<DOC>
<DOCNO>
439
</DOCNO>
<TITLE>
a factor affecting transonic leading edge flow separation .
</TITLE>
<AUTHOR>
wood,g.p. and gooderum,p.b.
</AUTHOR>
<BIBLIO>
naca tn.3804, 1956.
</BIBLIO>
<TEXT>
  a change in flow pattern that was observed as the free-stream mach
number was increased in the vicinity of 0.8 was described in naca
technical note 1211 by lindsey, daley, and humphreys .  the flow on the
upper surface behind the leading edge of an airfoil at an angle of
attack changed abruptly from detached flow with an extensive region of
separation to attached supersonic flow terminated by a shock wave .  in
the present paper, the consequences of shock-wave--boundary-layer interaction
are proposed as a factor that may be important in determining the
conditions under which the change in flow pattern occurs .  when the
mach number is high enough, the attached-flow pattern exists because
then the shock wave is far enough behind the leading edge to keep the
influence of the high pressure behind the shock wave from extending
through the boundary layer to the immediate vicinity of the leading edge
and affecting the flow there .  some experimental evidence in support of
the importance of shock-wave--boundary-layer interaction is presented .
</TEXT>
</DOC>
