X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.23.0 (ClamAV engine v0.103.0) From: "David COOK hoursaway1@comcast.net" Received: from resqmta-ch2-01v.sys.comcast.net ([69.252.207.33] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 967540 for flyrotary@lancaironline.net; Fri, 20 Nov 2020 21:23:03 -0500 Received-SPF: pass receiver=logan.com; client-ip=69.252.207.33; envelope-from=hoursaway1@comcast.net Received: from resomta-ch2-15v.sys.comcast.net ([69.252.207.111]) by resqmta-ch2-01v.sys.comcast.net with ESMTP id gIUzkgApebwH3gIY2kANNG; Sat, 21 Nov 2020 02:22:46 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=comcast.net; s=20190202a; t=1605925366; bh=BHTmcxjV2MF2kMD95FyYC1dYPIZn6Jaf/zCPsfrT74I=; h=Received:Received:Date:From:To:Message-ID:Subject:MIME-Version: Content-Type; b=ml6SkwIioEaRZtw9KvdFGR3FK4hSL2y69Ck/KeySW6xS69GGpGXR0VyDC3PH9iDk1 m4YtwPrGQcP1c5fIudQhb6xPLyiI6W9SKbmRflb35+d4DUzqT56XnqcAc9VEzhrwFD i8M6gb2iriIzLM5nKseWzUvgAIOMXkG5GJnS9Tkyv+/AKPbWtYS3i+sSO4DBOmI1/2 s7ohnCh7zY6lVaGSzLOUgZdLxP6PWmCTMAUyK46hxJf3+2onuTkdnMlRFTkq5EvoKI xW/xWq79/uOmHLQrX+xAY5lh53hDxbYMirYuQuDr2Gv0t3kuV3oD6Wk2W5x3vXc2Lq uTQ/ecQ9hsjow== Received: from oxapp-ch2f-13o.email.comcast.net ([96.117.82.148]) by resomta-ch2-15v.sys.comcast.net with ESMTPS id gIY0kZSgfTaa1gIY2k7UiW; Sat, 21 Nov 2020 02:22:46 +0000 X-Xfinity-VAAS: gggruggvucftvghtrhhoucdtuddrgedujedrudeguddggeehucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuvehomhgtrghsthdqtfgvshhipdfqfgfvpdfpqffurfetoffkrfenuceurghilhhouhhtmecufedtudenucenucfjughrpeffhffvkfgjfhfugggtrfgkofhisegrtdersgertdejnecuhfhrohhmpeffrghvihguucevqffqmfcuoehhohhurhhsrgifrgihudestghomhgtrghsthdrnhgvtheqnecuggftrfgrthhtvghrnhepfeeflefhtddvkefhtdefgfefieffleetieehudeutdehhfeilefgteekuefggfegnecuffhomhgrihhnpehflhihrhhothgrrhihrdgtohhmpdhlrghntggrihhrohhnlhhinhgvrdhnvghtpdgrvhgrshhtrdgtohhmnecukfhppeeliedruddujedrkedvrddugeekpddutdegrdduvdelrdduleeirdduheejnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehhvghlohepohigrghpphdqtghhvdhfqddufehordgvmhgrihhlrdgtohhmtggrshhtrdhnvghtpdhinhgvthepleeirdduudejrdekvddrudegkedpmhgrihhlfhhrohhmpehhohhurhhsrgifrgihudestghomhgtrghsthdrnhgvthdprhgtphhtthhopehflhihrhhothgrrhihsehlrghntggrihhrohhnlhhinhgvrdhnvght X-Xfinity-VMeta: sc=0.00;st=legit Date: Fri, 20 Nov 2020 21:22:44 -0500 (EST) To: Rotary motors in aircraft Message-ID: <1015829032.16580.1605925364596@connect.xfinity.com> In-Reply-To: References: Subject: Re: [FlyRotary] Re: cooling modes MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_16579_1296511144.1605925364562" X-Priority: 3 Importance: Normal X-Mailer: Open-Xchange Mailer v7.10.3-Rev18 X-Originating-IP: ::ffff:104.129.196.157 X-Originating-Client: open-xchange-appsuite ------=_Part_16579_1296511144.1605925364562 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Wedge is kind of a poor term for what is needed, more of a bell mouth like = on a trumpet with the rad. being at the large end. DRC RV6A Rotary > On 11/20/2020 9:03 PM Charlie England ceengland7@gmail.com wrote: > =20 > =20 > Hi Bruce, >=20 > The driver for me was trying to remain within the constraints of mone= y, a stock cowl with minimum 'surgery', with nothing hanging out of the cow= l. Another driver was due to 'standing on the shoulders of giants'; Tracy C= rook does really light weight installations, and his calcs showed that at l= east in his RV4, he needed the weight of the heat exchangers to be up front= , to keep CG in the right place. My FWF weighs almost exactly the same as a= n O-320, so for now, I'll keep the wedge in place. Please be aware that my= setup may not survive to the 2nd flight. :-) >=20 > In retrospect, I might well have done the same as Steve mentioned, an= d at least try to tuck the rad into the space behind/below the engine and f= eed it with a duct up to the prop. >=20 > Charlie >=20 > On 11/20/2020 6:59 PM, Bruce Cosgrove bcosgrove@mac.com mailto:bcosgr= ove@mac.com wrote: >=20 > > > Hi Steve, Charlie, Matt, Roy and others > > I am in the process making up a cooling system for a Tango 2 a= nd was also planning to use the wedge shaped diffuser design, however the i= nformation that I have been reading from the homebuilt airplanes site discu= ssing alternate approaches with less drag and improved efficiency? has me r= e thinking my design towards a belly mounted radiator. The comments under = the heading Successful Auto Conversion Trials, Tribulations and Tips, I fo= und particularly interesting - in particular input from Russell and RJ6ejGU= Y who both have devised systems that are working well for them Belly radia= tors may not be everyones idea of how to proceed but I like the idea of rel= atively unimpeded air flow and freeing up space in the cowling. any feedba= ck would be much appreciated. > > =20 > > Bruce > >=20 > >=20 > > On 21 November 2020 at 10:00:57, Stephen Izett stephen.izett@gm= ail.com mailto:stephen.izett@gmail.com (flyrotary@lancaironline.net mailto:= flyrotary@lancaironline.net ) wrote: > >=20 > > > > > Nice work Charlie. > > >=20 > > > Steve > > >=20 > > > > On 21 Nov 2020, at 6:50 am, Charlie England ceengland7@= gmail.com mailto:ceengland7@gmail.com mailto:= flyrotary@lancaironline.net wrote: > > > > > > > > My (untested in combat) version for my radiator looks s= imilar, but because the inlet is offset, I had to use a turning vane to get= flow into the lower front of the core. The outside doesn't give a good ide= a on how 'tight' the inner surface is. I had to use expanding foam to fill = the inside, then re-shape, then glass over the foam. As I said, the back 1/= 4-1/3 of the diffuser tapers tightly to almost touch the core at the back. > > > > > > > > After observing both rotary and piston installations th= at work, I'm beginning to think that turning vanes may be the 'good enough'= vs fighting for perfection in diffuser shape. My oil cooler core has a muc= h more elaborate vane setup, driven by the very short duct length and even = greater offset to the bottom edge of the core. > > > > > > > > Charlie > > > > > > > > > > > > On 11/20/2020 4:22 PM, Stephen Izett stephen.izett@gmai= l.com mailto:stephen.izett@gmail.com wrote: > > > >> Hi Roy > > > >> > > > >> Here is a photo of our Mocal 44 row oil cooler with di= ffuser. A K&M Streamline into a wedge. > > > >> Not sure of the dimensions of hand. The Mocal web site= will have specs so you could get a rough idea of size. > > > >> I tested this one recently with a leaf blower approxim= ating 100 knot air flow and in that test it was very even. > > > >> > > > >> Having said that, I tested our water radiator wedge di= ffuser when I built it years ago and had it reasonably even > > > >> measuring pressures across the exit face, but now inst= rumenting it in flight its flow is vastly uneven. > > > >> > > > >> I have found that the flow is dependant not only on ge= tting the diffuser shape right according to the various papers (eg. K&W, Lo= ndon, Oblique Flow Diffusers - Streamline ) > > > >> But importantly the environment it ends up in. The pap= ers share data for ideal conditions with for example unobstructed exit air = paths. > > > >> My thoughts now are that this has a significant impact= on the performance and therefore the advantage of instrumenting in flight = and reshaping for actual conditions. > > > >> > > > >> The data I collected yesterday of our H2O diffuser rev= eals that the air flow in various points across the face are very different= . > > > >> Simplified, if I average the pressures at the five poi= nts I measured, then comparatively the back is up 20%, the centre up 25% an= d the front down 60% from that average figure. > > > >> I=E2=80=99m figuring a 20% difference is probably OK, = but my front to back/middle difference of ~80% down in the front top of tha= t radiator may hold significant room for improvement. > > > >> Further, my data suggests that as IAS rises those diff= erences are amplified. > > > >> So I am now targeting the modifications for our worst = case conditions of WOT sea level ~200hp and initial climb numbers of 115KIA= S. > > > >> > > > >> Cheers. > > > >> > > > >> Steve Izett > > > >> > > > >> > > > >> > > > >>> On 21 Nov 2020, at 3:37 am, ROY GLENN rglenn14@sbcglo= bal.net mailto:rglenn14@sbcglobal.net mailto:= flyrotary@lancaironline.net wrote: > > > >>> > > > >>> Could some ne post a photo of their wedge shape and d= imensions. > > > >>> Thanks Roy > > > >>> > > > >>> -- > > > >>> Homepage: http://www.flyrotary.com/ > > > >>> Archive and UnSub: http://mail.lancaironline.net:81/l= ists/flyrotary/List.html > > > >> > > > > > > > > > > > > > > > > > > > > This email has been checked for viruses by Avast antivi= rus software. > > > >http://www.avast.com > > > > > > > > > > > > -- > > > > Homepage: http://www.flyrotary.com/ > > > > Archive and UnSub: http://mail.lancaironline.net:81/lis= ts/flyrotary/List.html > > >=20 > > >=20 > > > -- > > > Homepage: http://www.flyrotary.com/ > > > Archive and UnSub: http://mail.lancaironline.net:81/lists= /flyrotary/List.html > > >=20 > > > > >=20 > > -- > > Homepage: http://www.flyrotary.com/ > > Archive and UnSub: http://mail.lancaironline.net:81/lists/fly= rotary/List.html > >=20 > > >=20 >=20 >=20 > --------------------------------------------- > [Avast logo] https://www.avast.com/antivirus =09 >=20 > This email has been checked for viruses by Avast antivirus software. > www.avast.com https://www.avast.com/antivirus >=20 ------=_Part_16579_1296511144.1605925364562 MIME-Version: 1.0 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable =20 =20
Wedge is kind o= f a poor term for what is needed, more of a bell mouth like on a trumpet wi= th the rad. being at the large end. DRC RV6A Rotary
=20
=20
On 11/20/2020 9:03 PM Charlie England ceengland7@gmail.com <flyrotar= y@lancaironline.net> wrote:
=20
 
=20
 
=20
Hi Bruce,=20

The driver for me was trying to remain within the constraints of mo= ney, a stock cowl with minimum 'surgery', with nothing hanging out of the c= owl. Another driver was due to 'standing on the shoulders of giants'; Tracy= Crook does really light weight installations, and his calcs showed that at= least in his RV4, he needed the weight of the heat exchangers to be up fro= nt, to keep CG in the right place. My FWF weighs almost exactly the same as= an O-320, so for now, I'll keep the  wedge in place. Please be aware = that my setup may not survive to the 2nd flight. :-)

In retrospect, I might well have done the same as Steve mentioned, = and at least try to tuck the rad into the space behind/below the engine and= feed it with a duct up to the prop.

Charlie

On 11/20/2020 6:59 PM, Bruce Cosgrove=20 bcosgrove@mac.com wrote:
=20
=20
Hi Steve, Charlie, Matt, Roy and others
=20
I am in the process making up a  cooling system for a Tango 2 and= was also planning to use the wedge shaped diffuser design, however the inf= ormation that I have been reading from the homebuilt airplanes site discuss= ing alternate approaches with less drag and improved efficiency? has me re = thinking my design towards a belly mounted radiator.  The comments und= er the heading  Successful Auto Conversion Trials, Tribulations and Tips, I found= particularly interesting - in particular input from Russell and RJ6ejGUY w= ho both have devised systems that are working well for them  Belly rad= iators may not be everyones idea of how to proceed but I like the idea of r= elatively unimpeded air flow and freeing up space in the cowling.  any= feedback would be much appreciated.
=20
 
=20
Bruce
=20
=20

On 21 November 2020 at 10:00:57, Stephen Izett = stephen.izett@gmail.com (flyrotary@lancaironline.net) wrote:

=20
=20
=20
Nice work Charlie.=20

Steve=20

> On 21 Nov 2020, at 6:50 am, Charlie England=20 ceengland7@gmail.com=20 <flyrotary@lancaironline.net> wrote:=20
>=20
> My (untested in combat) version for my radiator looks simil= ar, but because the inlet is offset, I had to use a turning vane to get flo= w into the lower front of the core. The outside doesn't give a good idea on= how 'tight' the inner surface is. I had to use expanding foam to fill the = inside, then re-shape, then glass over the foam. As I said, the back 1/4-1/= 3 of the diffuser tapers tightly to almost touch the core at the back.=20
>=20
> After observing both rotary and piston installations that w= ork, I'm beginning to think that turning vanes may be the 'good enough' vs = fighting for perfection in diffuser shape. My oil cooler core has a much mo= re elaborate vane setup, driven by the very short duct length and even grea= ter offset to the bottom edge of the core.=20
>=20
> Charlie=20
>=20
>=20
> On 11/20/2020 4:22 PM, Stephen Izett=20 stephen.izett@gmail.com wrote:=20
>> Hi Roy=20
>>=20
>> Here is a photo of our Mocal 44 row oil cooler with dif= fuser. A K&M Streamline into a wedge.=20
>> Not sure of the dimensions of hand. The Mocal web site = will have specs so you could get a rough idea of size.=20
>> I tested this one recently with a leaf blower approxima= ting 100 knot air flow and in that test it was very even.=20
>>=20
>> Having said that, I tested our water radiator wedge dif= fuser when I built it years ago and had it reasonably even=20
>> measuring pressures across the exit face, but now instr= umenting it in flight its flow is vastly uneven.=20
>>=20
>> I have found that the flow is dependant not only on get= ting the diffuser shape right according to the various papers (eg. K&W,= London, Oblique Flow Diffusers - Streamline )=20
>> But importantly the environment it ends up in. The pape= rs share data for ideal conditions with for example unobstructed exit air p= aths.=20
>> My thoughts now are that this has a significant impact = on the performance and therefore the advantage of instrumenting in flight a= nd reshaping for actual conditions.=20
>>=20
>> The data I collected yesterday of our H2O diffuser reve= als that the air flow in various points across the face are very different.= =20
>> Simplified, if I average the pressures at the five poin= ts I measured, then comparatively the back is up 20%, the centre up 25% and= the front down 60% from that average figure.=20
>> I=E2=80=99m figuring a 20% difference is probably OK, b= ut my front to back/middle difference of ~80% down in the front top of that= radiator may hold significant room for improvement.=20
>> Further, my data suggests that as IAS rises those diffe= rences are amplified.=20
>> So I am now targeting the modifications for our worst c= ase conditions of WOT sea level ~200hp and initial climb numbers of 115KIAS= .=20
>>=20
>> Cheers.=20
>>=20
>> Steve Izett=20
>>=20
>>=20
>>=20
>>> On 21 Nov 2020, at 3:37 am, ROY GLENN=20 rglenn14@sbcglobal.net=20 <flyrotary@lancaironline.net> wrote:=20
>>>=20
>>> Could some ne post a photo of their wedge shape and= dimensions.=20
>>> Thanks Roy=20
>>>=20
>>> --=20
>>> Homepage:=20 http://www.flyrotary.com/=20
>>> Archive and UnSub:=20 http://mail.lancaironline.net:81/lists/f= lyrotary/List.html=20
>>=20
>=20
>=20
>=20
>=20
> This email has been checked for viruses by Avast antivirus = software.=20
>=20 = www.avast.com=20
>=20
>=20
> <rad duct1.JPG>--=20
> Homepage:=20 http://www.flyrotary.com/=20
> Archive and UnSub:=20 http://mail.lancaironline.net:81/lists/f= lyrotary/List.html=20


--=20
Homepage:=20 http://www.flyrotary.com/=20
Archive and UnSub:=20 http://mail.lancaironline.net:81/lists/f= lyrotary/List.html
=20
=20
=20 
--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.=
net:81/lists/flyrotary/List.html
=20
=20
=20


=20 =20 =20 =20 =20 =20 =20 =20
3D"Avast

This email has been checked for viruse= s by Avast antivirus software.
www.avast.com

=20
=20
=20 ------=_Part_16579_1296511144.1605925364562--