Monty Roberts wrote:

Russel,

I see what you are talking about. I do agree that the static pressure at
this location may be somewhat  lower due to the reduction in cross section.
To move the intake forward to the full width section of the fuselage would
mean moving it forward 22 inches. This places the inlet near the middle of
the strake. I would also expect static pressure to be higher under the
trailing edge of the wing than at the middle of the strake (how these two
flow fields interact is anybody's guess. I certainly do not claim to know).
The total pressure available will be the sum of both static and dynamic. I
expect the dynamic term to be the driver here, not static pressure. I also
think that what really matters is the difference between the static pressure
at the outlet and the inlet. I expect that this will be negative (higher at
the inlet). If I do extend the scoop 22 inches forward it will add weight,
and skin friction drag (on both the inside and outside of the scoop because
of the increase in wetted area). This may have been Burt's line of
reasoning, who knows. IMHO the tradeoffs favor the current location. I'm
sure that you could refine the design with a wind tunnel, or even a good CFD
model. Unfortunately these things require both money and time. I really wish
that I had a pressure and velocity distribution plot to work with. Anybody
know if there is one floating around somewhere for a long EZ. Someone posted
a pressure plot for a P51 a while back.

Thanks for the feedback,

Monty

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