A Survey of Unsteady Hypersonic Flow Problems

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between theory and. experiment is to be noted, though it should be understood
that for high Mach numbers the actual aerodynamic damping respresented by
these values is low. The 1-O and for incidenoes up to the
value for shock detachment, thaugh numerical computation may become necessary
for large values of flow turning angle at the nose.
For low aspect ratio w.ngs of thin, sharp section, for b6 and
Id cos A < 1 (where A = sweep angle of the leading edge), the variational
method should be applicable, though its use for the flow round such a orosssection
has not been examined. Only small incidences could be considered,
because the method depends on the fact that the flow in a fluid lamina can be
considered as isentropic.
For pointed slender bodies, the variational methcd can be applied for
Mbs < 1 and for small incidenoes, and the generalized shook expansion method can
be applied for MS > 1 and for large incidences. There may, however, be
limitations on application of the methods arising from the shape of the body
cross-se&ion, or from the difficulty of determining the nose starting conditions
for the shock expansion method.
During/