X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=PbaBeRpd c=1 sm=1 tr=0 a=CNxroDhzFkgeuOxFWPoQVg==:117 a=x7bEGLp0ZPQA:10 a=oSMvVwY2MYMA:10 a=y4yBn9ojGxQA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=7g1VtSJxAAAA:8 a=YIhCDrhPDu534nMVgtoA:9 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=MzWmKsXxlKT-V-istU4A:9 a=LQNS05mfiEbMLx5l:21 a=Urk15JJjZg1Xo0ryW_k8:22 a=grOzbf7U_OpcSX4AJOnl:22 From: "David Leonard wdleonard@gmail.com" Received: from mail-oo1-f50.google.com ([209.85.161.50] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 610802 for flyrotary@lancaironline.net; Thu, 06 Aug 2020 11:31:46 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.50; envelope-from=wdleonard@gmail.com Received: by mail-oo1-f50.google.com with SMTP id k4so5240208ooa.9 for ; Thu, 06 Aug 2020 08:31:47 -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=WVktC/YjHqV8OCotLPU8eSwxPbf4WDlghmi4L/b4laA=; b=ZXLFO+Pr4d6MP+I9h06t6OcBa2IGnxOk2brBR+I0NMMvqQFh1JoI0EPvWOh4XiqwkY MPPudBl8GOatzVurn3PmUFHIKuRv00As4pdMC3EAaaftn8wUlqrdJ1ZAFSPghGa5CZ6Y jfl8QWhjiXzxfhtf6I4yiQMGoXIVbG7BOtFmn4rK2PHXVVsJy510d77JVkM/5ImtUyj3 ds/vqG1LBSHA+cNHu6/TqvMJfykUnoxiKABnZC6p5zKWwbyC9yPxKEYj4iyENWXqIXxO vUJnjRfAvWvF9oDCNexWQD93GBgyj6XJLiDghfU8JzauPZlZECGVGJdrZTQJ0ot4qs8n KWEg== 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=WVktC/YjHqV8OCotLPU8eSwxPbf4WDlghmi4L/b4laA=; b=CPAjfrv1AzItnqsUP8wB/baAIhizwpIq91PusQrmDWu/ttAps/agF5c/e8chzGPiSG Gy1WmtjDg0s+g4BuknY8NPHndmcIULFAi7mw7Wq4ml5j5HltKFY6j8uACSVQ+Ucuj6PS YCsgSupQJngFHeaGd6QecKiCmk+dlWBXu08BBcoInag92EeCKT4d3s5+X3IRxnWsrR3p XSqKLMe2Aq4+OgyowZyj40D+sOGRhCNncOOpCi9h6edaRQlG76yUFYpheSOals3phgoK gJAsdlOKu44GbWFBpXTCPD8Qi+vSi/iPZmdmz2kxYeBk8KHZ6Ddef7r0EMKF+uJVaU1A vFww== X-Gm-Message-State: AOAM531RHp4S/EuSHCOhUotaYfi5sx7KHIagSvpiL3RaWXXFaGb3ohZW 8b95yzQC9nlt+AL8MS+KLZ2/oTpdAgrdVEm+SuwxJQ== X-Google-Smtp-Source: ABdhPJwe7ynrnTQ8VK85wVJkEhXpN2co1qWjsZVX9ZUhAD1POXj28+Q0y1DCmb5dsseq4hngkuVEDp2ZBxCMukQhNSk= X-Received: by 2002:a4a:924b:: with SMTP id g11mr8395973ooh.9.1596727889274; Thu, 06 Aug 2020 08:31:29 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: Date: Thu, 6 Aug 2020 08:31:17 -0700 Message-ID: Subject: Re: [FlyRotary] Testing best rpm power setting To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="000000000000a4acdf05ac372e33" --000000000000a4acdf05ac372e33 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Steve, The torque curve for the rotary is fairly flat up into the 8000+ RPM range. So in general, HP will continue to go up with RPM until destruction of the bearings around 1100 is a number I have seen floated around for stock rotors. The prop will start becoming very inefficient as the tips go supersonic. That means, you calculate your RPM for supersonic tip speed, and that will be best power/redline limit. Peak efficiency is a different story. Dave Leonard On Thu, Aug 6, 2020 at 7:59 AM Stephen Izett stephen.izett@gmail.com < flyrotary@lancaironline.net> wrote: > Hi guys > > I=E2=80=99m wanting to inflight test for the best RPM for peak power of o= ur 4 port > Renesis with variable pitch prop (No constant speed control at present). > On Takeoff at Full Fine we hit 6900 after a few seconds and then rpm > builds to 7400 by 500 feet and 110 KIAS > I=E2=80=99m wondering if we are well past the peak torque and would be be= tter off > at a lower rpm. > > Am I right in thinking the following would use the aircraft as a Dyno to > establish rpm for best power? > > 1. Set up level flight (auto pilot) > 2. Maintain WOT and constant mixture (best power - say 0.9 Lambda - 13.2 > AFR) via Wideband O2 > 3. Vary RPM in 200rpm increments for 2 minutes each setting between 5600 > and 7200 by adjusting prop pitch > 4. Note Fuel Flow and IAS (Logged on Dynon Skyview) > > I=E2=80=99m thinking this would give me an indication of best RPM for hig= hest > power. > Our Inlet is just under 19=E2=80=9D long, measured from the side face of = the > engine. > So I=E2=80=99m thinking peak torque may be around 6400 rpm. > > Your insight would be appreciated. > Thanks > > Steve Izett > Renesis 4 port RD1C (2.85:1) Inflight Adjustable Prop > > > > > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > --000000000000a4acdf05ac372e33 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Steve,

The torque curve f= or the rotary is fairly flat up into the 8000+ RPM range.=C2=A0 So in gener= al, HP will continue to go up with RPM until destruction of the bearings ar= ound 1100 is a number I have seen floated around for stock rotors.=C2=A0 Th= e prop will start becoming very inefficient as the tips go supersonic.

That means, you calculate your RPM for supersonic tip = speed, and that will be best power/redline limit.

= Peak efficiency is a different story.

Dave Leonard=

On Thu, Aug 6, 2020 at 7:59 AM Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
Hi guys

I=E2=80=99m wanting to inflight test for the best RPM for peak power of our= 4 port Renesis with variable pitch prop (No constant speed control at pres= ent).
On Takeoff at Full Fine we hit 6900 after a few seconds and then rpm builds= to 7400 by 500 feet and 110 KIAS
I=E2=80=99m wondering if we are well past the peak torque and would be bett= er off at a lower rpm.

Am I right in thinking the following would use the aircraft as a Dyno to es= tablish rpm for best power?

1. Set up level flight (auto pilot)
2. Maintain WOT and constant mixture (best power - say 0.9 Lambda - 13.2 AF= R) via Wideband O2
3. Vary RPM in 200rpm increments for 2 minutes each setting between 5600 an= d 7200 by adjusting prop pitch
4. Note Fuel Flow and IAS (Logged on Dynon Skyview)

I=E2=80=99m thinking this would give me an indication of best RPM for highe= st power.
Our Inlet is just under 19=E2=80=9D long, measured from the side face of th= e engine.
So I=E2=80=99m thinking peak torque may be around=C2=A0 6400 rpm.

Your insight would be appreciated.
Thanks

Steve Izett
Renesis 4 port RD1C (2.85:1) Inflight Adjustable Prop






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