Anderson Ed wrote:

Like the idea about adjustable vortex fence around the NACA duct, will
give it a try.

Thanks

Ed

Paul Lamar Wrote:

Don't bother Ed. After seeing your sketch I don't think it will
help much. Focus on strightening that duct.

The NACA duct in that position is not working the way it should. I would
do away with it and use a conventional boundry layer bypass snorkel
scoop with a vertical opening.
Paul

Jeff Spitzer wrote:

 A NACA scoop only works when properly aligned with
the local airflow.  If you like the NACA maybe it would be less work to cut
it out and turn it rather than start over with a pitot scoop. In that case the
NACA should work just fine and appears to be plenty big.  I really think
this is the root of ALL your problems.  DON'T ADD LIPS TO THE NACA ENTRY!
You already have a problem that will be made worse, not better, by the
addition of lips.  Tape some yarn tufts to the cowl and run the engine.
Note the direction of the airflow where you want to put the NACA.  The
centerline must align with the streamlines.  You could also use oil drops
as then you would have something to trace for the rework direction.

Jeff Spitzer

 
The Aircraft Rotary Engine Newsletter.              Powered by Linux.

http://home.earthlink.net/~rotaryeng/            http://www.linux.org