Bill Freeman wrote:

Al,

The diffuser looks great, but I wonder if a 5/8" high
scoop will get into freestream air?  I imagine that
the boundary layer is about that thick or so that
far back.  You might find out that you will need a
scoop extended about 5/8" with a boundary air splitter
and extending about a 1 inch into the freestream flow.

Make sure that the scoop is thin with knife edges since
you want to avoid any external diffusion with this internal
diffuser.  External diffusion would be caused by wide
rounded lips on the scoop and would increase the inlet
pressure, but at the expense of mass flow.  With a
narrow inlet like that you need full freestream velocity
into the inlet to get the massflow you need, and then
slow it down and increase the pressure in your nicely
shaped internal diffuser.

I think I agree with Paul that you would want to open up
the top corner in the exit essentially to the top skin, as he
sketched in red on one of the photos.  Might work OK
as is, tho.

I'm impressed with your industriousness.  Looks like a
LOT of work.    Well done!

Bill

 
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