (70-80 OAT) I can't get the oil = warn=20 enough to stabilized the engine for tuning. Stuffing carpet in the = inlets will=20 brings the temps up but slowly. With lower cowl only I can easily = control the=20 temps for tuning. I have made multiple ground runs for two hours at a = time with=20 a lot of time spent in the middle to upper rpm range. My airport = neighbors=20 willing to do just about anything to get me in the air=20 ASAP. :)
 

What = accounts for=20 the big change with and without the cowl?

 

 

Airflow across the radiators. They sit = outside the=20 engine profile and back against the firewall. They get a lot of air = without the=20 cowl. With full cowl I suspect they see very little if any airflow. They = do=20 better when taxing but I don't remember what I was seeing or how heat = soaked it=20 was before taxing. If my strange tuning issue gets resolved I hope to = have=20 flight data to present at the Spring Rotor Fest.
 
So=20 the first rad removes most engine coolant heat. Oil / water exchanger = transfers=20 oil heat back to coolant. Second rad removes the oil heat + from = the=20 coolant. Water rad's should have a very high delta t. At least = that's how I=20 think it's working. The additional measurements points will be = interesting=20 to see. 
 
Bobby
(Working on Spring Rotor Fest announcement. = Should have=20 it out this week.)

From: Rotary motors in aircraft=20 [mailto:flyrotary@lancaironline.net] On Behalf Of Al=20 Gietzen
Sent: Wednesday, April 29, 2009 12:52 AM
To: = Rotary=20 motors in aircraft
Subject: [FlyRotary] Re: Mocal Oil Cooler=20 ECD54-182

 

I have the=20 largest (ECD54-329) plumbed between two 400 ci water radiators. I can = tell you=20 it is very effective. With my cowling off, extended full power ground = runs I see=20 oil temp trailing water temps by 40-50 degrees.

Where are = you taking=20 the temp measurements for the oil and water? Under these conditions, the = water=20 is heating the oil. If heat is being transferred from oil to water, the = water at=20 the exit of the first rad would need to be 60-70 degrees lower than the = inlet;=20 which would suggest a very low coolant flow rate; much oversized rad; or = something suspect. Either it has not come to steady-state, or perhaps = the temp=20 measurements are suspect. Or; there is something suspect about my = understanding=20 of setup.

 

With lower=20 cowl only, same conditions, the oil tracks the water a little closer. = 20-40=20 degrees. With full cowl the temps come up together and stay together = after about=20 170 degrees.

What = accounts for=20 the big change with and without the cowl?

 

Al=20 G

 

!=20

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