X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.23.0 (ClamAV engine v0.103.0) From: "Charlie England ceengland7@gmail.com" Received: from mail-io1-f47.google.com ([209.85.166.47] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 966089 for flyrotary@lancaironline.net; Fri, 20 Nov 2020 10:03:45 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.166.47; envelope-from=ceengland7@gmail.com Received: by mail-io1-f47.google.com with SMTP id o8so1755937ioh.0 for ; Fri, 20 Nov 2020 07:03:45 -0800 (PST) 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=OVzBDu7pSTFbCKz02TE7kPEbf/WkJWm305ClMPb1zno=; b=hQHef4qmXE4p8Vx2aU6N13Iw87ixUsFCVLJpS++U5N0kc1zX1FftUiIFcVITfK5kjH RbrdpToeyTeqJss0O0gU+YYZ6+MUqkKhhgyw9mwTQWKVwGmH210sKlIyb5hC514JdUxy BHLIjbWggFOvIKpoBkwa6Q82HUuq5aFoli++LteaKnzqg4yw3Rx86tZ7Qpz30aB6EfUB OSwvyuK/vEsR057niDLeZ2W0iTkQe+nxTivVSoqcH/vSrKQkVf49dXKo3eIBair1MEKq Yisil1pQ8cjk7w05rh3HtNeyGw0QZymk1pAB+FPL1NWD1MlRYQWuQy3WxYYd/E6wkH1P VaoQ== 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=OVzBDu7pSTFbCKz02TE7kPEbf/WkJWm305ClMPb1zno=; b=M/bLwPMvSSt25kAeLrcD0OY/VfmCplxCLUVZ0WDHKtDnQWGIFpQaFh8++xZS3i6E+6 YY325NMtsH9XhNWaxJ9NpSZaHImbJdeHA8yH1OFPrePtxZOgMWIH6povqCNCeKoQhFPQ Mpu//FnzxW967V3hGUekdZgUcGPvIiRBfZ4UjXjMybHr4w+lyoweF3cQO/RZ+HCOCTB1 sa07fFt1KuKMcWuS4uYA6keWyH/aFrW0gKrmh436R/XHmMIcBrQEwvAd+wtPEp4BWQ8U 57O5WFYPQqMQAcfnZ8R2xD9kcLgwsliE+T9B2/pbbQlefn41VtnEcTxTv2OtRAqGseRM njJw== X-Gm-Message-State: AOAM533o6fkgzVi74e1j6cSfbVCbHGombmhEEk37BBcDw09jxtzZWWQW eTeM4ttl04dj3qQIt/LsjmW5msCyerQ1Cn6TFH3PujiK X-Google-Smtp-Source: ABdhPJyFcx/0STBuSK3tGlZ3KNttNhJQZyS4n49/1+GTTHgcqveOreMsndr3lNAF/N/6IXHjawkzMzhuzPb2vada3UA= X-Received: by 2002:a6b:dc0f:: with SMTP id s15mr25547697ioc.180.1605884607363; Fri, 20 Nov 2020 07:03:27 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: Date: Fri, 20 Nov 2020 08:58:41 -0600 Message-ID: Subject: Re: [FlyRotary] Re: Cooling Mods to Glasair To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="000000000000928df305b48b25cc" --000000000000928df305b48b25cc Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable When I was preparing to build my wedge diffuser, Tracy looked at my mold & thought it looked a little too thick at the back (IIRC, it varied from about 4.5" at the front to a bit under 1/2" at the back). When I tested it using a leaf blower & a piece of thread on a stick to visualize exit flow, virtually all the air was coming out the back 1/4 of the radiator's area. I ended up with the back edge of the diffuser almost touching the core, to get even flow across the full face of the core. It's not a straight wedge; it's almost the inverse of the curve you see in a K&W Streamline Diffuser. I'm nowhere near flying, so I can't tell how effective it will be for actual cooling, but at least exit air flow is fairly even across the face of the core. Cowl flaps: I remember Bill Eslick having issues with being able to close his cowl flap due to air pressure holding it open, and I think he ended up using the flap actuator linear actuator used for RV's wing flaps. I later saw an idea from another friend's Lyc powered RV8. He put the pivot point for his cowl flap near the middle of the flap, so it acts more like a throttle butterfly. The leading edge of the flap is rounded like a teardrop, and the mating point on the cowl matches it, to smooth flow. Just a thought... Charlie Virus-free. www.avast.com <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> On Fri, Nov 20, 2020 at 8:04 AM Stephen Izett stephen.izett@gmail.com < flyrotary@lancaironline.net> wrote: > Hi Matt > > I=E2=80=99m finding the wedge wall needs to be more curved inwards toward= s the > back to reduce the area and air flow in that region. > Pretty much as London describes in his investigation back in 1968. > My copy is too big to send over this channel. > > I=E2=80=99m wondering what people have found as far as the delta T across= their > Water Coolers? > I=E2=80=99m seeing between 8-10F between in to out coolant temps with OAT= temps of > around 79F. > > Cheers > > Steve > > > > > > On 20 Nov 2020, at 9:46 pm, Matt Boiteau mattboiteau@gmail.com < > flyrotary@lancaironline.net> wrote: > > > > Ah that's so great to hear that you are at that testing phase. > > I too believe the wedge shape isn't all it's supposed to be. > > What reshape did you end up with ? > > > > - Matt Boiteau > > > > > > On Fri, Nov 20, 2020 at 5:28 AM Stephen Izett stephen.izett@gmail.com < > flyrotary@lancaironline.net> wrote: > > Hi Guys > > > > I thought I should provide an update. > > > > Having installed 5 differential pressure transducers and interfaced the= m > via spare Dynon EGT inputs, Ive been collecting some H2O diffuser pressur= e > data. > > > > First tests took pressure readings at 5 points (4 taps, 4 inches in fro= m > the four corners and one in the middle) referenced to the ships Static > system. > > Today I changed those taps to reference the pressure directly across th= e > core at these same locations. > > > > This has revealed the importance of measuring the pressure across the > radiator as the pressures behind the radiator is not at all equal. > > > > The data has revealed that our wedge diffuser was not equally > distributing the air pressure across the radiator face very well at all. > > Far more air was going through the back area as others have reported in > the past. > > > > So we will reshape the diffuser wall, making it harder for the air to > get to the back and retest. > > > > We have also increased the Oil inlet area from ~9in2 to ~ 14in2 and thi= s > has improved the oil temps. > > On a flight today OAT of 79F on climb out Oil and H2O temps peaked at > 210F. > > > > I=E2=80=99m very happy with the changes and expect to get further impro= vements, > and will shortly turn our attension to mechanising the cowl flaps to get > temps up and cooling drag down in the cooler air. > > > > Cheers > > > > Steve Izett > > Glasair Super IIRG Renesis 4 port RD1C, EC2, EM3 > > -- > > 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 > --000000000000928df305b48b25cc Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Whe= n I was preparing to build my wedge diffuser, Tracy looked at my mold &= thought it looked a little too thick at the back (IIRC, it varied from abo= ut 4.5" at the front to a bit under 1/2" at the back). When I tes= ted it using a leaf=C2=A0blower & a piece of thread on a stick to visua= lize exit flow, virtually all the air was coming out the back 1/4 of the ra= diator's area. I ended up with the back edge of the diffuser almost tou= ching the core, to get even flow across the full face of the core. It's= not a straight wedge; it's almost the inverse of the curve you see in = a K&W Streamline Diffuser. I'm nowhere near flying, so I can't = tell how effective it will be for actual cooling, but at least exit air flo= w is fairly even across the face of the core.

Cowl flaps: I remember Bill Eslick having issues with = being able to close his cowl flap due to air pressure holding it open, and = I think he ended up using the flap actuator linear actuator used for RV'= ;s wing flaps. I later saw an idea from another friend's Lyc powered RV= 8. He put the pivot point for his cowl flap near the middle of the flap, so= it acts more like a throttle butterfly. The leading edge of the flap is ro= unded like a teardrop, and the mating point on the cowl matches it, to smoo= th flow. Just a thought...

Charlie

3D"" Virus-free. www.avast.com

On Fri, Nov 20, 2020 at 8:04 AM Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
Hi Matt

I=E2=80=99m finding the wedge wall needs to be more curved inwards towards = the back to reduce the area and air flow in that region.
Pretty much as London describes in his investigation back in 1968.
My copy is too big to send over this channel.

I=E2=80=99m wondering what people have found as far as the delta T across t= heir Water Coolers?
I=E2=80=99m seeing between 8-10F between in to out coolant temps with OAT t= emps of around 79F.

Cheers

Steve




> On 20 Nov 2020, at 9:46 pm, Matt Boiteau mattboiteau@gmail.com <flyrotary@lancaironline.n= et> wrote:
>
> Ah that's so great to hear that you are at that testing phase.
> I too believe the wedge shape isn't all it's supposed to be. > What reshape did you end up with ?
>
> - Matt Boiteau
>
>
> On Fri, Nov 20, 2020 at 5:28 AM Stephen Izett stephen.izett@gmail.com <flyrotary@lancai= ronline.net> wrote:
> Hi Guys
>
> I thought I should provide=C2=A0 an update.
>
> Having installed 5 differential pressure transducers and interfaced th= em via spare Dynon EGT inputs, Ive been collecting some H2O diffuser pressu= re data.
>
> First tests took pressure readings at 5 points (4 taps, 4 inches in fr= om the four corners and one in the middle) referenced to the ships Static s= ystem.
> Today I changed those taps to reference the pressure directly across t= he core at these same locations.
>
> This has revealed the importance of measuring the pressure across the = radiator as the pressures behind the radiator is not at all equal.
>
> The data has revealed that our wedge diffuser was not equally distribu= ting the air pressure across the radiator face very well at all.
> Far more air was going through the back area as others have reported i= n the past.
>
> So we will reshape the diffuser wall, making it harder for the air to = get to the back and retest.
>
> We have also increased the Oil inlet area from ~9in2 to ~ 14in2 and th= is has improved the oil temps.
> On a flight today OAT of 79F on climb out Oil and H2O temps peaked at = 210F.
>
> I=E2=80=99m very happy with the changes and expect to get further impr= ovements, and will shortly turn our attension to mechanising the cowl flaps= to get temps up and cooling drag down in the cooler air.
>
> Cheers
>
> Steve Izett
> Glasair Super IIRG Renesis 4 port RD1C, EC2, EM3
> --
> 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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