X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=PbaBeRpd c=1 sm=1 tr=0 a=EG6Wxa21mlO1ov8RJXsCQg==:117 a=x7bEGLp0ZPQA:10 a=A-0mRrAPPO4A:10 a=y4yBn9ojGxQA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=3oc9M9_CAAAA:8 a=0qqORytXAAAA:8 a=7g1VtSJxAAAA:8 a=oisENYwj-6AcwBgCCzQA:9 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=q9tNnM8EeIYvKpk0iK0A:9 a=onaN5dYnkXc4vQ3Y:21 a=Urk15JJjZg1Xo0ryW_k8:22 a=Nj1bhqyGrdl6Az3_ctNx:22 a=grOzbf7U_OpcSX4AJOnl:22 From: "Charlie England ceengland7@gmail.com" Received: from mail-il1-f172.google.com ([209.85.166.172] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 614606 for flyrotary@lancaironline.net; Fri, 07 Aug 2020 10:35:09 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.166.172; envelope-from=ceengland7@gmail.com Received: by mail-il1-f172.google.com with SMTP id x1so1937577ilp.7 for ; Fri, 07 Aug 2020 07:35:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=VQjFiwDfIAIQ4JYKwgXrT+TClLuXE8/Aj0aQh+5I5Go=; b=gVBgzjqRGGYV3hf4yFioSPCV8WtkwHNv+tX3ngRleYZpTt2RBlfQYASDlua8lsrkQK 8DZbD8u/egobF2H6iPFnz3DUJvS4ldFd5I1XOO48h0gzQS7+2sB5ywSGg1eLF+Fk3hTh WVVvE5D/qIqA5S/10EjKY9etNw5nOQ+4MdkEm4EERMsy/uIjTcHCBqFhI6NaOyqo3OdL OHL9aArF6T2jMHayURi1VrwWr89dl/5hMD5G4DJD548O6iFZiULlz4gN18I1eAsOp9ZE QBnu8BjzWQ9ysHs0JBZ53FlK6lAnJ/pQiT9FeND/3hl3xXrXJFzj6LSA9RURgqznQJiL CWCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=VQjFiwDfIAIQ4JYKwgXrT+TClLuXE8/Aj0aQh+5I5Go=; b=SVAcFUe21lVDamzbbMgO4FzEUM/m+58nYjVY3Z0z38eMMYJXTg33n4GOklxAXvJWG6 kc+QqZ51Oih7gwLIrC3eZZ/6YuiIH06Zv/l6dVky3bTzFMNzaYRm+6remLtQDB3lVrWb 0VHsELjqbsdGHtsSJQuKlnMvvDCG1HKoPtFpU6yh6Jk2dn5lIMMYGcTzPZwxA7+qyNM/ usQGJjxWLHLv4tJi2vuEgsvHjAGXyFeKXlE/Qtsgagr3rXXYqR7aBFz1NmvRkg9ZF5K+ Ucp6CNSs1/MiVPZbIFegUxbQDnqTLttedkofgTxJWIsw39IwRn+LPhNg1l8zMxzPhGtx /nUg== X-Gm-Message-State: AOAM531kWc0gP7A+MqgUg5unU9SWGsywovLyZI4BlWtC9qMlkeHCWdGH CItk1t9ScZwGOCXPHJ28oIYGxAs/9huV3bVKlJaVnYC3 X-Google-Smtp-Source: ABdhPJwpucdMVKZcpd1PCr5S/5U6m1i1tQmQm6xv8YDx9K33kz+kg3d15fyBwRReCZNg+RdGcEHG8tMqki/G35l7OOE= X-Received: by 2002:a05:6e02:bf1:: with SMTP id d17mr4723931ilu.261.1596810891858; Fri, 07 Aug 2020 07:34:51 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: Date: Fri, 7 Aug 2020 09:34:05 -0500 Message-ID: Subject: Re: [FlyRotary] Re: Dyno Sheet To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="000000000000fb973a05ac4a819a" --000000000000fb973a05ac4a819a Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable That's curious. Are you saying that fuel flow *decreased* as rpm *increased* above 6750 rpm? And airspeed decreased, as well? The only way fuel flow should decrease as rpm increases is if the load on the engine is going down. Is the prop running out of pitch (or ability to absorb the HP) as you get faster? Is the airframe hitting a drag wall due to cooling drag (still shouldn't show a reduction in fuel flow; it just wouldn't go any faster)? What actual speeds are you achieving when this is happening? Refresh my memory; who's prop (what blades) is it? Do engine temps go up as you get above 6750 rpm? Think about the 'airplane as dyno' thing: If rpm continues to go up, and the drag (our substitute for torque on the engine brake in a real dyno) stays the same or increases, then power *must* be increasing, and so must fuel flow. Simple math; (torque*rpm)/5252. So, was the plane going downhill, or was the prop unable to absorb the additional power and decoupling, unloading the engine? Charlie On Fri, Aug 7, 2020 at 9:01 AM Stephen Izett stephen.izett@gmail.com < flyrotary@lancaironline.net> wrote: > Hi Guys. > > Today we did some engine data analysis at 9500, 7500, 6000 and 4500 feet > agl. > WOT with constant best power mixture of 0.9 Lambda. > We looked at Fuel Flow and IAS at 5500,5750,6000,6250,6500,6750 & 7000rpm= . > The data revealed a very slight peak in both IAS and Fuel Flow at the > 6750rpm point at basically all altitudes. > I think what this is suggesting is that increasing rpm beyond 6750 is onl= y > increasing wear and has no benefit given the current intake/exhaust > configuration. > > With the current Prop Fine Pitch Limit, on initial WOT at Takeoff the > engine consistently hits 6900rpm within ~6 seconds and 7000rpm by liftoff > at 70 KIAS. > It then generally builds to 7400rpm (With no pitch adjustment - We > presently don't have a Constant Speed Controller) before throttling back = as > we turn downwind. > > I think this would suggest we ought adjust the props fine limit marginall= y > so that takeoff WOT yields approx 6700rpm and keeping the rpm as close to > 6750rpm as > possible when seeking maximum power by manual prop pitch adjustment. > A Constant Speed Controller would be nice! > > I=E2=80=99m now thinking we have enough data to tune the Mixture Correcti= on Table > of the EC2=E2=80=99s computers for climbing at 6750rpm and as Bill sugges= ted > cruising at 6000rpm. > > Next step in tuning in the Glasair Super IIRG will be playing with the > cowl flaps and cooling drag. Presently the flaps are wide open and draggy= . > I=E2=80=99m in the process of completing a little box of 5 differential p= ressure > transducers (MPX10DP=E2=80=99s) mounted under the cowl. > I worked out that they interface quite nicely without any other circuitry > with the Dynon Skyview's surplus EGT inputs via a new Polynomial in the > sensor config settings. > So hoping in the next few weeks to ascertain how the inlets, diffusers an= d > outlets are functioning or not. > What I like about the MPX10 interface with the Skyview EFIS is the > simplicity of displaying the pressure data inflight while its all logged > along with engine and flight data > for analysis on the ground. > > I=E2=80=99ve got 7 more hours of Phase #1 testing. > So far both aircraft and engine are really great. > > My friend and test pilot Dawie also demonstrated at the end of todays > flight - a Lazy Eight, a Roll and Wingover. > I felt sick for the next 3 hours. I don't think aerobatics will be in my > future. > > Thanks for all the help you guys. > > Steve Izett > Perth Western Australia > Glasair Super IIRG Renesis 4 port RD1C EC2 EM3 > > > > > > > > > > On 7 Aug 2020, at 2:25 pm, William Jepson wrjjrs@gmail.com < > flyrotary@lancaironline.net> wrote: > > > > Stephen, > > The answer to one of your questions is easy. A fast cruise RPM should b= e > 6000. Mazda did many instrumented runs and found that 6000 rpm was a swee= t > spot where the dynamics balanced perfectly. At 6000 there is almost no lo= ad > on the bearings. The rotary would run at that RPM indefinitely. If you ha= ve > more power at higher speeds you can use that for maximum speed. Those RPM= s > are eshaft RPMs not propeller. > > Bill > > > > On Thu, Aug 6, 2020 at 4:15 PM Stephen Izett stephen.izett@gmail.com < > flyrotary@lancaironline.net> wrote: > > Hi Guys > > > > Thanks for all the feedback. > > I think I didn=E2=80=99t explain my objective clearly enough. > > > > Some questions: > > 1. Given I have variable pitch, what combination of MAP and RPM should = I > climb or cruise at? With fixed pitch I dont suppose you think in these > terms. > > So should I be Climbings at WOT & 7000rpm OR WOT & 6300rpm Best Power > Mixture. > > > > I think Lynn best understood my intention of trying to use the flight a= s > a dyne - I didn=E2=80=99t realise the complexity of the relationship of m= ixture and > timing at various settings, thanks Lynn. > > I thought by keeping WOT and mixture constant I might ascertain a > maximum efficiency combination for MAP/RPM. > > > > I=E2=80=99d like a combination for max power. I=E2=80=99m thinking iden= tified by higher > fuel burn and IAS for the climb, and > > a max efficiency/ecconomy combination for cruise identified by best > miles per gallon. > > > > I thought our Renesis with our modified OEM (shortened) manifold but no > variable intake valves etc. would have a distinctive peak at ~6400-6600rp= m. > > > > 2. I=E2=80=99m finding tuning the EC2 (objective being EC provides cons= tant > mixture across the flight envelope) is dependant on the combination I > choose to tune it at. > > Eg. Tune EC2 MCT for one MAP/RPM combination, say a cruise of 18=E2=80= =9D AND > 5000 rpm, then the EC will not be able to provide a constant mixture if I > then choose 18=E2=80=9D at 6000rpm. > > My EC2 has Tracy=E2=80=99s 8 table setup but fueling requirements given= the > extra permutations provided by the variable pitch prop (climbing that hil= l > - which gear should I use - 3rd 4th or 5th??) > > appears to stretch its inherent capabilities. So I want a plan for what > MAP/RPM I will use and then adjust/tune the EC MCT for that combination. > > > > Thanks again guys. > > > > Steve Izett > > > > > > all is nice if you fly that combination. If I then choose ab > > > > > On 7 Aug 2020, at 6:16 am, lehanover lehanover@aol.com < > flyrotary@lancaironline.net> wrote: > > > > > > Your thinking is correct. Control full throttle RPM with load. Then > experiment always at that particular RPM until you have whatever data poi= nt > you were after. Everything affects everything so it may be that (for > example) advancing ignition timing at one RPM adds power but at another R= PM > reduces power. A rich mixture at one RPM may increase power but reduce > power at another RPM. To recover even similar data on consecutive days is > difficult. The SAE has some charts that produce a multiplier to account f= or > density temperature and so on. Required to compare results day to day. It > takes a long time to collect good data.......... > > > > > > Lynn E. Hanover > > > > > > > > > > > > > https://search.aol.com/aol/image?p=3Ddyno+sheets+for+stock+rx-7+engines&s= _it=3Dimg-ans&v_t=3Dloki-keyword&fr=3Dloki-keyword&imgurl=3Dhttp%3A%2F%2Fww= w.rx7club.com%2Fattachments%2Ftime-slips-dyno-128%2F346326d1243952257-anyon= e-have-stock-turbo-ii-dyno-graph-stock-s4-t2.jpg#id=3D19&iurl=3Dhttp%3A%2F%= 2Fwww.rx7club.com%2Fattachments%2Ftime-slips-dyno-128%2F346326d1243952257-a= nyone-have-stock-turbo-ii-dyno-graph-stock-s4-t2.jpg&action=3Dclick > > > > > > -- > > Homepage: http://www.flyrotary.com/ > > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > --000000000000fb973a05ac4a819a Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
That's curious. Are you saying that fuel flow *decreased*= as rpm *increased* above 6750 rpm? And airspeed decreased, as well? The on= ly way fuel flow should decrease as rpm increases is if the load on the eng= ine is going down.

Is the= prop running out of pitch (or ability to absorb the HP) as you get faster?= Is the airframe hitting a drag wall due to cooling drag (still shouldn'= ;t show a reduction in fuel flow; it just wouldn't go any faster)?

What actual speeds are you ac= hieving when this is happening?

Refresh my memory; who's prop (what blades) is it?=C2=A0

Do engine temps go up as you g= et above 6750 rpm?

Think = about the 'airplane as dyno' thing: If rpm continues to go up, and = the drag (our substitute for torque on the engine brake in a real dyno) sta= ys the same or increases, then power *must* be increasing, and so must fuel= flow. Simple math; (torque*rpm)/5252. So, was the plane going downhill, or= was the prop unable to absorb the additional power and decoupling, unloadi= ng the engine?
=
Charlie

On Fri, Aug 7, 2020 at 9:01 AM Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
Hi Guys.

Today we did some engine data analysis at 9500, 7500, 6000 and 4500 feet ag= l.
WOT with constant best power mixture of 0.9 Lambda.
We looked at Fuel Flow and IAS at 5500,5750,6000,6250,6500,6750 & 7000r= pm.
The data revealed a very slight peak in both IAS and Fuel Flow at the 6750r= pm point at basically all altitudes.
I think what this is suggesting is that increasing rpm beyond 6750 is only = increasing wear and has no benefit given the current intake/exhaust configu= ration.

With the current Prop Fine Pitch Limit, on initial WOT at Takeoff the engin= e consistently hits 6900rpm within ~6 seconds and 7000rpm by liftoff at 70 = KIAS.
It then generally builds to 7400rpm (With no pitch adjustment - We presentl= y don't have a Constant Speed Controller) before throttling back as we = turn downwind.

I think this would suggest we ought adjust the props fine limit marginally = so that takeoff WOT yields approx 6700rpm and keeping the rpm as close to 6= 750rpm as
possible when seeking maximum power by manual prop pitch adjustment.
A Constant Speed Controller would be nice!

I=E2=80=99m now thinking we have enough data to tune the Mixture Correction= Table of the EC2=E2=80=99s computers for climbing at 6750rpm and as Bill s= uggested cruising at 6000rpm.

Next step in tuning in the Glasair Super IIRG will be playing with the cowl= flaps and cooling drag. Presently the flaps are wide open and draggy.
I=E2=80=99m in the process of completing a little box of 5 differential pre= ssure transducers (MPX10DP=E2=80=99s) mounted under the cowl.
I worked out that they interface quite nicely without any other circuitry w= ith the Dynon Skyview's surplus EGT inputs via a new Polynomial in the = sensor config settings.
So hoping in the next few weeks to ascertain how the inlets, diffusers and = outlets are functioning or not.
What I like about the MPX10 interface with the Skyview EFIS is the simplici= ty of displaying the pressure data inflight while its all logged along with= engine and flight data
for analysis on the ground.

I=E2=80=99ve got 7 more hours of Phase #1 testing.
So far both aircraft and engine are really great.

My friend and test pilot Dawie also demonstrated at the end of todays fligh= t - a Lazy Eight, a Roll and Wingover.
I felt sick for the next 3 hours. I don't think aerobatics will be in m= y future.

Thanks for all the help you guys.

Steve Izett
Perth Western Australia
Glasair Super IIRG Renesis 4 port RD1C EC2 EM3








> On 7 Aug 2020, at 2:25 pm, William Jepson wrjjrs@gmail.com <flyrotary@lancaironline.net>= ; wrote:
>
> Stephen,
> The answer to one of your questions is easy. A fast cruise RPM should = be 6000. Mazda did many instrumented runs and found that 6000 rpm was a swe= et spot where the dynamics balanced perfectly. At 6000 there is almost no l= oad on the bearings. The rotary would run at that RPM indefinitely. If you = have more power at higher speeds you can use that for maximum speed. Those = RPMs are eshaft RPMs not propeller.
> Bill
>
> On Thu, Aug 6, 2020 at 4:15 PM Stephen Izett stephen.izett@gmail.com <flyrotary@lancair= online.net> wrote:
> Hi Guys
>
> Thanks for all the feedback.
> I think I didn=E2=80=99t explain my objective clearly enough.
>
> Some questions:
> 1. Given I have variable pitch, what combination of MAP and RPM should= I climb or cruise at? With fixed pitch I dont suppose you think in these t= erms.
> So should I be Climbings at WOT & 7000rpm OR WOT & 6300rpm Bes= t Power Mixture.
>
> I think Lynn best understood my intention of trying to use the flight = as a dyne - I didn=E2=80=99t realise the complexity of the relationship of = mixture and timing at various settings, thanks Lynn.
> I thought by keeping WOT and mixture constant I might ascertain a maxi= mum efficiency combination for MAP/RPM.
>
> I=E2=80=99d like a combination for max power. I=E2=80=99m thinking ide= ntified by higher fuel burn and IAS for the climb, and
> a max efficiency/ecconomy combination for cruise identified by best mi= les per gallon.
>
> I thought our Renesis with our modified OEM (shortened) manifold but n= o variable intake valves etc. would have a distinctive peak at ~6400-6600rp= m.
>
> 2. I=E2=80=99m finding tuning the EC2 (objective being EC provides con= stant mixture across the flight envelope) is dependant on the combination I= choose to tune it at.
> Eg. Tune EC2 MCT for one MAP/RPM combination, say a cruise of 18=E2=80= =9D AND 5000 rpm, then the EC will not be able to provide a constant mixtur= e if I then choose 18=E2=80=9D at 6000rpm.
> My EC2 has Tracy=E2=80=99s 8 table setup but fueling requirements give= n the extra permutations provided by the variable pitch prop (climbing that= hill - which gear should I use - 3rd 4th or 5th??)
> appears to stretch its inherent capabilities. So I want a plan for wha= t MAP/RPM I will use and then adjust/tune the EC MCT for that combination.<= br> >
> Thanks again guys.
>
> Steve Izett
>
>
>=C2=A0 all is nice if you fly that combination. If I then choose ab
>
> > On 7 Aug 2020, at 6:16 am, lehanover lehanover@aol.com <flyrotary@lancaironline.net&= gt; wrote:
> >
> > Your thinking is correct. Control full throttle RPM with load. Th= en experiment always at that particular RPM until you have whatever data po= int you were after. Everything affects everything so it may be that (for ex= ample) advancing ignition timing at one RPM adds power but at another RPM r= educes power. A rich mixture at one RPM may increase power but reduce power= at another RPM. To recover even similar data on consecutive days is diffic= ult. The SAE has some charts that produce a multiplier to account for densi= ty temperature and so on. Required to compare results day to day. It takes = a long time to collect good data..........
> >
> > Lynn E. Hanover=C2=A0
> >
> >
> >
> > h= ttps://search.aol.com/aol/image?p=3Ddyno+sheets+for+stock+rx-7+engines&= s_it=3Dimg-ans&v_t=3Dloki-keyword&fr=3Dloki-keyword&imgurl=3Dht= tp%3A%2F%2Fwww.rx7club.com%2Fattachments%2Ftime-slips-dyno-128%2F346326d124= 3952257-anyone-have-stock-turbo-ii-dyno-graph-stock-s4-t2.jpg#id=3D19&i= url=3Dhttp%3A%2F%2Fwww.rx7club.com%2Fattachments%2Ftime-slips-dyno-128%2F34= 6326d1243952257-anyone-have-stock-turbo-ii-dyno-graph-stock-s4-t2.jpg&a= ction=3Dclick
>
>
> --
> Homepage:=C2=A0 http://www.flyrotary.com/
> Archive and UnSub:=C2=A0 =C2=A0http:/= /mail.lancaironline.net:81/lists/flyrotary/List.html


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