X-Virus-Scanned: clean according to Sophos on Logan.com From: "Bill Bradburry" Received: from vms173017pub.verizon.net ([206.46.173.17] verified) by logan.com (CommuniGate Pro SMTP 6.1.2) with ESMTPS id 7702191 for flyrotary@lancaironline.net; Wed, 20 May 2015 10:17:05 -0400 Received-SPF: pass receiver=logan.com; client-ip=206.46.173.17; envelope-from=bbradburry@verizon.net Received: from Desktop ([71.164.185.6]) by vms173017.mailsrvcs.net (Oracle Communications Messaging Server 7.0.5.32.0 64bit (built Jul 16 2014)) with ESMTPA id <0NON00D5CJNCZO80@vms173017.mailsrvcs.net> for flyrotary@lancaironline.net; Wed, 20 May 2015 09:16:26 -0500 (CDT) X-CMAE-Score: 0 X-CMAE-Analysis: v=2.1 cv=E6x6fhYN c=1 sm=1 tr=0 a=20weQFHSdBTlwctzPCQ/Gw==:117 a=kUPQlYmSbg0A:10 a=o1OHuDzbAAAA:8 a=oR5dmqMzAAAA:8 a=-9mUelKeXuEA:10 a=h1PgugrvaO0A:10 a=r77TgQKjGQsHNAKrUKIA:9 a=9iDbn-4jx3cA:10 a=cKsnjEOsciEA:10 a=gZbpxnkM3yUA:10 a=Ia-xEzejAAAA:8 a=vU9mo1Ws-Oe058gZ_SMA:9 a=1V2XLC7OqNSUY-8T:21 a=kQRBoY2Mp6cDF7Xc:21 a=CjuIK1q_8ugA:10 a=SSmOFEACAAAA:8 a=6AoLbPU1lz-EKQ8iOzAA:9 a=G-Ti-B0evhYhVrEc:21 a=gKO2Hq4RSVkA:10 a=UiCQ7L4-1S4A:10 a=hTZeC7Yk6K0A:10 a=frz4AuCg-hUA:10 To: "'Rotary motors in aircraft'" References: In-reply-to: Subject: RE: [FlyRotary] Re: Return to Flight - 2 Date: Wed, 20 May 2015 09:16:25 -0500 Message-id: MIME-version: 1.0 Content-type: multipart/alternative; boundary="----=_NextPart_000_0009_01D092DD.A6539E70" X-Mailer: Microsoft Office Outlook 11 Thread-index: AdCSyiEXUv2CLUvzT6+Pjx97lDngrAAPCnHQ X-MIMEOLE: Produced By Microsoft MimeOLE V6.0.6002.18463 This is a multi-part message in MIME format. ------=_NextPart_000_0009_01D092DD.A6539E70 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Steve, That is a great chart! Amazing what you can learn with a little data. At the end of the test, it looks like you revved the engine up to 5000, then 5500, then 6000 for a couple of minutes and the temp seemed to stabilize at about 205 for both water and oil. Is this where your test engine runs with only prop air to cool it? What kind of HP do you think the turbo Renesis is doing at 6000? That seems like a really good cooling system to cool what is probably over 200 HP with just the prop blast. Do you think it would do that if cowled? Bill _____ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] Sent: Wednesday, May 20, 2015 1:56 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Return to Flight - 2 Jeff, Thank you for posting the photo and description. My comment concerning the effectiveness of the thermostat in the Mazda oil cooler was with respect to keeping the temperature of the oil returned to the engine from being too cold as opposed to keeping it from getting too high. The initial "C" on the side of the aircraft and the attention to sourcing cabin heat indicates to me that keeping the oil temperature up may be a concern at times. As the oil temperature rises, the Mazda oil thermostat doesn't open. Instead, it forces oil to pass through the core by closing a passage. That passage initially allowed most of the cool oil to bypass the core. The thermostat attempts to keep the oil temperature leaving the cooler at about 160 degrees. If the OAT is such that the Mazda oil cooler is capable of maintaining the 160 degrees, the second oil cooler downstream of it will drop the oil temperature considerably lower than this. As a result, the temperature of the oil returning to the engine will be lower than intended and vary with OAT. Where are your oil and coolant temperature sensors located? The restrictive nature of the Mazda oil cooler is not good for several reasons: At RPM capable of maintaining flight, at least 6 gal/min of oil is being pressurized to about 150 psi and then dumped through a restriction directly back to the oil pan. This consumes mechanical energy and puts additional heat into the oil. Also, for a given amount of heat transferred to the oil by the engine (given power setting) and a given temperature of the oil returned to the engine (say 160 degrees), cutting the oil flow rate through the coolers in half requires approximately a doubling of the drop in oil temperature produced by the coolers. This means that the oil temperature in the pan is significantly higher than it needs to be. Finally, the higher pressure and temperature of the oil at the oil pump outlet may increase wear of the pump, drive chain, and sprockets as well as increase the risk of failure of the hose connecting the oil pump outlet to the oil cooler as well as increase the risk of failure of the front cover o-ring. I don't know if the Mazda oil cooler had been installed when your hose failed. I have attached a plot of the interaction of the coolant and oil systems for a Renesis engine on my test stand. The ducting for the oil cooler and radiator are completely separate and not enclosed in a cowling. The air flow through each them is generated by the prop slip stream and controlled by a door in each exit duct. With the doors positioned such that the oil and coolant were both reasonably stable at about 210 degrees, the radiator door was then opened fully and the oil cooler door was left unchanged. This resulted in a coolant temperature drop of about 60 degrees and a corresponding oil temperature drop of at least 20 degrees (the oil temperature was still decreasing). Then, with the doors again positioned to give about 210 degree oil and coolant temperatures, the oil cooler door was fully opened and the radiator door left unchanged. This resulted in a oil temperature drop of about 50 degrees and a corresponding coolant temperature drop of about 10 degrees. I would expect a similar oil and coolant interaction for a 13B. These are just my observations and I leave it to you to decide if the interaction is significant enough to be useful. Steve Boese RV6A, 1986 13B NA, RD1A, EC2 _____ From: Rotary motors in aircraft on behalf of Jeff Whaley Sent: Tuesday, May 19, 2015 2:36:44 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Return to Flight - 2 Hi Steve: The photo from May 8 was of previous setup and that BLUE HOSE (Twist-Tite) is what departed my engine 3 years ago . that heat box was installed during winter months . attached is a photo of right-side, present-day setup. The Cabin heat will now be scavenged off the radiator outlet plenum -look below the oil cooler. My Fluidyne oil coolers (DB-30416?) are only 2/3 size of your DB-30618. I'm not sure why the Mazda oil cooler will not aid in oil temperature control as it seems to be doing so at present. During ground runs the Mazda cooler is cold while the Fluidyne is warm . during both flights so far, the oil temperature was stable at 160F while the water temperature rose to 210F; after shutdown the temperature of both oil coolers was the same as discerned by touch, so at some point the Mazda thermostat must have opened. I wish I could drive over and talk to you in-person as it's hard to get all these details down in writing . I like having extra oil cooling as excessive oil temperature can damage the oil seals; excessive water temperature is not good but the lesser of two evils. The 13B is odd in that the two fluid temperatures seem to be very disconnected. I've managed to get control over the oil but not the water so far; however, from previous readings I believe even if the water jacket temperature was cooler that it would not necessarily mean a reduction in oil cooling capacity could be achieved - I have never experienced that luxury. Jeff Wag-Aero 2+2, 1988 13B NA, RD-1C, EC2 ------=_NextPart_000_0009_01D092DD.A6539E70 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

Steve,

 

That is a great chart!  = Amazing what you can learn with a little data.

 

At the end of the test, it looks = like you revved the engine up to 5000, then 5500, then 6000 for a couple of = minutes and the temp seemed to stabilize at about 205 for both water and oil.  = Is this where your test engine runs with only prop air to cool it?  What = kind of HP do you think the turbo Renesis is doing at 6000?  That seems = like a really good cooling system to cool what is probably over 200 HP with = just the prop blast.  Do you think it would do that if = cowled?

 

Bill

 

From: = Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
Sent: Wednesday, May 20, = 2015 1:56 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = Return to Flight - 2

 

 

Jeff,

 

Thank you for = posting the photo and description.

 

My comment = concerning the effectiveness of the thermostat in the Mazda oil cooler was = with respect to keeping the temperature of the oil returned to the engine = from being too cold as opposed to keeping it from getting too high.  The = initial "C" on the side of the aircraft and the attention to sourcing cabin heat indicates to me that keeping the oil temperature up = may be a concern at times.

 

As the oil = temperature rises, the Mazda oil thermostat doesn't = open.   Instead, it forces oil to pass through the core by closing a passage. = That passage initially allowed most of the cool oil to bypass the core.  = The thermostat attempts to keep the oil temperature leaving the cooler = at about 160 degrees.  If the OAT is such that the Mazda oil cooler is capable of maintaining the 160 degrees, the second oil cooler downstream = of it will drop the oil temperature considerably lower than this.  As a = result, the temperature of the oil returning to the engine will be lower than = intended and vary with OAT.

 

Where are = your oil and coolant temperature sensors located?

 

The = restrictive nature of the Mazda oil cooler is not good for several reasons:  =

 

At RPM = capable of maintaining flight, at least 6 gal/min of oil is being pressurized to = about 150 psi and then dumped through a restriction directly back to the oil = pan.  This consumes mechanical energy and puts additional heat into = the oil. 

 

Also, for= a given amount of heat transferred to the oil by the engine (given power = setting) and a given temperature of the oil returned to the engine (say 160 degrees), cutting the oil flow rate through the coolers in half requires approximately a doubling of the drop in oil = temperature produced by the coolers.  This means that the oil temperature in = the pan is significantly higher than it needs to = be.

 

Finally, the = higher pressure and temperature of the oil at the oil pump outlet may increase = wear of the pump, drive chain, and sprockets as well as increase the risk of = failure of the hose connecting the oil pump outlet to the oil cooler as well as = increase the risk of failure of the front cover o-ring.  I don't know = if the Mazda oil cooler had been installed when your hose failed.   

 

I have = attached a plot of the interaction of the coolant and oil systems for a Renesis engine = on my test stand.  The ducting for the oil cooler and radiator are = completely separate and not enclosed in a cowling.  The air flow through each = them is generated by the prop slip stream and controlled by a door in each = exit duct. 

 

With = the doors positioned such that the oil and coolant were both reasonably stable at = about 210 degrees, the radiator door was then opened fully and the oil cooler = door was left unchanged.  This resulted in a coolant temperature = drop of about 60 degrees and a corresponding oil temperature drop of at = least 20 degrees (the oil temperature was still = decreasing).  

 

Then, with = the doors again positioned to give about 210 degree oil and coolant temperatures, the oil cooler door was fully opened and the radiator = door left unchanged.  This resulted in a oil temperature drop of about = 50 degrees and a corresponding coolant temperature drop of about 10 = degrees.

 

I would = expect a similar oil and coolant interaction for a 13B.  These are just my observations and I leave it to you to decide if the interaction is significant enough to be useful.

 

Steve Boese

RV6A, 1986 13B NA, RD1A, EC2

 

  &n= bsp;        

From: = Rotary motors in aircraft <flyrotary@lancaironline.net> on behalf of Jeff Whaley <flyrotary@lancaironline.net>
Sent: Tuesday, May 19, = 2015 2:36:44 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = Return to Flight - 2

 

Hi = Steve:

The photo = from May 8 was of previous setup and that BLUE HOSE (Twist-Tite) is what departed = my engine 3 years ago …  that heat box was installed during = winter months … attached is a photo of right-side, present-day = setup.  The Cabin heat will now be scavenged off the radiator outlet plenum = –look below the oil cooler.  My Fluidyne oil coolers (DB-30416?) are only = 2/3 size of your DB-30618.  I’m not sure why the Mazda oil cooler = will not aid in oil temperature control as it seems to be doing so at = present.  During ground runs the Mazda cooler is cold while the Fluidyne is warm = … during both flights so far, the oil temperature was stable at 160F while = the water temperature rose to 210F; after shutdown the temperature of both = oil coolers was the same as discerned by touch, so at some point the Mazda thermostat must have opened.  I wish I could drive over and talk to = you in-person as it’s hard to get all these details down in writing  …  I like having extra oil cooling as excessive oil temperature can damage the oil seals; excessive water temperature is not = good but the lesser of two evils.

The 13B is = odd in that the two fluid temperatures seem to be very disconnected. =  I’ve managed to get control over the oil but not the water so far; however, = from previous readings I believe even if the water jacket temperature was = cooler that it would not necessarily mean a reduction in oil cooling capacity = could be achieved -  I have never experienced that = luxury.

Jeff<= /font>

Wag-Aero = 2+2, 1988 13B NA, RD-1C, EC2

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