<DOC>
<DOCNO>
453
</DOCNO>
<TITLE>
the influence of two-dimensional stream shear on airfoil maximum lift .
</TITLE>
<AUTHOR>
</AUTHOR>
<BIBLIO>
</BIBLIO>
<TEXT>
the cornell aeronautical laboratory is conducting a program of
theoretical and experimental research on low-speed aerodynamics as
applied to stol and vtol aircraft .  the objective of this program is to
re-examine certain aspects of classical aerodynamic information, in the
light of low-speed flight requirements, with the aim of seeking aerodynamic
processes which might be exploited to enhance law-speed performance
.
one aspect of propeller-driven aircraft which has recently received
increasing attention is the existence of strong gradients of longitudinal
velocity, or shear, in the propeller slipstream .  this slipstream
shear interacts with a wing surface and can alter the wing
characteristics .  in theoretical treatments of a wing interacting with
a propeller slipstream, the first important simplification is the
replacement of the slipstream with an ideal uniform
jet, free of all velocity
gradients .  the application of these theories requires that one equate
the actual slipstream to an effective uniform jet .  one method employed
is to assume the uniform jet has a momentum flux equal to the
average in the propeller slipstream .  these and similar procedures
are well founded on momentum considerations., however, the implicit
assumption is that the flow nonuniformity, the shear, does not influence
the wing characteristics .
</TEXT>
</DOC>
