X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-qy0-f204.google.com ([209.85.221.204] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3681464 for flyrotary@lancaironline.net; Sat, 13 Jun 2009 11:24:26 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.221.204; envelope-from=rwstracy@gmail.com Received: by qyk42 with SMTP id 42so3740184qyk.7 for ; Sat, 13 Jun 2009 08:23:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type; bh=x/hcABkSzdzWTgBMxzyfo+5N82oOZACoWjsV/0e54tQ=; b=JVeZBZPG6/DBlwJgAlMe87P8gOofsojY9YHJfUlyy+RBrdWBU85Fp2dpVH3LqRaeUG Aw8x3yW66cgQXbEH4/A5XGl6dZiryXbDNoaR+pYt9Fltk9185pBHBsRBN18rj3dUUnN6 6/qjj8cDV77irn4V/c9AR934o5JNSX1u+hzEY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=xl2oxDzB2fXcEM7pWIUx5f8kn4JxUwpXYaWT+GLtTEMyVGrDhShXnQysLLFyv5Pzsc urEy8qcdtYpK+8y+2B0XKpydeOuwmZPkNFBIgEv84EHGDMU65lgmCOhC4eBR2thR94nr 1dy7q9w7Ha8rNKmVlFX6I8famlX3WlY3IjlV0= MIME-Version: 1.0 Sender: rwstracy@gmail.com Received: by 10.224.2.85 with SMTP id 21mr5502402qai.262.1244906632466; Sat, 13 Jun 2009 08:23:52 -0700 (PDT) In-Reply-To: References: Date: Sat, 13 Jun 2009 11:23:52 -0400 X-Google-Sender-Auth: d800289f4c9fbe1f Message-ID: <1b4b137c0906130823w3bbb6c07wf59ac179c86f6a9d@mail.gmail.com> Subject: Re: [FlyRotary] Re: Water temps From: Tracy Crook To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=0015175cb8a09b5093046c3c69e1 --0015175cb8a09b5093046c3c69e1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit This is just an educated guess but to see if the critical engine temperature has been exceeded you might want to measure the temp of the rear rotor housing close to a sparkplug. I use a thermocouple at the knock sensor boss to do this. Coolant temp at the pump housing is pretty useless for this since it depends on coolant to be circulating to measure. Otherwise it is just measuring steam. Tracy Crook On Fri, Jun 12, 2009 at 10:57 PM, George Lendich wrote: > Lynn and Ed, > What I would like to know is where is the best place to read those heats to > stay within the parameters mentioned. > > Ideally one would look initially to water out of the engine and water going > into the engine, the same with oil, which to me would give a better > understand of the cooling capability. > > George (down under) > > The rotary is a sandwich of layers - end housing, rotor housing, center > housing, rotor housing, end housing. Not only are these dissimilar shapes, > they are also dissimilar metals and they have different thermal loads and > cooling passages. The center housing for instance, has the least room of > all the housings for coolant, yet has the greatest surface area exposed to > combustion. (Lucky iron has half the coefficient of thermal expansion > compared to aluminum, or maybe Mazda did that on purpose). On top of that, > the combustion and exhaust half of the cycle put a lot more heat into the > engine than the compression, and the intake actually cools it. When the > engine heats up (or cools off) all these parts heat and expand at different > rates. The water seals are sandwiched between these layers and somehow have > to deal with this. The hotter the engine gets, the greater the effect. > Those thin, fragile water seals get twisted and stretched, the damage is > cumulative, and you can't see it until suddenly you need an engine rebuild. > > 235 is too hot. If your coolant temp got to 235, consider yourself > fortunate you don't have to rebuild. A good temperature is 180-200, over > 200 is pushing it. You can run a little hotter in a plane because it's a > gentle, constant heat, not the abrupt sort of heat changes that kill car > motors. But not 40 degrees hotter. > > I think rotary-engine plane builders are going through a lot of the same > stuff the car tuners went through a decade or two ago. There are going to > be a lot of guys with blown water seals in a couple years, if everyone is > flying around with temps 210+ all the time. > > On Fri, Jun 12, 2009 at 7:09 AM, Ed Anderson wrote: > >> Point taken, Lynn. >> >> >> >> I guess I was impressed John could run it for 55 minutes and only get >> 235F. If I run mine for over 2-3 minutes at WOT my temps would already be >> climbing over 200F. While not necessarily recommending it for others, my >> red line for oil is 200F (into block) and 220F coolant (out of block). I >> normally do not stay at these temps beyond 2-3 minutes during take off and >> initial climbout. >> >> >> >> Ed Anderson >> >> Rv-6A N494BW Rotary Powered >> >> Matthews, NC >> >> eanderson@carolina.rr.com >> >> http://www.andersonee.com >> >> http://www.dmack.net/mazda/index.html >> >> http://www.flyrotary.com/ >> >> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >> >> http://www.rotaryaviation.com/Rotorhead%20Truth.htm >> ------------------------------ >> >> *From:* Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] *On >> Behalf Of *Lynn Hanover >> *Sent:* Friday, June 12, 2009 9:14 AM >> *To:* Rotary motors in aircraft >> *Subject:* [FlyRotary] Water temps >> >> >> >> Allow me to speculate: >> >> I suggest that watertemps above 210 are out of bounds. Thus it should be >> looked at as something you got away with, not a number to look for in normal >> operation. I would retorque the stack cold if I had seen those numbers. >> (235) >> >> Here is some dyno stuff for a 12A bridgeported engine with two 36MM chokes >> in a Weber carb. >> >> 6500 RPM (because there is no point in testing a racing engine below >> that), and even then it is to put up a starting point for a curve. >> >> Torque 139.6 foot pounds. >> >> HP 173.3 >> >> EGTs 1515 front 1491 rear >> >> BSFC .666 (the devils own) >> >> oil temp 162 (160 is ideal) Above 160 costs power due to rotor face >> temperatures. >> >> Oil pressure 99.9 (relief set at 110 pounds) >> >> Water temp is always 180 controlled by the cooling system on the dyno. >> >> Air/fuel 12.3 (slightly rich is fine as it helps cooling and sealing) >> >> I would expect to get as much as 10% more power from a 13B. >> >> Lynn E. Hanover >> >> Interesting questions: Is that data at full throttle? >> >> You can hold cruise RPM at an A/F of 15? >> >> >> >> >> >> Today I ran the engine .9 hour, .7th's static at 4700 rpm - 13B, Marcotte >> 2 - l redrive >> >> >> >> Water temp 235 OAT 61 Spring hasn't >> arrived above the 44th parallel >> >> oil temp 215 yet >> >> Exh. temp 1500 >> >> Prop speed 2350 >> >> MP 28 >> >> oil pres 75 >> >> air - fuel 15 to 1 >> >> fuel press 42 >> >> >> >> .2 hr high speed taxi >> >> >> >> Water temp 188 >> >> oil temp 160 >> >> Ex temp 1400 >> >> Prop speed 2500 >> >> MP 28 >> >> fuel press 42 >> >> >> >> The static engine run temperatures climbed quite a bit with the cowling on >> and working on the programming I didn't notice that this was happening, but >> they went right down when I idled back. >> >> I will have to pull the cowling in the morning and check the redrive, it >> appears the seal is leaking on the flywheel side. With no support from >> Marcotte, I may have too much 80w in the gearbox. I believe that the >> temperatures look good for flight. JohnD >> > > --0015175cb8a09b5093046c3c69e1 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable This is just an educated guess but to see if the critical engine temperatur= e has been exceeded you might want to measure the temp of the rear rotor ho= using close to a sparkplug.=A0 I use a thermocouple at the knock sensor bos= s to do this.=A0

Coolant temp at the pump housing is pretty useless for this since it de= pends on coolant to be circulating to measure.=A0 Otherwise it is just meas= uring steam.

Tracy Crook
=A0

O= n Fri, Jun 12, 2009 at 10:57 PM, George Lendich <lendich@aanet.com.au> wrot= e:
Lynn and Ed,
What I would like to know is where=A0i= s the best=20 place to read those heats to stay within the parameters=A0=20 mentioned.=A0
=A0
Ideally one would look initially to wa= ter out of=20 the engine and water going into the engine, the same with oil, which to me = would=20 give a better understand of the cooling capability.
=A0
George (down under)
The=20 rotary is a sandwich of layers - end housing, rotor housing, center housi= ng,=20 rotor housing, end housing.=A0 Not only are these dissimilar shapes, they= =20 are also dissimilar metals and they have different thermal loads and cool= ing=20 passages.=A0 The center housing for instance, has the least room of all t= he=20 housings for coolant, yet has the greatest surface area exposed to=20 combustion.=A0 (Lucky iron has half the coefficient of thermal expansion= =20 compared to aluminum, or maybe Mazda did that on purpose).=A0 On top of= =20 that, the combustion and exhaust half of the cycle put a lot more heat in= to=20 the engine than the compression, and the intake actually cools it. When t= he=20 engine heats up (or cools off) all these parts heat and expand at differe= nt=20 rates.=A0 The water seals are sandwiched between these layers and somehow= =20 have to deal with this.=A0 The hotter the engine gets, the greater the=20 effect.=A0 Those thin, fragile water seals get twisted and stretched, the= =20 damage is cumulative, and you can't see it until suddenly you need an= engine=20 rebuild.

235 is too hot.=A0 If your coolant temp got to 235,=20 consider yourself fortunate you don't have to rebuild.=A0 A good=20 temperature is 180-200, over 200 is pushing it.=A0 You can run a little= =20 hotter in a plane because it's a gentle, constant heat, not the abrup= t sort of=20 heat changes that kill car motors.=A0 But not 40 degrees hotter.

I= =20 think rotary-engine plane builders are going through a lot of the same st= uff=20 the car tuners went through a decade or two ago.=A0 There are going to be= a=20 lot of guys with blown water seals in a couple years, if everyone is flyi= ng=20 around with temps 210+ all the time.

On Fri, Jun 12, 2009 a= t 7:09 AM, Ed Anderson <eanderson@carolina.rr.com>= =20 wrote:

Point taken,=20 Lynn.

=A0

I guess I was=20 impressed John could run it for 55 minutes and only get 235F.=A0 If I r= un=20 mine for over 2-3 minutes at WOT my temps would already be climbing ove= r=20 200F.=A0 While not necessarily recommending it for others, my red line= =20 for oil is 200F (into block) and 220F coolant (out of block).=A0 I=20 normally do not stay at these temps beyond 2-3 minutes during take off = and=20 initial climbout.=A0

=A0

From:flyrotary@lancaironline.net] On Behalf Of Lynn Hanover
Sent: Friday, June 12, 2009 9:14=20 AM


To: Rotary motors in=20 aircraft
Subject:= =20 [FlyRotary] Water temps

=A0

Allow me to=20 speculate:

I suggest that watertemps above=20 210 are out of bounds. Thus it should be looked at as something you got= away=20 with, not a number to look for in normal operation. I would retorque th= e=20 stack cold if I had seen those numbers. (235)

Here is some dyno stuff for a=20 12A bridgeported engine with two 36MM chokes in a Weber=20 carb.

6500 RPM (because there is no=20 point in testing a racing engine below that), and even then it is to pu= t up=20 a starting point for a curve.

Torque 139.6 foot=20 pounds.

HP 173.3

EGTs 1515 front 1491=20 rear

BSFC .666 (the devils=20 own)

oil temp 162 (160 is ideal)=20 Above 160 costs power due to rotor face temperatures.

Oil pressure=A099.9 (relief=20 set at 110 pounds)

Water temp is always 180=20 controlled by the cooling system on the dyno.

Air/fuel=A0 12.3=A0=20 (slightly rich is fine as it helps cooling and sealing)

I would expect to get as much as=20 10% more power from a 13B.

Lynn E.=20 Hanover

Interesting questions: Is that=20 data at full throttle?

You can hold cruise RPM at an=20 A/F of 15?

=A0

=A0

Today I ran the engine .9 hour,=20 .7th's static at 4700 rpm -=A0 13B, Marcotte 2 - l=20 redrive

=A0

Water=20 temp=A0=A0=A0=A0=A0=A0=A0=A0=20 235=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 OAT=A0=20 61=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 Spring=20 hasn't arrived above the 44th parallel

oil=20 temp=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 215=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 yet

Exh.=20 temp=A0=A0=A0=A0=A0=A0=A0=A0=A01500

Prop=20 speed=A0=A0=A0=A0=A0=A0=A0 2350

MP=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=20 28

oil=20 pres=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 75

air -=20 fuel=A0=A0=A0=A0=A0=A0=A0=A0 15 to=20 1

fuel=20 press=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 42

=A0

.2 hr high speed=20 taxi

=A0

Water=20 temp=A0=A0=A0=A0=A0=A0=A0=A0=20 188

oil=20 temp=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 =A0=A0 160

Ex=20 temp=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 1400

Prop=20 speed=A0=A0=A0=A0=A0=A0=A0=A0=A02500

MP=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=20 28

fuel=20 press=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=20 42

=A0

The static engine run=20 temperatures climbed quite a bit with the cowling on and working on the= =20 programming I didn't notice that this was happening, but they went = right=20 down when I idled back.

I will have to pull the cowling=20 in the morning and check the redrive, it appears the seal is leaking on= the=20 flywheel side.=A0 With no support from Marcotte, I may have too much 80= w=20 in the gearbox.=A0 I believe that the temperatures look good for=20 flight.=A0=20 JohnD



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