X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from el-out-1112.google.com ([209.85.162.177] verified) by logan.com (CommuniGate Pro SMTP 5.2.10) with ESMTP id 3287999 for flyrotary@lancaironline.net; Wed, 12 Nov 2008 16:34:30 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.162.177; envelope-from=rotary.thjakits@gmail.com Received: by el-out-1112.google.com with SMTP id z25so363707ele.7 for ; Wed, 12 Nov 2008 13:33:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:in-reply-to:mime-version:content-type:references; bh=TdLfdl/mqO0dOsYcGwupdlCKULtjX4s5pJH9CD3O3go=; b=es4/CU9E/Z0D2IB67mUoRioWg+R1zNxZmdXWmiR+rJ2ZSgNaRzPnMWtdA6L2t6AjLa 12UnTxwcvEsGFXB/6iinCCqkmMDVZDeVp659DXE9fIMnVccWzOjLfkbMnH5dlbfnAAPK cF0VC6bp46tluXSeLqGQaLQD0LVPL0mSbALWA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version :content-type:references; b=usETZsNsl1F1NyJD8yQcOSmrNijsroSVNV62yDGXjQirVKLDzxX7V9GGCWAbGl5cEJ xtt7ACari8Vo/C5+fb44YBKY6x3Kbk3fMNclmQ6ckrIjDWhGouMUGc6vzc/uuTL4Gf7H 9iTH8N5HtQ5mQs2G9tsVyOGm3dIGSi90ZJwig= Received: by 10.142.14.18 with SMTP id 18mr2737794wfn.72.1226525633389; Wed, 12 Nov 2008 13:33:53 -0800 (PST) Received: by 10.143.1.6 with HTTP; Wed, 12 Nov 2008 13:33:53 -0800 (PST) Message-ID: <63163d560811121333x1d0d88dgca9e8e27994d1bb8@mail.gmail.com> Date: Wed, 12 Nov 2008 16:33:53 -0500 From: "Thomas Jakits" To: "Rotary motors in aircraft" Subject: Re: [FlyRotary] Re: Cooler orientation In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_21793_14652045.1226525633348" References: ------=_Part_21793_14652045.1226525633348 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline Hi Lynn, Bob thanks for the reply! Makes perfect sense! If you went into the sites I posted you already saw the installations. The one you refer to isa racing installation, the other a sport bike, both aftermarket. OEM always was bottom everything. Bob, this idea I had already a long time ago. Need to take off the cooler I have at home at have a look/see IF it actually is built like this, this whole discussion is obsolete :) Most if not all the air would be purged from the cooler..... I'll be back with details, as soon as I get home, come Monday.... Thanks again! Thomas On Tue, Nov 11, 2008 at 11:06 PM, Bob White wrote: > On Tue, 11 Nov 2008 18:06:45 -0800 > "Lynn Hanover" wrote: > > > The way I was visualizing it, if you have a bottom inlet then you > > would have a top outlet and vice versa. I agree with what you are > > saying, but suspect you might get better distribution through the > > exchanger if the input were on the bottom. > > > > I learned the ineffectiveness of plumbing a heat exchanger wrong with > > the heater core on my old '52 Ford. Since radiators outlets were on > > the bottom and inlets on the top, I reasoned that the heater core > > should be the same. As soon as the water level in the system got a > > little low (and it always did), the heater would only blow cold air. > > After switching the hoses around, water going in the bottom would > > always fill the core to the top outlet and the heater worked just fine > > even with low water in the cooling system. > > > > Bob W. > > > > On Tue, 11 Nov 2008 18:00:32 -0500 > > "Thomas Jakits" wrote: > > > > > Hi Bob, > > > > > > thanks for your reply! > > > > > > In both installations the oil-cooler is above the oil level by a good > > > margin. > > > > > > In my opinion the inlet position is not the critical issue, but the > > outlet. > > > > > > As the oil slows down considerable in the inlet tank, it may (or not) > > loose > > > the ability to push all the air out in front of it. > > > If at the initial filling of the cooler after start-up (or opening of > the > > > thermostat) air gets trapped at the top of the cooler, this air never > gets > > > pushed out, just compressed to oil pressure values. > > > With a top outlet, the air has no choice but leave the cooler through > the > > > outlet.... > > > > > > Am I way out there ????? > > > > > > > > > thjakits > > > > > > On Tue, Nov 11, 2008 at 2:46 PM, Bob White wrote: > > > > > > > Hi Thomas, > > > > > > > > If the oil cooler is below the oil level in the bike, I don't think > top > > > > or bottom inlet will matter too much. If it's above the oil level in > > > > the pan, then bottom inlet will ensure the cooler is always full of > oil. > > > > > > > > My 2 cents and that's probably more than it's worth. :) > > > > > > > > Bob W. > > > > > > > > On Tue, 11 Nov 2008 14:27:00 -0500 > > > > "Thomas Jakits" wrote: > > > > > > > > > Hi all, > > > > > > > > > > I know this is a rotary and aviation list, but there is a lot of > > cooling > > > > > going on here, so I just dare to ask a OFF TOPIC - no pics, so it > > should > > > > > load quick too :) > > > > > > > > > > I would like to ask specifically* Lynn Hanover*, but if anyone else > > knows > > > > > something too, please let me know! > > > > When the inlet and outlet must be on the bottom, the cooler needs to be > long > > in tube length and short in tube count. Like a stock Mazda cooler or an > MGA > > cooler. This keeps trapped air exposed to fast moving oil. Few tubes > means > > higher velocity. And trapped air is minimized and not such a big problem. > > > > Where the tube count is high, and the tube length is short large amounts > of > > air may be trapped in the upper tubes, while hot oil uses the lower > tubes. > > When oil pressure is very high and velocity improves through the cooler, > > much of the air is moved out of the cooler and appears in the pan or > reserve > > tank. > > > > Whenever oil coolers are mounted, no matter the location of the inlet, > the > > outlet must be as high as possible. Oil in a piston engine foams and > becomes > > an insulator. It becomes compressable. It begins to act unlike a > lubricant. > > Engine parts run hotter. Air entrainment adds volume. So the sump may > appear > > over filled. The one motorcycle seems to have it right with inlet and > outlet > > on top. When the cooler has to be up and down, then inlet at the bottom > is > > of course required, because the outlet *must* be on top. > > > > The foaming problem in the rotary is worse, due to the two oil jets > > squirting oil into the spinning rotors. Multi grade oils add to the > foaming > > problem because of long polymer chains that link up when heated. A > straight > > weight oil foams less than multi-grades. Racing oils even less because > they > > have more anti foaming agents than street oils. > > > > I find water cooling far less difficult. The in at the bottom out at the > top > > seems less important, as water gives up air bubbles readily. > > > > Lynn E. Hanover > > > > One additional thought that occurred to me was that if you needed the > outlet fitting on the bottom for simplifying hose routing, the output > could could have a tube extending to the top internally. > > Bob W. > > > > -- > N93BD - Rotary Powered BD-4 - http://www.bob-white.com > 3.8 Hours Total Time and holding > Cables for your rotary installation - http://roblinstores.com/ > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > ------=_Part_21793_14652045.1226525633348 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline
Hi Lynn, Bob
 
thanks for the reply!
 
Makes perfect sense!
 
If you went into the sites I posted you already saw the installations.
The one you refer to isa racing installation, the other a sport bike, both aftermarket.
OEM always was bottom everything.
 
Bob, this idea I had already a long time ago. Need to take off the cooler I have at home at have a look/see IF it actually is built like this, this whole discussion is obsolete :)
Most if not all the air would be purged from the cooler.....
 
I'll be back with details, as soon as I get home, come Monday....
 
Thanks again!
 
Thomas
On Tue, Nov 11, 2008 at 11:06 PM, Bob White <bob@bob-white.com> wrote:
On Tue, 11 Nov 2008 18:06:45 -0800
"Lynn Hanover" <lehanover@gmail.com> wrote:

> The way I was visualizing it, if you have a bottom inlet then you
> would have a top outlet and vice versa.  I agree with what you are
> saying, but suspect you might get better distribution through the
> exchanger if the input were on the bottom.
>
> I learned the ineffectiveness of plumbing a heat exchanger wrong with
> the heater core on my old '52 Ford.  Since radiators outlets were on
> the bottom and inlets on the top, I reasoned that the heater core
> should be the same.  As soon as the water level in the system got a
> little low (and it always did), the heater would only blow cold air.
> After switching the hoses around, water going in the bottom would
> always fill the core to the top outlet and the heater worked just fine
> even with low water in the cooling system.
>
> Bob W.
>
> On Tue, 11 Nov 2008 18:00:32 -0500
> "Thomas Jakits" <rotary.thjakits@gmail.com> wrote:
>
> > Hi Bob,
> >
> > thanks for your reply!
> >
> > In both installations the oil-cooler is above the oil level by a good
> > margin.
> >
> > In my opinion the inlet position is not the critical issue, but the
> outlet.
> >
> > As the oil slows down considerable in the inlet tank, it may (or not)
> loose
> > the ability to push all the air out in front of it.
> > If at the initial filling of the cooler after start-up (or opening of the
> > thermostat) air gets trapped at the top of the cooler, this air never gets
> > pushed out, just compressed to oil pressure values.
> > With a top outlet, the air has no choice but leave the cooler through the
> > outlet....
> >
> > Am I way out there ?????
> >
> >
> > thjakits
> >
> > On Tue, Nov 11, 2008 at 2:46 PM, Bob White <bob@bob-white.com> wrote:
> >
> > > Hi Thomas,
> > >
> > > If the oil cooler is below the oil level in the bike, I don't think top
> > > or bottom inlet will matter too much.  If it's above the oil level in
> > > the pan, then bottom inlet will ensure the cooler is always full of oil.
> > >
> > > My 2 cents and that's probably more than it's worth. :)
> > >
> > > Bob W.
> > >
> > > On Tue, 11 Nov 2008 14:27:00 -0500
> > > "Thomas Jakits" <rotary.thjakits@gmail.com> wrote:
> > >
> > > > Hi all,
> > > >
> > > > I know this is a rotary and aviation list, but there is a lot of
> cooling
> > > > going on here, so I just dare to ask a OFF TOPIC - no pics, so it
> should
> > > > load quick too :)
> > > >
> > > > I would like to ask specifically* Lynn Hanover*, but if anyone else
> knows
> > > > something too, please let me know!
>
> When the inlet and outlet must be on the bottom, the cooler needs to be long
> in tube length and short in tube count. Like a stock Mazda cooler or an MGA
> cooler. This keeps trapped air exposed to fast moving oil. Few tubes means
> higher velocity. And trapped air is minimized and not such a big problem.
>
> Where the tube count is high, and the tube length is short large amounts of
> air may be trapped in the upper tubes, while hot oil uses the lower tubes.
> When oil pressure is very high and velocity improves through the cooler,
> much of the air is moved out of the cooler and appears in the pan or reserve
> tank.
>
> Whenever oil coolers are mounted, no matter the location of the inlet, the
> outlet must be as high as possible. Oil in a piston engine foams and becomes
> an insulator. It becomes compressable. It begins to act unlike a lubricant.
> Engine parts run hotter. Air entrainment adds volume. So the sump may appear
> over filled. The one motorcycle seems to have it right with inlet and outlet
> on top. When the cooler has to be up and down, then inlet at the bottom is
> of course required, because the outlet *must* be on top.
>
> The foaming problem in the rotary is worse, due to the two oil jets
> squirting oil into the spinning rotors. Multi grade oils add to the foaming
> problem because of long polymer chains that link up when heated. A straight
> weight oil foams less than multi-grades. Racing oils even less because they
> have more anti foaming agents than street oils.
>
> I find water cooling far less difficult. The in at the bottom out at the top
> seems less important, as water gives up air bubbles readily.
>
> Lynn E. Hanover
>

One additional thought that occurred to me was that if you needed the
outlet fitting on the bottom for simplifying hose routing, the output
could could have a tube extending to the top internally.

Bob W.



--
N93BD - Rotary Powered BD-4 - http://www.bob-white.com
3.8 Hours Total Time and holding
Cables for your rotary installation - http://roblinstores.com/

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

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