<DOC>
<DOCNO>
634
</DOCNO>
<TITLE>
effects of leading edge bluntness on flutter characteristics
of some square- planform double-wedge airfoils at a
mach number of 15 .4.
</TITLE>
<AUTHOR>
goetz,r.c.
</AUTHOR>
<BIBLIO>
nasa tn.d1487, 1962.
</BIBLIO>
<TEXT>
  results are presented from a wind-tunnel
investigation in helium flow at a
mach number of 15.4 .  the models were
square-planform, double-wedge, shaft-mounted
airfoils with leading- and trailing-edge
radii of 0, 1, 3, and 6 percent chord .
in general, the tests indicate that bluntness
effects on the model flutter characteristics
are stabilizing as the leading-edge
radius is increased from 0 to
destabilizing with further increase in
bluntness .
  results of flutter calculations made
by using newtonian theory aerodynamics
and a combination of newtonian theory and
piston theory aerodynamics in conjunction
with an uncoupled two-mode analysis
are compared with experimental results .
the piston-theory results accurately
predicted flutter speeds for the models with
</TEXT>
</DOC>
