Can Dan analyze this?  It is a pusher LEZ, this is a very approximate
drawing of my oil cooler installation.  I've probably tried a dozen
different things over the years and oil still doesn't cool very well.
The exit on top of the cowl is now basically open, just several  "fixed
cowl flaps" at a 45 degree angle.

Perry

Perry, what is the distance from the scoop opening to the leading edge of
the strake? That will have a strong effect on the boundary layer thickness
and consequently the simulation. Perhaps you should redraw it to scale.

Paul Lamar

Perry Mick wrote:

It is about one inch and I did draw it to scale, but from memory. Strake
is about 10" thick. Inlet opening is 5" x 5".

Still need the horizontal distance from the opening to the leading edge of the strake.
Very important to see if the P51 type boundary layer bypass is working.
Also the airflow over the top of the strake should be included.

Paul Lamar

My estimate was only off by a factor of two.  It is four feet from the leading edge of the
strake to the inlet, the strake is swept back at about 60 degrees changing to a sweep of
about 45 degrees at that point.

Perry

We will have to ignore the 3D flow around the swept back leading edge for now.
The boundary layer thickness is also a function of the angle of attack so
Dan, please run  0 and  5 degrees. Dan will need IGES drawings for both
cases Perry. Does your cad program output IGES?

Paul Lamar

I don't have anything that does IGES, can you convert this DXF to IGES? I can also send it in
any of several DWGs I think.
Perry Mick

 
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