The fundamental problem with internal rads is there is not
            enough room
            around the engine, the wing and wing spar to get the required
            ducting down through there to feed the internal mounted rads
            on the
            inside walls of the aft fuselage. That will become apparent
            once you get the side mounted alternator and exhaust system
            on the engine. The ONLY choice it to feed them with some
            sort of scoops mounted between the wings on the outside
            sides of the fuselage. You can make them tall and skinny or you
            can make them large and round. If you make them large and round
            you will intrude on the cargo space with the internal ducting
            required.

            Kit builders never want you to change anything :) The
            original problem
            goes back to the basic concept of the airplane. People are
            too  wide
            and the distance from the back of the cockpit to the prop is
            too short.
            That means the sides of the fuselage go back at too sharp of
            an angle.
            Separation will occur. Turbulators or vortex generators mounted
            on the sides of the fuselage will help mitigate but not
            eliminate
            the problem. The entire fuselage might work better if
            totally redesigned
            to the pollywog shape but that was never done. The bi plane
            configuration
            aggravates the situation as it constrains the flow to 2D.
            IMHO I will go
            out on a limb and say the only effect of the out side
            mounted rads
            will be an increase in frontal area and any devices now on
            the sides
            of the fuselage will not be necessary.

            The air coming out of the proposed louvered grills will
            affect the flow as well.

            Perhaps you can make a half mock up and check it on the back
            of a pick up
            truck. I suggested that to Scott Gettings when I saw his
            airplane and he may have built the full scale test  mock up
            all ready.

            Another option is increase the length of the cowl and put
            the rads
            up in front of the engine. I think Rino flew his airplane
            with that configuration. I don't know if it cooled or not.

            This airplane holds the worlds record for ACRE volume of
            cooling discussion :)

            Paul Lamar



        Yes I have the mockup built, with water pressure measurement
        ports, etc. I haven't built the radiator/vanes or "flown" the
        whole thing on top of my truck yet.  I'll see if I can dig up a
        picture.

        This delay is because my regular job has just taken all of my
        time.  Maybe Sandy can come down for a weekend and we'll do the
        whole thing!

        Scott  Gettings


    Paul,

    I did not extend the cowling because there is no more space up front,
    extending it, it would overhang over the canopy which then could not be
    opened.

    Rino

    Ah so. Right! I forgot. We are between  a rock and a hard spot here.
    Does anybody have CFD up and running?

    Paul Lamar


    Paul and group:

    Here is one last iteration that I wonder if it might be worth
    studying when I do the airflow/pressure testing on my Goose
    fuselage/wing mockup:

    A front radiator design (see the cardboard mockup in the first pic)
    argues heavily for a pair of oil coolers somewhere else on the
    plane.   We are currently looking at embedding a pair of coolers in
    turning vanes, or ducted beside the pylon (as per Paul's  previous
    postings).

    A previously-considered idea was to use armpit scoops and duct air
    back to coolers somewhere around the pylon.  This was originally not
    felt to be feasible.

    The RX8 oil coolers are about 125 cu in each, which would require
    about 125/2*.30 for 2" thick coolers, or about 18 sq inches of
    intake area.  This could be accomplished with a 6"x3" duct tucked
    under each upper wing.   If the duct ended in a wedge diffuser under
    a cooler that was embedded in the wing root just outside the
    cowling, would the  top of the wing and retreating cowling give an
    attractively-low pressure area on top of the cooler?   Obviously,
    the whole wing root and cowling interface area would have to be
    blended together.  One of Paul's previous drawings showed an
    extended wing root.

    I remember that one plane (Velocity?) did not have much luck with
    under-wing ducts and upper surface air exit ducting.  However, this
    is just a mockup exercise.

    If this might be worthwhile, I could also mock this version up and
    get some pressure measurements along with the other options.

    Scott Gettings

I think we can get a 12 by 12 Setrab oil cooler for the other side
and use a larger rad on just one side. Dave Leonard has had good luck
with this Setrab oil cooler. Al Gietzen finally got that 3 rotor Velocity
cooling pretty good.

http://www.rotaryeng.net/final-cut2-Al-Gietzen-Velocity.wmv

Paul Lamar