X-Virus-Scanned: clean according to Sophos on Logan.com From: "Jeff Whaley" Received: from hub026-NJ-7.exch026.serverdata.net ([206.225.166.170] verified) by logan.com (CommuniGate Pro SMTP 6.1.2) with ESMTPS id 7702170 for flyrotary@lancaironline.net; Wed, 20 May 2015 10:11:19 -0400 Received-SPF: none receiver=logan.com; client-ip=206.225.166.170; envelope-from=jwhaley@datacast.com Received: from MBX026-E1-NJ-2.exch026.domain.local ([10.240.14.52]) by HUB026-NJ-7.exch026.domain.local ([10.240.14.233]) with mapi id 14.03.0224.002; Wed, 20 May 2015 07:10:43 -0700 To: "Steven W. Boese" Subject: RE: [FlyRotary] Re: Return to Flight - 2 Thread-Topic: [FlyRotary] Re: Return to Flight - 2 Thread-Index: AQHQkuPUEX3Zx/UR2kazNwTsPpvzMZ2ExNjg Date: Wed, 20 May 2015 14:10:43 +0000 Message-ID: <234B758DE9A64449BEB6BB5D1345CA7A48EC95ED@mbx026-e1-nj-2.exch026.domain.local> References: <1432104961455.99353@uwyo.edu> In-Reply-To: <1432104961455.99353@uwyo.edu> Accept-Language: en-CA, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [209.87.232.162] Content-Type: multipart/alternative; boundary="_000_234B758DE9A64449BEB6BB5D1345CA7A48EC95EDmbx026e1nj2exch_" MIME-Version: 1.0 --_000_234B758DE9A64449BEB6BB5D1345CA7A48EC95EDmbx026e1nj2exch_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Hi Steve, thank you for another detailed explanation; I know you have done = a great deal of instrumentation on these engines and I appreciate your feed= back - those plots are priceless. My oil temperature probe is mounted at the return port after the second oil= cooler; my coolant temperature probe is mounted near the water pump outlet= . The Mazda oil cooler was NOT installed when the hose failed. So from your explanation, the Mazda oil cooler is not the best choice for a= viation use whether it's a single cooler or linked in series? It would not take too much effort (2-3 hours) for me to remove the Mazda co= oler and reinstall my second Fluidyne where it was previously mounted; I ke= pt the cowl openings the same and adapted the Mazda oil cooler install to f= it. I would have to go back to installing cover plates for winter operatio= ns to control oil temperature - I can live with that and with synthetic oil= , cool oil is not a huge issue. When I get the coolant temperature under control, time to re-experiment wit= h only one oil cooler - two is definitely overkill for winter operations. Jeff From: Steven W. Boese [mailto:flyrotary@lancaironline.net] Sent: Wednesday, May 20, 2015 2:56 AM Subject: Re: [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 t= he engine from being too cold as opposed to keeping it from getting too hig= h. The initial "C" on the side of the aircraft and the attention to sourci= ng 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. Inst= ead, it forces oil to pass through the core by closing a passage. That pass= age initially allowed most of the cool oil to bypass the core. The thermos= tat attempts to keep the oil temperature leaving the cooler at about 160 de= grees. If the OAT is such that the Mazda oil cooler is capable of maintain= ing the 160 degrees, the second oil cooler downstream of it will drop the o= il temperature considerably lower than this. As a result, the temperature = of the oil returning to the engine will be lower than intended and vary wit= h OAT. Where are your oil and coolant temperature sensors located? The restrictive nature of the Mazda oil cooler is not good for several reas= ons: At RPM capable of maintaining flight, at least 6 gal/min of oil is being pr= essurized to about 150 psi and then dumped through a restriction directly b= ack to the oil pan. This consumes mechanical energy and puts additional he= at into the oil. Also, for a given amount of heat transferred to the oil by the engine (give= n 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 re= quires approximately a doubling of the drop in oil temperature produced by = the coolers. This means that the oil temperature in the pan is significant= ly higher than it needs to be. Finally, the higher pressure and temperature of the oil at the oil pump out= let may increase wear of the pump, drive chain, and sprockets as well as in= crease the risk of failure of the hose connecting the oil pump outlet to th= e oil cooler as well as increase the risk of failure of the front cover o-r= ing. I don't know if the Mazda oil cooler had been installed when your hos= e failed. I have attached a plot of the interaction of the coolant and oil systems fo= r a Renesis engine on my test stand. The ducting for the oil cooler and ra= diator 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 reasonabl= y 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 tempera= ture drop of about 60 degrees and a corresponding oil temperature drop of a= t least 20 degrees (the oil temperature was still decreasing). Then, with the doors again positioned to give about 210 degree oil and cool= ant temperatures, the oil cooler door was fully opened and the radiator doo= r left unchanged. This resulted in a oil temperature drop of about 50 degr= ees 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 dur= ing 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 si= ze 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 gro= und runs the Mazda cooler is cold while the Fluidyne is warm ... during bot= h flights so far, the oil temperature was stable at 160F while the water te= mperature 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 m= ust 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; excessiv= e 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 disconnec= ted. I've managed to get control over the oil but not the water so far; ho= wever, from previous readings I believe even if the water jacket temperatur= e 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 This message, and the documents attached hereto, is intended only for the a= ddressee and may contain privileged or confidential information. Any unauth= orized disclosure is strictly prohibited. If you have received this message= in error, please notify us immediately so that we may correct our internal= records. Please then delete the original message. Thank you. --_000_234B758DE9A64449BEB6BB5D1345CA7A48EC95EDmbx026e1nj2exch_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Hi Steve, thank you for a= nother detailed explanation; I know you have done a great deal of instrumen= tation on these engines and I appreciate your feedback – those plots are priceless.

My oil temperature probe = is mounted at the return port after the second oil cooler; my coolant tempe= rature probe is mounted near the water pump outlet.  The Mazda oil cooler was NOT installed when the hose failed.=

So from your explanation,= the Mazda oil cooler is not the best choice for aviation use whether it= 217;s a single cooler or linked in series?

It would not take too muc= h effort (2-3 hours) for me to remove the Mazda cooler and reinstall my sec= ond Fluidyne where it was previously mounted; I kept the cowl openings the same and adapted the Mazda oil cooler install to fit.&nb= sp; I would have to go back to installing cover plates for winter operation= s to control oil temperature – I can live with that and with syntheti= c oil, cool oil is not a huge issue.

When I get the coolant te= mperature under control, time to re-experiment with only one oil cooler = 211; two is definitely overkill for winter operations.

Jeff

 <= /p>

From: Steven W= . Boese [mailto:flyrotary@lancaironline.net]
Sent: Wednesday, May 20, 2015 2:56 AM
Subject: Re: [FlyRotary] Re: Return to Flight - 2<= /p>

 

 

Jeff,

 

Thank you for posting the photo and d= escription.

 

My comment concerning the effectivene= ss of the thermostat in the Mazda oil cooler was with respect to keepi= ng 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 s= ourcing cabin heat indicates to me that keeping the oil temperature up may = be a concern at times.

 

As the oil temperature rises, the Maz= da oil thermostat doesn't open.   Instead, it forc= es oil to pass through the core by closing a passage. That passage ini= tially 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 th= e 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 temper= ature sensors located?

 

The restrictive nature of the Mazda o= il 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 d= umped through a restriction directly back to the oil pan.  This consumes mechanical energy and puts additional heat into th= e oil. 

 

Also, for a given amount of heat= transferred to the oil by the engine (given power setting) and a given tem= perature 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.&nbs= p; This means that the oil temperature in the pan is significantly higher t= han it needs to be.

 

Finally, the higher pressure and temp= erature of the oil at the oil pump outlet may increase wear of the pump, dr= ive chain, and sprockets as well as increase the risk of failure of the hose connecting the oil pump outlet to the oil cooler as we= ll 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 h= ose failed.   

 

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

 

With the doors positioned such t= hat the oil and coolant were both reasonably stable at about 210 degrees, t= he 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 le= ast 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 c= ooler door was fully opened and the radiator door left unchanged. = ; This resulted in a oil temperature drop of about 50 degrees and a correspo= nding coolant temperature drop of about 10 degrees.<= /p>

 

I would expect a similar oil and cool= ant 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.

 

S= teve Boese

R= V6A, 1986 13B NA, RD1A, EC2

 

      &= nbsp;    

From: Rotary motors in aircraft <= flyrotary@lancaironline.net<= /a>> 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 m= y 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 t= o 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 tem= perature was stable at 160F while the water temperature rose to 210F; after shutdown the temperature of both oil coole= rs was the same as discerned by touch, so at some point the Mazda thermosta= t must have opened.  I wish I could drive over and talk to you in-pers= on as it’s hard to get all these details down in writing  …  I like having extra oil cooling as exc= essive oil temperature can damage the oil seals; excessive water temperatur= e 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 capaci= ty could be achieved -  I have never experienced that luxury.

Jeff

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

This message, and the documents attached hereto, is intended only for the a= ddressee and may contain privileged or confidential information. Any unauth= orized disclosure is strictly prohibited. If you have received this message= in error, please notify us immediately so that we may correct our internal records. Please then delete the origin= al message. Thank you. --_000_234B758DE9A64449BEB6BB5D1345CA7A48EC95EDmbx026e1nj2exch_--