Enhancement of laminar flow across an airfoil by PLFC
Enhancement of laminar flow across an airfoil by PLFC
(OP)
SEPARATION/DESTRUCTION OF THE BOUNDRY LAYER AT LOW SPEEDS AND HIGH ANGLE OF ATTACK CAN BE INHIBITED AND DELAYED BY SEVERAL TECHNIQUES.
ONE OF THESE IS VACUUM-INDUCED FLOW THROUGH THE PERFORATED SURFACE OF THE AIRFOIL WING.--ironicly called '\" positive laminar flow control"
THIS WAS INVESTIGATED BEFORE AND AFTER WWII BY THE USA,BRITAIN,& LUFTWAFFE, NASA, MS STATE UNIV AE DEPT.
IT WAS ABANDONED FOR SAFETY REASONS
I HAVE A POTENTIAL APPLICATION, SAFE, FOR GROUND VEHICLES.
DOES ANYONE HAVE ANY EXPERIENCE, REFERENCE OR KNOWLEDGE IN THIS MATTER?
ONE OF THESE IS VACUUM-INDUCED FLOW THROUGH THE PERFORATED SURFACE OF THE AIRFOIL WING.--ironicly called '\" positive laminar flow control"
THIS WAS INVESTIGATED BEFORE AND AFTER WWII BY THE USA,BRITAIN,& LUFTWAFFE, NASA, MS STATE UNIV AE DEPT.
IT WAS ABANDONED FOR SAFETY REASONS
I HAVE A POTENTIAL APPLICATION, SAFE, FOR GROUND VEHICLES.
DOES ANYONE HAVE ANY EXPERIENCE, REFERENCE OR KNOWLEDGE IN THIS MATTER?





RE: Enhancement of laminar flow across an airfoil by PLFC
2. "IT WAS ABANDONED FOR SAFETY REASONS"
No, it was abandoned because the amount of energy needed, and the weight added to the airframe, were not offset by the added lift or reduced drag. Since low-speed, high-AOA conditions are usually seen during landing, it is easier/lighter to create a variable geometry wing using flaps & slats, etc. than to blow/suck on the wing surfaces.
You seem to have a handle on the sources for studies of boundary layer control. I have some limited experience with the subject matter, but would point you to the NASA server and then to a university library that has an aeronautical engineering department for further research.
RE: Enhancement of laminar flow across an airfoil by PLFC
As well as the problems btrue gives, another one was that the holes tend to get blocked by dirt, insects etc.
One supposes this may be worse for a ground vehicle on anything more than a one off land speed record type effort.
KENAT,
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RE: Enhancement of laminar flow across an airfoil by PLFC
RE: Enhancement of laminar flow across an airfoil by PLFC
Do a search for
August Raspet and Boundary Layer Research at Mississippi State
Mis State did a lot of research on this in the 70's
B.E.