> >> > Paul and group,
> >> >
> >> > I finally have my Renesis mounted, and now I need to pursue the
> >> > cooling.  I've studied Paul's articles and all the cooling
> threads>> > here, but it looks like I may have several options.  I
> would>> appreciate> some help so I might have a chance of getting
> it as close to
> >> right as
> >> > possible!
> >> >
> >> > As per the attached pix, it is obvious  that the standard
> cowling is
> >> > far too wide (about 30", and just a little short) for this
> >> engine.  I
> >> > can narrow the two bottom cowling halves without any problem, but
> >> the> fit around the prop. is still too big.
> >> >
> >> > Perhaps I should just  implement the best possible cooling scheme
> >> and> build a new cowling to fit.  Other than overall drag, there
> are very
> >> > few real constraints on the  size and shape of a custom
> cowling for
> >> > this plane.  Cooling is obviously more important.
> >> >
> >> > For the radiators, it looks like there are at least 2 reasonable
> >> > options.  The first is to put two radiators sitting at about a 45
> >> > degree angle back, and tilted back from the top, in front of the
> >> engine> (see pic).  This can support two radiators about 17x12",
> but does
> >> not
> >> > account for the oil cooler. I can make appropriate ducting to
> >> both of
> >> > these without too much trouble.  This has been done by other
> Goose>> > builders, but with small radiators and no ducting.  It
> seems like
> >> this> option needs quite a bit of width to work.
> >> >
> >> > Another option might  be to put a slightly larger, single
> >> radiator in
> >> > the front, and another radiator (or two) on the cool side of the
> >> > engine.  The side looks like it could easily handle a radiator
> about>> > 14x22"  Notice the RX-7 oil cooler in this location on
> one pic.
> >> This> would  have to use a 90-degree-entry style duct that fed
> from the
> >> front
> >> > of the cowling, beside the front radiator.  The hot air could
> exit>> > either out the side of the cowling, or toward the engine.
> This>> would> give a much narrower cowling than with 2 radiators up
> front.>> >
> >> > The side version could handle the stock oil cooler (5"x22") as
> >> well as
> >> > a 9x22" water radiator.  However, there is another possibility
> >> for an
> >> > oil radiator if I still need more volume.  Down under the  rear
> >> support> bridge (see pic), there is a space that would handle
> about
> >> 10x14"> radiator.  Air would have to be ducted down to this
> area, but I
> >> could
> >> > probably get a 4" diameter tube to it.    It might  also need
> a fan,
> >> > because it would get no airflow unless the plane was moving.
> >> Perhaps> an automotive-style fan and fan shroud might  work?
> Some
> >> builders have
> >> > placed the 0-320 cooler in this location, with mixed results.  No
> >> one> has used a fan.
> >> >
> >> > The Goose normally ingests a lot of air through its appx. 9"x15"
> >> > intake, and sends most of it  into the pylon after cooling the
> >> engine.> It exits at the rear of the pylon through 'augmentation
> slots'>
> >> supposedly to help deliver air to the prop.  This is obviously more
> >> > intake area than is necessary just to cool the engine.
> >> >
> >> > Is there a better solution than any of these ideas?  I suppose
> the>> > questions boil down to:  what is the smallest, most
> efficient way to
> >> > group water and oil radiators of certain sizes around the
> engine in
> >> > order to achieve the necessary cooling (240hp) with the least
> drag?>> > Your ideas and suggestions are greatly appreciated!
> >> >
> >> > Thanks,
> >> >
> >> > Scott Gettings
> >> >
> >> > Real nice work on the motor mount Scott.
> >> >
> >> > I think you are being a bit optimistic on the HP.
> >> > With only four ports and a 2.85:1 PSRU you will
> >> > be limited to about 7000 to 7500 and about 190 HP
> >> > +/- 10 HP depending on the muffler and prop. Given that, one
> >> > 17" x 12" x 2" rad should work fine with a K&W truncated
> >> > well sealed diffuser vertically mounted in front of the engine.
> >> > The oil cooler can go on the plug side in a simple
> >> > K&L wedge diffuser. A Paul Lipps prop mounted close
> >> > to the rear cowl opening will enhance the air flow
> >> > through the engine compartment and the heat exchangers.
> >> >
> >> > More pictures next meassge.
> >> >
> >> > Paul Lamar ...No rotor no motor.
> >>
> >> >Here's what I did.
> >> Bill Hyde
> >>
> >> I assume it is working well Bill.
> >> Did you fix the crash landing damage?
> >>
> >> Paul Lamar
>
>
> > Thanks, Bill.
> >
> > What is the size of your front radiator and cowl intake?
> > I see you used the stock oil cooler.
> >
> > Did this arrangement cool satisfactorily?
> >
> > Scott Gettings
> >
>
>
> >I don't have that aircraft anymore. The cowling was made by me
> (way to much
> >work). The radiator was custom made and the oil cooler was
> provided by the
> >same company (not stock but same volume). They are located in
> Indianapolis
> >but I can't recall their name.
> Bill Hyde
>

So Bill used custom coolers!  I'm investigating sources, but it looks like custom may be the way to
go to get
exactly the size needed.  Almost all auto radiators are way too big.  Stock A/C evaporators (and
condensers?)
are much closer to the needed radiator size (12x17"), but would need to have larger intake and exit
tubes
welded on (I haven't found any with 1.5" connectors yet).  If any one has any styles, brands or
custom suppliers
of smaller water/oil radiators they have had especially good luck with, please let me know!

In the front-and-side radiator option we've been discussing, it looks like there is a LOT more
potential room on
the cool side of the engine than in the front.  As the front (water) radiator gets to around 17x12"
(204 sq inches
area, and 400 cubic inches if 2" thick), it quickly determines the cowling size.  Keeping this
radiator as small as
possible will allow a small frontal area cowling, such as Bill did.

Perhaps a rectangular oil cooler of about the same area (but only 1" thick) should go up front??  Or
smaller and
1.5" thick.  This could  equate to the usual 190 cubic inches for the 13B oil radiator and give a
little smaller
frontal area.   It would  allow a larger and thinner water radiator on the side.  The downside is
the hoses would
all be much longer in this arrangement.

Yet another option is to keep a 400 cu. inch water radiator up front (accepting a slightly larger
cowling), but
make the oil cooler larger than the usual 190 cubic inches.   I know the stock oil cooler is good,
but the RX-8
uses two, appx. 7x9x2" coolers for about 240 cubic inches that are very light.

 Is there any disadvantage to letting a larger oil cooler assume more than its normal 1/3 share of
the total
cooling volume?  A 12x20x1" oil cooler would easily fit on the side, and if it were 1.5" thick would
be 360 cubic
inches of oil cooling volume.  Is this overkill?

Thanks again for helping with all these variables...

Scott Gettings


Try Ed Kelpeis he can build you almost anything.
The oil cooler can be any size. The main thing is it must
be good for 150 psi or more. Better to test to 300 psi.

Edward Klepeis <techwelding@comcast.net>


Paul Lamar ...No rotor no motor.

Take a look at summit racing . I used a griffin 13/18/2  with 1.5 and
1.75 hose necks. Both necks are on the same tank.

Geir



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