> Something is causing a high pressure bubble to form just outside the
> mouth of the-intake and the thread is showing that bubble
> is-preventing air-flow from entering the intake. In fact, it appears
> to be rejecting flow without the zigzag or vortex generators on about
> half the-diameter-of the intake on the left, particularly on the
> outboard edge.-
John,
As I look at your pix posted Mar. 11 (the one w/ you giving the "thumbs
up"), I'm noticing the cowling shape immediately below the 4" inlet. It
may just be a function of the light in the pix but it appears that the
cowl shape forms something of a ramp for air moving vertically from the
prop rotation. Could this be a factor in creating the high pressure
bubble you speak of? Might it be that the cowl shape tends to sweep air
vertically across the inlet which interferes with airflow into the
inlet?
In comparing the two inlets, the portion of your cowl below the left
inlet (appearing as bright white in your pix) would be the principal
difference in the cowling geometry which the air from the propeller
"sees" as it rotates as it approaches the inlets left and right.
I'm wondering if a concentric lip projecting forward of the inlet...say
maybe as much as an inch (?)...could act in such a way as to divert
that vertically rising air around the inlet, reducing pressure in front
of the inlet, and increasing flow into your duct...? (I'm aware that
you've already tweaked the cowling geometry around the inlets.)
At the very least, it appears to me that it would lessen the degree to
which prop rotation influences flow into the inlets.
Just a thought...
Fred
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