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

"Kevin R. Walsh" wrote:

There was just a discussion about this on the Cozy mailing list as
someone was adding VGs in fron of their NACA scoop.  They found that
after adding 2 VGs they could get the same inlet pressure (as measured
by an ASI) as the free stream.  The location of the NACA is the same as
the scoop shown in the CAD drawing, so I think this is all academic...

Kevin
Kevin Russert Walsh
Sr. Process & Equipment Development Engineer

 
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