X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=PbaBeRpd c=1 sm=1 tr=0 a=dFnnagVfVWeg+/bq/M6kfQ==:117 a=y4yBn9ojGxQA:10 a=aOWVIxkx-zkA:10 a=3oc9M9_CAAAA:8 a=Ia-xEzejAAAA:8 a=pGLkceISAAAA:8 a=0qqORytXAAAA:8 a=7g1VtSJxAAAA:8 a=A5MILvt7eGUNrX9ooSgA:9 a=2yjAEVCR_1eH5hVk:21 a=1-n76MeiSUjQEzNh:21 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=d7OJ2h0JwCJzZ7hYkB0A:9 a=ZhBMuo0BOJAQCQB2:21 a=T2Juc6bgQtIcKLJU:21 a=7NJFsOLxrYvGmgzZ:21 a=Urk15JJjZg1Xo0ryW_k8:22 a=Nj1bhqyGrdl6Az3_ctNx:22 a=grOzbf7U_OpcSX4AJOnl:22 From: "Andrew Martin andrew@martinag.com.au" Received: from mail-wr1-f43.google.com ([209.85.221.43] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 617315 for flyrotary@lancaironline.net; Fri, 07 Aug 2020 20:27:10 -0400 Received-SPF: none receiver=logan.com; client-ip=209.85.221.43; envelope-from=andrew@martinag.com.au Received: by mail-wr1-f43.google.com with SMTP id f12so3097034wru.13 for ; Fri, 07 Aug 2020 17:27:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=martinag-com-au.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=ndFCQmKj/fU88M8DjLmnvHdvzldHKPnmI7zdvHHDDgU=; b=0vbl98QAKbRDEP15qxbzJcHiQKpHv8W6JBa9qVD1iKNbh9CaRsNZxCpR92V9QwwpI2 fbX1VcmhAZlaY7anC2Hgi/mCGOt+kJk7vZK9XuLzKu0B4KZG2nRngyO0dCuX1iwMzqzg 0pMX7Rh2eWwsWpfbfKQsWNkdG+3b3rwZYgKASYh6ViaHAj34OsuNoffF23LxuB0yadi8 fXR72WrLd1ovyHM2ohJopWmSd2hkgjJ0ztiy27xDJW/6ZVu8Fjl1xUDRrMQjNhYjE4lO zKKkBZG7A1fzma+whhN+RO2UQY+2r/PzYD93oipiXTL3aO8jDOpoq/K+Nl+mwkH2Hg7N Clow== 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=ndFCQmKj/fU88M8DjLmnvHdvzldHKPnmI7zdvHHDDgU=; b=ORNfWN6TnjoffwPo+FQQin/mDMx1bzxStvK2kMC1wxwyCjLFEmWrAZBYt6dOruVOQL Y1q7R1r9gxjJvzl71sg3+RBQoRcuCm+TsghgOGCeGZvddvYTA5X0Q5Jz1PamXXj3B9Tw 4RsKTBRSsAf9jkYCz5ecQHs2RZ7nAqUdQjmu2b2kBeNvDVYHvCCKDFlzOYqP8aMl0p0v 6CTyc0O9cZTuB7RQxR4/J9Oj94zFscQvxSSufsnCV1i+rtI8cFZOcommNn2GxB9mD3XP QAiJx3JLdlOWDK45AeOSWuuTmlZXaqWVRq3k80s+o/AIcCtRntvh+Uza5aKLhy+JIzkW lM+Q== X-Gm-Message-State: AOAM532sjqM3qI6DQR1xyTE5bCs5z4kNc+LRDpF9M1ZoKqvUaqMYnJFY Kj69kPyqEE/dPh233y0PkYJlhnxWtZAcWhyO9BBkwvM= X-Google-Smtp-Source: ABdhPJxlBx8OHKRbpxrVJznwJcl1pzewBH+FECq+lPuOc/o2DwaIMe7gG/66wUNDrOfydpXKlunIYGdmozKnd/A4HQQ= X-Received: by 2002:a5d:43ca:: with SMTP id v10mr13978655wrr.299.1596846412733; Fri, 07 Aug 2020 17:26:52 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: Date: Sat, 8 Aug 2020 08:26:40 +0800 Message-ID: Subject: Re: [FlyRotary] Re: Dyno Sheet To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="00000000000031358105ac52c724" --00000000000031358105ac52c724 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Lynn, I read it that Steve went to 9500=E2=80=99 agl. Max rpm was 7000. So = all should be good. Andrew On Sat, 8 Aug 2020 at 8:09 am, lehanover lehanover@aol.com < flyrotary@lancaironline.net> wrote: > The impossible is possible................ > > Along the way to tuning success you will find that a specific combination > of facts may appear and disappear within a few RPM. Such as induction tu= be > length VS exhaust system harmonics/back pressure. Every RPM would suggest > that a specific tuned intake length would be ideal. See the Mazda winning= 4 > rotor and its adjustable length intake runners. Exhaust back pressure ma= y > be high at one RPM and nonexistent at another. The whole reason for > disconnecting the intake and exhaust in the Renesis among other things i= s > to get the tuning down to some form of normal (Meet California UHC). Havi= ng > no overlap is a giant step in that direction. The poor exhaust shapes hel= p > pollute the incoming charge a bit so as to reduce combustion temps and pu= ll > back Oxides of Nitrogen. I have seen movies of fuel air flowing backwards > in an intake runner. When you record what appears to be faulty data do > not discard it and then see it again the next day. When you mak= e > a change....make it a big one so you can see which way that one took you. > Never make more than one change. Use the SAE tables to take all of the > data down to sea level. Before you compare two data sets. It is a steep > learning curve......but it will come to you. I had a fabulous Stuska dyn= o > in my shop for years. > and a flow bench. I never did learn all I should have. > > Fixed pitch props (In effect) reduce pitch as air speed through the disc > increases. The suggestion that you turned up 9,500 RPM gives me chills. > What would the tip speeds be then? > > You can get above 10,000 RPM with 13-B rotors but they must be very light > and you must look inside after every race because the tend to crack when > that light. Note that the Renesis rear main bearing is two different > diameters to allow for that standing sign wave that forms in the crank. > Nobody uses Fram filters or lets friends turn over 8,000 RPM > Lynn E. Hanover > > In a message dated 8/7/2020 6:48:47 PM Eastern Standard Time, > flyrotary@lancaironline.net writes: > > Hi Charlie and all > > On the four runs - Speeds were: > 147 KIAS 21.6=E2=80=9D @ 9500 WOT > 136 KIAS 18.2=E2=80=9D @ 7500 (Not WOT) > 160 KIAS 24.8=E2=80=9D @ 6000 WOT > 165 KIAS 26.2=E2=80=9D @ 4500 WOT > > Prop hub is Airmaster 3 blade electric with Aerotek Blades > > On looking over the 4500 ft run: > As RPM steps up from 5500-7250 (in 250rpm inc) over 9 mins (OAT 49) > Temps gradually build from 172/154 to 198/171 (Oil/Water) > Fuel Flow goes from 14.5 peaking at 16.2 (6750) before ending at 15.8 > KIAS 160 peaking at 168 (7000) before ending at 166 > > We probably haven=E2=80=99t allowed enough time between changes for full = settling > of the numbers, but the trends seem consistent. > > Not sure I agree with your thoughts re engine rpm rising and drag constan= t > or rising =3D power must be increasing. > Torque x RPM =3D Power > RPM is increasing, but if torque is decreasing faster than rpm is rising, > power will be decreasing. > > What I was interested in discovering was the max power RPM. > My logic is, even if power is constant after 6750rpm (ie. rpm increasing > matches torque decreasing) there is no value in spinning her above that r= pm. > > What science could I do to discover this? > Rightly or wrongly, thats why I value this list, I was looking for the > peek in Fuel Flow AND IAS (I=E2=80=99m relying on the wideband O2 being a= ccurate > and keeping mixture constant) > Its not anything like dramatic, but I think I can maybe see evidence of > that best power (torque peek) RPM being somewhere around the 6750rpm > setting. > We had been spinning her up 600+RPM higher, perhaps for no advantage. > > On another note about the Intake manifold. We shortened the OEM unit to > lift peak torque from Mazda's 5000rpm documented curve, hoping for > something in the low 6000=E2=80=99s. > We also kept the VDI valve that opens at high RPM to provide Mazda=E2=80= =99s > Renesis intake shockwave charging, but presently I cant activate the valv= e > in flight. > And to be honest it seems to be producing a pleasing amount of hp at that > 6750rpm. > > On Takeoff with a mixture at a Lambda of 0.9 / 13.2 AFR she is burning 17 > Gal of our Premium Unleaded fuel using 1 Ounce / Gal of two stroke oil, > whatever hp that equates too. > > Is my logic OK here or am I just dreaming? > > Cheers > > Steve > > > > > > > > > > > > > > > > > > > > > > > > > > > > On 7 Aug 2020, at 10:34 pm, Charlie England ceengland7@gmail.com < > flyrotary@lancaironline.net> wrote: > > > > 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 i= s > 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 (stil= l > 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, an= d > 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 fee= t > 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 > only 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 > marginally 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 Correc= tion > Table of the EC2=E2=80=99s computers for climbing at 6750rpm and as Bill = suggested > 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= pressure > 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 Polynomia= l > 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 > 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 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 > sweet spot where the dynamics balanced perfectly. At 6000 there is almost > no load on the bearings. The rotary would run at that RPM indefinitely. I= f > 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@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 shoul= d > 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 > as a dyne - I didn=E2=80=99t realise the complexity of the relationship o= f mixture > 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 id= entified 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 > ~6400-6600rpm. > > > > > > 2. I=E2=80=99m finding tuning the EC2 (objective being EC provides co= nstant > 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 giv= en 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 > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > -- Regards Andrew Martin Martin Ag --00000000000031358105ac52c724 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Lynn, I read it that Steve went to 9500=E2=80=99 agl= . Max rpm was 7000. So all should be good.
And= rew

On Sat, 8 Aug 2020 at 8:09 am, lehanover lehanover@aol.com <flyrotary@lancaironline.net> wrote:
The impossible is possible................

Along the way to tuning success you will find that a specific= combination of facts may appear and disappear within a few RPM.=C2=A0 Such= as induction tube length VS exhaust system harmonics/back pressure. Every = RPM would suggest that a specific tuned intake length would be ideal. See t= he Mazda winning 4 rotor and its adjustable length intake runners.=C2=A0 Ex= haust back pressure may be high at one RPM and nonexistent at another. The = whole reason for disconnecting the intake and exhaust=C2=A0 in the Renesis = among other things is to get the tuning down to some form of normal (Meet C= alifornia UHC). Having no overlap is a giant step in that direction. The po= or exhaust shapes help pollute the incoming charge a bit so as to reduce co= mbustion temps and pull back Oxides of Nitrogen. I have seen movies of fuel= air flowing backwards in an intake runner.=C2=A0 =C2=A0 When you record wh= at appears to be faulty data do not discard it and then see it again the ne= xt day.=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0When you make a change....m= ake it a big one so you can see which way that one took you. Never make mor= e than one change.=C2=A0 Use the SAE tables to take all of the data down to= sea level. Before you compare two data sets.=C2=A0 =C2=A0It is a steep lea= rning curve......but it will come to you.=C2=A0 I had a fabulous Stuska dyn= o in my shop for years.
and a flow bench. I never did learn all I should have.

Fixed pitch props (In effect) reduce pitch as air speed throu= gh the disc increases.=C2=A0 The suggestion that you turned up 9,500 RPM gi= ves me chills. What would the tip speeds be then?

You can get above 10,000 RPM with 13-B rotors but they must b= e very light and you must look inside after every race because the tend to = crack when that light. Note that the Renesis rear main bearing is two diffe= rent diameters to allow for that standing sign wave that forms in the crank= .=C2=A0 Nobody uses Fram filters or lets friends turn over 8,000 RPM=
Lynn E. Hanover

In a message dated 8/7/2020 6:48:47 PM Eastern Standard Time, flyrotary@lancaironline= .net writes:

Hi Charlie and all

On the four runs - Speeds were:
147 KIAS 21.6=E2=80=9D @ 9500 WOT
136 KIAS 18.2=E2=80=9D @ 7500 (Not WOT)
160 KIAS 24.8=E2=80=9D @ 6000 WOT
165 KIAS 26.2=E2=80=9D @ 4500 WOT

Prop hub is Airmaster 3 blade electric with Aerotek Blades=

On looking over the 4500 ft run:
=C2=A0=C2=A0=C2=A0 As RPM steps up from 5500-7250 (in 250r= pm inc) over 9 mins (OAT 49)
=C2=A0=C2=A0=C2=A0 Temps gradually build from 172/154 to 1= 98/171 (Oil/Water)
=C2=A0=C2=A0=C2=A0 Fuel Flow goes from 14.5 peaking at 16.= 2 (6750) before ending at 15.8
=C2=A0=C2=A0=C2=A0 KIAS 160 peaking at 168 (7000) before e= nding at 166

We probably haven=E2=80=99t allowed enough time between ch= anges for full settling of the numbers, but the trends seem consistent.

Not sure I agree with your thoughts re engine rpm rising a= nd drag constant or rising =3D power must be increasing.
Torque x RPM =3D Power
RPM is increasing, but if torque is decreasing faster than= rpm is rising, power will be decreasing.

What I was interested in discovering was the max power RPM= .
My logic is, even if power is constant after 6750rpm (ie. = rpm increasing matches torque decreasing) there is no value in spinning her= above that rpm.

What science could I do to discover this?
Rightly or wrongly, thats why I value this list, I was loo= king for the peek in Fuel Flow AND IAS (I=E2=80=99m relying on the wideband= O2 being accurate and keeping mixture constant)
Its not anything like dramatic, but I think I can maybe se= e evidence of that best power (torque peek) RPM being somewhere around the = 6750rpm setting.
We had been spinning her up 600+RPM higher, perhaps for no= advantage.

On another note about the Intake manifold. We shortened th= e OEM unit to lift peak torque from Mazda's 5000rpm documented curve, h= oping for something in the low 6000=E2=80=99s.
We also kept the VDI valve that opens at high RPM to provi= de Mazda=E2=80=99s Renesis intake shockwave charging, but presently I cant = activate the valve in flight.
And to be honest it seems to be producing a pleasing amoun= t of hp at that 6750rpm.

On Takeoff with a mixture at a Lambda of 0.9 / 13.2 AFR sh= e is burning 17 Gal of our Premium Unleaded fuel using 1 Ounce / Gal of two= stroke oil, whatever hp that equates too.

Is my logic OK here or am I just dreaming?

Cheers

Steve





















=C2=A0=C2=A0

=C2=A0=C2=A0


> On 7 Aug 2020, at 10:34 pm, Charlie England ceengland7@gmail.com <flyrotary@lancaironline.= net> wrote:
>
> That's curious. Are you saying that fuel flow *de= creased* 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 absor= b the HP) as you get faster? Is the airframe hitting a drag wall due to coo= ling drag (still shouldn't show a reduction in fuel flow; it just would= n't go any faster)?
>
> What actual speeds are you achieving when this is hap= pening?
>
> 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 engi= ne 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 p= ower and decoupling, unloading the engine?
>
> Charlie
>
> On Fri, Aug 7, 2020 at 9:01 AM Stephen Izett stephen.izett@gmail.com <flyrotary@lancairo= nline.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 rp= m beyond 6750 is only increasing wear and has no benefit given the current = intake/exhaust configuration.
>
> With the current Prop Fine Pitch Limit, on initial WO= T at Takeoff the engine consistently hits 6900rpm within ~6 seconds and 700= 0rpm by liftoff at 70 KIAS.
> It then generally builds to 7400rpm (With no pitch ad= justment - 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 marginally so that takeoff WOT yields approx 6700rpm and keeping= the rpm as close to 6750rpm as
> possible when seeking maximum power by manual prop pi= tch 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 suggested 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 pressure transducers (MPX10DP=E2=80=99s) mounted under t= he 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 and outlets are functioning or not.
> What I like about the MPX10 interface with the Skyvie= w 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 t= he end of todays flight - a Lazy Eight, a Roll and Wingover.
> I felt sick for the next 3 hours. I don't think a= erobatics 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 f= ast cruise RPM should be 6000. Mazda did many instrumented runs and found t= hat 6000 rpm was a sweet spot where the dynamics balanced perfectly. At 600= 0 there is almost no load 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@lan= caironline.net> wrote:
> > Hi Guys
> >
> > Thanks for all the feedback.
> > I think I didn=E2=80=99t explain my objective cl= early 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 suppos= e 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 try= ing to use the flight as a dyne - I didn=E2=80=99t realise the complexity o= f the relationship of mixture and timing at various settings, thanks Lynn.<= /div>
> > 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 identified by higher fuel burn and IAS for the climb, a= nd
> > a max efficiency/ecconomy combination for cruise= identified by best miles per gallon.
> >
> > I thought our Renesis with our modified OEM (sho= rtened) manifold but no variable intake valves etc. would have a distinctiv= e peak at ~6400-6600rpm.
> >
> > 2. I=E2=80=99m finding tuning the EC2 (objective= being EC provides constant mixture across the flight envelope) is dependan= t on the combination I choose to tune it at.
> > Eg. Tune EC2 MCT for one MAP/RPM combination, sa= y a cruise of 18=E2=80=9D AND 5000 rpm, then the EC will not be able to pro= vide a constant mixture if I then choose 18=E2=80=9D at 6000rpm.
> > My EC2 has Tracy=E2=80=99s 8 table setup but fue= ling requirements given the extra permutations provided by the variable pit= ch prop (climbing that hill - which gear should I use - 3rd 4th or 5th??) <= /div>
> > 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
> >
> >
> >=C2=A0 all is nice if you fly that combination. I= f 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 thro= ttle RPM with load. Then experiment always at that particular RPM until you= have whatever data point you were after. Everything affects everything so = it may be that (for example) advancing ignition timing at one RPM adds powe= r but at another RPM reduces power. A rich mixture at one RPM may increase = power but reduce power at another RPM. To recover even similar data on cons= ecutive days is difficult. The SAE has some charts that produce a multiplie= r to account for density temperature and so on. Required to compare results= day to day. It takes a long time to collect good data..........
> > >
> > > Lynn E. Hanover
> > >
> > >
> > >
> >
> >
> > --
> > Homepage:=C2=A0 http://www.flyrotary.co= m/
>
>
> --
> Homepage:=C2=A0 http://www.flyrotary.com/


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Regards Andrew Martin Martin Ag
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